Necrobiotic nodules: a rare pulmonary manifestion of Crohn's disease

Coexistent pulmonary granulomatosis with polyangiitis (Wegener granulomatosis) and Crohn disease

Crohn disease (CD) may be associated with various extraintestinal manifestations, including, rarely, respiratory tract involvement. When necrobiotic pulmonary nodules are present, the differential diagnosis includes granulomatosis with polyangiitis (Wegener granulomatosis) (GPA). The respiratory tract manifestations of CD and GPA may mimic each other, complicating the diagnosis and suggesting the possible coexistence of these 2 conditions. The aim of this study was to describe the clinical, radiographic, and pathologic features of patients in whom CD and GPA coexist. We reviewed the teaching files of the authors and searched the Mayo Clinic medical records for coexistent inflammatory bowel diseases and antineutrophilic cytoplasmic antibodies (ANCA)-associated vasculitides. We reviewed in detail 97 patient charts and excluded cases of ulcerative colitis and those in whom only one of the diagnoses was present. Pulmonary and gastrointestinal biopsies were reviewed when available. We also searched the medical literature for previously published cases. We found 6 cases of coexistent CD and pulmonary GPA and 4 cases with extrapulmonary GPA; 3 cases (all with extrapulmonary GPA) have been published previously. The diagnosis of CD preceded that of GPA in 11 cases. Proteinase 3-ANCA was positive in 6 cases, negative in 2, and not reported in 5 cases. Myeloperoxidase-ANCA was negative in 6 cases and unavailable in the remainder of patients. Pathology revealed features diagnostic of GPA in all cases with necrotizing granulomatous inflammation and segmental vasculitis. Pulmonary findings in patients with CD or the presence of granulomatous colitis in patients with GPA should prompt the inclusion in the differential diagnosis of a possible coexistence of CD and GPA.

[Boundaries of the lung - Relationship to the gastrointestinal system]

The relation between the respiratory and gastrointestinal systems has been long recognized and depends on various anatomical, physiological and pathological mechanisms. The certain recognition of some interactions, such as the relation between asthma and gastroesophageal reflux, is more or less intuitive to the pulmonogist, whereas other areas of confluence are more easily missed, such as the relation between airway disorders and inflammatory bowel disease. The purpose of this article is to review the interaction between the lung and the gastrointestinal systems, as far as anatomy, physiology, pathology, clinical manifestations and therapeutical options go.

Vasculitis

Vasculitic syndromes involving the lung present a unique challenge for pathologists because of the histologic overlap with other disorders and the clinical implications of the diagnosis in regard to clinical management. This article reviews the more common vasculitic syndromes involving the lung, concentrating primarily on Wegener granulomatosis, Churg-Strauss syndrome, necrotizing sarcoid, microscopic polyangiitis, and diffuse alveolar hemorrhage syndromes. The article focuses on a review of the recent literature, diagnostic approach, and differential diagnosis.

Pulmonary abnormalities in inflammatory bowel disease

Extraintestinal manifestations of inflammatory bowel disease (IBD) is a common clinical problem affecting up to half of all IBD patients; pulmonary disease, however, ranks among less common extraintestinal manifestations of IBD. Pulmonary disease in patients with IBD is most frequently drug induced due to treatment with sulfasalazine or mesalamine leading to eosinophilic pneumonia and fibrosing alveolitis or due to treatment with methotrexate leading to pneumonitis. Recently, various opportunistic infections have been shown to be a further important cause of pulmonary abnormalities in those IBD patients who are treated with immunosuppressants such as anti TNF-α monoclonal antibodies, methotrexate, azathioprine or calcineurin antagonists. In not drug related pulmonary disease a wide spectrum of disease entities ranging from small and large airway dysfunction to obstructive and interstitial lung disorders exist. Patients with lung disorders and inflammatory bowel disease should be evaluated for drug-induced lung disease and opportunistic infections prior to considering pulmonary disease as an extraintestinal manifestation of inflammatory bowel disease.

Thoracic manifestations of inflammatory bowel disease

BACKGROUND

A growing number of case reports suggest that pulmonary disease occurs in association with inflammatory bowel disease (IBD) more frequently than previously recognized. Screening studies have also identified pulmonary abnormalities in a significant proportion of IBD patients.

METHODS

A focused literature review of respiratory abnormalities in IBD patients and 55 English-language case series documenting 171 instances of respiratory pathology in 155 patients with known IBD.

RESULTS

Screening studies using respiratory symptoms, high-resolution CT, and pulmonary function testing support a high prevalence of respiratory abnormalities among patients with IBD. Case reports and series document a spectrum of respiratory system involvement that spans from larynx to pleura, with bronchiectasis as the single most common disorder. IBD patients have a threefold risk of venous thromboembolism, and recent investigations have also revealed possible ties between IBD and other diseases involving the respiratory system, including sarcoidosis, asthma, and alpha(1)-antitrypsin deficiency.

CONCLUSION

Respiratory symptoms and diagnosed respiratory system disorders are more common among patients with IBD than generally appreciated. The spectrum of respiratory disorders occurring among patients with IBD is very broad. Diseases of the large airways are the most common form of involvement, with bronchiectasis being the most frequently reported form of IBD-associated lung disease.