Outcomes of infection in adult cancer and non-cancer patients hospitalised in a tertiary hospital: a prospective cohort study.

Background: infection (CDI) is one of the most common healthcare-associated (HA) infections. Cancer patients, particularly haemato-oncological patients, have an increased risk for CDI due to more risk factors compared with non-cancer patients. The aim of this study was to investigate differences in outcomes associated with HA CDI in patients with solid and haematological malignancies compared with patients with no underlying malignant disease in a tertiary healthcare centre in Serbia.

Methods: A prospective cohort study was conducted including adult patients diagnosed with an initial episode of HA CDI. Their demographic and clinical characteristics associated with risk factors for CDI were documented. Outcomes such as all-cause 30-day mortality, cure of infection, diarrhoea relaps and recurrence of disease were followed. Patients were assigned to cancer and non-cancer groups. Within the cancer group, patients were divided into the solid tumour subgroup and haematological malignancy subgroup.

Results: During a 7-year period, HA CDI was observed in 28 (5.1%) patients with haematological malignancy, 101 (18.3%) patients with solid tumours and 424 (76.7%) non-cancer patients. Older age (OR 1.04, 95% CI 1.02 to 1.07, p<0.001), admission to the intensive care unit (ICU) (OR 2.61, 95% CI 1.37 to 4.95, p=0.003), mechanical ventilation (OR 5.19, 95% CI 2.78 to 9.71, p<0.001) and use of antibiotics prior to CDI (OR 1.04, 95% CI 1.02 to 1.06, p=0.02) were associated with increased mortality. Compared with patients with solid tumours, patients with haematological malignancy were younger (65 vs 57 years, p=0.015), did not require ICU admission (25.0% vs 0%) or mechanical ventilation (8.9% vs 0%) and were treated longer with antibiotics prior to CDI (14 vs 24 days, p=0.002).

Conclusions: Patients with haematological malignancy were exposed to different risk factors for CDI associated with mortality compared with patients with solid tumours and non-cancer patients. Older age, ICU stay and mechanical ventilation, but not presence or type of cancer, predicted the all-cause 30-day mortality.