INFECTIONS IN LUNG AND HEART TRANSPLANT RECIPIENTS - Studies on the impact of bronchoscopy in the diagnosis of respiratory infections and detection of viral infections in blood and bronchoalveolar lavage fluid

Infection is a major cause of mortality and morbidity after thoracic organ transplantation. The microbiological aetiology of the infections is broad necessitating accurate diagnostic evaluation. The aim of the present study was to evaluate the infectious complications after lung and heart transplantation, with a special emphasis on the usefulness of bronchoscopy and the demonstration of cytomegalovirus (CMV), human herpes virus (HHV)-6, and HHV-7. We reviewed the diagnoses established from the specimens of all consecutive bronchoscopies performed on heart transplant recipients from May 1988 to December 2001 (n = 44) and lung transplant recipients from February 1994 to November 2002 (n = 472). To compare different assays in the detection of CMV and guiding the antiviral therapy, a total of 21 thoracic organ transplant recipients were prospectively monitored by CMV pp65-antigenemia, DNAemia (PCR), and mRNAemia (NASBA) tests. The antigenemia test was the reference assay for therapeutic intervention. In addition to CMV antigenemia, 22 lung transplant recipients were monitored for HHV-6 and HHV-7 antigenemia. The overall diagnostic yield of the clinically indicated bronchoscopies was 41 % in the heart transplant recipients and 61 % in the lung transplant recipients. The utility of the bronchoscopy was highest from one to six months after transplantation. In contrast, the findings from the surveillance bronchoscopies performed on lung transplant recipients led to a change in the previous treatment in only 6 % of the cases. Pneumocystis carinii and CMV were the most commonly detected pathogens in the bronchoscopic specimens. Furthermore, 15 (65 %) of the P. carinii infections in the lung transplant recipients were detected during adequate chemoprophylaxis. Although some complications of the bronchoscopy were detected, none of them were fatal.