Suspected Pneumocystis carinii pneumonia with a negative induced sputum examination. Is early bronchoscopy useful?

Abstract

In U.S. patients with the acquired immunodeficiency syndrome (AIDS), Pneumocystis carinii pneumonia is the most frequent AIDS-defining opportunistic infection. Sputum induction and bronchoscopy are effective techniques for obtaining specimens used to identify P. carinii although debate continues over their optimal use, specifically whether to perform bronchoscopy after a negative induced sputum examination for P. carinii. To evaluate the usefulness of bronchoscopy in this situation, we reviewed all cases of suspected P. carinii pneumonia in which sputum induction for P. carinii was performed at San Francisco General Hospital during a 4-yr period. Bronchoscopy, performed after a negative induced sputum examination, yielded a diagnosis in 50.5% of evaluations. The most frequent diagnoses were P. carinii pneumonia (192), tracheobronchial Kaposi's sarcoma (93), tuberculosis (28), and Cryptococcus neoformans pneumonia (9). Bronchoscopy provided either the only or an earlier diagnosis in 64.3% of tuberculosis cases. Bronchoscopy with BAL was free of complications, and, importantly, a negative BAL examination for P. carinii allowed physicians to discontinue empiric P. carinii pneumonia treatment in 95%. In patients with suspected P. carinii pneumonia with a negative induced sputum examination for P. carinii, early bronchoscopy with BAL should be performed.

Meta-analysis of diagnostic procedures for Pneumocystis carinii pneumonia in HIV-1-infected patients

“…A high prevalence of PCP is still found in patients who failed to respond to HAART, are noncompliant with antiretroviral and/or prophylactic regimens, or are unaware of their HIV status, or in countries with a large burden of HIV-1 infection and no access to effective antiretroviral treatment [6,50]. In these circumstances, as in the pre-HAART era, fibreoptic bronchoscopy with BAL should be performed in patients with negative induced sputum results [51].…”

“…Eleven studies were excluded because bronchoscopy with BAL was performed only in subsets of patients (usually in patients with negative induced sputum results) [6,16,46,51,[55][56][57][58][59][60][61]. Fifteen studies (seven case-control [48,[62][63][64][65][66][67] and eight retrospective and/or nonconsecutive [51,[68][69][70][71][72][73][74]) were excluded on the basis of design and/or because they did not permit direct comparison of accuracy for every individual in the sample. Three studies used a different diagnostic standard reference [52,75,76].…”

PneumocystisPneumonia in Human Immunodeficiency Virus–infected Adults and Adolescents: Current Concepts and Future Directions

“…46,47 In HIV-infected patients, microscopic visualization of BAL specimens has a reported sensitivity of 98% or greater. 48 Because bronchoscopy requires specialized personnel and equipment and carries an associated risk of complications, sputum induction with hypertonic saline, which has a diagnostic yield of 50%-90%, could be the initial procedure used to diagnose PCP. 49 The sensitivity may be lower in patients receiving aerosolized pentamidine for prophylaxis.…”

Pneumocystis jirovecii and Cytomegalovirus Co-Infection in AIDS Patients

“…Although the presence of ground-glass opacities is non-specific for PCP, their absence strongly argues against the diagnosis of PCP, and no further diagnostic testing for PCP or PCP treatment is generally warranted in these cases [3,5]. Bronchoscopy with BAL is considered as the gold standard procedure to diagnose PCP in HIV-infected patients and has a reported sensitivity of 98% or greater [6]. The sensitivity and specificity of PCR are high -however, the cut-off that should be used to differentiate between colonization and pneumocystis pneumonia was not established [5].…”