Pulmonary Langerhans cell histiocytosis; characteristics of 11 cases.

Introduction: Pulmonary Langerhans cell histiocytosis (PLCH) is a rarely seen disease of younger population. Almost all of the patients were smoker. In this study we aimed to evaluate the characteristics, diagnosis, treatment modalities and prognosis of 11 cases with PLCH.

Materials And Methods: We retrospectively reviewed our case series of eleven patients who were pathologically diagnosed as PLCH. The median age was 35 years (19-51) and male to female ratio (M/F) was 5/6. All of the patients were symptomatic. The most common symptoms were dyspnea (81.8%) and dry cough (72.7%). Mean duration of the symptoms was 10.8 months. All patients except two of them were smoker (81.8%). All patients were also passive smokers.

Results: Bilateral cystic appearance (n= 9, 81.8%), interstitial findings [septal and peribronchovascular thickening (72.7%) and nodular pattern (54.5%)] were common radiological findings. Spontaneous pneumothorax was present in two cases. All patients were diagnosed with surgical biopsies (90.9%) or transbronchial parenchymal biopsy (9.1%). Smoking cessation (81.8%) and immunosupression therapy (methylprednisolone) were the treatment modalities. Mean follow-up period was 5.40 ± 1.78 years. Generally, symptoms were improved with smoking cessation or methylprednisolone therapy. One patient was readmitted to our clinic with recurrent pneumothorax. In conclusion, it should be kept in mind that passive smoking is also responsible in the pathogenesis of PLCH.

Conclusion: Exact consensus for PLCH treatment was not present except a few recommendations. In the future, with the understanding of the pathogenesis of the disease, new therapeutic agents will be discovered for this rare condition.