Spinal Epidural Abscess

VERSION: 1.0 CREATED: January 27, 2026 STATUS: Approved

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DIAGNOSIS: Spinal Epidural Abscess (SEA)

ICD-10: G06.1 (Intraspinal abscess and granuloma), G06.2 (Extradural and subdural abscess, unspecified), M46.40 (Discitis, unspecified site), M46.46 (Discitis, lumbar region), M46.47 (Discitis, lumbosacral region), A41.9 (Sepsis, unspecified organism)

CPT CODES: 87040 (Blood cultures (x2 sets, before antibiotics)), 85025 (CBC with differential), 80053 (CMP (BMP + LFTs)), 85652 (ESR (erythrocyte sedimentation rate)), 86140 (CRP (C-reactive protein)), 84145 (Procalcitonin), 83605 (Lactate), 86900 (Type and screen), 87389 (HIV antibody/antigen), 85379 (D-dimer), 85384 (Fibrinogen), 87116 (Acid-fast bacilli (AFB) smear and culture), 87102 (Fungal cultures), 93306 (Transthoracic echocardiogram (TTE)), 71046 (Chest X-ray), 78816 (PET/CT (FDG)), 96365 (Empiric IV antibiotics (STAT))

SYNONYMS: Spinal epidural abscess, SEA, epidural abscess, spinal abscess, epidural infection, vertebral osteomyelitis, discitis, spondylodiscitis, spinal infection, back pain with fever, paraspinal abscess

SCOPE: Emergency evaluation and management of spinal epidural abscess in adults. Covers the classic triad (back pain, fever, neurologic deficit), emergent MRI, surgical drainage vs. medical management decision-making, empiric and targeted antibiotic therapy, and neurologic monitoring. Includes associated vertebral osteomyelitis and discitis. Excludes brain abscess (separate template), subdural empyema, and post-operative wound infections (partially overlaps).

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PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | - = Not applicable to this setting

═══════════════════════════════════════════════════════════════ SECTION A: ACTION ITEMS ═══════════════════════════════════════════════════════════════

1. LABORATORY WORKUP

1A. Essential/Core Labs

Test	ED	HOSP	OPD	ICU	Rationale	Target Finding
Blood cultures (x2 sets, before antibiotics) (CPT 87040)	STAT	STAT	-	STAT	CRITICAL: Positive in 60-70%; identifies organism for targeted therapy; guides antibiotic duration; S. aureus most common (60-70%); draw from 2 separate sites	Positive → organism identification; S. aureus (MRSA vs. MSSA) most common; also Streptococci, gram-negatives, anaerobes
CBC with differential (CPT 85025)	STAT	STAT	ROUTINE	STAT	Leukocytosis (WBC >12,000 in 60-80%); left shift; bandemia; baseline for monitoring; thrombocytopenia may indicate DIC/sepsis	Leukocytosis (66%); normal WBC does NOT exclude SEA (20-40% have normal WBC); leukopenia concerning for overwhelming sepsis
CMP (BMP + LFTs) (CPT 80053)	STAT	STAT	ROUTINE	STAT	Renal function (antibiotic dosing, contrast); electrolytes; hepatic function; glucose (diabetes is major risk factor)	Normal or abnormal; elevated glucose → diabetes workup; renal dysfunction affects antibiotic choice
ESR (erythrocyte sedimentation rate) (CPT 85652)	STAT	STAT	ROUTINE	STAT	Highly sensitive (>94%); ESR >20 mm/hr in nearly all cases of SEA; ESR >30-50 typical; useful for monitoring treatment response	ESR >20 mm/hr (sensitivity 94%); mean ESR is typically 50-80 mm/hr; if normal → SEA very unlikely
CRP (C-reactive protein) (CPT 86140)	STAT	STAT	ROUTINE	STAT	Elevated in >90% of SEA; more responsive to treatment changes than ESR; useful for monitoring	Elevated (typically >10 mg/dL); declines faster than ESR with successful treatment
Procalcitonin (CPT 84145)	STAT	STAT	-	STAT	More specific for bacterial infection than CRP; helps distinguish bacterial from non-infectious inflammation; prognostic	>0.5 ng/mL suggests bacterial infection; >2.0 ng/mL concerning for sepsis; useful in atypical presentations
Blood glucose / HbA1c (CPT 82947+83036)	STAT	STAT	ROUTINE	STAT	Diabetes is a major risk factor (30-50% of SEA patients); undiagnosed diabetes common; affects wound healing and immune function	Document diabetes status; HbA1c >6.5% = diabetes; glucose control target <180 mg/dL
PT/INR, aPTT (CPT 85610+85730)	STAT	STAT	-	STAT	Coagulopathy from sepsis (DIC); surgical candidacy; baseline before anticoagulation decisions; epidural hematoma differential	Normal; prolonged → concern for DIC, liver dysfunction; affects surgical risk
Lactate (CPT 83605)	STAT	STAT	-	STAT	Sepsis assessment; tissue hypoperfusion; prognostic	<2 mmol/L (normal); >4 mmol/L = severe sepsis/septic shock requiring aggressive resuscitation
Type and screen (CPT 86900)	STAT	STAT	-	STAT	Surgical candidacy; blood product availability	On file
Urinalysis + urine culture (CPT 81003+87086)	STAT	STAT	ROUTINE	STAT	Urinary source (UTI is common source of hematogenous spread, especially gram-negative SEA); concurrent UTI	Normal or pyuria/bacteriuria; if positive → potential primary source

1B. Extended Workup (Second-line)

Test	ED	HOSP	OPD	ICU	Rationale	Target Finding
HIV antibody/antigen (CPT 87389)	-	ROUTINE	ROUTINE	ROUTINE	Immunocompromised state; increases SEA risk; affects prognosis and opportunistic infection risk	Negative; if positive → CD4 count, viral load; consider opportunistic organisms
Hepatitis B/C serologies	-	ROUTINE	ROUTINE	-	IVDU population (risk factor for SEA); affects long-term antibiotic choice; liver function	Negative; if positive → affects drug selection, hepatotoxicity monitoring
Hemoglobin A1c	-	ROUTINE	ROUTINE	-	Undiagnosed or poorly controlled diabetes	<6.5% (normal); ≥6.5% = diabetes; 5.7-6.4% = prediabetes
D-dimer (CPT 85379)	STAT	ROUTINE	-	STAT	DIC screening; VTE risk (prolonged immobility + inflammation); not specific but elevated in SEA	Elevated (non-specific); very high levels → consider DIC
Fibrinogen (CPT 85384)	-	ROUTINE	-	STAT	DIC assessment; sepsis-associated coagulopathy	>150 mg/dL; low fibrinogen = DIC or consumption
Albumin / prealbumin	-	ROUTINE	ROUTINE	-	Nutritional status; wound healing; chronicity of illness; prognostic	>3.5 g/dL (albumin); low = poor nutrition, chronic illness
Repeat blood cultures (during treatment)	-	ROUTINE	ROUTINE	-	Document clearance of bacteremia; if persistently positive → evaluate for endocarditis, undrained collection, treatment failure	Negative by 48-72h of appropriate antibiotics; persistent positivity → echocardiogram, repeat imaging

