SESSION TYPE: Infectious Disease Student/Resident Case Report Posters I
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Serratia marcescens rarely causes pulmonary cavitations. We describe a case of Serratia induced cavitations, likely due to embolization in the setting of intravenous drug use.
CASE PRESENTATION: A 34-year-old cachectic male, active intravenous drug user, presented in diabetic ketoacidosis (DKA). History was significant for chronic nonproductive cough without sick contacts, fevers, or night sweats. Physical examination revealed injection track marks and multiple skin abscesses over bilateral antecubital fossae. Laboratory data showed leukocyte count of 12,800/μl with neutrophils - 90.6%. Chest X-ray demonstrated a right upper lobe mass and pulmonary nodules (Figure 1). Further testing revealed a negative HIV-ELISA, c-ANCA, and p-ANCA. Computed tomography (CT) chest revealed multiple bilateral infiltrates with central cavitation (Figure 2A, B). He was treated for DKA, and started on empiric antibiotics. The skin abscess wound culture grew S. marcescens. A fine needle aspiration (FNA) of a prominent cavitation showed an inflammatory infiltrate while the pleural fluid grew S. marcescens. Trans-thoracic (TTE) and trans-esophageal echocardiograms (TEE) were negative for vegetations. After being treated with cefepime, he was transtioned to trimethoprim/sulfamethoxazole upon discharge for an additional 3 weeks.
DISCUSSION: Serratia marcescens pneumonia can be rarely associated with microabscesses and large cavitations . When seen in an intravenous drug user, scattered pulmonary infiltrates with cavitation are highly suggestive of septic pulmonary emboli from right-sided infective endocarditis (IE). Septic pulmonary emboli manifest as cavitations on CT in up to 85% of patients . S. marcescens has been been associated with septic arthritis and osteomyelitis in heroin abusers but not septic pulmonary emboli in the absence of an endogenous source of infection. The seeding of the lungs with septic foci generally occurs from an endogenous site such as IE. Uniquely, our patient had septic pulmonary embolization due to S. marcescens in the absence of any obvious evidence of IE by culture, TTE or TEE. Whether a repeat TEE was required later can be debated. Therefore, this case poses a diagnostic and therapuetic challenge.
CONCLUSIONS: Skin abscesses due to S. marcescens, which could be seen in intravenous drug users, may lead to pulmonary cavitations due to septic embolization. The absence of an obvious endogenous nidus for embolization was the highlight of this case.
1) Goldstein JD, Godleski JJ, Balikian JP, Herman PG. Pathologic patterns of Serratia marcescens pneumonia. Human Pathology. 1982;13(5):479-484.
2) Cook RJ, Ashton RW, Aughenbaugh GL, Ryu JH. Septic pulmonary embolism: presenting features and clinical course of 14 patients. Chest. 2005 Jul;128(1):162-6.
DISCLOSURE: The following authors have nothing to disclose: Ranjit Joseph, Anupam Kumar, Shine Raju, Guru Trikudanathan, Patrick Troy
No Product/Research Disclosure InformationUConn Health Center, Farmington, CT