Pregnancy-Related Acute Kidney Injury in Preeclampsia: Risk Factors and Renal Outcomes

Development of normal reference intervals for renal function in pregnancy: a secondary analysis of clinical trial data

BACKGROUND

Due to its potential nephrotoxicity, screening for pre-existing renal function disorders has become a routine clinical assessment for initiating Tenofovir diphosphate fumarate (TDF)-containing antiretroviral treatment (ART) or pre-exposure prophylaxis (PrEP) in pregnant and non-pregnant adults. We aimed to establish reference values for commonly used markers of renal function in healthy pregnant women of African origin.

METHODS

Pregnant women ≥18 years, not living with HIV, and at 14-28 weeks gestation were enrolled in a PrEP clinical trial in Durban, South Africa between September 2017 and December 2019. Women were monitored 4-weekly during pregnancy until six months postpartum. We measured maternal weight and serum creatinine (sCr) at each visit and calculated creatinine clearance (CrCl) rates using the Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) formulae. Reference ranges for sCr and CrCl by CG and MDRD calculations were derived from the mean ± 2SD of values for pregnancy and postdelivery.

RESULTS

Between 14--and 40 weeks gestation, 249 African women not exposed to TDF-PrEP contributed a total of 1193 renal function values. Postdelivery, 207 of these women contributed to 800 renal function values. The normal reference range for sCr was 30-57 and 32-60 umol/l in the 2nd and 3rd trimesters of pregnancy. Normal reference ranges for CrCl using the MDRD calculation were 129-282 and 119-267 ml/min/1.73m2 for the 2nd and 3rd trimesters, respectively. Using the CG method of calculation, normal reference ranges for CrCl were 120-304 and 123-309 ml/min/1.73m2 for the 2nd and 3rd trimesters respectively. In comparison, the normal reference range for sCr, CrCl by MDRD and CG calculations postpartum was 40-77 umol/l, 92-201, and 90-238 ml/min/1.73m2, respectively.

CONCLUSIONS

In African women, the Upper Limit of Normal (ULN) for sCr in pregnancy is approximately 20% lower than 6 months postnatally. Inversely, the Lower Limit of Normal (LLN) for CrCl using either MDRD or CG equation is approximately 35% higher than 6 months postnatally. We provide normal reference ranges for sCr and CrCl for both methods of calculation and appropriate for the 2nd and 3rd trimesters of pregnancy in African women.

Machine learning, advanced data analysis, and a role in pregnancy care? How can we help improve preeclampsia outcomes?

The value of machine learning capacity in maternal health, and in particular prediction of preeclampsia will only be realised when there are high quality clinical data provided, representative populations included, different health systems and models of care compared, and a culture of rapid use and application of real-time data and outcomes. This review has been undertaken to provide an overview of the language, and early results of machine learning in a pregnancy and preeclampsia context. Clinicians of all backgrounds are encouraged to learn the language of Machine Learning (ML) and Artificial intelligence (AI) to better understand their potential and utility to improve outcomes for women and their families. This review will outline some definitions and features of ML that will benefit clinician's knowledge in the preeclampsia discipline, and also outline some of the future possibilities for preeclampsia-focussed clinicians via understanding AI. It will further explore the criticality of defining the risk, and outcome being determined.

Acute Kidney Injury in Pregnancies Complicated by Late-Onset Preeclampsia with Severe Features

OBJECTIVES

Acute kidney injury (AKI)-complicating pregnancy is used as a marker of severe maternal morbidity (SMM) and frequently associated with obstetric hypertensive disorders. We examined AKI in pregnancies complicated by late-onset preeclampsia with severe features (SPE) using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. We compared outcomes of pregnancies with and without AKI and stratified by stage of disease. We further differentiated renal dysfunction at the time of admission and compared outcomes to those who developed AKI after admission.

STUDY DESIGN

This was a retrospective cohort study of women with care established before 20 weeks and diagnosed with preeclampsia with severe features with delivery at ≥34 weeks. Women with chronic hypertension or suspected underlying renal dysfunction were excluded. KDIGO criteria were applied to stratify staging of renal disease. Demographics and perinatal outcomes were compared using Chi-square analysis and Wilcoxon's rank-sum test with p < 0.05 considered significant.

RESULTS

From January 2015 through December 2019, a total of 3,515 women meeting study criteria were delivered. Of these, 517 (15%) women met KDIGO criteria for AKI at delivery with 248 (48%) having AKI at the time of admission and the remaining 269 (52%) after admission. Stratified by severity, 412 (80%) had stage 1 disease, 89 (17%) had stage II, and 16 (3%) had stage III. Women with AKI had higher rates of cesarean delivery (risk ratio [RR] = 1.3; 95% confidence interval [CI]: 1.17-1.44), postpartum hemorrhage (RR = 1.46; 95% CI: 1.29-1.66), and longer lengths of stay. Other associated outcomes included NICU admission (RR = 1.72; 95% CI: 1.19-2.48), 5-minute Apgar score ≤ 3 (RR = 5.11; 95% CI: 1.98-13.18), and infant length of stay.

CONCLUSION

Of women with late preterm SPE, 15% were found to have AKI by KDIGO criteria. The majority (80%) of AKI was stage I disease, and approximately half of the cases were present by the time of admission.

KEY POINTS

· AKI was found in 15% of our cohort with 80% stage I disease.. · Half of the cases of AKI were present on admission.. · Few adverse perinatal outcomes are associated with AKI..

Pregnancy as a susceptible state for thrombotic microangiopathies

Pregnancy and the postpartum period represent phases of heightened vulnerability to thrombotic microangiopathies (TMAs), as evidenced by distinct patterns of pregnancy-specific TMAs (e.g., preeclampsia, HELLP syndrome), as well as a higher incidence of nonspecific TMAs, such as thrombotic thrombocytopenic purpura or hemolytic uremic syndrome, during pregnancy. Significant strides have been taken in understanding the underlying mechanisms of these disorders in the past 40 years. This progress has involved the identification of pivotal factors contributing to TMAs, such as the complement system, ADAMTS13, and the soluble VEGF receptor Flt1. Regardless of the specific causal factor (which is not generally unique in relation to the usual multifactorial origin of TMAs), the endothelial cell stands as a central player in the pathophysiology of TMAs. Pregnancy has a major impact on the physiology of the endothelium. Besides to the development of placenta and its vascular consequences, pregnancy modifies the characteristics of the women's microvascular endothelium and tends to render it more prone to thrombosis. This review aims to delineate the distinct features of pregnancy-related TMAs and explore the contributing mechanisms that lead to this increased susceptibility, particularly influenced by the "gravid endothelium." Furthermore, we will discuss the potential contribution of histopathological studies in facilitating the etiological diagnosis of pregnancy-related TMAs.

Urinary nephrin-a potential marker of early glomerular injury: a systematic review and meta-analysis

BACKGROUND

Both early recognition of glomerular injury and diagnosis of renal injury remain important problems in clinical settings, and current diagnostic biomarkers have limitations. The aim of this review was to determine the diagnostic accuracy of urinary nephrin for detecting early glomerular injury.

