Pregnancy-related acute kidney injury in the African continent: where do we stand? A systematic review

Acute kidney injury in critically ill obstetric patients: Incidence and role of neutrophil gelatinase-associated lipocalcin - A prospective observational cohort study

Background and Aims

Data focussing on acute kidney injury (AKI) in obstetric patients admitted to the intensive care unit (ICU) are scarce and even more so regarding the role of neutrophil gelatinase-associated lipocalcin (NGAL) in detecting AKI or predicting outcomes in these patients. Hence, we aim to evaluate the incidence of AKI in obstetric ICU patients and validate the role of urinary and serum NGAL in predicting the onset of AKI and mortality.

Methods

This prospective observational cohort included 45 obstetric patients admitted in ICU, excluding those with prior renal dysfunction. Serum creatinine and urine output were monitored for the occurrence of AKI during the ICU stay. The outcome of the patient (survival or death) in the ICU and hospital was recorded, and serum and urinary NGAL were determined at the time of ICU admission.

Results

AKI occurred in 32 [71.1%; 95% confidence interval (CI): 55.4%, 86.8%] patients during their ICU stay. Serum NGAL showed an area under receiver operating characteristic curve (AUROCC) of 0.630 (95% CI: 0.417, 0.842) (P = 0.231) for AKI and 0.486 (95% CI: 0.295, 0.676) (P = 0.883) for ICU mortality. Urinary NGAL showed AUROC = 0.472 (95% CI: 0.285, 0.660) (P = 0.772) to predict AKI and 0.430 (95% CI: 0.268, 0.652) (P = 0.684) for ICU mortality.

Conclusions

AKI is common amongst critically ill obstetric ICU patients. However, serum and urinary NGAL cannot be advocated to discriminate between patients with or without AKI or between survivors and non-survivors in critically ill obstetric patients.

Risk factors and outcomes associated with pregnancy-related acute kidney injury in a high-risk cohort of women in Nigeria

INTRODUCTION

Despite a decline in developed countries, pregnancy-related acute kidney injury (PRAKI) remains a significant contributor to maternal mortality and adverse fetal outcomes in resource-constrained settings. Little is known about the impact of pregnancy-related acute kidney injury in Nigeria. Therefore, this study aimed to assess the incidence and maternal-fetal outcomes associated with pregnancy-related acute kidney injury among a cohort of high-risk women in Nigeria.

METHODS

This prospective multicenter study included women at high risk of acute kidney injury, who were more than 20 weeks pregnant or within 6 weeks postpartum and admitted to the Obstetrics and Gynecology units of two large public hospitals between September 1, 2019, and July 31, 2022. Acute kidney injury was defined and classified using the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

RESULTS

A total of 433 women, with mean age (± standard deviation) of 28 ± 6 years, were included in the evaluation. Pregnancy-related acute kidney injury occurred in 113 women (26.1%; 95% confidence interval [CI]: 21.1%-30.2%). The leading cause was preeclampsia (n = 57; 50.1%); 19 women died (4.4%), with 17 deaths (15%) occurring in the PRAKI group. Increasing severity of pregnancy-related acute kidney injury was independently associated with maternal mortality: adjusted odds ratio (aOR) for KDIGO stage 2 = 4.40; 95% CI 0.66-29.34, p = 0.13, and KDIGO stage 3 aOR = 6.12; 95% CI 1.09-34.34, p = 0.04. The overall perinatal mortality was 15% (n = 65), with 28 deaths (24.8%) occurring in the PRAKI group. Pregnancy-related acute kidney injury was also associated with an increased risk of perinatal mortality, aOR = 2.23; 95 CI 1.17-4.23, p = 0.02.

CONCLUSIONS

The incidence of pregnancy-related acute kidney injury was high, and significantly associated with maternal and perinatal mortality. The leading causes were hypertensive disorders of pregnancy.

Incidence of Pregnancy-Related Acute Kidney Injury in a Low Resource Setting: A Prospective Study

Background

Pregnancy-related acute kidney injury (PRAKI) is a common cause of AKI globally. The incidence and burden of PRAKI are still high in low and middle-income countries (LMICs) especially in Africa due to limited access to optimal obstetric care, late diagnosis, and referral. The study aimed to determine the incidence and aetiologies of PRAKI among women in the peripartum period in two government hospitals in Nigeria.

Methodology

This was a prospective study where serum creatinine was measured among pregnant women presenting in labour at 0-hour, 6 hour, 12 hour, 24 hour, 48 hour and 7 days post-delivery. AKI was defined using the Kidney Disease Improving Global Outcome criteria. Binary logistic regression was used to determine predictors of PRAKI.

Results

The mean age of the 162 pregnant women who completed the study was 30.05±1.28 years. The incidence of AKI use was 22.2%. The aetiologies of PRAKI were obstetric haemorrhage (66.7%), eclampsia (19.4%), and sepsis (13.9%). Seventeen (47.2%) patients had Stage 1 PRAKI, 12 (33.3%) had Stage 2 PRAKI, while seven (19.4%) had Stage 3 PRAKI. Factors significantly associated with PRAKI were parity (p=<0.001), caesarean section (p=<0.001), excess blood loss (p=<0.001), and prolonged duration of labour (p=0.002).

Conclusion

PRAKI occurred in 1 out 5 pregnant women in the peripartum period. Obstetric haemorrhage, sepsis, and eclampsia which are preventable or treatable are common major aetiologies of PRAKI. PRAKI is more associated with multi-parity, caesarean delivery, haemorrhage, and prolonged duration of labour. Optimal ante-natal care, health education, and prompt diagnosis and management of obstetric complications will reduce the incidence in Nigeria.