Pulmonary lymphangioleiomyomatosis: analysis of disease manifestation by region-based quantification of lung parenchyma.

PURPOSE: Lymphangioleiomyomatosis (LAM) is characterized by proliferation of smooth muscle tissue that causes bronchial obstruction and secondary cystic destruction of lung parenchyma. The aim of this study was to evaluate the typical distribution of cystic defects in LAM with quantitative volumetric chest computed tomography (CT). MATERIALS AND METHODS: CT examinations of 20 patients with confirmed LAM were evaluated with region-based quantification of lung parenchyma. Additionally, 10 consecutive patients were identified who had recently undergone CT imaging of the lung at our institution, in which no pathologies of the lung were found, to serve as a control group. Each lung was divided into three regions (upper, middle and lower thirds) with identical number of slices. In addition, we defined a "peel" and "core" of the lung comprising the 2 cm subpleural space and the remaining inner lung area. Computerized detection of lung volume and relative emphysema was performed with the PULMO 3D software (v3.42, Fraunhofer MEVIS, Bremen, Germany). This software package enables the quantification of emphysematous lung parenchyma by calculating the pixel index, which is defined as the ratio of lung voxels with a density <-950HU to the total number of voxels in the lung. RESULTS: Cystic changes accounted for 0.1-39.1% of the total lung volume in patients with LAM. Disease manifestation in the central lung was significantly higher than in peripheral areas (peel median: 15.1%, core median: 20.5%; p=0.001). Lower thirds of lung parenchyma showed significantly less cystic changes than upper and middle lung areas combined (lower third: median 13.4, upper and middle thirds: median 19.0, p=0.001). CONCLUSION: The distribution of cystic lesions in LAM is significantly more pronounced in the central lung compared to peripheral areas. There is a significant predominance of cystic changes in apical and intermediate lung zones compared to the lung bases.

Granulomatous gastritis in Wegener's disease: differentiation from Crohn's disease supported by a positive test for antineutrophil antibodies.

BACKGROUND: This report concerns the gastric manifestation of Wegener's granulomatosis in a 44 year old white female patient who initially presented with abdominal pain, vomiting, and iridocyclitis. FINDINGS: The clinical findings and the histopathological proof of granulomatous gastritis in the absence of necrotising vasculitis were initially considered to be indicative of a diagnosis of Crohn's disease showing isolated gastric involvement. A five month course of steroids resulted in temporary relief; thereafter the patient developed severe rhinitis with mucosal ulcerations. At this point biopsy of nasal mucosa disclosed the classic histopathological signs of Wegener's granulomatosis. A positive test for antineutrophil cytoplasmic antibodies (ANCAs) with a cytoplasmic pattern (c-ANCA) and antigenic specificity for proteinase 3 (PR-3) were found. The patient is in complete remission one year after diagnosis and treatment with steroids and cyclophosphamide. CONCLUSIONS: Wegener's granulomatosis can also involve the gastrointestinal tract. Granulomatous inflammation of the stomach, although a rare finding and non-specific, should include Wegener's disease in the differential diagnosis. The histological proof of necrotising vasculitis is dependent on the depth of the biopsy and therefore can be easily missed. Differential diagnosis can be clarified by ANCA testing.