Pandemic influenza A(H1N1) virus infection in solid organ transplant recipients: impact of viral and non‐viral co‐infection

Clin Microbiol Infect 2012; 18: 67–73 ABSTRACT: Solid organ transplant recipients (SOTR) are at risk of serious influenza‐related complications. The impact of respiratory co‐infection in SOTR with 2009 pandemic influenza A(H1N1) is unknown. A multicentre prospective study of consecutive cases of pandemic influenza A(H1N1) in SOTR was carried out to assess the clinical characteristics and outcome and the risk factors for co‐infection. Overall, 51 patients were included. Median time from transplant was 3.7 years, 5.9% of the cases occurred perioperatively and 7.8% were hospital‐acquired. Pneumonia was diagnosed in 15 (29.4%) patients. Ten cases were severe (19.6%): 13.7% were admitted to intensive care units, 5.9% suffered septic shock, 5.9% developed acute graft rejection and 7.8% died. Co‐infection was detected in 15 patients (29.4%): eight viral, six bacterial and one fungal. Viral co‐infection did not affect the outcome. Patients with non‐viral co‐infection had a worse outcome: longer hospital stay (26.2 ± 20.7 vs. 5.5 ± 10.2) and higher rate of severe diseases (85.7% vs. 2.3%) and mortality (42.8% vs. 2.3%). Independent risk factors for non‐viral co‐infection were: diabetes mellitus and septic shock. Other factors associated with severe influenza were: delayed antiviral therapy, diabetes mellitus, time since transplantation <90 days and pneumonia. In conclusion, pandemic influenza A can cause significant direct and indirect effects in SOTR, especially in the early post‐transplant period, and should be treated early. Clinicians should be aware of the possibility of non‐viral co‐infection, mainly in diabetic patients and severe cases. An effort should be made to prevent influenza with immunization of the patient and the environment.