Abstract
Citrobacter koseri is a gram-negative bacillius that belongs to the Enterobacteriaceae family. It is an uncommon pathogen that typically causes meningitis and brain abscesses in children, however central nervous system (CNS) infections are rarely found in adults. We present a case of C. koseri meningitis in an immunocompetent adult secondary to intestinal micro-perforation caused by Strongyloides A 76-year-old man admitted for asthma exacerbation developed septic shock. A lumbar puncture revealed bacterial meningitis. Blood and CSF cultures grew Citrobacter koseri with identical susceptibilities, suggesting infection by one strain. Despite broad-spectrum antibiotics, the patient expired of multi-organ failure. Autopsy identified diffuse alveolar hemorrhage as the immedi ate cause of death with a heavy burden of Strongyloides stercoralis in his gastrointestinal system, lungs, and meninges. Citrobacter koseri is a gram-negative bacillus of the Enterobacteriaceae family. It is an uncommon pathogen that typically causes meningitis and brain abscesses in children. Infections in adults occur in immunocompromised hosts or instances where an insult creates a port of entry. This is the first documented case of C.koseri sepsis in an immunocompetent host associated with Strongyloides Hyperinfection Syndrome (SHS), where massive parasitic intestinal invasion reaches pulmonary circulation and perforates the alveolar membrane. This case highlights that presence of rare enterobacterial infections should prompt consideration of differentials including SHS.