A single season prospective study of respiratory viral infections in lung transplant recipients

¹ Dept of Medicine; and the Vanderbilt transplant Center
² Dept of Medicine
³ Dept of Surgery
⁴ the Clinical Virology laboroatory, Vanderbilt University Hospital, Vanderbilt University School of Medicine, nashville TN 37232
⁵ Dept of Surgery; and the Vanderbilt transplant Center
⁶ Depts of Medicine; Surgery; and the Vanderbilt transplant Center

^* To whom correspondence should be addressed. E-mail: stephen.Dummer{at}Vanderbilt.edu.

	Abstract

Respiratory viruses cause serious infections in lung transplant recipients, but only retrospective studies are available. Our objective was to prospectively study the frequency and complications of respiratory viral infections in an ambulatory lung transplant population during a single winter season using multiple diagnostic tests, including viral antigens, viral cultures and PCR of nasal washes (NW) or bronchoalveolar lavages (BAL).

Fifty lung transplant recipients were followed for respiratory viral infection from November through March. Serum was obtained at enrollment and one month after study conclusion. Patients were interviewed weekly. Forty nine episodes of respiratory symptoms in 32 patients prompted either NW (n=44) or BAL (n=5), which were evaluated by viral culture and PCR for respiratory syncytial virus (RSV) A&B, influenza (FLU) A&B, parainfluenza virus (PIV) 1,2 & 3. Viral antigens were performed for RSV and FLU. Sera were assayed for RSV (ELISA) and FLU (kinetic ELISA) antibodies. Patients' survival and the occurrence of acute rejection and bronchiolitis obliterans (BO) or bronchiolitis obliterans syndrome (BOS) were monitored for one year after the end of the study.

Thirty-two (64%) of the 50 study patients had NW or BAL studied for respiratory viruses. Documented infections included eight due to RSV (1 culture, 5 PCR and 7 serological), one due to PIV (culture and PCR) and ten due to FLU (3 culture, 4 PCR and 8 serological). Four patients had serological rises to FLU without reporting symptoms. Overall 17 patients (34%) had viral infection, since two had both RSV and FLU. Four patients had lower respiratory involvement and two patients (1 RSV, 1 PIV) were hospitalized for aerosolized ribavirin treatment. No patient required mechanical ventilation or died within 90 days. After one-year there were three deaths (6%), unrelated to respiratory virus infection and BO or BOS had occurred in 1/17 (6%) patients with respiratory viral infection and 3/33 (12%) without respiratory viral infection.

Respiratory viruses infected a third of ambulatory lung transplant recipients in a single season - a rate that is much higher than previously reported. Most patients on study had good outcomes, but two (12%) infected patients were hospitalized. We could not document an association between respiratory viral infection and subsequent BO or BOS. Larger prospective studies will be required to define the acute and long-term morbidity of these infections and why some patients have minor disease and others progress to more serious complications.

This article has been cited by other articles:

				K. F. Remund, M. Best, and J. J. Egan Infections Relevant to Lung Transplantation Proceedings of the ATS, January 15, 2009; 6(1): 94 - 100. [Abstract] [Full Text] [PDF]

				P. Hopkins, K. McNeil, F. Kermeen, M. Musk, E. McQueen, I. Mackay, T. Sloots, and M. Nissen Human Metapneumovirus in Lung Transplant Recipients and Comparison to Respiratory Syncytial Virus Am. J. Respir. Crit. Care Med., October 15, 2008; 178(8): 876 - 881. [Abstract] [Full Text] [PDF]