Lung adenocarcinoma masquerading as refractory Klebsiella pneumoniae.

We report the case of a middle-aged man where a diagnosis of Klebsiella pneumoniae obscured the underlying malignancy. The patient was hospitalised for management of a presumed refractory community-acquired pneumonia with radiological features of right lower lobe consolidation. Bronchoscopy did not identify an endobronchial lesion and washings grew K pneumoniae. CT-guided fine-needle aspirate samples did not detect any malignancy. However, despite appropriate antibiotic treatment there was no improvement in the patient's clinical condition. Consequently, a CT-guided lung core biopsy was performed to obtain more tissue for histopathology, which was diagnostic of primary lung adenocarcinoma. This case highlights the need to continue to investigate a patient who is not progressing as clinically appropriate to their original diagnosis.