Chronic Pneumonia Due to Klebsiella oxytoca Mimicking Pulmonary Tuberculosis

Klebsiella species infrequently cause acute community acquired pneumonia (CAP). The chronic form of the disease caused by K. pneumoniae (Friedlander's bacillus) was occasionally seen in the pre-antibiotic era. K. oxytoca is a singularly uncommon cause of CAP. The chronic form of the disease caused by K. oxytoca has been documented only once before. A 50-year-old immunocompetent male smoker presented with haemoptysis for 12 months. Imaging demonstrated a cavitary lesion in the right upper lobe with emphysematous changes. Sputum stains and cultures for Mycobacterium tuberculosis were negative. However, three sputum samples for aerobic culture as well as bronchial aspirate cultured pure growth of K. oxytoca. A diagnosis of chronic pneumonia due to K. oxytoca was established and with appropriate therapy, the patient was largely asymptomatic. The remarkable clinical and radiological similarity to pulmonary tuberculosis can result in patients with chronic Klebsiella pneumonia erroneously receiving anti-tuberculous therapy.