Chronic kidney disease in preeclamptic patients: not found unless searched for—Is a nephrology evaluation useful after an episode of preeclampsia?

A systematic review on the determinants of long-term kidney sequelae after hypertensive diseases of pregnancy

INTRODUCTION

Preeclampsia is a pregnancy syndrome defined by high blood pressure (≥140/90 mmHg) and at least one other associated complication, including proteinuria, maternal organ dysfunction, or uteroplacental dysfunction, after 20 weeks of gestation. The long-term effects of this disease on the kidneys are still not fully understood. This systematic review aimed to evaluate the risk of chronic kidney disease after preeclampsia and the determinants of these sequelae.

MATERIAL AND METHODS

We included observational studies on kidney outcomes from cohorts of women with a history of preeclampsia from the PubMed, Web of Science, and Cochrane databases.

RESULTS

Two hundred and seventy-seven articles were evaluated. Thirty-one (published between 2000 and 2022) were included in this systematic review. Twenty-two authors focused on the risk of chronic kidney disease and/or persistent proteinuria. Five authors found a more significant risk of kidney disease after preeclampsia, with a risk ranging from two to three times higher. Regarding end-stage kidney disease, most studies found a risk of between 4 and 14 times higher of developing end-stage kidney disease after preeclampsia. For several authors, early preeclampsia, preterm delivery, and recurrent pregnancies complicated by preeclampsia seemed to be the three major factors for determining the risk of kidney sequelae or proteinuria.

CONCLUSIONS

Women with a history of preeclampsia have a greater risk of chronic kidney disease or end-stage kidney disease. Some determinants seem to increase the risk. Further research is required to identify these determinants of kidney sequelae.

The ABCs of post-preeclampsia outpatient nephrology care: the Le Mans strategy

Preeclampsia and hypertensive disorders of pregnancy complicate 3 to 5% of all pregnancies. Chronic kidney disease (CKD), at any stage, reportedly affects 3% of women in childbearing age but most of the time is underdiagnosed, especially in asymptomatic early stages. The link between preeclampsia/hypertensive disorders of pregnancy and CKD is bidirectional and women experiencing a preeclampsia/hypertensive disorder of pregnancy episode are at higher risk for developing CKD later in life, as well as metabolic and cardiovascular diseases. In turn, CKD is a risk factor for preeclampsia/hypertensive disorders of pregnancy. Thus, it is important to follow up patients after an episode of preeclampsia/hypertensive disorders of pregnancy in order to make a timely diagnosis of CKD or reduce the risk of another episode of preeclampsia/hypertensive disorder of pregnancy during a subsequent pregnancy. In Le Mans, we set up a dedicated outpatient clinic for women who experienced an episode of preeclampsia/hypertensive disorder of pregnancy. In this point of view paper, we present how we manage post-preeclampsia, in the hope that sharing this experience can promote the creation of dedicated outpatient clinics in other settings that will contribute to women's health.

Management of hypertensive disorders in pregnancy: a Position Statement of the European Society of Hypertension Working Group 'Hypertension in Women'

Hypertensive disorders in pregnancy (HDP), remain the leading cause of adverse maternal, fetal, and neonatal outcomes. Epidemiological factors, comorbidities, assisted reproduction techniques, placental disorders, and genetic predisposition determine the burden of the disease. The pathophysiological substrate and the clinical presentation of HDP are multifarious. The latter and the lack of well designed clinical trials in the field explain the absence of consensus on disease management among relevant international societies. Thus, the usual clinical management of HDP is largely empirical. The current position statement of the Working Group 'Hypertension in Women' of the European Society of Hypertension (ESH) aims to employ the current evidence for the management of HDP, discuss the recommendations made in the 2023 ESH guidelines for the management of hypertension, and shed light on controversial issues in the field to stimulate future research.

Proteinuria in predicting adverse outcomes in women with severe features of pre-eclampsia from a developing country: A prospective cohort study

OBJECTIVE

To study the adverse maternal and perinatal outcomes in women with severe pre-eclampsia (SPE) among different ranges of proteinuria.

METHODS

This prospective cohort study was conducted in Jawaharlal Institute of Postgraduate Medical Education and Research, India. After obtaining informed written consent, the 202 singleton women fulfilling the criteria of severe features of pre-eclampsia were stratified based on the value of urine protein-creatinine ratio (UPCR) as mild, moderate, severe, and massive proteinuria during pregnancy. Clinical outcomes were assessed and patients were followed up until 12 weeks postpartum to identify persistent proteinuria and hypertension.