METHODS

A search was conducted through electronic databases for all relevant studies published until January 31, 2022. The methodological quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Pooled sensitivity, specificity, and other estimates of diagnostic accuracy were determined using a random effect model. The Summary Receiver Operating Characteristics (SROC) was used to pool the data and to estimate the area under the curve (AUC).

RESULTS

The meta-analysis included 15 studies involving 1587 participants. Overall, the pooled sensitivity of urinary nephrin for detecting glomerular injury was 0.86 (95% CI 0.83-0.89) and specificity was 0.73 (95% CI 0.70-0.76). The AUC-SROC to summarise the diagnostic accuracy was 0.90. As a predictor of preeclampsia, urinary nephrin showed a sensitivity of 0.78 (95% CI 0.71-0.84) and specificity of 0.79 (95% CI 0.75-0.82), and as a predictor of nephropathy the sensitivity was 0.90 (95% CI 0.87-0.93), and specificity was 0.62 (95% CI 0.56-0.67). A subgroup analysis using ELISA as a method of diagnosis showed a sensitivity of 0.89 (95% CI 0.86-0.92), and a specificity of 0.72 (95% CI 0.69-0.75).

CONCLUSION

Urinary nephrin may be a promising marker for the detection of early glomerular injury. ELISA assays appear to provide reasonable sensitivity and specificity. Once translated into clinical practice, urinary nephrin could provide an important addition to a panel of novel markers to help in the detection of acute and chronic renal injury.

Perioperative Complications in Patients with Preeclampsia Undergoing Caesarean Section Surgery

Caesarean section has risks of bleeding, infection and thromboembolism, and neuroendocrine-metabolic, and inflammatory-immune responses that may worsen outcomes in patients with preeclampsia. There is little research examining perioperative, as opposed to peripartum, outcomes in patients with preeclampsia. We conducted a single-centrecentre retrospective cohort study of perioperative patients with preeclampsia over an eight-month period to determine the rate of perioperative complication. Seventy-two patients were included. The maternal complication rate was 59.7 per 100 operations (95% CI 48.2 to 70.3%). Severe complications included pulmonary oedema 2 (2.8%), haemorrhage > 1000 mL 5 (6.9%), and blood transfusion 2 (2.8%). Twenty (27.8%) patients had a hospital length of stay ≥7 days. The rate of anaemia (haemoglobin < 110 g/L) on hospital discharge was 42 per 100 operations (95% CI 31.0 to 53.2%). Patient representation rate to hospital after discharge was 23.6% per 100 operations (95% CI 15.3 to 34.6%). There were no maternal deaths. The neonatal complication rate was 38.9 per 100 operations (95% CI 28.9 to 51.1%) with one foetal death. Patients with preeclampsia undergoing caesarean section are a very high-risk surgical group who experience significant perioperative complications. Urgent action is needed to confirm these findings and improve outcomes in these patients.

The Association between Advanced Maternal Age and the Manifestations of Preeclampsia with Severe Features

This retrospective cohort study aimed to explore the association between advanced maternal age and the clinical manifestations as well as laboratory parameters of preeclampsia with severe features. This study included 452 patients who were diagnosed with preeclampsia with severe features. The clinical and laboratorial characteristics of patients with preeclampsia with severe features aged ≥40 years old (study group) were compared to those of patients aged <40 years old (control group). Multivariant analysis was applied to assess the association between advanced maternal age and the manifestations of preeclampsia with severe features, adjusting for the variables that exhibited significant differences between the study and control groups. The multivariate analysis revealed that a maternal age of ≥40 years old was an independent risk factor for acute kidney injury (OR = 2.5, CI = 1.2-4.9, p = 0.011) and for new-onset postpartum preeclampsia (OR = 2.4, CI = 1.0-5.6, p = 0.046). Conversely, a maternal age ≥ 40 years old was associated with a reduced risk of HELLP syndrome (OR = 0.4, CI = 0.2-0.9, p = 0.018) and thrombocytopenia (OR = 0.5, CI = 0.3-0.9, p = 0.016) compared to that of the patients < 40 years of age. In conclusion, this study demonstrates that maternal age is significantly associated with the clinical manifestations and laboratory parameters of preeclampsia with severe features, highlighting the importance of age-specific management.

Postpartum resolution of hypertension, proteinuria and acute kidney injury among women with preeclampsia and severe features at Mulago National Referral Hospital, Uganda: a cohort study

Background

The resolution of hypertension, proteinuria and AKI postpartum among women with preeclampsia is not well documented in Uganda.

Objective

To determine the time to resolution of hypertension, proteinuria and AKI postpartum until 6 weeks among women with preeclampsia in Mulago Hospital, Uganda.

Methods

Between August 2017 and April 2018, we measured blood pressure, urine protein and serum creatinine on days 1,7,21 and 42 postpartum among 86 women with preeclampsia. The primary outcomes were time to the resolution of hypertension, proteinuria and AKI. We fitted accelerated failure models using Stata 17's stintreg. command with a log normal distribution and obtained time ratios of selected exposures on time to resolution of hypertension, proteinuria and AKI intervals.

Results

The median time to resolution of hypertension, proteinuria and AKI was seven (7) days (Inter quartile range, IQR 1-21). The time to resolution of hypertension among primiparous women was 3.5 times that of multiparous women [TR 3.5, 95%CI 1.1, 11.3]. No differences were observed in resolution of hypertension, proteinuria and acute kidney injury.

Conclusion

The time to resolution of hypertension, proteinuria and AKI was seven days. We recommend larger studies with longer follow-up beyond six-weeks postpartum to inform revision of our guidelines.

Hypertensive disorders of pregnancy

Hypertensive disorders of pregnancy (HDP) are one of the most commonly occurring complications of pregnancy and include chronic hypertension, gestational hypertension, and pre-eclampsia. New developments in early pregnancy screening to identify women at high risk for pre-eclampsia combined with targeted aspirin prophylaxis could greatly reduce the number of affected pregnancies. Furthermore, recent advances in the diagnosis of pre-eclampsia, such as placental growth factor based testing, have been shown to improve the identification of those pregnancies at highest risk of severe complications. Evidence from trials has refined the target blood pressure and timing of delivery to manage chronic hypertension and pre-eclampsia with non-severe features, respectively. Importantly, a wealth of epidemiological data now links HDP to future cardiovascular disease and diabetes decades after an affected pregnancy. This review discusses the current guidelines and research data on the prevention, diagnosis, management, and postnatal follow-up of HDP. It also discusses the gap in knowledge regarding the long term risks for cardiovascular disease following HDP and illustrates the importance of improving adherence to postnatal guidelines to monitor hypertension and the need for more research focused on primary prevention of future cardiovascular disease in women identified as being at high risk because of HDP.

