Diagnostic discrepancy between bronchoalveolar lavage and transbronchial biopsy from bronchoscopies of HIV patients with pneumonia: toward an integral diagnosis.

Background: The key diagnostic method for the evaluation of lung diseases associated with HIV infection is bronchoscopy, with bronchoalveolar lavage (BAL) being the most commonly used sampling technique. Transbronchial biopsy (TBB) is often complementary.

Setting: This is a retrospective cross-sectional study to determine the diagnostic usefulness of bronchoscopy with simultaneous samples obtained through BAL and TBB in HIV-infected patients with pneumonia at the National Institute of Respiratory Diseases Ismael Cosío Villegas.

Methods: In this cross-sectional study (January 2014-December 2015), the diagnostic yield of bronchoscopic samples from all HIV-positive patients with pneumonia aged >18 years, from procedures performed in the Interventional Pulmonology Unit, was analyzed and recorded in its database. The diagnostic yield concordance between BAL and TBB samples was evaluated by kappa index calculation.

Results: A total of 198 procedures on 189 HIV-infected patients with pneumonia were performed. A total of 167/189 (88.4%) patients were male, and the mean age was 34.7 years (SD ±9.0). Overall, the diagnostic yield for either technique was 87.9% (174/198), but it was higher for TBB, its yield being 78.8% (156/198). In contrast, that of BAL was 62.1% (123/198) (=0.001). The overall diagnostic yield concordance between TBB and BAL was insignificant (=0.213, <0.001). It improved for fungal infections, pneumocystosis, and tuberculosis (=0.417, 0.583, and 0.462, respectively, all <0.001).

Conclusion: Our results show that the simultaneous obtainment of BAL and TBB samples is useful and complementary in the diagnosis of infections and malignancies in HIV-infected patients. Additionally, they are safe procedures in this group of patients.