Abstract
BACKGROUND: Pulmonary cryptococcosis is a common fungal infection frequently seen in immunocompromised patients. Owing to its nonspecific clinical and radiographic features, the differential diagnosis with secondary tuberculosis, malignant tumor, and bacterial pneumonia is sometimes difficult. Many case reports have focused on misdiagnosis of pulmonary cryptococcosis as a malignant tumor. But to the best of our knowledge, the coexistence of pulmonary cryptococcosis and malignant tumor is rarely presented. CASE PRESENTATION: A 52-year-old immunocompetent Han Chinese woman was presented to our emergency department complaining of headache and vomiting accompanied by postural changes. She was diagnosed with pulmonary cryptococcosis according to results of laboratory tests, computed tomography, and percutaneous lung biopsy. Owing to the poor therapeutic effects of 6-month fluconazole treatment, she underwent a second percutaneous lung biopsy and was diagnosed with pulmonary cryptococcosis coexisting with adenocarcinoma. Delayed treatment of malignant tumor resulted in lymph node metastasis, higher pathologic stage, and probably poorer prognosis. CONCLUSIONS: Our patient's case serves as a reminder not to misdiagnose pulmonary cryptococcosis coexisting with adenocarcinoma.