Cryptogenic organizing pneumonia in patient with Crohn’s disease: a case report and literature review

Crohn’s disease is a chronic granulomatous illness associated with a number of extra-intestinal manifestations that may be involved with many organ systems. Cryptogenic organizing pneumonia (COP) has been considered as relatively rare extra-intestinal manifestation of Crohn’s disease. In this case, we described the whole diagnostic and therapeutic process in a Crohn’s patient with cryptogenic organizing pneumonia, reviewed articles describing such cases reported in PubMed and summarized its clinical characteristics. The main common symptoms in all 13 reported cases are dyspnea, cough, fever and chest pain. One patient just showed imaging changes without symptoms. No similar case was reported in children. The common imaging manifestations are diffuse groundglass opacities, multiple nodular consolidation or bilateral infiltrates. Majority of the patients were diagnosed as pulmonary infection and prescribed empirical antibiotics initially and ineffectively. 7 in 13 patients was received treatment with glucocorticoids, 3 with infliximab. 3 patients showed spontaneous remission. All the 13 patients had a wonderful improvement of pulmonary disease. One in 13 patients developed severe organizing pneumonia because of initiation of azathioprine. In conclusion, COP is a pulmonary interstitial disease which demands us to exclude all possible or potential factors to develop organizing pneumonia (OP) such as drugs, infection, connective tissue disease especially mesalazine, azathioprine. Clinical characteristics of cryptogenic organizing disease are extremely similar to infectious pneumonia. Sometimes, its manifestation may be respiratory failure. We deemed that combination of careful history review, evaluation of disease and lung biopsy is imperative to obtain a definite diagnosis. Moreover, physicians should be alert to asymptomatic pulmonary disease especially when Crohn’s disease remains active continually despite treatment of various medications. Corticosteroid is the standard treatment. However, treatment with infliximab infusion rituximab or macrolides may be appropriate choices when corticosteroid therapy is non-effective.