1C. Rare/Specialized (Refractory or Atypical)

Test	ED	HOSP	OPD	ICU	Rationale	Target Finding
Surgical specimen culture (intraoperative)	-	STAT	-	-	Gold standard for organism identification; culture of abscess material at surgery; sensitivity higher than blood cultures; also send for Gram stain and histopathology	Organism identification; guides targeted antibiotic therapy
CT-guided aspiration/biopsy culture	-	URGENT	-	-	If non-operative management chosen; tissue diagnosis; culture for organism identification; distinguishes abscess from tumor/hematoma	Organism identification; Gram stain; histopathology (rule out tumor)
Acid-fast bacilli (AFB) smear and culture (CPT 87116)	-	EXT	EXT	-	TB spine (Pott's disease); endemic areas; immunocompromised; chronic presentation with vertebral destruction	Negative; positive → TB requires different treatment (anti-TB regimen; may not need surgery if no instability/neurologic deficit)
Fungal cultures (CPT 87102)	-	EXT	EXT	-	Immunocompromised; IVDU; indwelling catheters; endemic fungi (coccidioidomycosis, blastomycosis, histoplasmosis); chronic presentation	Negative; positive → prolonged antifungal therapy (6-12+ months)
Brucella serology / cultures	-	EXT	EXT	-	Endemic areas (Mediterranean, Middle East); unpasteurized dairy; occupational exposure (farmers, veterinarians); chronic back pain	Negative; positive → doxycycline + streptomycin/gentamicin or rifampin
16S rRNA PCR (on tissue)	-	EXT	EXT	-	Culture-negative SEA; prior antibiotic exposure; fastidious organisms	Identifies organism even when cultures are negative; research/reference lab
Transthoracic echocardiogram (TTE) (CPT 93306)	-	ROUTINE	ROUTINE	STAT	Infective endocarditis screen; IE present in 10-15% of SEA patients with S. aureus bacteremia; affects antibiotic duration and management	Normal; vegetations → endocarditis diagnosis; changes antibiotic duration to 4-6 weeks minimum
Transesophageal echocardiogram (TEE)	-	URGENT	ROUTINE	URGENT	If TTE negative but high suspicion for endocarditis (S. aureus bacteremia, IVDU, prosthetic valve, persistent fever); TEE more sensitive than TTE	Normal; vegetations → endocarditis; TEE sensitivity 90-95% vs. TTE 65%

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2. DIAGNOSTIC IMAGING & STUDIES

2A. Essential/First-line

Study	ED	HOSP	OPD	ICU	Timing	Target Finding	Contraindications
MRI entire spine with and without contrast (gadolinium) (CPT 72156+72157+72158)	STAT	STAT	URGENT	STAT	GOLD STANDARD — within 4 hours of ED presentation if neurologic deficit; within 24h if no deficit; contrast essential for abscess characterization; image ENTIRE spine (multifocal in 15-20%)	Epidural collection with ring enhancement; T1 hypointense, T2 hyperintense; restricted diffusion (DWI bright, ADC dark within abscess); vertebral body involvement (osteomyelitis); disc involvement (discitis); cord compression; degree of canal compromise	MRI-incompatible implants; severe claustrophobia (sedate — do NOT delay); GFR <30 (gadolinium risk — but benefit outweighs risk in emergency)
Plain radiographs (spine)	STAT	STAT	-	STAT	Immediate while awaiting MRI; identifies vertebral body destruction, disc space narrowing, alignment abnormality; LOW sensitivity for early SEA	Disc space narrowing; vertebral body destruction (late finding — takes 2-4 weeks to appear); alignment; pathologic fracture	Pregnancy (shield)
CT spine without contrast (CPT 72125/72128/72131)	STAT	STAT	-	STAT	If MRI unavailable or contraindicated; inferior to MRI for soft tissue and epidural collection; shows bone destruction better than MRI	Bone destruction; disc space narrowing; paraspinal soft tissue mass; canal compromise; less sensitive than MRI for epidural abscess extent	Pregnancy (relative)
Chest X-ray (CPT 71046)	STAT	STAT	-	STAT	Primary pulmonary source (pneumonia); lung abscess; TB (apical infiltrate, cavitation); septic emboli	Primary infection source; pulmonary complications; TB features	Pregnancy (shield)

2B. Extended

Study	ED	HOSP	OPD	ICU	Timing	Target Finding	Contraindications
CT chest/abdomen/pelvis with contrast (CPT 71260+74178)	-	URGENT	ROUTINE	URGENT	Source identification if not obvious; look for primary infection (lung abscess, intra-abdominal abscess, psoas abscess); staging for concurrent infection	Primary source: lung abscess, intra-abdominal abscess, psoas abscess (contiguous spread), renal/perinephric abscess; endocarditis emboli	Contrast allergy; renal impairment
Echocardiogram (TTE → TEE if needed)	-	URGENT	ROUTINE	URGENT	All patients with S. aureus bacteremia should have echocardiogram; endocarditis in 10-15% of S. aureus SEA	Vegetations; valvular regurgitation; abscess; Duke criteria	None (TTE); TEE: esophageal pathology, uncooperative patient
CT myelogram	-	EXT	-	EXT	Only if MRI absolutely contraindicated; intrathecal contrast via LP followed by CT; demonstrates level of compression; risk of meningitis seeding with LP	Complete or partial block; level of compression; intradural vs. extradural	Infection at LP site (SEA itself may preclude LP at involved level); coagulopathy
Nuclear medicine bone scan (Tc-99m)	-	-	EXT	-	If MRI unavailable; can identify osteomyelitis; may show uptake before radiographic changes; less specific than MRI	Increased uptake at infection site(s); may identify multifocal disease	Pregnancy; limited specificity
Gallium-67 or Indium-111 WBC scan	-	-	EXT	-	Chronic/subacute infection; differentiating active infection from degenerative changes; research use	Increased uptake at infection site	Limited availability; time-consuming; replaced largely by MRI

