LAUSR

Rationale: Isolated pulmonary Langerhans cell histiocytosis (PLCH) is rare in adults. The gold standard diagnosis requires surgical lung biopsy. However, few cases have been diagnosed with transbronchial cryobiopsy (TBCB) sampling in the early stages of the disease, particularly in China. Presenting concerns: A 50-year-old man was referred for dry cough and exertional dyspnea of more than 1 week. High-resolution computed tomography (HRCT) of the chest revealed symmetric nodules and cyst lesions with upper lobe infiltrate. Further history taking indicated that he had smoked 20 cigarettes per day for more than 30 years. Therefore, PLCH was highly suspected. However, he refused surgical lung biopsy, and TBCB was attempted to complete diagnosis. Diagnosis: Emission computed tomography excluded the possibility of extrapulmonary involvements, and pathological findings supported the diagnosis of isolated PLCH. Interventions: Smoking cessation and prednisone treatment were used for patient management. Outcomes: The symptoms receded with significant improvement of chest HRCT during 2-months of follow-up. Lessons: Early diagnosis contributes to the prognosis of isolated PLCH in adults, and TBCB may be an alternative to conventional surgical lung biopsy for pathological diagnosis of PLCH.