Bronchiolitis obliterans with idiopathic organizing pneumonia. Usefulness and yield of diagnostic techniques and procedures in a series of 20 patients

OBJECTIVE: To assess retrospectively the utility and the profitableness of the diagnostic procedures and techniques in patients with idiopathic BOOP. MATERIAL AND METHODS: We studied epidemiological features, clinical manifestations, respiratory function tests, chest radiology, and other diagnostic procedures and techniques, as well as the evolution and the mortality rates in patients with histological diagnosis of idiopathic BOOP during the period 1992-1999. RESULTS: 20 patients (55% F, 45% M). Age: 64 +/- 15 years old, 50% smokers. The mean period elapsed since the beginning of the symptoms and the time of diagnosis was 51 +/- 30 days. The clinical presentation is of a subacute influenza-like illness, with fever, cough, dyspnea and crackles. The more common abnormalities were. WBC (10,949 +/- 2,6429 mm3, ESR 85 +/- 86 UI/L, LDH 309 +/- 86 UI/L. Arterial blood gas: PaO2 64 +/- 9, PaCO2 35 +/- 3 mmHg. Pulmonary function tests: VCF 81 +/- 25%, FEV1/VCF 78 +/- 17%, TLCO 74 +/- 9%, TLCO sb 77 +/- 4%. Radiological evaluation: bilateral multiple patchy alveolar opacities 75%), solitary focal lesion (15%) and interstitial opacities (10%). The bronchoscopy and BAL 10/20 (50%). Transbronchial biopsy 12/20 wit diagnosis (60%). The video assisted thoracoscopic lung biopsy 1/20 (5%) and open lung biopsy 7/20 (35%). Recurrences 8/20 (40%). Mortality rate 3/20 (15%). CONCLUSIONS: The idiopathic BOOP is a benign entity clinic inespecific, associated to hypoxemia and bilateral alveolar opacities. The transbronchial biopsy is a diagnostic procedure alternative to the open lung biopsy, in a compatible clinico-radiological context. The response to treatment is acceptable although it presents frequent exacerbations, and low mortality rate.