Pre-eclampsia and Cardiovascular Disease: From Pregnancy to Postpartum

Hypertensive disorders of pregnancy (HDP) complicate approximately 10% of pregnancies. In addition to multiorgan manifestations related to endothelial dysfunction, HDP confers an increased risk of cardiovascular disease during delivery hospitalisation, such as heart failure, pulmonary oedema, acute MI and cerebrovascular events. However, the cardiovascular legacy of HDP extends beyond birth since these women are significantly more likely to develop cardiovascular risk factors in the immediate postnatal period and major cardiovascular disease in the long term. The main mediator of cardiovascular disease in women with a history of HDP is chronic hypertension, followed by obesity, hypercholesterolaemia and diabetes. Therefore, optimising blood pressure levels from the immediate postpartum period until the first months postnatally could have beneficial effects on the development of hypertension and improve long-term cardiovascular health. Peripartum screening based on maternal demographic, and clinical and echocardiographic data could help clinicians identify women with HDP at highest risk of developing postpartum hypertension who would benefit from targeted primary cardiovascular prevention.

The model of screening for preeclampsia in the second and third trimesters of gestation

<b>Purpose:</b> Preeclampsia (PE) is a specific syndrome of multiple organ insufficiency in case of pregnancy, which is included in the panel of major obstetric syndromes and is among the main causes of maternal morbidity and mortality in the whole world.<br /> <b>Material and methods</b>: We conducted a prospective cohort study of 91 pregnant women to evaluate the effectiveness of integrated use of maternal risk factors (2019 International Federation of Gynecology and Obstetrics recommendations), placenta location (ultrasound at 18-20 weeks of gestation), and serum cystatin C (at 18-36 weeks of gestation) in screening for pe in the second and third trimesters of gestation.<br /> <b>Results: </b>In the subgroup of pregnant women with cystatin C levels greater than 1.0 mg/L (27 women), PE developed in 26 women, which is 96.29% in percentage terms. When calculating GFR for cystatin C in a group with PE there was a significant violation of the renal filtration system -52.46±2.08 (95% CI, 48.39-56.54), while in healthy group the indicator is within normal limits -97.6±1.64 (95% CI, 94.38-100.82). In the analysis of the ratio of cystatin C levels more than 1.0 mg / l and the development of PE, a sensitivity of 98.46%, specificity of 100% and accuracy of 98.9%, p&lt;0.001.<br /> <b>Conclusions: </b>The data show that the combined model of maternal factors, ultrasound of the placenta and serum cystatin C, is prognostically effective in pregnant women in the second and third trimesters of gestation and is a reliable marker for the development of pe.

Evidence of kidney injury in preeclampsia: Increased maternal and urinary levels of NGAL and KIM-1 and their enhanced expression in proximal tubule epithelial cells

Background and objective

Proteinuria and glomerular endotheliosis are characteristics of glomerular injury in preeclampsia, a hypertensive disorder in human pregnancy. Neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) are biomarkers of acute/chronic renal tubule injury. To determine if tubule injury occurs in preeclampsia, we determined maternal plasma and urine NGAL and KIM-1 levels and evaluated NGAL and KIM-1 expression in kidney biopsy specimens from women with preeclampsia.

Methods

Prenatal and postpartum maternal blood and urinary samples were collected from three groups of pregnant women: normal pregnancy (n = 100), preeclampsia (n = 83), and pregnancy complicated with chronic hypertension (n = 20). Plasma and urine levels of NGAL and KIM-1 were measured by ELISA. Kidney biopsy tissue sections from patients with preeclampsia (n = 5) were obtained from Pathology Archives and processed to determine NGAL and KIM-1 expression by immunostaining and high kidney solution images were assessed by electron microscopy (EM).

Results

Prenatal plasma and urine levels of NGAL and KIM-1 were significantly higher in preeclamptic than in normal controls, p &lt; 0.01. In normal pregnancy, both plasma and urine levels of NGAL and KIM-1 at 24–48 h after delivery and 6–8 weeks postpartum were relatively comparable to that of antenatal levels. In preeclampsia, urine, but not plasma, NGAL levels were reduced at 6–8 weeks postpartum compared to the antenatal levels, p &lt; 0.05. Although maternal and urine KIM-1 levels were reduced at 6–8 weeks postpartum compared to the antenatal levels in preeclampsia, the levels were still higher than those in normal pregnancy. Positive expression of NGAL and KIM-1 was detected in proximal tubule epithelial cells in kidney tissue specimens from preeclampsia but not in non-pregnancy controls. EM examination showed glomerular and tubular injury in preeclampsia.

Conclusion

Our findings of increased maternal levels and urine secretion of NGAL and KIM-1, along with the upregulation of NGAL and KIM-1 expression in tubular epithelial cells in preeclampsia, provide plausible evidence that tubular injury exists in preeclampsia. The higher postpartum NGAL and KIM-1 levels in preeclamptic pregnancies indicate that tubular injury would not resolve within 2–3 months after delivery and suggest that proper follow-up and management of kidney function in women with preeclampsia would be necessary to reduce chronic kidney diseases in those women later in life.

Urine excretion of C3dg and sC5b-9 coincide with proteinuria and development of preeclampsia in pregnant women with type-1 diabetes

OBJECTIVE

Pregnant women with type-1 diabetes have an increased risk of preeclampsia with kidney injury and cardiovascular complications. Urine excretion of plasmin and soluble membrane attack complex (sC5b-9) is elevated in severe preeclampsia. We hypothesized a coupling between these events and that active plasmin promotes intratubular complement activation and membrane deposition.

METHODS

Stored urine and plasma samples from pregnant women with type-1 diabetes (n = 88) collected at gestational weeks 12, 20, 28, 32, 36 and 38 were used. In the cohort, 14 women developed preeclampsia and were compared with 16 nonpreeclampsia controls.

RESULTS

Urine C3dg and sC5b-9-associated C9 neoantigen/creatinine ratios increased and were significantly higher in women who developed preeclampsia. Plasma concentrations did not change with gestation. Urine plasmin(ogen) correlated to urine C3dg (r = 0.51, P < 0.001) and C9 neoantigen (r = 0.68, P < 0.001); urine albumin correlated to C3dg (r = 0.44, P < 0.001) and C9 (r = 0.59, P < 0.001). Membrane-associated C3dg and C9 neoantigen was detected in urinary extracellular vesicles from patients but not controls at 36 weeks. Receiver operating characteristic curves showed that C3dg and C9 neoantigen were inferior to albumin as predictive biomarkers for preeclampsia.

CONCLUSION

In preeclampsia, urinary excretion of activated complement relates significantly to albuminuria and to plasmin(ogen) but not to activation in plasma. Intratubular complement activation in preeclampsia is a postfiltration event tightly related to proteinuria/plasminogenuria and a possible mechanistic link to cellular damage and kidney injury.

