Incidence of acute kidney injury during pregnancy and its prognostic value for adverse clinical outcomes: A systematic review and meta-analysis

Acute Kidney Injury in Pregnancy: A Prospective Study

INTRODUCTION

When acute kidney damage occurs during pregnancy, it poses a difficult clinical problem. One of the main causes of maternal and fetal morbidity and death is pregnancy-related acute kidney injury (AKI), a significant obstetric complication characterized by a fast deterioration in renal function and several subsequent clinical problems. The objective of the study is to analyze the etiological factors, clinical manifestations, and maternal and fetal outcomes of AKI during pregnancy.

MATERIALS AND METHODS

This prospective observational research involved patients hospitalized in the General Medicine and Obstetrics and Gynecology departments at Indira Gandhi Institute of Medical Sciences, Patna, for a year (October 2021 to September 2022) due to obstetric difficulties resulting in acute renal damage.

RESULTS

The study included 62 patients with a mean age of 25.08±4.25 years. The majority of patients in our study were aged 18-25 years (38, 61.3%), followed by 26-30 years (19, 30.6%) and >30 years (5, 8.1%). The majority of patients in our study were non-booked (52, 83.9%) and presented as emergency cases, whereas 10 (16.1%) patients had booked. In addition, 34 (54.8%) patients were primigravida, while 28 (45.1%) were multigravida. There were 25 patients in their third trimester (40.3%), 19 who were postpartum (30.6%), 10 who were post-abortion (16.1%), and eight in their second trimester (12.9%). Upon admission, the majority of the patients showed signs of oliguria, accounting for 45 cases (72.6%). This was followed by nine cases of abnormal kidney function (14.5%) and eight cases of anuria (12.9%). Among the other symptoms, fever was observed in 25 cases (40.32%), whereas breathlessness increased to 15 cases (24.19%), edema was present in 14 cases (22.58%), vomiting and altered sensorium were observed in four cases (6.45%), abdominal pain was observed in three cases (4.83%), and burning micturition was observed in two cases (3.22%). The most common causes of AKI in pregnancy in the present study were puerperal sepsis (18 cases, 29.0%), followed by preeclampsia/eclampsia (14 cases, 22.6%), hemorrhagic shock (10 cases, 16.1%), septic abortion (six cases, 9.7%), hyperemesis gravidarum (four cases, 6.5%), acute fatty liver of pregnancy (three cases, 4.8%), disseminated intravascular coagulation (three cases, 4.8%), drug-induced sepsis (two cases, 3.2%), and urosepsis (two cases, 3.2%). Modes of delivery in this study were normal vaginal delivery (32 cases, 51.6%), lower segment cesarean section (21 cases, 33.9%), dilation and evacuation (seven cases, 11.3%), and total hysterectomy (two cases, 3.2%). Hemodialysis was performed in 39 patients (62.9%), and 51 (82.3%) received blood transfusions. The mean systolic and diastolic BP (mmHg) were 111.37±22.60 and 71.40±18.88, respectively. Maternal outcome data revealed that 48 (77.4%) women had fully recovered, eight (12.9%) had not recovered, 43 (69.4%) were lost to follow-up, and two (3.2%) had died. Neonatal outcomes in the present study were as follows: live birth, 43 (69.4%); abortion, eight (12.9%); intrauterine death of the fetus, five (8.1%); and neonatal mortality, six (9.7%).

CONCLUSION

The diagnosis and treatment of AKI during pregnancy is a significant challenge for the treating physician because of the pathophysiological changes that occur during pregnancy, the variability of symptoms, and the fact that clinical and laboratory features may occasionally overlap.

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.

Causes and outcome of pregnancy related acute kidney injury

Objective

To determine frequencies of causes and renal outcomes of pregnancy related acute kidney injury.

Method

This descriptive case series study was conducted in Nephrology unit of a tertiary care hospital of Peshawar, from 1st August 2021 to 31st July 2022.A total of 100 patients with acute kidney injury secondary to obstetric conditions were enrolled via non-probability consecutive sampling technique. While patients with pre-existing renal disease, those with renal stones, or having bilateral small kidneys on ultrasound were excluded from the study. Patients were followed till 12 weeks postpartum period. Underlying obstetrical causes and outcome at 12 weeks postnatal period were determined.

Results

The mean age of sample of 100 cases was 29.29 ± 6.45. Mean serum creatinine at presentation was 6.5± 3.13. Majority of patient, 89% were multigravidas. Seventy eight percent patients required hemodialysis. Primary postpartum hemorrhage remained the commonest underlying cause of pregnancy related acute kidney injury in this study. The frequency of persistent renal failure in Pr-AKI (pregnancy related acute kidney injury) in this study was 14%. In about 66% of cases complete recovery occurred. All the underlying obstetrical causes, when adjusted for age, gravidity, place and mode of delivery, had no association with persistent renal failure.

