Early Lymphopenia and Infections in Nontraumatic Subarachnoid Hemorrhage Patients.

INTRODUCTION Subarachnoid hemorrhage (SAH) is associated with high morbidity and mortality. A certain degree of immunodepression has been reported during critical illness, and lymphopenia identified as an independent predictor of poor outcome; no data are available for critically ill SAH patients. We aimed to evaluate the prevalence of lymphopenia among SAH patients and its association with hospital-acquired infection. METHODS Retrospective cohort study of adult patients admitted to an intensive care unit with nontraumatic SAH between January 2011 and May 2016. Lymphocyte count was obtained daily for the first 5 days; lymphopenia was defined as lymphocyte count <1000/mm. The occurrence of infection during the first 21 days after hospital admission, hospital mortality, and unfavorable neurological outcome (Glasgow Outcome Scale score 1 to 3 at 3 mo) were recorded. RESULTS Data from 270 patients were analyzed (median age 54 y; male 45%); 121 (45%) patients had lymphopenia and 62 (23%) patients developed infections. Median (25th to 75th percentiles) lymphocyte count at hospital admission was 1280 (890 to 1977)/mm. Lymphopenia patients had more episodes of infection (38/121, 31% vs. 24/139, 17%; P=0.003) than nonlymphopenia patients, while mortality and unfavorable outcome were similar. Lymphopenia was not independently associated with the development of infection, unfavorable neurological outcome or with mortality. CONCLUSIONS Early lymphopenia is common after SAH, but is not significantly associated with the development of infections or with poor outcome.