OBJECTIVE: Pulmonary Langerhans cell histiocytosis (PLCH) is a rare respiratory disease closely associated with smoking. The aim of the study is to know the reality of PLCH in the Catalonian population.
METHODS: We included all patients diagnosed of PLCH in 8 different Catalonian hospitals from April 2011 to December 2012. Epidemiologic, clinical, radiological, functional, diagnostic and therapeutic variables were collected, both at the beginning and at the last visit of the process.
RESULTS: Thirty two patients were included. Overall, patients were middle-aged (38 years), with no gender predominance. Most of them were smokers (71.9%). The main pulmonary function values (forced vital capacity 75.9%, forced expiratory volume in one second 68.9%, diffusing capacity of the lung for carbon monoxide 59.6%) and radiological findings (cysts 89.7%, nodules 60.3%) showed no significant changes during evolution. However, the disease progressed with a worsening lung function in 34.4% of cases. The analysis of the functional outcome (forced vital capacity, forced expiratory volume in one second, and diffusing capacity of the lung for carbon monoxide) did not reveal significant differences according to the persistence or not of smoking (P<0.05).
CONCLUSIONS: Our patients with PLCH had similar clinical and radiological characteristics to those described in other populations. The results observed regarding the relationship with smoking suggest that there may be other factors beyond smoking, which influence on the evolution of the disease. It therefore seems advisable to design prospective studies to investigate this aspect.