Marek A Martynowicz, MD(*) and Udaya BS Prakash, MD. Pulmonary & Critical Care Medicine, Mayo Clinic & Foundation, Rochester, MN.
PURPOSE: To define clinical value and sensitivity of various techniques used for the diagnosis of pulmonary blastomycosis we 1) analyzed the use of specimens obtained from extrapulmonary sites, pulmonary specimens obtained non-invasively (sputum, gastric washings, tracheal secretions), and pulmonary specimens obtained invasively (bronchoscopy, transthoracic needle aspiration [TTNA], open lung biopsy [OLB]); and 2) compared diagnostic yields of the above techniques, including the analysis of specific bronchoscopic approaches (bronchial washings, bronchoalveolar lavage [BAL], protected speciment brush [PSB], bronchial brush, transbronchial biopsy [TBB], transbronchial needle aspiration [TBNA]).
METHODS: Retrospective chart review of all patients diagnosed with blastomycosis at the Mayo Clinic Rochester between 1967 and 1998.
RESULTS: 63 patients with pulmonary blastomyeosis were identified. In 8 patients (13%), diagnosis was based on Blastomyces dermatidis recovered from an extrapulmonary site (skin and bone in 5 and 3 patients, respectively) accompanied by a compatible chest radiograph. In 35 (56%) patients a pulmonary specimen obtained non-invasively provided the diagnosis (sputum, gastric washings and tracheal secretions in 25, 7 and 4 patients, respectively). In 20 patients (32%) a pulmonary specimen obtained invasively was the only source for the diagnosis (bronchoscopy, TTNA and OLB in 13, 1 and 6 patients, respectively). Diagnostic yield of the modalities used was as follows: sputum culture 25 of 28 (89%); gastric washings culture 7 of 8 (88%); tracheal secretions culture 4 of 5 (80%); bronchial washings 18 of 19 (95%); BAL 5 of 7 (71%); PSB 5 of 5 (100%); bronchial brush 2 of 8 (25%); TBB 4 of 10 (40%); TBNA 0 of 1 (0%); TTNA 1 of 3 (33%); OLB 11 of 12 (92%).
CONCLUSION: In majority of patients diagnosis of pulmonary blastomycosis was made without utilization of an invasive thoracic procedure (56%) or based on the recovery of B. dermatidis from an extrapulmonary site and compatible chest radiographs (13%). Among bronchoscopic procedures, yields of bronchial washings and PSB tended to be superior to BAL. Bronchoscopic cytological and histologic specimens had a poor diagnostic yield.
CLINICAL IMPLICATIONS: If pulmonary blastomyeosis is a clinical consideration sputum, gastric washings and/or tracheal secretions should be collected for cultures. If bronchoscopy is performed, bronchial washings and PSB are the preferred diagnostic specimens.
COPYRIGHT 2000 American College of Chest Physicians
COPYRIGHT 2001 Gale Group