2C. Rare/Advanced

Study	ED	HOSP	OPD	ICU	Timing	Target Finding	Contraindications
CT-guided biopsy/aspiration	-	URGENT	-	-	If diagnosis uncertain; culture acquisition for non-surgical management; distinguish abscess from tumor or hematoma	Organism identification; Gram stain; histopathology confirming infection vs. other pathology	Coagulopathy; inaccessible location; very small collection
PET/CT (FDG) (CPT 78816)	-	-	EXT	-	Chronic/recurrent infection; assess treatment response; identify additional sites of infection; research use	Increased FDG uptake at infection site; may identify occult primary source	Uncontrolled diabetes (glucose >200); pregnancy
Repeat MRI (during treatment)	-	ROUTINE	ROUTINE	-	At 2-4 weeks or if clinical worsening; assess treatment response; monitor for abscess expansion; may appear worse before better on imaging	Stable or decreasing collection size; resolving edema; NOTE: Imaging may lag behind clinical improvement (may appear worse at 2 weeks even with successful treatment)	Same as initial MRI
Post-treatment MRI	-	ROUTINE	ROUTINE	-	At end of antibiotic course (6-8 weeks); baseline for comparison; assess for residual disease	Resolution or significant improvement of collection; healed osteomyelitis; residual enhancement may persist for months (does not necessarily indicate active infection)	Same as MRI

Lumbar Puncture

Study	ED	HOSP	OPD	ICU	Timing	Target Finding	Contraindications
LP — Generally NOT indicated	-	-	-	-	LP is generally CONTRAINDICATED in suspected SEA; risk of seeding infection into subarachnoid space → meningitis/spinal subdural empyema; imaging (MRI) is diagnostic modality of choice	N/A	AVOID LP if SEA suspected — LP may spread infection into intradural space; if meningitis suspected concurrently, discuss with neurosurgery/ID before LP

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3. TREATMENT PROTOCOLS

3A. Acute/Emergent Treatment

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Empiric IV antibiotics (STAT) (CPT 96365)	IV	-	25-30 mg/kg :: IV :: q12h :: Start IMMEDIATELY after blood cultures drawn — do NOT delay for MRI or organism identification; First-line empiric: Vancomycin 25-30 mg/kg IV load (max 2g), then 15-20 mg/kg IV q8-12h (target trough 15-20 mcg/mL) PLUS Ceftriaxone 2g IV q12h OR Cefepime 2g IV q8h; Alternative for β-lactam allergy: Vancomycin + aztreonam 2g IV q8h OR Vancomycin + fluoroquinolone (levofloxacin 750 mg daily); If Pseudomonas risk (IVDU, immunocompromised): Add anti-pseudomonal coverage with cefepime or piperacillin-tazobactam 4.5g IV q6h; Adjust to culture results when available	-	Vancomycin covers MRSA (most important cause); ceftriaxone/cefepime covers MSSA, streptococci, gram-negatives; early antibiotics are associated with better outcomes; every hour of delay increases mortality in sepsis	STAT	STAT	-	STAT
Emergent surgical decompression + drainage	-	-	N/A :: - :: once :: INDICATIONS (Surgery preferred): (1) Neurologic deficit (any weakness, bowel/bladder dysfunction), (2) Sepsis/hemodynamic instability not improving with antibiotics, (3) Significant cord compression on imaging, (4) Failure of medical therapy (no improvement at 48-72h, worsening at any time), (5) Unknown organism (need tissue diagnosis); Procedure: Posterior laminectomy with abscess drainage; cultures from abscess; débridement of infected tissue; may need instrumentation if instability; Timing: Within 24h of diagnosis; emergent (within hours) if progressive deficit	-	Darouiche (2006): Surgical outcomes better than medical management in patients with neurologic deficit; earlier surgery (within 24h) associated with better neurologic recovery; pre-operative neurologic status is #1 predictor of outcome	-	STAT	-	-
DVT prophylaxis	SC	-	40 mg :: SC :: daily :: SCDs immediately; pharmacologic prophylaxis: enoxaparin 40 mg SQ daily — timing is nuanced: may start within 24h of admission if no imminent surgery; post-operatively start 12-24h after surgery per surgeon; high VTE risk population	-	Immobile + infection + inflammatory state = very high DVT risk; mechanical prophylaxis universal; pharmacologic prophylaxis as soon as surgically safe	STAT	STAT	-	STAT
Pain management	IV	-	650-1000 mg :: IV :: q6h :: Back pain often severe; acetaminophen 650-1000 mg q6h (scheduled) + opioids (morphine 2-4 mg IV q3h PRN or hydromorphone 0.5-1 mg IV q3h PRN); NSAIDs: use cautiously (renal function, surgical bleeding) — some ID physicians avoid NSAIDs in active infection; neuropathic agents (gabapentin) if radicular component	-	Severe pain is hallmark of SEA; adequate analgesia is essential; balance with need for neurologic monitoring	STAT	STAT	ROUTINE	STAT
Sepsis resuscitation (if septic)	IV	-	30 mL/kg :: IV :: - :: Surviving Sepsis guidelines: lactate measurement; blood cultures before antibiotics; IV crystalloid 30 mL/kg for hypotension or lactate ≥4 mmol/L; vasopressors (norepinephrine first-line) if MAP <65 despite fluids; reassess volume status; repeat lactate if initially elevated	-	Sepsis from SEA has high mortality; early aggressive resuscitation improves outcomes	STAT	STAT	-	STAT
Glucose control	IV	-	180 mg :: IV :: once :: Target glucose <180 mg/dL; insulin infusion if critically ill; sliding scale or basal-bolus for non-ICU patients; diabetes is major risk factor — optimize control	-	Hyperglycemia impairs immune function and wound healing; tight glucose control improves infection outcomes	STAT	STAT	ROUTINE	STAT

