Risk of Recurrent Nontyphoid Salmonella Bacteremia in Human Immunodeficiency Virus-infected Patients with Short-term Secondary Prophylaxis in the Era of Combination Antiretroviral Therapy

Background/purpose: Nontyphoid Salmonella (NTS) bacteremia causes high mortality and recurrence rates in human immunodeficiency virus (HIV)-infected patients. This study aimed to investigate the risk of recurrent NTS bacteremia in the era of combination antiretroviral therapy (cART).

Methods: The medical records of consecutive HIV-infected patients with NTS bacteremia from January 2006 to June 2014 were reviewed. The patients were divided into two groups: patients who achieved a decline of plasma HIV RNA load by ≥ 2 log after 4 weeks of cART (good short-term virological response) and those who failed to achieve the goal (poor short-term virological response). Clinical information was collected on the demographics, immunological and virological responses, prophylactic antibiotics used, episodes of recurrent NTS bacteremia, and mortality.

Results: During the study period, 49 patients with 52 episodes of NTS bacteremia were included: 29 patients in the good virological response group, in which 16 received secondary prophylaxis; and 20 patients in the poor response group, in which 15 received secondary prophylaxis. There were no recurrent episodes of NTS bacteremia in the good-response group, whereas the incidence rate of recurrent NTS bacteremia was 5.21 per 100 person-years and 56.42 per 100 person-years of follow-up in patients receiving and not receiving prophylaxis, respectively, in the poor-response group. No patients died in the good-response group, whereas five patients (25%) in the poor-response group died. The resistance rate of 52 NTS isolates tested to ciprofloxacin was 7.7%.

Conclusion: The risk of recurrent NTS bacteremia is low in HIV-infected patients who achieve short-term virological response to cART, regardless of secondary prophylaxis.