Preeclampsia and the Kidney: Pathophysiology and Clinical Implications

Preeclampsia and other hypertensive disorders of pregnancy are major contributors to maternal morbidity and mortality worldwide. This group of disorders includes chronic hypertension, gestational hypertension, preeclampsia, preeclampsia superimposed on chronic hypertension, and eclampsia. The body undergoes important physiological changes during pregnancy to allow for normal placental and fetal development. Several mechanisms have been proposed that may lead to preeclampsia, including abnormal placentation and placental hypoxia, impaired angiogenesis, excessive pro-inflammatory response, immune system imbalance, abnormalities of cellular senescence, alterations in regulation and activity of angiotensin II, and oxidative stress, ultimately resulting in upregulation of multiple mediators of endothelial cell dysfunction leading to maternal disease. The clinical implications of preeclampsia are significant as there are important short-term and long-term health consequences for those affected. Preeclampsia leads to increased risk of preterm delivery and increased morbidity and mortality of both the developing fetus and mother. Preeclampsia also commonly leads to acute kidney injury, and women who experience preeclampsia or another hypertensive disorder of pregnancy are at increased lifetime risk of chronic kidney disease and cardiovascular disease. An understanding of normal pregnancy physiology and the pathophysiology of preeclampsia is essential to develop novel treatment approaches and manage patients with preeclampsia and hypertensive disorders of pregnancy. © 2023 American Physiological Society. Compr Physiol 13:4231-4267, 2023.

Persistent hypertension at 3 months postpartum among women with hypertensive disorders of pregnancy at a tertiary hospital in Southwestern Uganda

BACKGROUND

Hypertension is a key contributor to the global epidemic of cardiovascular disease and is responsible for more deaths worldwide than any other cardiovascular risk factor. Hypertensive disorders of pregnancy, of which preeclampsia and eclampsia are the most common forms, have been shown to be a female-specific risk factor for chronic hypertension.

OBJECTIVE

This study aimed to determine the proportion and risk factors for persistent hypertension at 3 months after delivery among women with hypertensive disorders of pregnancy in Southwestern Uganda.

STUDY DESIGN

This was a prospective cohort study of pregnant women with hypertensive disorders of pregnancy admitted for delivery at Mbarara Regional Referral Hospital in Southwestern Uganda from January 2019 to December 2019; however, women with chronic hypertension were excluded from the study. The participants were followed up for 3 months after delivery. Participants with a systolic blood pressure of ≥140 mm Hg or a diastolic blood pressure of ≥90 mm Hg or receiving antihypertension therapy at 3 months after delivery were considered to have persistent hypertension. Multivariable logistic regression was used to determine independent risk factors associated with persistent hypertension.

RESULTS

A total of 111 participants with hypertensive disorders of pregnancy diagnosed at hospital admission were enrolled with a follow-up rate of 49% (54/111) at 3 months after delivery. Of these women, 21 of 54 (39%) had persistent hypertension 3 months after delivery. In the adjusted analyses, an elevated serum creatinine level (>106.08 µmol/L [≤1.2 mg/dL]) at admission for delivery was the only independent risk factor for persistent hypertension at 3 months after delivery (adjusted relative risk, 1.93; 95% confidence interval, 1.08-3.46; P=.03), controlling for age, gravidity, and eclampsia.

CONCLUSION

Approximately 4 of 10 women presenting with hypertensive disorders of pregnancy at our institution remained hypertensive 3 months after delivery. Innovative strategies are needed to identify these women and provide long-term care to optimize blood pressure control and reduce future cardiovascular disease after hypertensive disorders of pregnancy.

Predictors of Preeclampsia in the First Trimester in Normotensive and Chronic Hypertensive Pregnant Women

Preeclampsia (PE) is characterized by the new onset of hypertension (HT) and proteinuria beyond the 20th week of gestation. We aimed to find the best predictor of PE and find out if it is different in women with or without HT. Consecutively attended pregnant women were recruited in the first trimester of pregnancy and followed-up. Laboratory and office and 24 h-ambulatory blood pressure (BP) data were collected. PE occurred in 6.25% of normotensives (n = 124). Both office mean BP and 24 h-systolic BP in the first trimester were higher in women with versus those without PE (p ≤ 0.001). In women with chronic hypertension (cHT), PE occurred in 55%; office SBP (p = 0.769) and 24 h-SBP (p = 0.589) were similar between those with and those without PE. Regarding biochemistry, in cHT, plasma urea and creatinine were higher in PE women than in those without cHT (p = 0.001 and p = 0.004 for the differences in both parameters). These differences were not observed in normotensives. In normotensives, mean BP was the best predictor of PE [ROC curve = 0.91 (95%CI 0.82-0.99)], best cut-off = 80.3 mmHg. In cHT, plasma urea and creatinine were the best predictors of PE, with ROC curves of 0.94 (95%CI 0.84-1.00) and 0.93 (95%CI 0.83-1.00), respectively. In the first trimester of pregnancy, the strongest predictor of PE in normotensive women is office mean BP, while in cHT, renal parameters are the strongest predictors. Otherwise, office BP is non-inferior to 24 h ambulatory BP to predict PE.

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

BACKGROUND

Pregnancy-Related Acute kidney injury (PR-AKI) is a global health problem with substantial maternal and fetal morbidity and mortality. However, little is known about the current situation in the developing world including African countries. Africa is the poorest continent per capita, and women from Sub-Saharan Africa alone account for 66% of the estimated global maternal deaths from preventable obstetric causes.

METHODS

OBJECTIVE: To review the literature on the clinical profile, maternal and renal outcomes of women with PR-AKI in the African continent.

SEARCH STRATEGY

Medline, ISI Web of Science, Scopus, and Cochrane library were searched in February 2022, using the MeSH terms and text key words: "pregnancy", "pregnant", "acute kidney injury", "acute renal insufficiency", "acute renal injury", "acute renal failure", and "Africa".

SELECTION CRITERIA AND DATA COLLECTION

Studies from African countries which reported maternal and renal outcomes in women with PR-AKI during pregnancy or postpartum were included. Editorials, short communications, and case reports were excluded. The study quality was assessed using the NHLBI tool. Data extraction was done using predefined data fields.

RESULTS

A total of 167 studies were evaluated, of which 14 studies from seven African countries met the inclusion criteria. Preeclampsia, obstetric hemorrhage, and sepsis represented the main causes of PR-AKI. Maternal mortality ranged between 0 and 34.4%. Although the majority of women needed ICU admission and hemodialysis, renal recovery occurred in 53.1-90% of patients. Perinatal mortality has been reported to be 1.5-60.5% in the included studies.

AUTHORS' CONCLUSIONS

PR-AKI in Africa represents the second leading cause of AKI. Limited access to obstetric care, late referral, and late diagnosis of women with risks for PR-AKI hinder the curtailment of the problem. Provision of health care facilities with adequately trained personnel and implementation of preventive strategies will be of great value in decreasing the magnitude of the problem.

Pregnancy-Associated Acute Kidney Injury in Low-Resource Settings: Progress Over the Last Decade

Despite immense global effort, the maternal mortality rate in low-resource settings remains unacceptably high. Globally, this reflects the grave inequalities in access to health and reproductive services. Pregnancy-associated acute kidney injury (PRAKI) is an independent risk factor for mortality. The reported incidence of PRAKI in low- and middle-income countries is higher than that of high-income countries (4%-26% versus 1%-2.8%, respectively). Hypertensive disorders are now the leading cause of PRAKI in many regions, followed by hemorrhage and sepsis. PRAKI in low-resource settings carries a high mortality for both mother and child. Outcome studies suggest that PRAKI is associated with residual kidney dysfunction and may lead to dialysis dependence. This can be a death sentence in many regions with limited kidney replacement therapy. This review will summarize data on PRAKI on the African, Latin American, and Asian continents over the past decade. It will include the progress in published data, mortality, and treatment interventions and provide recommendations for the next decade.