3B. Definitive/Targeted Treatment

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Targeted IV antibiotic therapy (based on culture results)	IV	-	2g :: IV :: q4h :: Tailor to organism and sensitivities; typical regimens: — MSSA: Nafcillin 2g IV q4h OR cefazolin 2g IV q8h (preferred for tolerability); duration 6-8 weeks; — MRSA: Vancomycin 15-20 mg/kg IV q8-12h (trough 15-20) for 6-8 weeks; alternatives: daptomycin 6-8 mg/kg IV daily (avoid if pneumonia), linezolid 600 mg IV/PO q12h (monitor for toxicity if >2 weeks); — Streptococci: Penicillin G 4 million units IV q4h or ceftriaxone 2g IV q12h x 6 weeks; — Enterococcus: Ampicillin 2g IV q4h (if susceptible) ± gentamicin synergy; vancomycin if ampicillin-resistant; — Gram-negatives: Ceftriaxone 2g IV q12h or cefepime 2g IV q8h or ciprofloxacin 400 mg IV q8h x 6 weeks depending on sensitivities; — Pseudomonas: Cefepime 2g IV q8h or meropenem 2g IV q8h x 6 weeks	-	IV antibiotics are standard for SEA/osteomyelitis; oral transition data emerging (OVIVA trial) but traditionally 6-8 weeks IV; de-escalate from empiric coverage once cultures return	-	STAT	ROUTINE	STAT
Duration of antibiotics	IV	-	N/A :: IV :: per protocol :: SEA without osteomyelitis: 4-6 weeks IV; SEA with vertebral osteomyelitis (most cases): 6-8 weeks IV; SEA with endocarditis: 6 weeks minimum from first negative blood culture; duration guided by clinical response, inflammatory markers (ESR, CRP), repeat imaging; may extend if slow response	-	IDSA guidelines: 6 weeks for vertebral osteomyelitis; 4-6 weeks for epidural abscess alone; endocarditis requires 6-week minimum; individualized based on response	-	STAT	ROUTINE	STAT
Oral antibiotic transition (selected cases)	IV	-	750 mg :: IV :: daily :: OVIVA trial (2019): Oral antibiotics non-inferior to IV for bone/joint infections after initial 2 weeks IV in stable patients; Candidates: Clinically improving; afebrile; tolerating PO; CRP trending down; adherent; close follow-up available; Oral options: Fluoroquinolone (levofloxacin 750 mg daily or ciprofloxacin 750 mg BID) + rifampin 300 mg BID (NOT monotherapy); linezolid 600 mg BID (monitor CBC, neuropathy); TMP-SMX DS 2 tabs BID (for MRSA); NOT for: Endocarditis, undrained abscess, persistent bacteremia, non-adherent patient	-	OVIVA trial showed oral switch after 2 weeks IV is non-inferior for bone/joint infections; reduces costs, IV complications, hospital stay; requires careful patient selection and close monitoring; NOT standard for all SEA cases	-	-	ROUTINE	-
Surgical drainage (if not done emergently)	-	-	N/A :: - :: once :: If initial medical management: Re-evaluate need for surgery at 48-72h; indications for delayed surgery: failure to improve, neurologic deterioration, persistent fever/bacteremia, abscess enlargement on imaging; Procedure: Laminectomy + drainage; send cultures even if already on antibiotics (may still grow organism); instrumented fusion if instability/destruction	-	Surgery provides source control, tissue diagnosis, and decompression; delayed surgery for medical failure still beneficial if performed before complete paralysis	-	URGENT	-	-
Medical management alone (selected cases)	-	-	N/A :: - :: q2-4h :: Candidates for medical management without surgery: (1) No neurologic deficit, (2) Organism identified (blood cultures positive), (3) Small abscess (<3 cm collection), (4) Poor surgical candidate (extreme comorbidities), (5) Panspinal disease (multiple levels — surgery impractical); Requirements: Very close neurologic monitoring (q2-4h initially); repeat MRI at 48-72h and weekly; immediate surgery if any deterioration; adherent patient	-	Observational studies: ~40% of SEA can be managed medically if no neurologic deficit and criteria met; HOWEVER, 10-20% will fail medical therapy and require surgery; early surgery generally preferred if feasible	-	STAT	ROUTINE	-

3C. Adjunctive Treatment

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
PICC line placement	IV	-	N/A :: IV :: once :: If prolonged IV antibiotics planned (6-8 weeks); enables outpatient IV therapy (OPAT); placed once stabilized and duration confirmed; confirm tip position with X-ray	-	Required for OPAT; reduces peripheral IV complications; monitor for PICC-associated infection	-	URGENT	ROUTINE	-
Outpatient parenteral antibiotic therapy (OPAT)	PO	-	N/A :: PO :: once :: Once clinically stable (afebrile, pain controlled, neurologically stable, adequate PO intake, safe home environment); PICC in place; infusion teaching completed; close ID follow-up (weekly visits); VNA nursing for line care	-	Reduces hospital stay; comparable outcomes to inpatient therapy in appropriate patients; weekly ID visits with labs (CBC, CMP, drug levels, CRP)	-	ROUTINE	ROUTINE	-
Rifampin (adjunctive)	PO	-	300 mg :: PO :: BID :: For staphylococcal osteomyelitis (vertebral involvement); enhances bone penetration; prevents biofilm; ONLY as adjunctive therapy — never monotherapy (rapid resistance); Rifampin 300 mg PO BID added to primary anti-staphylococcal agent; check interactions (CYP3A4 inducer — reduces warfarin, HIV meds, oral contraceptives, etc.)	-	Rifampin improves outcomes in staphylococcal bone infections; biofilm activity; excellent bone penetration; drug interactions are significant	-	ROUTINE	ROUTINE	-
Bracing / spinal orthosis	-	-	N/A :: - :: continuous :: If spinal instability (vertebral body destruction, kyphosis, instrumentation); TLSO for thoracolumbar; cervical collar for cervical; duration: typically 6-12 weeks or until radiographic healing	-	External stabilization; pain relief; prevents pathologic fracture progression; may allow non-operative management of mild instability	-	ROUTINE	ROUTINE	-
Nutritional optimization	-	-	1.2-1.5 g/kg :: - :: - :: Protein supplementation (1.2-1.5 g/kg/day); calorie optimization; correct vitamin deficiencies; dietitian consultation; affects wound healing and immune function	-	Malnutrition common in chronic illness; protein essential for wound healing; improves infection outcomes	-	ROUTINE	ROUTINE	-
Diabetes optimization	-	-	180 mg :: PO :: - :: Endocrinology consult if poorly controlled; insulin titration; goal HbA1c <7.5% (individualized); glucose <180 mg/dL during acute illness	-	Diabetes is major risk factor; uncontrolled diabetes impairs healing and immune response	-	STAT	ROUTINE	STAT
Substance abuse counseling (if applicable)	-	-	30% :: - :: - :: IVDU is major risk factor for SEA (20-30% of cases); addiction medicine consultation; harm reduction; hepatitis/HIV screening; reduces recurrence risk	-	IVDU patients at high risk for recurrent infection; addressing substance use reduces future SEA risk	-	ROUTINE	ROUTINE	-

3D. Medications to AVOID or Use with Caution

Treatment	Route	Indication	Dosing	Pre-Treatment Requirements	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Daptomycin (with pneumonia)	-	-	-	-	-	-	-	-	-	-
Rifampin monotherapy	-	-	-	-	-	-	-	-	-	-
Linezolid >2-4 weeks	-	-	-	-	-	-	-	-	-	-
Aminoglycosides (prolonged use)	-	-	-	-	-	-	-	-	-	-
Corticosteroids (routine use)	-	-	-	-	-	-	-	-	-	-
NSAIDs (prolonged, peri-operative)	-	-	-	-	-	-	-	-	-	-
LP (in suspected SEA)	-	-	-	-	-	-	-	-	-	-
Epidural steroid injection (as treatment or in area of abscess)	-	-	-	-	-	-	-	-	-	-

