Right Lung Consolidation Combined Elevated Serum Neuron Specific Enolase Misdiagnosed as Lung Carcinoma Ultimately Confirmed Pulmonary Cryptococcosis by CT-guided Percutaneous Lung Biopsy: a Case Report and Literature Review

BACKGROUND Detection of serum neuron specific enolase (NSE) has high sensitivity and specificity in the diagnosis of lung carcinoma, especially in small cell lung carcinoma, but sometimes serum NSE provided limited help. We report a case of a patient with right lung consolidation combined with elevated serum neuron specific enolase which mimicked lung carcinoma and was ultimately confirmed as pulmonary cryptococcosis by CT-guided percutaneous lung biopsy. METHODS Chest computed tomography (CT) scan and CT-guided percutaneous lung biopsy were performed for diagnosis and blood tests explored the latent etiology. RESULTS The chest CT scan showed right lung consolidation and a pulmonary nodule in lingual segment of upper lobe of left (Figure1A - F). Serum cryptococcal antigen was positive. Pathology of CT-guided percutaneous lung biopsy confirmed pulmonary cryptococcosis (Figure 1G - I). CONCLUSIONS Elevated NSE is not a specific index of lung cancer. Serum cryptococcal antigen and CT-guided percutaneous lung biopsy has high specificity in cryptococcal pneumonia.