BACKGROUND: Liver abscesses remain difficult to diagnose and treat. Risk factors include diabetes mellitus, liver cirrhosis, and immunodeficiency. The majority are pyogenic, resulting from bacterial infection. Research identifies species in the Serratia genus as the cause of pyogenic liver abscesses in only 0.25% of cases and only 1 Serratia species in each case appears to have been identified. To the best of our knowledge, the present case report is the first to involve overlapping Serratia species in a single liver abscess infection that induced cardiomyopathy.

CASE REPORT: A 45-year-old woman presented to our Emergency Department (ED) for severe generalized weakness. Initial test results indicated a diagnosis of microcytic anemia, hypomagnesemia, hypokalemia, hypocalcemia, hyperglycemia, type 2 diabetes mellitus, and severe heart failure. A computed tomography scan showed a 10-cm rim-enhancing fluid collection in the right hepatic lobe. Fluid drained from the suspected abscess tested positive for Serratia marcescens and Streptococcus viridans. The patient was treated with ceftriaxone and metronidazole, which she tolerated well. The abscess decreased to less than 9.8 mm. Twenty-one weeks after discharge, the patient received a cholecystectomy. Fluid drained from the residual abscess cultured positive for a different Serratia species, S. odorifera.

CONCLUSIONS: Diabetes mellitus and acute cholecystitis were key factors in the initial infections and abscess. We also suspect this is a rare case of cardiomyopathy induced by a Serratia infection. The source of the Serratia odorifera is less certain, as it postdates placement of a percutaneous drain, raising the potential for a nosocomial infection but not precluding the possibility that both Serratia species were previously present.

Keywords: Cholecystitis, Diabetes Mellitus, Type 2, Liver Abscess, Pyogenic, Serratia Infections, Cardiomyopathies, Cholecystitis, Acute, Serratia