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4. OTHER RECOMMENDATIONS

4A. Essential

Recommendation	ED	HOSP	OPD	ICU	Details
Spine surgery / Neurosurgery consultation — EMERGENT	STAT	STAT	-	STAT	Consult IMMEDIATELY on suspicion — before or concurrent with MRI; surgery vs. medical management decision; ALL patients with SEA need spine surgery evaluation even if medical management is planned (contingency for neurologic deterioration)
Infectious disease consultation	STAT	STAT	ROUTINE	STAT	Antibiotic selection; duration; OPAT planning; monitoring plan; repeat imaging decisions; often co-manage with surgery
Neurologic examination — serial monitoring	STAT	STAT	-	STAT	CRITICAL: q2-4h neurologic checks initially; document motor strength (bilateral LE myotomes), sensory level, rectal tone, bladder function; ANY deterioration → STAT surgical evaluation; pre-operative neuro status is the #1 outcome predictor
Source identification	STAT	STAT	ROUTINE	STAT	Identify primary infection source: skin/soft tissue (cellulitis, IV site), UTI, endocarditis, dental abscess, pneumonia, intra-abdominal abscess, recent procedure (epidural injection, spinal surgery); treat primary source
Blood cultures (before antibiotics)	STAT	STAT	-	STAT	CRITICAL — positive in 60-70%; draw 2 sets from separate sites; do NOT delay antibiotics if cultures cause delay — draw quickly and start treatment
Fall precautions / mobility assessment	STAT	STAT	ROUTINE	STAT	SEA patients may have weakness, sensory loss, impaired balance; fall risk assessment; assistive devices; PT/OT evaluation
Documentation of timeline	STAT	STAT	-	STAT	Document: time of symptom onset (back pain → radiculopathy → weakness is classic progression over days-weeks), time of presentation, time of MRI, time of surgical consultation, time of antibiotics, neurologic exam at each time point

4B. Extended

Recommendation	ED	HOSP	OPD	ICU	Details
Echocardiogram (TTE ± TEE)	-	URGENT	ROUTINE	URGENT	All patients with S. aureus bacteremia (IE in 10-15%); if TTE negative but high suspicion → TEE; affects antibiotic duration and management
Dental evaluation	-	ROUTINE	ROUTINE	-	Dental abscess as source; poor dentition as risk factor; dental clearance before prolonged antibiotics (if teeth issues could reinfect)
PICC placement / vascular access	-	URGENT	ROUTINE	-	Long-term IV access for 6-8 weeks of antibiotics; PICC is standard; peripherally inserted; confirm tip position
Social work / case management	-	ROUTINE	ROUTINE	-	OPAT coordination; home infusion setup; substance abuse services; insurance authorization; discharge planning
Addiction medicine (if IVDU)	-	ROUTINE	ROUTINE	-	IVDU is major risk factor (20-30%); buprenorphine or methadone initiation; harm reduction; reduces future infection risk
Pain management service	-	ROUTINE	ROUTINE	-	Chronic pain common after SEA; multimodal approach; avoid long-term opioids if possible; neuropathic agents
Physical / occupational therapy	-	URGENT	ROUTINE	-	Mobility assessment; strengthening; ADL training; rehabilitation planning if neurologic deficits
VNA / home health	-	ROUTINE	ROUTINE	-	PICC care; medication assistance; wound care (if post-operative); safety checks

4C. Atypical/Refractory

Recommendation	ED	HOSP	OPD	ICU	Details
Repeat MRI	-	URGENT	ROUTINE	URGENT	At 48-72h if medically managed (assess for enlargement); at 2-4 weeks (assess treatment response — NOTE: imaging may appear worse before better); at end of treatment (baseline); PRN if clinical worsening
CT-guided drainage (percutaneous)	-	URGENT	-	-	Alternative to surgery in selected cases (poor surgical candidate, small collection, posterior access); less reliable than surgical drainage; may be repeated if recurrence
Revision surgery / repeat drainage	-	URGENT	ROUTINE	-	If treatment failure (persistent fever, neurologic decline, enlarging collection); undrained loculations; retained infected hardware
Infectious disease second opinion	-	ROUTINE	ROUTINE	-	Culture-negative SEA; unusual organism; treatment failure; complex antibiotic decisions
Long-term suppressive antibiotics	-	-	ROUTINE	-	Selected cases with retained hardware, incompletely treated osteomyelitis, immunocompromised; oral suppressive therapy (TMP-SMX, doxycycline, or other based on organism) after initial 6-8 week course; indefinite duration in some cases
Spinal fusion (delayed)	-	-	ROUTINE	-	If significant vertebral destruction and instability after infection controlled; typically 6-12 weeks after infection resolution; staged reconstruction
Hyperbaric oxygen therapy	-	-	EXT	-	Refractory osteomyelitis; adjunctive to antibiotics and surgery; limited evidence but some centers use for difficult cases

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═══════════════════════════════════════════════════════════════ SECTION B: SUPPORTING INFORMATION ═══════════════════════════════════════════════════════════════

