Fiberoptic bronchoscopy and sputum examination for diagnosis of pulmonary disease in AIDS patients in Stockholm

The role of bronchoscopy in the diagnosis and treatment of pulmonary disease in HIV-infected patients

BACKGROUND

Pulmonary disease is the most common reason for presentation and the major cause of death in HIV-infected patients. There has been an evolution in the optimal approach to the investigation of a pulmonary infiltrate in HIV-infected patients since the introduction of induced sputum for the diagnosis of Pneumocystis carinii pneumonia (PCP).

AIMS

To evaluate the usefulness of flexible fibreoptic bronchoscopy (FFB), bronchoalveolar lavage (BAL), transbronchial biopsy (TBB) and bronchial brushings (BB) in the diagnosis of pulmonary disease in HIV-infected patients and to examine the effect of FFB on changes in therapy and survival.

METHODS

The histories of all HIV-infected patients referred to Fairfield Hospital for FFB between January 1990 and June 1993 were examined retrospectively.

RESULTS

Forty-two FFB were performed on 41 patients (40 male and one female). Definitive diagnoses made at FFB included Kaposi's sarcoma (KS) (n = 9), invasive aspergillosis (n = 5), PCP (n = 4), Mycobacterium avium complex (MAC) pneumonia (n = 2), cytomegalovirus (CMV) pneumonia (n = 1), Cryptococcus neoformans pneumonia (n = 1), microsporidium (n = 1) and Pseudomonas aeruginosa pneumonia (n = 1). TBB and BB did not provide a diagnosis for diseases not seen macroscopically at FFB or diagnosed by BAL. FFB findings altered diagnosis in 21/42 (50%) presentations and changed therapy in 26/42 (62%) cases.

CONCLUSIONS

FFB together with BAL altered the working diagnosis and changed therapy in a significant number of patients. TBB and BB should not be routinely performed in all patients as these procedures are of limited value in this setting.

Diagnosis of cytomegalovirus in bronchoalveolar lavage by polymerase chain reaction, in comparison with virus isolation and detection of viral antigen

Bronchoalveolar lavage (BAL) products from 52 immunocompromised patients with symptoms of pulmonary infection was examined for cytomegalovirus (CMV) by virus isolation, polymerase chain reaction (PCR) and detection of CMV antigen by immunofluorescence or immunoperoxidase staining after short-term incubation in tissue culture and directly in BAL cells. We found that PCR detected all cases positive by virus isolation (15/52 samples) and the result was obtained within 5 h. PCR detected more cases of CMV than did virus isolation (22/52 samples). Positive PCR and negative virus isolation were consistent with probable CMV infection in 3/7 patients when other clinical and laboratory parameters of CMV infection were considered. The negative predictive value of PCR was high; none of 30 patients negative by PCR developed CMV pneumonia within the subsequent 2 months. Detection of CMV antigen after short-term incubation was rapid enough to be used in clinical practice, specific (100%) and with a sensitivity of 60%. Demonstration of CMV antigen in alveolar cells was highly specific (100%) but had too low a sensitivity (26.7%) to be used as the only rapid method. Our conclusion is that a combination of PCR and detection of CMV antigen after short-term incubation and directly in alveolar cells is optimal for rapid identification of CMV.