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Pulmonary Langerhans Cell Histiocytosis

(Eosinophilic Granuloma; Pulmonary Granulomatosis X; Pulmonary Histiocytosis X; Pulmonary Langerhans' Cell Granulomatosis; Histiocytosis)


Joyce Lee

, MD, MAS, University of Colorado School of Medicine

Full review/revision Jun 2021 | Modified Sep 2022

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.

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.


About 15% of people have no symptoms and the disorder is first recognized when an imaging study of the chest is done for another reason. The remainder develop coughing, shortness of breath, fever, chest pain worsened by deep breathing, fatigue, and weight loss. Pneumothorax Pneumothorax A pneumothorax is the presence of air between the two layers of pleura (thin, transparent, two-layered membrane that covers the lungs and also lines the inside of the chest wall), resulting... read more Pneumothorax (a collapsed lung) is a common complication due to rupture of a lung cyst. It occurs in 10 to 25% of people with pulmonary Langerhans cell histiocytosis and may be the cause of the first symptoms that develop. Scarring makes the lungs stiff and impairs their ability to transfer oxygen into and out of the blood. A few people cough up blood (hemoptysis).

Some people have pain in certain parts of a bone or a pathologic bone fracture (a fracture that occurs after only a minor injury because the bone has been thinned by a disorder). A few people develop central diabetes insipidus Central Diabetes Insipidus Central diabetes insipidus is a lack of the hormone vasopressin (antidiuretic hormone) that causes excessive production of very dilute urine (polyuria). Central diabetes insipidus has several... read more when histiocytes also affect the pituitary gland in the brain. The person makes excessive amounts of urine that is dilute. People with central diabetes insipidus probably have a worse prognosis than those who do not.


  • Chest computed tomography

Chest x-rays show nodules, small thick-walled lung cysts, and other changes that are typical of pulmonary Langerhans cell histiocytosis. Computed tomography (CT) may show these changes in enough detail to establish the diagnosis. Pulmonary function testing Pulmonary Function Testing (PFT) Pulmonary function tests measure the lungs' capacity to hold air, to move air in and out, and to absorb oxygen. Pulmonary function tests are better at detecting the general type and severity... read more Pulmonary Function Testing (PFT) shows that the amount of air the lungs can hold is below normal.

If CT does not establish the diagnosis, biopsy is required.

X-rays of bones may show that they are also affected.


Drugs Mentioned In This Article

Generic Name Select Brand Names
Cyclophosphamide, Cytoxan, Neosar
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