5. DIFFERENTIAL DIAGNOSIS

Primary Differential Diagnoses

Diagnosis	Key Differentiating Features	Distinguishing Studies
Malignant spinal cord compression (MSCC) / Metastatic epidural disease	Known cancer history; bone destruction without disc involvement (SEA typically involves disc); no fever (usually); no elevated ESR/CRP/WBC (unless concurrent infection); may be painful but not typically as acute; enhances but no ring-enhancement or diffusion restriction	MRI: enhancing epidural mass WITHOUT ring enhancement or restricted diffusion; bone destruction; CT/PET: metastatic staging; tumor markers; biopsy if uncertain; ESR/CRP may be mildly elevated in malignancy but not as high as SEA
Vertebral compression fracture (osteoporotic)	Older patient; osteoporosis history; no fever; acute onset with movement; no neurologic deficit (usually); no elevated inflammatory markers; vertebral body wedging; may have benign edema	MRI: vertebral body edema WITHOUT epidural collection; no ring enhancement; normal ESR/CRP; DEXA: osteoporosis; mechanism (fall, lifting); responds to bracing/pain management
Disc herniation (without infection)	No fever; no elevated inflammatory markers; unilateral radiculopathy (usually); no epidural collection on MRI; common, benign presentation	MRI: disc herniation without epidural enhancement; no T2 hyperintense collection; normal ESR/CRP; normal WBC; unilateral symptoms more common
Spinal epidural hematoma	Anticoagulation; post-procedural (epidural injection, LP, surgery); acute onset; hematoma signal characteristics on MRI (not ring-enhancing); no fever; rapidly progressive	MRI: epidural collection with blood signal (T1 hyperintense in subacute phase); NO ring enhancement; NO restricted diffusion in hematoma (unlike abscess); coagulation studies; anticoagulation history; recent procedure
Transverse myelitis / NMOSD	Intramedullary (within cord) rather than epidural; autoimmune; no fever; no elevated ESR/CRP (or mildly elevated); subacute onset; responds to steroids/PLEX	MRI: intramedullary T2 hyperintensity, NOT epidural collection; AQP4/MOG antibodies; CSF: pleocytosis but sterile; normal inflammatory markers
Degenerative lumbar stenosis	Chronic symptoms (claudication); older patient; no fever; no inflammatory markers; bilateral symptoms with walking; relieved by sitting/flexion; chronic findings on MRI	MRI: chronic stenosis (ligamentum flavum hypertrophy, disc bulging, facet hypertrophy) WITHOUT acute epidural collection; normal ESR/CRP; chronic history
Vertebral osteomyelitis (without epidural extension)	Similar to SEA but NO epidural collection; disc and vertebral body involvement; back pain and fever; elevated inflammatory markers; may progress to SEA	MRI: vertebral body and disc enhancement and edema WITHOUT epidural collection; blood cultures may be positive; requires IV antibiotics but not emergent surgical decompression (unless instability or progression to SEA)
Psoas abscess	Contiguous spread can cause spinal infection; flank/groin pain; hip flexion pain; may track from spine or vice versa; fever; iliopsoas enhancement on imaging	CT/MRI: psoas muscle enlargement with rim-enhancing collection; may extend to spine; blood cultures; percutaneous drainage often possible

Classic Clinical Triad (Only present in 10-15%)

Phase	Symptom	Timing
Phase 1	Back pain (localized, severe)	Days to weeks before diagnosis
Phase 2	Radicular pain (nerve root irritation)	Days after back pain onset
Phase 3	Neurologic deficit (weakness, bowel/bladder)	Hours to days after radicular pain

NOTE: The classic triad (back pain → radiculopathy → paralysis) is present in only 10-15% of patients at presentation. Most patients present with 1-2 features. Maintain HIGH suspicion in any patient with back pain + fever, especially with risk factors.

Red Flags Requiring Urgent Reassessment

Red Flag	Concern	Action
ANY new neurologic deficit (weakness, sensory loss, bladder dysfunction)	Progression of cord/root compression; medical management failure	STAT MRI; immediate surgical consultation; emergent decompression if progressive
Fever not improving after 48-72h of antibiotics	Undrained collection; wrong antibiotic coverage; drug fever; secondary site	Repeat imaging (MRI); reassess antibiotic coverage; consider surgical drainage
Persistent or worsening back pain	Abscess enlargement; vertebral instability; pathologic fracture	Repeat MRI; surgical re-evaluation; bracing assessment
Persistent bacteremia	Undrained source; endocarditis; seeded secondary site	TEE; repeat imaging; consider surgery for source control
Sepsis not resolving	Inadequate source control; resistant organism; secondary infection	ICU reassessment; surgical drainage if not done; broaden antibiotics; repeat cultures
New back pain at different level	Multifocal SEA (present in 15-20%); skip lesion	MRI whole spine (if not already done); assess new level
Rising inflammatory markers after initial improvement	Treatment failure; secondary infection; abscess loculation	Repeat imaging; reassess antibiotic coverage; surgical consultation

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6. MONITORING PARAMETERS

Acute Phase Monitoring (First 72h)

Parameter	Frequency	Target	Action if Abnormal
Neurologic examination (motor strength, sensory level, rectal tone, bladder)	q2-4h initially; q4-6h once stable	Stable or improving; NO new deficits	ANY deterioration → STAT MRI → emergent surgical consultation → likely emergent decompression
Temperature	q4h	Afebrile (<38°C) by 48-72h of antibiotics	Persistent fever: repeat cultures; imaging for undrained collection; reassess antibiotics; echocardiogram
Blood pressure / hemodynamics	Continuous if septic; q4h if stable	MAP >65; resolving sepsis	Vasopressors; fluid resuscitation; ICU care for septic shock
Pain score (NRS)	q4h	Improving; NRS <4/10	Escalate analgesia; worsening pain may indicate abscess enlargement or instability
Blood cultures (repeat)	Daily until negative	Negative cultures within 48-72h of appropriate antibiotics	Persistent bacteremia: echocardiogram (TEE); imaging for undrained focus; consider surgery
WBC, CRP	Daily initially	Trending down	Rising inflammatory markers: treatment failure; repeat imaging; reassess management
Vancomycin trough (if on vancomycin)	Before 4th dose; then 2-3x/week	15-20 mcg/mL (for serious infection)	Adjust dose if outside range; monitor renal function
Renal function (BUN/Cr)	Daily initially; 2-3x/week ongoing	Stable	Nephrotoxicity: adjust vancomycin and other renally-cleared drugs; adequate hydration
Blood glucose	q6h (q4h if critically ill)	<180 mg/dL	Insulin titration

Subacute Monitoring (Hospital and OPAT)

Parameter	Frequency	Target	Action if Abnormal
Neurologic examination	Daily (hospital); weekly (OPAT)	Stable or improving	New deficits: urgent MRI; surgical re-evaluation
ESR	Weekly	Declining trend (may take 3-4 weeks to start declining); normalize by 6-8 weeks (varies)	Not declining: consider treatment failure; repeat imaging; ID reassessment
CRP	Weekly	Should decline within 1-2 weeks; normalize before ESR	Rising CRP: treatment failure; repeat imaging
CBC (especially if on linezolid)	Weekly	Stable; no cytopenias	Linezolid: thrombocytopenia, anemia → consider discontinuation if <2 weeks remaining or switch agent
Renal function + vancomycin trough	2-3x/week; weekly once stable	Stable; trough 15-20	Dose adjustment
LFTs (if on rifampin)	Weekly	Stable	Transaminases >3x ULN: consider discontinuing rifampin
PICC line site	Daily	No erythema, drainage, tenderness	Line infection: remove PICC; cultures; may need new site
MRI spine	At 2-4 weeks; end of treatment; PRN for symptoms	Improving or stable; abscess resolving; NOTE: imaging may lag behind clinical improvement	Enlarging abscess despite antibiotics: surgical drainage; worsening imaging despite clinical improvement may be normal at 2-4 weeks

