Diagnosis of Acute Kidney Injury in Children Hospitalized in a Sub-Saharan African Unit by Saliva Urea Nitrogen Dipstick Test.

INTRODUCTION: Acute kidney injury in pediatric patients (pAKI) is common in developing countries and leads to significant morbidity and mortality. Most nephrology services in developing countries are only in larger cities and for that reason many cases remain undiagnosed. We evaluated the performance of a saliva urea nitrogen (SUN) dipstick to diagnose pAKI in Sudan. METHODS: We collected demographic and clinical information, serum creatinine (SCr), blood urea nitrogen (BUN), SUN, and urine output (UO) in children with pAKI. pAKI was diagnosed based on different criteria (Risk, Injury, Failure, Loss of kidney function, and end-stage kidney disease, Acute Kidney Injury Network and Kidney Disease Improving Global Outcomes). We also recorded hospital and 3-months' mortality and progression to chronic kidney disease (CKD) as outcomes. RESULTS: We studied 81 patients (mean age 10.7 ± 7 years, 51.9% females) and divided them by age into (a) neonates (<120 days; n = 21; 25.9%); (b) -infants (120-365 days; n = 18; 25.9%); and (c) children (>365 days; n = 42; 53.1%). Diagnosis using different pAKI definitions resulted in differences in AKI staging. SUN reliably reflected BUN over the entire study period, regardless of treatment modality or pAKI severity. Neither pAKI staging, SUN, BUN, nor SCr were associated with mortality or progression to CKD. UO predicted all-cause mortality during the 3-months follow-up. CONCLUSION: Diagnosis of pAKI using different criteria differs in triage and staging. SUN reflects BUN particularly at higher BUN levels and allows monitoring of treatment responses. Despite the lack of predictive power of SUN to predict hard outcomes, measurement of SUN by dipstick can be used to identify, screen, and monitor pediatric patients with pAKI.