Invasive non-typhoidal Salmonella in adult patients: A three-year review in a Malaysian General Hospital

Invasive non-typhoidal Salmonella (iNTS) are recognized as an important cause of infection among immunocompromised patients with high morbidity and mortality. This study focused on the epidemiology, risk factors, antibiotic susceptibility, and clinical outcome of iNTS in Hospital Kuala Lumpur over 3 years period (2017-2019). Methods: A retrospective study was conducted on 43 adult patient who had NTS isolated from a sterile sample. The patient’s microbiology worksheets and medical notes were reviewed and analyzed. Results: The overall incidence rate for iNTS was 2.4 per 10,000 admissions. The patients median age was 57 years, with majority of them being above ≥ 55 years old (n=24, 55.8%). The most prevalent diseases are hypertension (28%), human immunodeficiency virus (20.9%), diabetes mellitus (18.6%) and heart disease (6.3%). Primary bacteraemia (95.3%) was the most frequent cause of iNTS, followed by tubo-ovarian abscess (2.3%) and urinary tract infections (2.3%). The overall mortality rate was 30%. The mortality rate was greater in patient presenting with shock on admission (p=0.04). Most of the invasive diseases were caused by Salmonella enterica serovar Enteritidis (95.3%). Overall, most isolates were susceptible to ceftriaxone (97.7%). Five isolates were intermediately resistant to ciprofloxacin (11.6%). Only one isolate (2.3%) was multidrug resistant. Conclusions: The comorbidities of iNTS varies even within the same country. Mortality rates are higher in those with primary bacteraemia and shock during admission. By understanding the epidemiology of iNTS in Malaysia, it will provide valuable information about the vulnerable population at risk of iNTS and improve the treatment and management of this patients.