Pulmonary langerhans cell histiocytosis

[Mary Mallozziberg]

Pulmonary Langerhans cell histiocytosis is a disorder in which cells called histiocytes and eosinophils (types of white blood cells) proliferate in the lungs, often causing scarring.

People may have no symptoms or may cough and have difficulty breathing.
Diagnosis requires computed tomography and sometimes analysis of a sample of lung tissue (biopsy).
Whether and which treatments help are unknown, but stopping smoking may help.

(See also Overview of Idiopathic Interstitial Pneumonias.)
Langerhans cell histiocytosis can affect other organs (such as the pituitary gland, bones, and the lymph nodes) as well as the lungs. The cause is unknown, and the disorder is rare. It occurs almost exclusively in whites aged 20 to 40 who smoke cigarettes. Pulmonary Langerhans cell histiocytosis starts with infiltration of the lung by histiocytes, which are cells that scavenge for foreign materials, and to a lesser extent by eosinophils, which are cells that are normally involved in allergic reactions.