RESULTS

Of the 202 women with SPE, adverse maternal outcomes were seen in 34.65% (n = 70) and adverse perinatal outcomes in 75.74% (n = 153). The demographic and clinical factors were similar among women with increasing severity of proteinuria, except for mean systolic blood pressure, serum creatinine and total serum protein. UPCR was found to have a significant correlation with composite adverse perinatal outcome (P < 0.001) and individual outcomes of neonatal intensive care unit admission for >48 h (P = 0.01) and neonatal sepsis (P = 0.02) but not adverse maternal outcomes (P = 0.201). The optimum UPCR cutoff for adverse perinatal outcomes was 1.6 (sensitivity, 73.2%; specificity, 52.7%). In addition, 14.85% of the women had a persistently elevated UPCR and 3.96% had hypertension at 3 months postpartum.

CONCLUSION

In women with SPE, severe and massive proteinuria were related to composite adverse perinatal outcome but not composite adverse maternal outcome. Moreover, antenatal 24-h proteinuria was significantly associated with persistent proteinuria. Significant proteinuria in women with SPE poses a risk for chronic renal dysfunction, requiring follow-up.

Adding creatinine to routine pregnancy tests: a decision tree for calculating the cost of identifying patients with CKD in pregnancy

BACKGROUND

Even in its early stages, chronic kidney disease (CKD) is associated with adverse pregnancy outcomes. The current guidelines for pregnancy management suggest identifying risk factors for adverse outcomes but do not mention kidney diseases. Since CKD is often asymptomatic, pregnancy offers a valuable opportunity for diagnosis. The present analysis attempts to quantify the cost of adding serum creatinine to prenatal screening and monitoring tests.

METHODS

The decision tree we built takes several screening scenarios (before, during and after pregnancy) into consideration, following the hypothesis that while 1:750 pregnant women are affected by stage 4-5 CKD and 1:375 by stage 3B, only 50% of CKD cases are known. Prevalence of abortions/miscarriages was calculated at 30%; compliance with tests was hypothesized at 50% pre- and post-pregnancy and 90% during pregnancy (30% for miscarriages); the cost of serum creatinine (production cost) was set at 0.20 euros. A downloadable calculator, which makes it possible to adapt these figures to other settings, is available.

RESULTS

The cost per detected CKD case ranged from 111 euros (one test during pregnancy, diagnostic yield 64.8%) to 281.90 euros (one test per trimester, plus one post-pregnancy or miscarriage, diagnostic yield 87.7%). The best policy is identified as one test pre-, one during and one post-pregnancy (191.80 euros, diagnostic yield 89.4%).

CONCLUSIONS

This study suggests the feasibility of early CKD diagnosis in pregnancy by adding serum creatinine to routinely performed prenatal tests and offers cost estimates for further discussion.

The Ethanolic Extract of Gomphrena celosioides Mart. Does Not Alter Reproductive Performance or Embryo-Fetal Development, nor Does It Cause Chromosomal Damage

Gomphrena celosioides is a native Brazilian plant found in the State of Mato Grosso do Sul. It is used in folk medicine to treat kidney diseases, skin diseases, infections, rheumatism, gastrointestinal diseases, and respiratory diseases. It is also used as an abortifacient. To evaluate the effects of the ethanolic extract of Gomphrena celosioides (EEGc) on reproductive performance, embryo development, and chromosome stability, Swiss mice were randomly divided into experimental groups (n = 10). The animals in the control group received the vehicle Tween 80-1% in the proportion of 0.1 mL/10 g of body weight orally, from the first to the 18th gestational day. The animals in the treatment groups received the EEGc (100, 1000, and 2000 mg/kg) from the first to the 18th gestational day. The animals underwent evaluations of their reproductive performance and embryofetal development. The results showed that the EEGc did not change the animals' final weight, weight gain, uterine weight, or net weight gain. The evaluation showed that the absolute and relative organs' weights did not vary between the different experimental groups. In addition, the EEGc did not change the numbers of implants, live fetuses, dead fetuses, or fetal resorptions. There were no differences in post-operative loss rates, implantations, or resorptions, nor were there differences in fetal viability or sex ratio. The use of the EEGc did not result in different frequencies of malformations. In addition, the EEGc did not alter the frequency of chromosomal damage or frequency of micronuclei. Based on our findings, we considered the extract of Gomphrena celosioides to be safe for use during pregnancy, although some parameters indicated caution in its use.