Trends and outcomes for deliveries with hypertensive disorders of pregnancy from 2000 to 2018: A repeated cross-sectional study

OBJECTIVE

To analyse trends, risk factors, and outcomes related to hypertensive disorders of pregnancy (HDP).

DESIGN

Repeated cross-sectional.

SETTING

US delivery hospitalisations.

POPULATION

Delivery hospitalisations in the 2000-2018 National Inpatient Sample.

METHODS

US hospital delivery hospitalisations with HDP were analysed. Several trends were analysed: (i) the proportion of deliveries by year with HDP, (ii) the proportion of deliveries with HDP risk factors and (iii) adverse outcomes associated with HDP including maternal stroke, acute renal failure and acute liver injury. Risk ratios were determined using regression models with HDP as the exposure of interest.

MAIN OUTCOME MEASURES

Prevalence of HDP, risk factors for HDP and associated adverse outcomes.

RESULTS

Of 73.1 million delivery hospitalisations, 7.7% had an associated diagnosis of HDP. Over the study period, HDP doubled from 6.0% of deliveries in 2000 to 12.0% in 2018. The proportion of deliveries with risk factors for HDP increased from 9.6% in 2000 to 24.6% in 2018. In adjusted models, HDP were associated with increased stroke (aRR [adjusted risk ratio] 15.9, 95% CI 14.8-17.1), acute renal failure (aRR 13.8, 95% CI 13.5-14.2) and acute liver injury (aRR 1.2, 95% CI 1.2-1.3). Among deliveries with HDP, acute renal failure and acute liver injury increased; in comparison, stroke decreased.

CONCLUSION

Hypertensive disorders of pregnancy increased in the setting of risk factors for HDP becoming more common, whereas stroke decreased.

TWEETABLE ABSTRACT

While hypertensive disorders of pregnancy increased from 2000 to 2018, stroke appears to be decreasing.

Clinical practice guideline for the prevention and management of hypertensive disorders of pregnancy

Objectives: To provide clinical recommendations based on evidence for the the prevention and management of HDP in EsSalud. Methods: A CPG for the the prevention and management of HDP in EsSalud was developed. To this end, a guideline development group (local GDG) was established, including medical specialists and methodologists. The local GDG formulated 8 clinical questions to be answered by this CPG. Systematic searches of systematic reviews and—when it was considered pertinent—primary studies were searched in PubMed y Central during 2021. The evidence to answer each of the posed clinical questions was selected. The quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. In periodic work meetings, the local GDG used the GRADE methodology to review the evidence and formulate the recommendations, the points of good clinical practice and flowcharts for the prevention, management and follow-up. Finally, the CPG was approved with Resolution 112-IETSI-ESSALUD-2021. Results: This CPG addressed 8 clinical questions, divided into three topics: prevention, management and follow-up of the HDP. Based on these questions, 11 recommendations (6 strong recommendations and 5 weak recommendations), 32 points of good clinical practice, and 3 flowcharts were formulated. Conclusions: The main recommendations in the guideline are the use of magnesium sulfate for the treatment of severe pre-eclampsia and eclampsia. The guideline must be updated in three years’ time.

Acute Kidney Injury in Severe Preeclamptic Patients Admitted to Intensive Care Unit: Epidemiology and Role of Serum Neutrophil Gelatinase-associated Lipocalcin

Background

Patients with preeclampsia admitted to the intensive care unit (ICU) may have risk factors for acute kidney injury (AKI). Although the use of neutrophil gelatinase-associated lipocalcin (NGAL) to predict AKI is previously validated, we could locate only scanty data regarding the epidemiology of AKI and role of NGAL in preeclamptic patients admitted to ICU.

Methods

Patients with preeclampsia admitted to our ICU were included. The incidence and severity of AKI during the entire ICU stay were assessed using kidney disease improving global outcomes criteria, while the a priori risk factors and serum NGAL were also evaluated.

Results

A total of 52 preeclamptic patients admitted to ICU were included, among whom the majority had eclampsia (75%). AKI developed in 25 (48.1%) patients with stages 1, 2, and 3 in 56, 36, and 8%, respectively. The incidence of sepsis (16 vs 0%), shock (40 vs 7.4%), and anemia (84 vs 59.3%) was significantly greater in patients with AKI (p < 0.05). ICU mortality (28 vs 3.7%), duration of ICU, and hospital stay were significantly higher in patients who developed AKI (p < 0.05). There was no association of serum NGAL [274 (240–335) ng/mL] with AKI or the mortality (p = 0.725, 0.861); there was, however, a significant discriminatory value for eclampsia [p = 0.019; area under curve = 0.736 (95% confidence interval: 0.569–0.904)].

Conclusions

Although AKI is common among patients with preeclampsia admitted to ICU, serum NGAL does not predict its occurrence.

How to cite this article

Tyagi A, Yadav P, Salhotra R, Das S, Singh PK, Garg D. Acute Kidney Injury in Severe Preeclamptic Patients Admitted to Intensive Care Unit: Epidemiology and Role of Serum Neutrophil Gelatinase-associated Lipocalcin. Indian J Crit Care Med 2021;25(9):1013–1019.

Severe thrombocytopenia and microangiopathic hemolytic anemia in pregnancy: A guide for the consulting hematologist

A hematologist receives a call from a maternal-fetal medicine (MFM) physician about a previously healthy patient who became ill at 25 weeks' gestation. Her mental status is deteriorating. There are signs of fetal distress. Platelet count and hemoglobin are falling. The MFM physician is considering the hemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome. For the hematologist, everything seems unfamiliar. Our goal is to provide hematologists with the fundamental knowledge required for understanding and managing these patients who become suddenly and seriously ill during pregnancy and in whom thrombocytopenia and microangiopathic hemolytic anemia are part of their presentation.

NGAL for Preeclampsia: How Sure are We?

How to cite this article: Gupta S, Tomar DS. NGAL for Preeclampsia: How Sure are We? Indian J Crit Care Med 2021;25(9):972-973.

Sonographic Assessment of Renal Volume in Normotensive Pregnant Women and Women With Pregnancy-Induced Hypertension in Enugu Metropolis

Objective:

Renal volume (RV) assessment during obstetric sonography is rarely considered in our locality. Understanding the changes in RV in both normotensive pregnant (NP) and pregnancy-induced hypertensive (PIH) women is important in making correct diagnosis regarding pregnancy outcome. This study is aimed at determining the RV in NP and PIH women and correlating RV with fetal gestational age (FGA), body mass index (BMI), and parity in NP women.

