Case Based Learning for March 2025

36-year-old male patient, past medical history of asthma not taking any medications for it, presents to the ER for cc of ”body aches.” Reports myalgias, cough, shortness of breath, intermittent fevers and chills for several days. Taking Motrin and Tylenol for symptoms with temporary relief. Has sick contacts at home. Denies any other complaints at this time.

PMH: asthma
PSH: Denies
HR 134, BP 113/74, RR 22, SpO2 98%, Temp 99°F
PE: appears fatigued, tachycardia, appears fatigued, lungs clear, otherwise normal
Workup: CXR normal, viral panel negative, WBC 18.9, ANC 16.4, CO2 22
Diagnosis: Cough, back pain, shortness of breath
Plan: Discharged on doxycycline, ibuprofen, acetaminophen (ER note reports uncertain cause of infection and empiric coverage with doxycycline)

RETURN TO ER

2 days later patient presents via ambulance with cc of non-productive cough and fatigue. Patient worried he has mono as his son recently had it. Paramedics report a “sore” on the buttock. Treated 250mg fluid bolus prior to arrival
HR 130, BP 113/69, RR 23, SpO2 97% Temp 99.5°F
PE: tachycardia, lungs clear. Then taken into resusc bay for quick exam of buttocks showing 1.5cm x 1cm dark bullae to right inguinal/perineal region, no pain beyond boundaries, no crepitus, no dusky appearance of skin
DDx: most likely cellulitis, folliculitis, necrotizing soft tissue infection; less likely PNA, mono, viral
Sepsis workup and treatment initiated. Labs and cultures ordered, 30mL/kg fluid bolus, Zosyn and Vancomycin
WORKUP: WBC 15.63, H/H 13.4/38.1, CMP Na 139, Cr 1.3, Glu 127, Lactate 1.7, CRP 33.8 mg/dL, blood cultures sent
General Surgery contacted within 1 hour. Surgery planning on seeing in the morning as LRINEC score 5, WBC improving, exam only bullae to area. IVIG added to treatment regimen.

Surgery contact and taken emergently to the OR.

Total of 3 surgeries during 17 day hospitalization. Surgical cultures strep progenies, staph epi, staph lugenensis.

NECROTIZING SOFT TISSUE INFECTION: PRESENTATION, DIAGNOSIS, AND TREATMENT

Necrotizing soft tissue infection (NSTI) is a rapidly progressing infection of the skin and soft tissues that causes extensive necrosis of the fascia and subcutaneous tissue leading to severe systemic toxicity. Encompasses necrotizing fasciitis, necrotizing myositis, necrotizing cellulitis, Fournier’s Gangrene, etc. Morbidity and mortality with a rate of 20-50%.

RISK FACTORS: any impairment of skin barrier, immunosuppression, malignancy, obesity, alcoholism, pregnancy
PRESENTATION: Erythema without sharp margins, edema, , pain out of proportion to exam and pain beyond erythema, fever, crepitus, skin bullae, necrosis/ecchymosis, crepitus, insensate (late finding). “dishwater” discharge
WORKUP: Vitals, mark the border of erythema and record time with frequent reassessments, labs, no imaging needed if clinically consistent with NSTI. LRINEC Score (Laboratory Risk Indicator for Necrotizing Fasciitis) has performed poorly in external validation although surgeons may ask for it.
TREATMENT: broad spectrum antibiotics covering Gram positive, Gram negative, and anaerobics. Clindamycin for toxing suppression. IVIG if streptococcal suspected. Surgical exploration and debridement.

References: https://www.uptodate.com/contents/necrotizing-soft-tissue-infections

By Joshua Minyard, M.D.

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