Monitoring of cytomegalovirus reactivation in immunocompetent intensive care unit patients

Introduction: Cytomegalovirus (CMV) is a member of herpesviruses that remain latent throughout life in the nuclei of polymorphonuclear cells after primary infection. In recent studies, it has been reported that CMV reactivation may occur not only in immunocompromised patients, but also in immunocompetent intensive care unit (ICU) patients. The aim of our study was to evaluate the frequency and risk factors of CMV reactivation and the effect of reactivation on mechanical ventilation time, survival, ICU and hospital stay in CMV seropositive, immunocompetent patients admitted to the ICU. Method: Patients admitted to the medical and the surgical ICUs of our hospital were followed up daily. Data of patients who met the inclusion criteria were recorded using the Case Report/Data Registration Form. CMV IgG analysis was performed by ELISA on the 0th day of the patients' admission to the ICU. CMV DNA analysis was performed by polymerase chain reaction (PCR) from plasma samples taken from seropositive patients on days 0, 3, 7, 14, 21 and 28. Results: A total of 146 patients were included in the study. CMV reactivation was observed in 26 (17.8%) of the patients. Reactivation was found to be highest with 31% in septic shock patients and lowest with 11.5% in patients after trauma and surgery. CMV reactivation was seen at a mean of 10 ± 4.72 (3-21) days after admission to the ICU, and the median disease duration of these patients before admission to the ICU was 3 (0-73) days. As a result of multivariate analysis sepsis, APACHE II score at ICU entry and duration of treatment before ICU were found to be independent risk factors for CMV reactivation. It was shown that bacteremia and fungemia were significantly higher in the reactivation group after ICU admission (p:0.005). There was no significant difference between patients with and without CMV reactivation in the assessment of mortality, mechanical ventilation time or length of stay in the ICU and hospital. Conclusion: The incidence of CMV reactivation in immunocompetent ICU patients was 17.8%. Although a wide variety of risk factors have been reported in studies, reactivation has been described especially in adults with severe disease caused by sepsis. In our study, the reactivation rates were found to be high especially in the group diagnosed with sepsis and septic shock. It has been shown that the rates of ICU-acquired infections increase in patients with reactivation, but there is no increase in mortality, ICU and hospital stay and mechanical ventilation time. Our results may predict that CMV reactivation is only a marker for disease severity and degree of immunosuppression. Further studies are needed to identify the patient groups likely to develop CMV reactivation and to evaluate the clinical effects of reactivation in these patients. Keywords: Cytomegalovirus, CMV, reactivation, immunocompetent, intensive care unit, sepsis