Materials and Methods:

This cross-sectional study involved 450 patients recruited at a Tertiary Hospital. A pilot study was done to determine the interobserver variability in RV measurement. RV was calculated using the following formula: L × W × AP × 0.523. Parity, BMI, and blood pressure were documented, while FGA was calculated as an average of FGAs obtained from the measurements of fetal biometric parameters.

Results:

Mean RV of PIH women was significantly higher than that of NP women ( P < .05). RV shows a positive significant relationship with BMI and FGA, while it shows a negative relationship with parity in NP ( P < .05).

Conclusion:

Reference range values of RV were generated for clinical use in our locality, while there is statistically significant difference between RV in NP and PIH women.

Pregnancy-related acute kidney injury at high altitude: a retrospective observational study in a single center

Background

Pregnancy-related acute kidney injury (Pr-AKI) is associated with maternal and fetal morbidity and mortality. There are few studies focusing on Pr-AKI at high altitude in the literature.

Objectives

to investigate the incidence, etiology, clinical features and maternal-fetal outcomes of Pr-AKI in women living at high altitude.

Methods

6,512 pregnant women attending the Department of Obstetrics & Gynecology at local hospital from January 2015 to December 2018 were screened for Pr-AKI. Patients with serum creatinine above normal range(> 70umol/L) then underwent assessment to confirm the diagnosis of Pr-AKI. AKI was diagnosed and staged based on Kidney Disease Improving Global Outcomes(KDIGO) guideline. Individuals meeting the Pr-AKI criteria were recruited. Their clinical data were recorded and retrospectively analyzed.

Results

Pr-AKI was identified in 136/6512(2.09 %) patients. Hypertensive disorders of pregnancy(HDP) was the leading cause of Pr-AKI(35.3 %). 4(2.9 %) women died and the majority(86.1 %) had recovered renal function before discharge. Fetal outcomes were confirmed in 109 deliveries with gestational age ≥ 20 weeks. Pre-term delivery occurred in 30(27.3 %) cases and perinatal deaths in 17(15.5 %). The rate of low birth weight infant(LBWI) and intrauterine growth restriction(IUGR) was 22.0 and 10.9 % respectively. 16(14.5 %) infants were admitted to NICU after birth. Patients with HDP had a higher cesarean rate(56.3 %). More IUGR(25.0 %) and LBWI(37.8 %) were observed in their infants with a higher risk of admission to NICU(22.0 %). High altitude might have an adverse impact on HDP-related Pr-AKI patients with earlier terminated pregnancy and more stillbirth/neonatal death. Logistic regression models indicated that uncontrolled blood pressure, high altitude and advanced AKI were associated with adverse fetal outcomes in HDP-related Pr-AKI patients.

Conclusions

Pr-AKI was not rare in high-altitude regions and caused severe fetal morbidities and mortalities. Uncontrolled blood pressure, high altitude and advanced AKI were all risk factors for adverse fetal outcomes in Pr-AKI patients, especially for those with hypertensive disorders of pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02418-7.

The (pro)renin receptor ((P)RR) and soluble (pro)renin receptor (s(P)RR) in pregnancy

The (pro)renin receptor ((P)RR) is a multi-functional protein that can be proteolytically cleaved and released in a soluble form (s(P)RR). Recently, the (P)RR and s(P)RR have become of interest in pregnancy and its associated pathologies. This is because the (P)RR not only activates tissue renin angiotensin systems, but it is also an integral component of vacuolar-ATPase, activates the wingless/integrated (Wnt)/β-catenin and extracellular signal regulated kinases 1 and 2/mitogen-activated protein kinase signalling pathways, and stabilises the β subunit of pyruvate dehydrogenase. Additionally, s(P)RR is detected in plasma and urine, and maternal plasma levels are elevated in pregnancy complications including fetal growth restriction, preeclampsia and gestational diabetes mellitus. Therefore, s(P)RR has potential as a biomarker for these pregnancy pathologies. Preliminary functional findings suggest that s(P)RR may be important for regulating fluid balance, inflammation and blood pressure, all of which contribute to a successful pregnancy. The (P)RR and s(P)RR regulate pathways that are known to be important in maintaining pregnancy, however their role in the physiological context of pregnancy is poorly characterised. This review summarises the known and potential functions of the (P)RR and s(P)RR in pregnancy, and how their dysregulation may contribute to pregnancy complications. It also highlights the need for further research into the source and function of s(P)RR in pregnancy. Soluble (P)RR levels could be indicative of placental, kidney or liver dysfunction and therefore be a novel clinical biomarker, or therapeutic target, to improve the detection and treatment of pregnancy pathologies.

Factors associated with acute kidney injury during delivery or the postpartum period: A case control study

INTRODUCTION

To investigate the incidence of risk factors associated with acute kidney injury(AKI) occurring during the intrapartum or the immediate postpartum period.

MATERIAL AND METHODS

A retrospective case control study in a tertiary UK hospital of pregnant women identified with AKI in labour or in the postpartum period between July 2019 and June 2020 was carried out. Women identified with pregnancy related AKI (pr-AKI) in labour or postpartum were compared with a matched cohort of women with no evidence of pr-AKI, using multiple regression analysis.

RESULTS

In 4600 births, 71 women with pr-AKI and 142 control women were identified. The antenatal and intrapartum risk factors strongly associated with pr-AKI were pre-eclampsia, prolonged ruptured membranes, delivery by emergency caesarean section and greater blood loss at delivery (all p < 0.001 in multivariable regression).

CONCLUSION

Pr-AKI is relatively common, occurring in 1.5 % of our cohort. Women who are overweight, have prolonged rupture of the membranes, an emergency caesarean section and/or a postpartum haemorrhage are at greatest risk. Clinicians should be check renal function before prescribing non-steroidal medication for postpartum pain relief if there are risk factors for AKI.

Predictive value of vitamin A and E levels in pre-eclampsia and postpartum kidney injury

OBJECTIVE

This research aimed to explore the predictive value of levels of vitamin A and E in pre-eclampsia and postpartum kidney injury.

METHODS

A total of 106 pregnant women with severe pre-eclampsia diagnosed in our hospital from May 2015 to December 2018 were selected as the research subjects. There from, 75 pregnant women with severe pre-eclampsia were enrolled into the severe PE group (SPE) and 31 with acute kidney injury were divided into the severe PE and AKI group (SPE and AKI). Serum vitamin A and E content was determined by high-performance liquid chromatography (HPLC), and the correlation between vitamins A and E and disease was analyzed. The expression levels of kidney injury markers in both groups were detected, and the correlation between markers and vitamin A and E levels was analyzed.

RESULTS

The expression level of vitamins A and E decreased in the pre-eclampsia and postpartum kidney injury, and it was negatively correlated with disease severity. The expression of the two decreased further in the severe pre-eclampsia patients with kidney injury. In addition, the expression of kidney injury markers in the severe pre-eclampsia patients with postpartum kidney injury was higher than that in severe pre-eclampsia patients, and it was negatively correlated with vitamin A and E levels.