Long-term Follow-up

Parameter	Frequency	Target	Action if Abnormal
Clinic visit (ID)	Weekly during OPAT; 2 weeks after completion; 3 months; 6 months; 12 months	No relapse; no recurrence	Relapse: repeat imaging; extended antibiotics; surgical reassessment
ESR/CRP	At end of treatment; 3 months; PRN	Normalized or stable at new baseline	Elevated: repeat MRI; consider relapse
MRI spine	End of treatment; 3-6 months; PRN for symptoms	Resolved or stable; no new disease	New or worsening: relapse; restart antibiotics ± surgery
Functional assessment	Each visit	Improved or stable function	Rehabilitation referral; pain management; chronic deficit management
Spine stability / alignment	Radiographs at 6 weeks, 3 months, 6 months, 12 months if instability	Stable alignment; healing	Progressive kyphosis or instability: surgical stabilization

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7. DISPOSITION CRITERIA

Admission Criteria

Level of Care	Criteria
ICU admission	Sepsis/septic shock; hemodynamic instability; respiratory compromise; post-operative monitoring (surgeon-dependent); severe neurologic deficit with close monitoring needed
General medical/neurosurgery floor	ALL patients with confirmed or suspected SEA require admission; IV antibiotic initiation; neurologic monitoring; surgical evaluation; pre-operative preparation if surgery planned
Observation (NOT appropriate)	SEA is NEVER an observation diagnosis; all patients require admission until diagnosis confirmed/excluded and treatment initiated

Discharge Criteria (Transition to OPAT)

Criterion	Details
Neurologic stability	Stable or improving neurologic exam for ≥48-72h; no new deficits; if deficits present: stable plateau
Afebrile	Afebrile for ≥24-48h on antibiotics
Hemodynamically stable	Off vasopressors; stable vital signs
Organism identified	Blood cultures or surgical cultures positive with sensitivities back; targeted antibiotic regimen
Antibiotic regimen finalized	IV regimen established; OPAT-compatible dosing (once daily or BID preferred); duration plan documented
PICC line placed	Functional PICC; confirmed position; patient educated on care
Pain controlled	Adequate oral pain control; no IV opioid requirement
Safe home environment	Able to care for self or adequate caregiver support; refrigeration for medications; clean environment; phone access
Follow-up arranged	ID clinic within 1 week; spine surgery follow-up (1-2 weeks if post-op); PCP; VNA nursing visits 2-3x/week
Patient/family education	PICC care; infusion technique (if self-administering); signs of treatment failure (fever, worsening pain, new weakness); when to call/return
Pharmacy/infusion arranged	Home infusion company contracted; medications delivered; pump if needed

Discharge Prescriptions Checklist

Medication	Details
IV antibiotic (specific to organism)	Dose, frequency, duration clearly documented (e.g., "Cefazolin 2g IV q8h x 6 weeks from [date]")
Oral analgesics	Acetaminophen, limited opioid PRN, gabapentin if neuropathic pain
DVT prophylaxis	Enoxaparin 40 mg SQ daily (if continuing) or transition to ambulation-based prevention
Rifampin (if applicable)	Only as adjunctive therapy; never monotherapy; document interactions
PPI / H2 blocker	If on steroids or at risk for GI bleed
Bowel regimen	If on opioids
Heparin flushes	For PICC maintenance

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8. EVIDENCE & REFERENCES

Key Guidelines

Guideline	Source	Year	Key Recommendation
Vertebral Osteomyelitis Guidelines	IDSA Clinical Practice Guideline	2015	6-week IV antibiotic duration for vertebral osteomyelitis; MRI is imaging modality of choice; surgical drainage if neurologic deficit, spinal instability, or failure of medical therapy
Spinal Epidural Abscess Management	AANS/CNS Joint Guidelines	2017	Emergent surgical decompression recommended for patients with neurologic deficit; medical management may be considered for select patients without deficit and with identified organism
Native Vertebral Osteomyelitis	British Infection Association / British Orthopaedic Association	2015	MRI within 24h; blood cultures before antibiotics; echocardiogram for S. aureus bacteremia; 6-week IV antibiotics

Landmark Studies

Study	Finding	Impact
Darouiche (2006) — NEJM Review	Comprehensive review of SEA: S. aureus most common (60-70%); pre-operative neurologic status is #1 predictor of outcome; early surgery associated with better outcomes; medical management reasonable in selected cases without deficit	Established framework for surgical vs. medical management decision-making
Siddiq et al. (2004) — Meta-analysis	915 patients: Surgical treatment associated with better neurologic outcomes than medical management alone; patients presenting with neurologic deficit benefit most from early surgery	Supports surgical decompression as preferred approach, especially with neurologic deficit
Connor et al. (2013)	Timing of surgery: decompression within 24h of neurologic deficit associated with significantly better outcomes than delayed surgery	Established 24h window for surgical decompression
Patel et al. (2014)	Risk factors for poor outcome: advanced age, diabetes, MRSA, delayed diagnosis, pre-operative paralysis, cervical/thoracic location	Identified high-risk patients who may benefit from aggressive surgical approach
Berbari et al. (2015) — IDSA Guidelines	6-week IV antibiotic duration for vertebral osteomyelitis; longer for complicated cases (endocarditis, undrained abscess); rifampin adjunct for staphylococcal infections	Standardized antibiotic duration and adjunctive therapy
OVIVA Trial (2019)	Oral antibiotics non-inferior to IV for bone/joint infections after initial IV therapy in stable patients; oral switch after 2 weeks IV	Opened possibility of early oral transition for selected patients; reduces hospitalization/OPAT burden; requires careful patient selection
Reihsaus et al. (2000)	Meta-analysis: mortality 5%; permanent paralysis 4-22%; earlier surgery and better pre-operative function = better outcomes	Established prognostic importance of pre-operative neurologic status and early intervention

Risk Factor Summary

Major Risk Factors	Prevalence in SEA
Diabetes mellitus	30-50%
Intravenous drug use (IVDU)	20-30%
Recent spinal procedure/injection	15-20%
Immunocompromised state (HIV, malignancy, steroids)	15-20%
Chronic renal failure/hemodialysis	10-15%
Alcoholism	10-15%
Distant infection source (UTI, endocarditis, skin)	30-40%
Recent bacteremia	20-30%
Spinal abnormality (prior surgery, degenerative disease)	15-20%

