Pulmonary Langerhans cell histiocytosis with thyroid involvement manifesting as recurrent bilateral pneumothorax and tension bullae in a 3-year-old child

INTRODUCTION: Pulmonary Langerhans cell histiocytosis (PLCH) is a well known entity in adults but is exceedingly rare in children. The main complication of PLCH is the occurrence of pneumothorax (PTX) and tension bullae with subsequent recurrence and persistence despite conservative management. CASE PRESENTATION: A 3-year-old child was diagnosed with PLCH with thyroid involvement. Chemotherapy was immediately initiated and continued with chest tube drainage for repeated bilateral PTX. Tension bullae developed in the right lung 1 month after initiating treatment. Emergency resection of the bullae and ligation of pulmonary cysts were performed. On the tenth postoperative day, she developed a tension bulla in the left lung. Emergency thoracotomy was performed. On the tenth postoperative day, chest X-ray and CT suggested return of the right bulla and mediastinal shift, and reoperation was performed. Repeated lung biopsy showed no sign of active LCH. Although her condition improved after the operation, subsequent repeated PTXs occurred and were difficult to treat. She was discharged home after four months. Currently, she is receiving maintenance therapy as an outpatient. During the 12-month follow-up, the pulmonary lesions also showed a tendency for improvement. DISCUSSION: Although it is difficult to treat recurrent PTX and tension bullae in advanced PLCH, continuous treatment of the primary disease (LCH) and the complications of pulmonary lesions can improve prognosis. CONCLUSION: Treatment of PLCH accompanied by recurrent PTX and tension bullae is challenging. The condition can be resolved by treating the primary disease in parallel with combined modality treatment, including surgical operation for complications.