[Clinicopathological analysis of primary pulmonary cryptococcosis]

To investigate the clinicopathological and CT features of primary pulmonary cryptococcosis (PC), and its underlying reasons for misdiagnosis.

The clinical data and pathological features of 52 cases of PC in Zhongshan Hospital from 1998 to 2008 were retrospectively reviewed.

The 52 patients consisted of 36 males and 16 females aged from 17 to 80 years, with a median age of 48. The early symptoms were cough, phlegm and chest pain. Thirteen cases had a history of chronic diseases or malignant tumor or liver transplantation, including liver cancer and transplantation (n = 2), diabetes (n = 2), chronic hepatitis (n = 2), pituitary adenoma (n = 1), sarcoidosis (n = 1), diabetes concomitant with liver cancer and tuberculosis (n = 1), with tuberculous pleurisy (n = 1) and with hypertension (n = 1). Pulmonary nodules, either solitary or multiple, were the most common CT findings, present in 37 of the 45 cases. Cavitation was found in 4 cases, lobar consolidations in 3 cases, diffuse mixed pattern in 1 case. The CT diagnosis before surgery included malignant tumor (n = 27), pneumonia (n = 15) or tuberculosis (n = 3). Microscopically, cryptococcosis granuloma formation was found in 49 of the 52 cases, and the other 3 showed fibrosis with fungi. Cryptococcosis neoformans was detected in all the cases by mucicarmine and Grocott histopathological examination.

Chest CT findings of PC in immunocompetent patients show a predominant pattern of localized and mixed lesions. PC does not have any specific clinical manifestations and image findings, and it is difficult to be differentiated from lung cancer, tuberculosis or pneumonia. The correct diagnosis relies on histopathological examination. CT guided percutaneous biopsy is useful in confirming the diagnosis.