Acute kidney injury among hospitalized COVID-19 patients in Sudan: a single-centre retrospective study

Acute kidney injury (AKI) is a common complication of COVID-19 and may lead to persistent kidney dysfunction. Little is known about Sudan. This study aimed to assess the incidence, clinical characteristics, and outcomes of AKI among COVID-19 patients in tertiary hospital settings.

We retrospectively evaluated 868 of 990 adults with confirmed COVID-19 admitted to a Khartoum Teaching Hospital's COVID-19 isolation center, Khartoum, Sudan in 2021. Patients on maintenance dialysis or with incomplete core data were excluded. AKI was defined was defined using Kidney Disease Improving Global Outcomes criteria and staged according to Risk, Injury, Failure, Loss, and End-stage renal disease criteria. Outcomes included in-hospital mortality and renal status at discharge. Comparisons used chi-square tests, and multivariable logistic regression identified independent predictors of survival.

AKI occurred in 46% of hospitalized patients, mainly older males with hypertension or diabetes. The severity ranged widely. In-hospital mortality was 69%, and renal recovery among survivors was frequently incomplete. Multivariable analysis showed that increasing age (adjusted OR 0.970 per year), elevated D-dimer (adjusted OR 0.834 per µg/mL), and requirement for mechanical ventilation (adjusted OR 0.101) were independently associated with lower survival, whereas admission creatinine, urea, and nephrotoxin exposure were not independent predictors.

COVID-19-associated AKI was common and linked with high mortality and incomplete renal recovery. Early risk stratification using age and D-dimer, close renal monitoring, and strengthened critical care and dialysis capacity are essential in resource-limited settings. Prospective multicenter studies are needed to refine risk prediction and optimize management strategies.