An Unusual Manifestation of a Common Bug!

Abstract

Introduction: Pseudomembranous colitis due to Clostridium difficile (C. diff) is a common cause of nosocomial diarrhea. Extra-intestinal manifestation of C. diff infection (CDI) is rare, with an incidence rate ranging between 0.6 and 1.08%. We present a case of lung abscess and empyema due to CDI in a patient without any preceding gastrointestinal symptoms or recent antibiotic use. CASE PRESENTATION: A 59 year old, obese female was brought to the emergency room for fever with severe malaise, bilateral lower extremity swelling and progressively worsening shortness of breath for 2 weeks. She reported a 40lbs weight loss. She denied chest pain, cough, sputum production, palpitation, orthopnea, paroxysmal nocturnal dyspnea, calf pain, nausea, vomiting or diarrhea. There was no sick contact, travel history, recent hospitalization or antibiotic use. She was afebrile, tachycardic (irregularly irregular) and dyspneic. Physical examination revealed reduced breath sound at the left lung base and pedal edema. Chest X ray was significant for left sided pleural effusion.Labs revealed a WBC count of 9.3 and a BNP of 3287 pg/ml. CTA chest was negative for pulmonary embolus but showed moderate left sided pleural effusion and small right sided effusion. ECHO showed an EF of 30-35%. She was treated for heart failure with partial resolution of dyspnea but no improvement of the effusion on repeat imaging. She became febrile up to 103F with worsening leukocytosis. Thoracentesis yielded 1.3L of bloody exudative pleural fluid. The fluid cytology and cultures were negative. A chest tube was inserted for persistent effusion and fever. Since all cultures were negative, she eventually underwent an open left thoracotomy and pleural decortication for empyema at which time an abscess was found. Cultures grew Clostridium difficile. She was treated with IV vancomycin and IV metronidazole with rapid clinical improvement. DISCUSSION: Most reported cases of extra-intestinal C. diff infection have been acquired as a nosocomial infection. Risk factors include health care exposure, antibiotic use, inflammatory bowel disease, GI surgery and malignancy. Common sites of infection are abdominopelvic cavity, perianal area, blood stream infection and wound infection. Brain abscess, osteomyelitis, splenic abscess, pyelonephritis and empyema have also been reported but are extremely rare. Interestingly, unlike intestinal C diff infection ,many isolated strains are non toxigenic in extra-intestinal infection. In some instances, C diff was isolated a part of poly microbial infection, mostly with other gut bacteria. Conclusions: Pulmonary infection with C. diff is extremely rare. The virulence factors that cause extra colonic infection are still unknown. To our knowledge, this is the first case of monomicrobial lung abscess due to C. diff.