Pulmonary cryptococcosis misdiagnosed as lung cancer in a man with normal immune function: A case report.

Pulmonary cryptococcosis is an opportunistic infection of cryptococcus both in immunocompetent and immunocompromised patients, who suffered from HIV infection, organ transplantation, diabetes mellitus, corticosteroid or immunosuppressive therapy, and malignancy. Pulmonary cryptococcosis is the commonest location of non-central nervous system cryptococcosis and usually presents with nonspecific symptoms. It often shows shadows on the lung, which makes it difficult to distinguish it from lung cancer. Here we report a case of a 52-year-old man with pulmonary cryptococcosis, who was misdiagnosed as lung cancer. Clinicians need to consider the possibility of pulmonary cryptococcosis and the importance of lung biopsy when treating a patient with a normal immune function that has isolated pulmonary nodules. This case also indirectly illustrates the importance of percutaneous lung biopsy in patients with isolated pulmonary nodules.