ETIOLOGY AND OUTCOMES OF PREGNANCY RELATED ACUTE KIDNEY INJURY-A TWO YEAR OBSERVATIONAL STUDY FROM A TERTIARY CARE CENTER IN MAHARASHTRA

A major contributor to maternal and fetal morbidity and mortality, especially in low- and middle-income nations, is pregnancy-related acute kidney injury (PRAKI).Although the incidence of PRAKI has decreased in developed countries due to advancements in obstetric care, but in developing countries persistent issues like insufficient prenatal care, delayed symptom recognition, and restricted access to specialized care continue to contribute to higher rates of reporting in settings with limited resources.

Preeclampsia ,PPH and sepsis are major causes in pregnancy that are the most common contributors to the multifactorial etiology of PRAKI.Even though  less common, other causes like acute fatty liver of pregnancy , Ahus, HELLP  syndrome are linked to serious morbidity.Both maternal renal recovery and fetal outcomes are strongly impacted by the timing of presentation and the standard of prenatal care.

Objective: To determine the incidence, etiological spectrum, and maternal-fetal outcomes of PRAKI in a tertiary care center over a two-year period.

Methods:  Study Design and Setting:-This was a cross-sectional observational study conducted in the Department of Nephrology at a tertiary care center from January 2023 to January 2025. The hospital caters to a large obstetric population and serves as a referral center for complicated pregnancies.

 Study Population :-All pregnant women presenting to our hospital during the study period were screened. Patients who developed AKI during pregnancy or within six weeks postpartum were classified as pregnancy-related AKI (PRAKI) cases and included in the study.

 Inclusion Criteria:-Pregnant women or postpartum patients (up to six weeks) diagnosed with AKI based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria.

 Exclusion Criteria-Patients with known chronic kidney disease (CKD) prior to pregnancy.

Patients with kidney transplantation.

Data Collection :-Demographic details, obstetric history (parity, gestational age), antenatal care status, clinical presentation, etiology of AKI, mode of delivery, and maternal and fetal outcomes were recorded. Etiology was determined based on clinical, laboratory, and imaging findings, along with obstetric assessment.

 Outcome Measures :-Maternal outcomes were categorized as complete recovery, dialysis dependence at discharge, or death. Fetal outcomes were classified as live birth or stillbirth/neonatal death.

Of 4105 AKI cases, 160 were PRAKI (3.9%). Among approximately 47,059 deliveries, the incidence of PRAKI was 0.34%.  The study included a total of 200 pregnant women with a mean age of 30.8 ± 8.0 years (range 18–44 years). The largest proportion of participants were in the 18–27 years age group (39%), followed by 28–37 years (33%) and 38–47 years (28%).

Table 1: Socio demographic Characteristics of Pregnant Women with Acute Kidney Injury

The study included a total of 200 pregnant women with a mean age of 30.8 ± 8.0 years (range 18–44 years). The largest proportion of participants were in the 18–27 years age group (44%), followed by 28–37 years (38%) and 38–47 years (18%). With respect to parity, a slightly higher proportion were multigravida (53.5%) compared to primigravida (46.5%). 

Table 2: Obstetric Profile

 Majority were in the 3rd  trimester (43%), followed by the 2nd trimester (32.5%) and the 1st trimester (24.5%).  . Regarding delivery outcomes, 31% had a normal vaginal delivery and 25.5% underwent cesarean section, whereas 22% had preterm or assisted deliveries and 21.5% were undelivered or had other outcomes at the time of assessment. More than half of the women (54%) had undergone at least one antenatal check-up.

Table 3: Clinical Profile and Etiology

History of hypertension disorder was present in 29% of pregnant women with acute kidney injury (AKI), while 71% had no such history. At presentation, 53.5% were hypertensive and 46.5% were normotensive. 

 Creatinine at Presentation (Mean ± SD): 3.45 ± 2.59 mg/dL

Need for Hemodialysis: 40 (25.0%)

On dialysis during discharge- 10(5%)

Plasma Exchange (PLEX): 16 (10.0%)

The major etiologies of PRAKI were:

 Preeclampsia/eclampsia - 36%

Postpartum hemorrhage – 31.5%

Sepsis – 27.5% 

Biopsy was done in patients having persistent AKI beyond 6 weeks.

In terms of maternal outcomes, 53.5% of pregnant women with acute kidney injury (AKI) died, while 46.5% survived. Regarding recovery status, only 50% achieved complete recovery indicating residual renal impairment. Fetal outcomes were similarly affected, with 48.5% of fetuses surviving and 51.5% experiencing adverse outcomes.

The association between creatinine levels and maternal and fetal outcomes was analyzed. Among patients with normal creatinine, 86% survived and 14% died, whereas among those with high creatinine ( more than 5mg/dl) 56.6% survived and 44.4% died; this difference was not statistically significant (χ² = 2.313, p = 0.128). For complete recovery, 86.2% of patients with normal creatinine recovered completely compared to 13.8% of those with high creatinine (χ² = 0.205, p = 0.651). Fetal recovery was significantly associated with maternal creatinine levels. In the normal creatinine group, 88.2% of the fetuses survived (0%), whereas in the high creatinine group, 49.7% of fetuses survived and 50.3% did not. This difference was statistically significant (χ² = 4.829, p = 0.028). Hypertension status was not significantly associated with creatinine levels, with 46.2% normotensive and 53.8% hypertensive among the high creatinine group (χ² = 0.376, p = 0.540).

 
Our results highlight the significance of enhancing multidisciplinary management including obstetrics, nephrology, and critical care teams, as well as enhancing antenatal surveillance and guaranteeing prompt referral to tertiary hospitals. PRAKI incidence and outcomes are anticipated to be most significantly impacted by public health initiatives that aim to lower the incidence of preeclampsia, hemorrhage, and sepsis.

Other causes were minimal.

PRAKI was responsible for 0.34% of pregnancies and 3.9% of all AKI cases. The main causes were sepsis, hemorrhage, and preeclampsia.

Our results highlight the significance of enhancing multidisciplinary management including obstetrics, nephrology, and critical care teams, as well as enhancing antenatal surveillance and guaranteeing prompt referral to tertiary hospitals. PRAKI incidence and outcomes are anticipated to be most significantly impacted by public health initiatives that aim to lower the incidence of preeclampsia, hemorrhage, and sepsis.

High maternal mortality and unfavorable fetal outcomes, despite good recovery rates, underscore the necessity of better prenatal care and early detection of high-risk pregnancies.