Methotrexate-induced pneumonitis in a patient with Crohn's disease.

Pulmonary toxicity is a well recognised but infrequent adverse event of treatment with methotrexate. The vast majority of cases have occurred in patients with rheumatoid arthritis; here we present the case of a 44-year old woman with ileo-colonic Crohn's disease who developed methotrexate pneumonitis. The patient had a 10 year history of Crohn's disease and, in the last 18 months, she was treated with oral methotrexate because of steroid-dependency and intolerance to thiopurines. She was admitted to the hospital because of acute dyspnoea, non-productive cough and fever. High-resolution CT scan showed diffuse bilateral areas of ground-glass opacity, and pulmonary function tests disclosed a mild obstructive pattern with a decrease in carbon monoxide diffusing capacity. Blood cultures for pathogenic bacteria or fungi were negative as well as serologic tests against major pneumotropic agents. Methotrexate-induced lung injury was considered: the drug was discontinued and the patient received a steroid course with rapid symptomatic improvement. After 4 weeks pulmonary function tests and high-resolution chest CT scan were normal. To our knowledge this is the second reported case of methotrexate-induced pneumonitis occurring in a patient with Crohn's disease. A definite diagnosis has been made not invasively according to clinical, laboratory and radiological criteria and excluding any infectious aetiology of the pulmonary findings.

Methotrexate-induced pneumonitis in Crohn's disease. Case report and review of the literature.

Methotrexate (MTX) is a folate-antagonist used in several neoplastic and inflammatory diseases. Reports of pulmonary complications in patients given low-dose MTX therapy are increasing. Pulmonary toxicity from MTX has a variable frequency and can present with different forms. Most often MTX-induced pneumonia in patients affected by rheumatoid arthritis (RA) is reported.In this paper we describe a case of MTX-related pneumonitis in a relatively young woman affected by Crohn's disease who presented non-productive cough, fever and dyspnea on exercise. Chest X-ray demonstrated bilateral interstitial infiltrates and at computed tomography (CT) ground-glass opacities appeared in both lungs. At spirometry an obstructive defect was demonstrated. A rapid improvement of symptoms and the regression of radiographic and spirometric alterations was achieved through MTX withdrawal and the introduction of corticosteroid therapy.