Prevalence of cytomegalovirus infection among patients in an intensive care unit

Introduction

Cytomegalovirus (CMV) is a frequent cause of illness in immunosuppressed patients. Patients in intensive care units (ICUs) are exposed to immunosuppressive-related factors and are prone to develop CMV infection and disease.

Objective

To study the prevalence of active cytomegalovirus infection among patients in a general ICU.

Patients and methods

ICU patients with at least 10 days of admission without an expected death in the following 48 hours and with positive anti-CMV IgG (enzyme-linked immunosorbent assay) antibody were included. Patients with known immunosuppression (AIDS, transplantation, cancer in chemotherapy) were excluded. Blood samples for detection of pp65 antigen in a 7-day mean interval were collected. The mean Sepsis-related Organ Failure Assessment (SOFA) score was assessed weekly during the patient permanency on the study.

Results

Thirty patients with mean age of 67.9 ± 13.9 years were included, of whom 73% (22 patients) were male. The primary diagnosis in the ICU was pulmonary infection in 10 patients (33%), cardiovascular disease in six patients (20%), neurological disease in six patients (20%) and other diagnosis in eight patients (27%). The mean general SOFA score was 7. Eighty-one samples for detection of pp65 were collected, a mean of 2.7 per patient. Five patients (16.6%) showed positive antigenemia in six samples (7.4%) (one patient presented two positive samples). The six positive samples mean were 5.5 ± 6.3 cells in 300,000 cells. The mean time of the ICU stay until the first sample became positive was 30.2 days. The mean SOFA score for patients with positive antigenemia was 8.5 versus 7 in patients without CMV active infection (P = 0.28). CMV disease was recorded for one patient (pulmonary), treated with ganciclovir, although histopathologic confirmation was lacking.

Discussion

Although patients in a general ICU setting are exposed to several immunosuppressive factors, the prevalence of CMV infection based in positive antigenemia in nonimmunosuppressed patients is low when compared with other immunosuppressed patient groups.