Diffuse cystic lung disease caused by tuberculosis infection: Case series

Diffuse cystic lung disease (DCLD) is a complex disease that can be caused by various reasons. Although the chest CT scan plays a vital role in suggesting the etiology of DCLD, it is apt to lead to misdiagnosis simply based on the CT image of the lung. Here, we report a rare case of DCLD caused by tuberculosis and misdiagnosed as pulmonary Langerhans cell histiocytosis (PLCH). A 60-year-old female DCLD patient with a long-term smoking history was admitted to the hospital because of a dry cough and dyspnea, and the chest CT scan showed diffuse irregular cysts in both lungs. We considered the patient to be PLCH. To alleviate dyspnea, we chose to give her intravenous glucocorticoids. However, she developed a high fever during the use of glucocorticoids. We performed flexible bronchoscopy and bronchoalveolar lavage. Mycobacterium tuberculosis (specific sequence reads: 30) was detected in BALF. She was finally diagnosed with pulmonary tuberculosis. Tuberculosis infection is one of the rare causes of DCLD. We have discovered thirteen similar cases by searching Pubmed and Web of Science. For DCLD patients, glucocorticoids should not be used blindly unless the existence of a tuberculosis infection is ruled out. TBLB for pathology and bronchoalveolar lavage fluid (BALF) for microbiological detection are helpful for diagnosis.