CONCLUSION

Vitamins A and E are expressed in low levels in pre-eclampsia and postpartum kidney injury, and the latter has a higher sensitivity and specificity than the former. It is negatively correlated with kidney injury markers KIM-1, NGAL, UA and Scr, which can be used as a physical and chemical indexes for clinical prediction.

Hydrogen sulfide releasing molecule MZe786 inhibits soluble Flt-1 and prevents preeclampsia in a refined RUPP mouse model

An imbalance in angiogenic growth factors and poor utero-placental perfusion are strongly associated with preeclampsia. The reduced utero-placental perfusion (RUPP) model that mimics insufficient placental perfusion is used to study preeclampsia. The aim of this study was to develop a refined RUPP model in C57Bl/6 J mice to test the efficacy of MZe786 as a potential inhibitor of soluble Flt-1 for preeclampsia therapy. Murine RUPP (mRUPP) was induced through bilateral ligation of the ovarian arteries at E11.5 that resulted in typical preeclampsia symptoms including increase in mean arterial pressure (MAP), kidney injury and elevated soluble Flt-1 (sFlt-1) levels in the maternal plasma and amniotic fluid. The murine RUPP kidneys showed tubular and glomerular damage along with increased oxidative stress characterised by increased nitrotyrosine staining. The mRUPP displayed abnormal placental vascular histology, reduced expression of placental cystathionine γ-lyase (CSE), the hydrogen sulfide (H₂S) producing enzyme, and resulted in adverse fetal outcomes (FGR). Importantly, oral administration of hydrogen sulfide (H₂S)-releasing compound MZe786 from E11.5 to E17.5 successfully prevented the development of preeclampsia. Specifically, MZe786 treatment reduced maternal MAP and kidney nitrotyrosine staining and improved fetal outcome. The circulation levels of sFlt-1 were dramatically decreased in MZe786 treated animals implying that H₂S released from MZe786 offered protection by inhibiting sFlt-1 levels. MZe786 prevent preeclampsia and warrant a rapid move to randomised control clinical trial.

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Refined mouse reduced uterine perfusion pressure (mRUPP) model exhibits preeclampsia symptoms.

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Mouse RUPP induces maternal hypertension, kidney injury, elevates circulating sFlt-1 levels and promotes nitrosative stress.

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Mouse RUPP reduces expression of the protective enzyme, placental cystathionine γ-lyase and causes poor fetal outcome.

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H₂S releasing aspirin, MZe786, acts as an inhibitor of sFlt-1 to successfully prevent preeclampsia and improve fetal outcome.

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MZe786 is a novel drug with therapeutic potential to prevent preeclampsia.

Acute Kidney Injury in Pregnancy

Acute kidney injury in pregnancy is a public health problem and a significant cause of maternal and fetal morbidity and mortality. The incidence of pregnancy-related acute kidney injury has increased in the developed countries, theorized to be the result of an increase in pregnancies in advanced maternal age, and continues to remain higher in developing countries owing to inadequate antenatal care. While hyperemesis gravidarum is a common cause of pregnancy-related acute kidney injury during the first trimester, complications such as preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, acute fatty liver disease of pregnancy, thrombotic thrombocytopenic purpura, and hemolytic uremic syndrome are important causes of acute kidney injury later in the pregnancy. Diagnosis of pregnancy-related acute kidney injury can be difficult owing to lack of diagnostic criteria and overlapping clinical features between various causes. General measures to treat pregnancy-related acute kidney injury include identification of the underlying cause of kidney injury, intravenous fluid resuscitation, timely initiation of dialysis if needed, and prompt fetal delivery, if necessary. Specific treatment includes steroid and immunosuppressive therapy for glomerulonephritis; prompt delivery for severe preeclampsia, hemolysis, elevated liver enzymes, and low platelet count syndrome, and acute fatty liver of pregnancy; and plasmapheresis and eculizumab for thrombotic microangiopathies such as thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome.

Acute kidney injury during pregnancy leads to increased sFlt-1 and sEng and decreased renal T regulatory cells in pregnant rats with HELLP syndrome

BACKGROUND

The incidence of acute kidney injury (AKI) during pregnancy precedes a high maternal mortality rate of 20-40%. AKI during pregnancy has multiple etiologies; however, the more common are maternal hypertensive disorders, which include preeclampsia and HELLP (hemolysis, elevated liver enzyme, low platelet) syndrome. Therefore, we sought to assess the impact of AKI on blood pressure, kidney injury, and anti-angiogenic factors during pregnancies with and without HELLP syndrome.

METHODS

On gestational day (GD) 12, mini-osmotic pumps were inserted into a subset of normal pregnant (NP) rats infusing 4.7 μg/kg soluble fms-like tyrosine kinase-1 (sFlt-1) and 7 μg/kg soluble endoglin (sEng) to induce HELLP syndrome. On GD18, the renal pedicles were occluded for 45 min to induce AKI via bilateral ischemia reperfusion in a subset of NP (n = 18) or HELLP (n = 20) rats. Control NP (n = 20) and HELLP (n = 20) rats underwent a SHAM surgery on GD18. Plasma, urine, and maternal organs were saved for further analysis. Renal injury was assessed via renal histopathology, glomerular filtration rate (GFR), T cell infiltration, and assessment of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL). Data was measured via two-way analysis of variance with Tukey's test for post hoc analysis.

RESULTS

Blood pressures were increased in HELLP+AKI rats (p = 0.0001); both NP+AKI and HELLP+AKI rats had increased lactate dehydrogenase (p < 0.0001) and aspartate aminotransferase levels (p < 0.0001), and decreased platelet levels (p < 0.001) vs. NP rats. HELLP+AKI (p = 0.002) and HELLP rats (p = 0.0002) had evidence of renal fibrosis vs. NP rats. GFR was decreased in HELLP+AKI (p = 0.01) rats vs. NP rats. Urinary KIM-1 was increased in NP+AKI rats vs. NP (p = 0.003) and HELLP rats (p = 0.01). HELLP+AKI rats had increased urinary KIM-1 vs. NP (p = 0.0008) and HELLP rats (p = 0.004) and increased NGAL vs. HELLP rats (p = 0.002). HELLP+AKI rats had increased sFlt-1 (p = 0.009) vs. NP rats. NP+AKI (p = 0.02) and HELLP+AKI (p = 0.007) rats had increased sEng vs. NP rats. CD3+CD4+ T cells were significantly increased in HELLP+AKI rats vs. NP (p = 0.0002) and NP+AKI (p = 0.05) rats. T regulatory cells were significantly decreased in HELLP+AKI (p = 0.03) and NP+AKI (p = 0.02) rats vs. NP rats; there were no changes between groups in T helper 17 cells (p = 0.34).

CONCLUSION

The findings in this study suggest that AKI during pregnancy contributes to increased blood pressure and biochemical markers for HELLP syndrome, creates an anti-angiogenic imbalance, and exacerbates kidney injury as shown on histopathology, GFR, and kidney injury markers.

