Clinical implications of respiratory virus infections in solid organ transplant recipients: a prospective study.

López-Medrano, Francisco; Aguado, Jose M; Lizasoain, Manuel; Folgueira, Dolores; Juan, Rafael San; Díaz-Pedroche, Carmen; Lumbreras, Carlos; Morales, Jose M; Delgado, Juan F; Moreno-González, Enrique

BACKGROUND There is limited information about clinical consequences of respiratory virus infections (RVI) in solid organ transplant recipients. No prospective epidemiological study has been published previously. METHODS We selected a cohort of 152 transplant recipients (cardiac, hepatic and renal transplant recipients). Median time from transplantation was 17 months (range 1-50). They were prospectively followed-up for RVI during 7 months (October to April). Clinical and microbiological evaluation (cell culture, shell vial and polymerase chain reaction technique) of each RVI episode was made. RESULTS We detected 81 RVI (0.91 episodes/patient/year). Complications were detected in 15/81 episodes (18.5%): acute bronchitis (10 cases), pneumonia (three cases; 3.7% of RVI episodes) and bacterial sinusitis (2 cases). In 4 of 81 episodes (5%), patients needed hospitalization. A respiratory virus was isolated in 17 of 68 nasopharyngeal samples (six respiratory syncytial virus, six influenza, four picornavirus, one adenovirus). Fever presented an 83% positive predictive value for the diagnosis of influenza virus infection among those with a positive microbiological isolation. There were no episodes of acute rejection coincidentally with RVI. Only 54% of the subjects had been previously vaccinated against influenza. CONCLUSIONS Incidence of RVI among solid organ transplant recipients is similar to general population but complications are higher. A relationship between RVI and rejection was not detected. The rate of influenza vaccination was lower than expected. The presence of fever in a transplant recipient with RVI strongly suggests influenza infection.