Microbiology

Organism	Frequency	Key Features
Staphylococcus aureus	60-70% (MRSA 30-50% of S. aureus)	Most common; hematogenous spread; IVDU, skin infection, catheters; MRSA requires vancomycin
Coagulase-negative Staphylococci	5-10%	Post-procedural; hardware-associated
Streptococci (including viridans, pneumoniae)	5-10%	Endocarditis association; dental source
Gram-negative bacilli (E. coli, Pseudomonas, Klebsiella)	10-15%	Urinary source; IVDU (Pseudomonas); diabetics
Enterococcus	2-5%	Urinary source; GI/biliary source
Anaerobes	2-5%	Often polymicrobial; abdominal/pelvic source
Mycobacterium tuberculosis	<5% (higher in endemic areas)	Subacute/chronic; Pott's disease; vertebral destruction; cold abscess; paraspinal extension
Fungi (Candida, Aspergillus)	<2%	IVDU; immunocompromised; indwelling catheters
Culture-negative	10-20%	Prior antibiotics; fastidious organisms; consider TB, Brucella, fungi

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APPENDICES

Appendix A: Surgical vs. Medical Management Algorithm

SPINAL EPIDURAL ABSCESS CONFIRMED ON MRI
                │
                ├── NEUROLOGIC DEFICIT PRESENT?
                │        (weakness, sensory level, bowel/bladder dysfunction)
                │
                │   YES → EMERGENT SURGICAL DECOMPRESSION + DRAINAGE
                │         (within 24h; within hours if rapidly progressive)
                │         + IV antibiotics
                │
                │   NO (neurologically intact) ↓
                │
                ├── OTHER SURGICAL INDICATIONS?
                │        • Sepsis/hemodynamic instability not improving
                │        • Significant spinal instability
                │        • Large abscess (>2.5-3 cm)
                │        • Unknown organism (need tissue diagnosis)
                │        • Failure of medical therapy
                │
                │   YES → SURGICAL DRAINAGE + IV antibiotics
                │
                │   NO ↓
                │
                ├── CANDIDATE FOR MEDICAL MANAGEMENT?
                │        • No neurologic deficit
                │        • Organism identified (blood cultures positive)
                │        • Small abscess
                │        • Hemodynamically stable
                │        • Able to perform serial neuro exams (reliable)
                │
                │   YES → MEDICAL MANAGEMENT (IV antibiotics)
                │         WITH:
                │         • q2-4h neurologic checks (initially)
                │         • MRI at 48-72h (assess for enlargement)
                │         • Weekly MRI until improving
                │         • LOW threshold for surgery if ANY deterioration
                │
                │   NO → SURGICAL DRAINAGE + IV antibiotics
                │
                └── MEDICAL MANAGEMENT FAILURE?
                          • Neurologic deterioration (ANY)
                          • Persistent fever >72h
                          • Enlarging abscess on imaging
                          • Persistent bacteremia
                          • Clinical worsening
                                    ↓
                          SURGICAL DRAINAGE (delayed surgery)

Appendix B: Antibiotic Selection Quick Reference

Scenario	Empiric Regimen	Duration
Standard empiric (unknown organism)	Vancomycin 15-20 mg/kg IV q8-12h + Ceftriaxone 2g IV q12h	Adjust to cultures → 6-8 weeks total
Penicillin/cephalosporin allergy	Vancomycin + Aztreonam 2g IV q8h OR Vancomycin + Fluoroquinolone	Adjust to cultures
Pseudomonas risk (IVDU, immunocompromised)	Vancomycin + Cefepime 2g IV q8h OR Vancomycin + Pip-tazo 4.5g IV q6h	Adjust to cultures
MSSA (confirmed)	Nafcillin 2g IV q4h OR Cefazolin 2g IV q8h ± Rifampin 300mg PO BID (if vertebral involvement)	6-8 weeks
MRSA (confirmed)	Vancomycin 15-20 mg/kg IV q8-12h (trough 15-20) ± Rifampin; ALT: Daptomycin 6-8 mg/kg IV daily (if no pneumonia)	6-8 weeks
Streptococci	Penicillin G 4 MU IV q4h OR Ceftriaxone 2g IV q12h	6 weeks
Enterococcus (susceptible)	Ampicillin 2g IV q4h ± Gentamicin 3mg/kg/day	6 weeks
Gram-negative (susceptible)	Ceftriaxone 2g IV q12h OR Ciprofloxacin 400mg IV q8h → PO 750mg BID	6 weeks
With endocarditis	Standard regimen for organism + extended duration (6 weeks minimum from first negative culture)	6+ weeks

Appendix C: ESR/CRP Monitoring Interpretation

Marker	Expected Trajectory	Concerning Trend	Action
CRP	Peaks early; should begin declining within 1 week; normalize by 3-4 weeks	Rising or plateau after 1 week	Repeat imaging; reassess antibiotic coverage; consider surgery
ESR	May initially rise; begins declining at 2-3 weeks; may not normalize for 6-8 weeks or longer	Rising after 3-4 weeks; failure to decline after 4 weeks	Repeat imaging; ID reassessment; consider treatment failure
WBC	Should normalize within days-1 week	Persistent leukocytosis	Evaluate for secondary site; persistent infection

NOTE: ESR is slow to change and may remain elevated for weeks after successful treatment. CRP is more responsive and useful for early treatment monitoring. Imaging may appear worse at 2-4 weeks despite clinical improvement (this is normal — abscess organization and enhancement may increase before resolution).

Appendix D: Scoring Systems

Modified MESS Score (Medical vs. Surgical Management)

Consider medical management if ALL of the following: - [ ] No neurologic deficit - [ ] Organism identified (blood cultures or biopsy positive) - [ ] Abscess ≤2.5 cm in maximum dimension - [ ] No significant spinal instability (SINS <7) - [ ] Hemodynamically stable (not septic shock) - [ ] Patient can be monitored closely (serial exams possible) - [ ] Patient is a poor surgical candidate (relative factor)

If ANY box is unchecked → strongly consider surgical drainage

SINS (Spinal Instability Neoplastic Score) — Also useful for infection

Can be applied to infectious destruction to assess instability (see MSCC template for full scoring details). SINS ≥7 suggests instability requiring surgical stabilization.

Appendix E: Post-Discharge OPAT Monitoring Checklist

Monitoring	Frequency	Parameters
ID clinic visit	Weekly	Clinical assessment, review labs, antibiotic tolerance, PICC site
CBC	Weekly	Anemia, thrombocytopenia (linezolid), leukopenia
CMP	Weekly	Renal function (vancomycin, aminoglycosides)
Vancomycin trough	Weekly (more frequent initially)	Target 15-20 mcg/mL
ESR, CRP	Weekly	Declining trend
LFTs	Weekly (if on rifampin or other hepatotoxic drugs)	Transaminases <3x ULN
PICC site assessment	Each VNA visit (2-3x/week)	No erythema, drainage, tenderness
Neurologic exam	Each ID visit; patient self-monitoring daily	Stable; no new weakness/numbness
Temperature	Patient: daily	Afebrile

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This template represents the initial build phase (Skill 1) and requires validation through the checker pipeline (Skills 2-6) before clinical deployment.