ABSTRACT
Because reports of bronchiolitis obliterans organizing pneumonia [BOOP] are lacking from the Middle East, we conducted a retrospective review of all histopathologically proven cases of BOOP over a 10-year period at three tertiary care hospitals in Riyadh and describe the clinical features and outcome. Charts at the three hospitals were searched using a specific code for BOOP or cryptogenic organizing pneumonia [COP]. Lung specimens had to show histological proof of BOOP with a compatible clinical picture. Chest radiographs and high-resolution CT scans were reviewed. Twenty cases of biopsy-proven BOOP had well-documented clinical and radiographic data. There were 11 males and 9 females [mean age, 58 years; range, 42-78]. The clinical presentation of BOOP was acute or subacute pneumonia-like illness with cough [85%], fever [70%] dyspnea, [85%] and crackles [80%]. The most frequent radiological pattern was a bilateral alveolar infiltrate. The most common abnormality on pulmonary function testing [n=14] was a restrictive pattern [11 patients]. Most patients [70%] had no underlying cause [idiopathic BOOP]. Other associations included thyroid cancer, rheumatoid arthritis, syphilis and Wegner's granulomatosis. Ten patients [50%] had a complete response to steroids, 6 [30%] had a partial response and 3 [15.8%] with secondary BOOP had rapid progressive respiratory failure and died. The clinical presentation of BOOP in our patients is similar to other reported series. A favorable outcome occurs in the majority of cases. However, BOOP may occasionally be associated with a poor prognosis, particularly when associated with an underlying disease