Conclusion

Primary postpartum hemorrhage is the predominant cause of pregnancy related acute kidney injury. By the end of 12 weeks postpartum, two third patients recover completely from pregnancy related acute renal injury.

The suppression of MAPK/NOX/MMP signaling prompts renoprotection conferred by prenatal naproxen in weaning preeclamptic rats

Although nonsteroidal antiinflammatory drugs (NSAIDs) are frequently used for fever and pain during pregnancy, their possible interaction with perinatal renal injury induced by preeclampsia (PE) has not been addressed. Here, studies were undertaken in the N(gamma)-nitro-L-arginine methyl ester (L-NAME) PE model to assess the influence of gestational NSAIDs on renal damage in weaning dams. PE-evoked increments and decrements in urine protein and creatinine clearance, respectively, were intensified by celecoxib and weakened by diclofenac or naproxen. Naproxen also improved renal cloudy swelling, necrosis, and reduced glomerular area evoked by PE. The concomitant rises in renal expression of markers of oxidative stress (NOX2/4), extracellular matrix metaloproteinase deposition (MMP9), and prostanoids (PGE2, PGF2α, TXA2) were all more effectively reduced by naproxen compared with celecoxib or diclofenac. Western blotting showed tripled expression of mitogen-activated protein kinases (MAPKs; p-p38, p-JNK1, p-ERK1, p-ERK2) in PE kidneys that was overturned by all NSAIDs, with naproxen producing the largest drop in p-ERK2 expression. The PE-provoked elevation in renal expression of autophagic marker LC3 was reduced by naproxen and diclofenac, but not celecoxib. The data suggests superior effect for naproxen over other NSAIDs in rectifying preeclamptic renal injury and predisposing inflammatory, oxidative, autophagic, and fibrotic signals.

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.

Indoxyl Sulfate Administration during Pregnancy Contributes to Renal Injury and Increased Blood-Brain Barrier Permeability

Rates of pregnancy-related acute kidney injury (PR-AKI) have increased in the U.S over the past two decades, but how PR-AKI affects the blood-brain barrier (BBB) is understudied. AKI is associated with increased amounts of uremic toxins, like indoxyl sulfate (I.S), whose chronic administration leads to BBB and cognitive changes. This study's objective was to determine if (1) PR-AKI increases I.S and (2) if administration of I.S during pregnancy elicits renal injury and/or increases BBB permeability. From gestational day (GD) 11 to GD19, Sprague Dawley rats were given either 100 or 200 mg/kg body-weight dose of I.S. PR-AKI was induced on GD18 via 45 min bilateral renal ischemic reperfusion surgery. On GD18, metabolic cage metrics and metabolic waste was collected and on GD19 blood pressure, and BBB permeability (by Evan's Blue infusion) were measured. I.S and creatinine were measured in both urine and circulation, respectively. One-way ANOVA or student t-tests were performed using GraphPad Prism with a p < 0.05 significance. I.S and PR-AKI led to oliguria. I.S administration led to increased BBB permeability compared to normal pregnant and PR-AKI animals. These results suggest that I.S administration during pregnancy leads to increased BBB permeability and evidence of renal injury comparable to PR-AKI animals.

Correlations between Maternal and Fetal Outcomes in Pregnant Women with Kidney Failure

BACKGROUND

Kidney function impairment in pregnancy is challenging, with incidence and prognosis only partially known. Studies concerning maternal and fetal outcomes in pregnancies occurring in patients with renal injury and the therapeutic strategies for improving the prognosis of these patients are scarce due to the limited number of cases reported.

OBJECTIVES

We aimed to establish correlations between the main maternal and fetal outcomes in patients with severe CKD or AKI in pregnancy to improve the prognosis, referring to a control group of patients with mild kidney impairment.

METHODS

For this purpose, we conducted a retrospective study, at University Emergency Hospital in Bucharest, Romania, from January 2019 until December 2021, selecting 38 patients with AKI and 12 patients diagnosed with advanced CKD, compared to 42 patients displaying borderline values of serum creatinine (0.8-1 mg/dL), reflecting the presence of milder kidney impairment.

RESULTS

The probability of having a child that is premature and small for gestational age, with a lower Apgar score and more frequent neonatal intensive care unit admissions, delivered by cesarean section, is higher in patients with highly reduced kidney function.

CONCLUSION

Severe kidney function impairment is associated with a grim fetal prognosis and obstetrical complications.