CKD and Pregnancy Outcomes in Africa: A Narrative Review

Chronic kidney disease (CKD) is associated with adverse maternal and fetal outcomes and is reported to affect up to 3% of women of reproductive age in high-income countries, but estimated prevalence may be as much as 50% higher in low and middle-income countries (LMICs). All pregnancy complications occur much more frequently in women in LMICs compared with those in high-income countries. Given the anticipated high prevalence of CKD in women of reproductive age and high rates of maternal and fetal adverse events in Africa, we sought to explore the association between CKD and pregnancy outcomes in this setting through a narrative review of the literature. This review demonstrates the paucity of data in this area and highlights the systemic barriers that exist in many African countries that prevent robust management of noncommunicable diseases such as CKD during a woman's reproductive life. This evidence gap highlights the need for further research, starting by sampling normal ranges of serum creatinine concentrations in pregnant and nonpregnant women of reproductive age in the diverse populations of Africa, estimating prevalence of CKD, and understanding associated pregnancy outcomes. Research should then focus on pragmatic interventions that may improve outcomes for women and their infants.

Racial and Ethnic Disparities in Pregnancy-Related Acute Kidney Injury

BACKGROUND

Pregnancy-related AKI (PR-AKI) is increasing in the United States. PR-AKI is associated with adverse maternal outcomes. Disparities in racial/ethnic differences in PR-AKI by race have not been studied.

METHODS

This was a retrospective cohort study using the National Inpatient Sample (NIS) from 2005 to 2015. We identified patients who were admitted for a pregnancy-related diagnosis using the Neomat variable provided by the NIS database that indicates the presence of a maternal or neonatal diagnosis code or procedure code. PR-AKI was identified using ICD codes. Survey logistic regression was used for multivariable analysis adjusting for age, medical comorbidities, socioeconomic factors, and hospital/admission factors.

RESULTS

From 48,316,430 maternal hospitalizations, 34,001 (0.07%) were complicated by PR-AKI. Hospitalizations for PR-AKI increased from 3.5/10,000 hospitalizations in 2005 to 11.8/10,000 hospitalizations in 2015 with the largest increase seen in patients aged ≥35 and black patients. PR-AKI was associated with higher odds of miscarriage (adjusted odds ratio [aOR], 1.64; 95% CI, 1.34 to 2.07) and mortality (aOR, 1.53; 95% CI, 1.25 to 1.88). After adjustment for age, medical comorbidities, and socioeconomic factors, blacks were more likely than whites to develop PR-AKI (aOR, 1.17; 95% CI, 1.04 to 1.33). On subgroup analyses in hospitalizations of patients with PR-AKI, blacks and Hispanics were more likely to have preeclampsia/eclampsia compared with whites (aOR, 1.29; 95% CI, 1.01 to 1.65; and aOR, 1.69; 95% CI, 1.23 to 2.31, respectively). Increased odds of mortality in PR-AKI compared with whites were only seen in black patients (aOR, 1.61; 95% CI, 1.02 to 2.55).

CONCLUSIONS

The incidence of PR-AKI has increased and the largest increase was seen in older patients and black patients. PR-AKI is associated with miscarriages, adverse discharge from hospital, and mortality. Black and Hispanic patients with PR-AKI were more likely to have adverse outcomes than white patients. Further research is needed to identify factors contributing to these discrepancies.

Correction of morphofunctional disorders of the cardiovascular system with asialized erythropoietin and arginase II selective inhibitors KUD 974 and KUD 259 in experimental preeclampsia

Introduction: Preeclampsia remains one of the most common causes of maternal and perinatal mortality worldwide. A significant role in the pathogenesis of this pathology is assigned to placental ischemia and endothelial dysfunction. Therefore, the aim of the present study was to study the effectiveness of asialized erythropoietin and arginase II selective inhibitors: KUD-259 and KUD-974 in the correction of morphofunctional disorders of the cardiovascular system in experimental preeclampsia.

Materials and methods: The study was performed in 260 female Wistar rats, each weighing 250–300 g. An ADMA-like preeclampsia was reproduced in the experiment. To assess the emerging morphofunctional disorders, the following parameters were used: blood pressure, coefficient of endothelial dysfunction, microcirculation in the placenta, proteinuria, fluid content in the omentum, concentration of terminal metabolites in the blood plasma, and morphometric parameters of fetuses.

Results and discussion: The administration of arginase II selective inhibitor KUD-974 in combination with asialized erythropoietin leads to a pronounced correction of emerging changes: a decrease in systolic and diastolic blood pressure in 1.5 and 1.7 times, a decrease in proteinuria in 3.6 times and a decrease in fluid content in the omentum. When arginase II selective inhibitor KUD 974 and asialized erythropoietin are used with methyldopa, the positive effects of the former are enhanced.

Conclusion: Arginase II selective inhibitors KUD-259 and KUD-974 and asialized erythropoietin have a pronounced positive effect on the correction of morphofunctional disorders in animals with ADMA-like preeclampsia.

Sex differences in redox homeostasis in renal disease

Sex differences in redox signaling in the kidney present new challenges and opportunities for understanding the physiology and pathophysiology of the kidney. This review will focus on reactive oxygen species, immune-related signaling pathways and endothelin-1 as potential mediators of sex-differences in redox homeostasis in the kidney. Additionally, this review will highlight male-female differences in redox signaling in several major cardiovascular and renal disorders namely acute kidney injury, diabetic nephropathy, kidney stone disease and salt-sensitive hypertension. Furthermore, we will discuss the contribution of redox signaling in the pathogenesis of postmenopausal hypertension and preeclampsia.

Acute kidney injury associated with preeclampsia or hemolysis, elevated liver enzymes, and low platelets syndrome

OBJECTIVE

To determine the prevalence of acute kidney injury (AKI), placental abruption and postpartum hemorrhage in patients with preeclampsia or HELLP syndrome.

STUDY DESIGN

A retrospective study of patients with preeclampsia or HELLP syndrome treated at the University of Mississippi Medical Center from January 2000 through December 2010.

MAIN OUTCOME MEASURES

Relationships among the obstetric complications of placental abruption, postpartum hemorrhage, and AKI (serum creatinine >107 µmol/L) of women with preeclampsia or HELLP syndrome. Additional analysis was undertaken to explore if there was a correlation between postpartum hemorrhage/placental abruption and the severity of HELLP syndrome according to the Mississippi classification system.

RESULTS

Data from 1276 women over 11 years were included in the analysis. 67 of 466 patients (14.4%) with HELLP syndrome and 38 of 810 preeclampsia patients (4.7%) met criteria for AKI. Women with either placental abruption or postpartum hemorrhage had statistically significant increased odds of also having AKI (p < 0.01). Women with HELLP and AKI were also more likely to experience either placental abruption or postpartum hemorrhage. Women with Class 1 HELLP with placental abruption or postpartum hemorrhage were also more likely to have AKI than women with preeclampsia.

CONCLUSION

HELLP syndrome, AKI and placental abruption or postpartum hemorrhage appear to be interrelated. AKI occurs more frequently in women with HELLP syndrome with or without associated postpartum hemorrhage and placental abruption.