What a paediatric nephrologist should know about preeclampsia and why it matters

Preeclampsia is a protean syndrome causing a kidney disease characterised by hypertension and proteinuria, usually considered transitory and reversible after delivery. Its prevalence ranges from 3-5 to 10% if all the related disorders are considered. This narrative review, on behalf of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology, focuses on three reasons why preeclampsia should concern paediatric nephrologists and how they can play an important role in its prevention, as well as in the prevention of future kidney and cardiovascular diseases. Firstly, all diseases of the kidney and urinary tract diagnosed in paediatric age are associated with a higher risk of adverse pregnancy-related outcomes, including preeclampsia. Secondly, babies with low birth weights (small for gestational age, born preterm, or both) have an increased risk of developing the full panoply of metabolic diseases (obesity, hypertension, early-onset cardiopathy and chronic kidney disease) and girls are at higher risk of developing preeclampsia when pregnant. The risk may be particularly high in cases of maternal preeclampsia, highlighting a familial aggregation of this condition. Thirdly, pregnant teenagers have a higher risk of developing preeclampsia and the hypertensive disorders of pregnancy, and should be followed up as high risk pregnancies. In summary, preeclampsia has come to be seen as a window on the future health of both mother and baby. Identification of subjects at risk, early counselling and careful follow-up can contribute to reducing the high morbidity linked with this disorder.

The Hypertensive Disorders of Pregnancy: A Focus on Definitions for Clinical Nephrologists

About 5-10% of pregnancies are complicated by one of the hypertensive disorders of pregnancy. The women who experience these disorders have a greater risk of having or developing kidney diseases than women with normotensive pregnancies. While international guidelines do not provide clear indications for a nephrology work-up after pregnancy, this is increasingly being advised by nephrology societies. The definitions of the hypertensive disorders of pregnancy have changed greatly in recent years. The objective of this short review is to gather and comment upon the main definitions of the hypertensive disorders of pregnancy as a support for nephrologists, who are increasingly involved in the short- and long-term management of women with these disorders.

Preeclampsia is a valuable opportunity to diagnose chronic kidney disease: a multicentre study

Background

Pre-eclampsia (PE) and chronic kidney disease (CKD) are known to be associated. Our objective was to assess the prevalence of CKD in a large multicentre cohort of women without acknowledged CKD who experienced a PE episode.

Methods

The setting for the study was France (Le Mans, Central France) and Italy (Cagliari, Sardinia). The study participants were patients who experienced PE in 2018–19, identified from the obstetric charts. Patients with known–acknowledged CKD were excluded. Only singletons were considered. Persistent (micro)albuminuria was defined as present and confirmed at least 3 months after delivery. CKD was defined according to the Kidney Disease Outcomes Quality Initiative guidelines; urinary alterations or low eGFR confirmed at a distance of at least 3 months, or morphologic changes. Patients were divided into four groups: evidence of CKD; no evidence of CKD; unclear diagnosis-ongoing work-up; or persistent microalbuminuria. The outcome ‘diagnosis of CKD’ was analysed by simple and multiple logistic regressions. Temporal series (week of delivery) were analysed with Kaplan–Meier curves and Cox analysis.

Results

Two hundred and eighty-two PE pregnancies were analysed (Le Mans: 162; Cagliari: 120). The incidence of CKD diagnosis was identical (Le Mans: 19.1%; Cagliari: 19.2%); no significant difference was found in unclear-ongoing diagnosis (6.2%; 5.8%) and microalbuminuria (10.5%; 5.8%). Glomerulonephritis and diabetic nephropathy were more frequent in Cagliari (higher age and diabetes prevalence), and interstitial diseases in Le Mans. In the multivariate logistic regression, CKD diagnosis was associated with preterm delivery (adjusted P = 0.035). Gestation was 1 week shorter in patients diagnosed with CKD (Kaplan–Meier P = 0.007). In Cox analysis, CKD remained associated with shorter gestation after adjustment for age and parity.

Conclusions

The prevalence of newly diagnosed CKD is high after PE (19% versus expected 3% in women of childbearing age), supporting a systematic nephrology work-up after PE.

Maternal and fetal outcomes of urolithiasis: A retrospective cohort study

OBJECTIVES

Although urolithiasis is relatively common in the general population, there is limited information on this condition available in the pregnant population. The objectives of this study are to identify the incidence of urolithiasis in pregnancy, as well as to compare maternal and fetal outcomes associated with urolithiasis in pregnancy.

METHODS

Using the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database from the United States, a population-based retrospective cohort study consisting of pregnant women who delivered between 1999 and 2015 was conducted. ICD-9-CM code 592.X was used to identify pregnant women with urolithiasis within the cohort, with pregnant women without urolithiasis forming the comparison group. Unconditional logistic regression models were used to estimate the associations between urolithiasis in pregnancy and maternal and neonatal outcomes, while adjusting for baseline maternal characteristics.

RESULTS

A cohort of 13,792,544 pregnant women was identified, of which 11,528 had a urolithiasis-related admission during pregnancy, for an overall incidence of 8.3 per 10,000 pregnancies. Women with urolithiasis had a greater risk of developing preeclampsia/eclampsia, OR 1.35(95% CI 1.24-1.47), gestational diabetes, 1.29(1.20-1.30), abruptio placenta, 1.41(1.22-1.64), placenta previa, 1.55(1.27-1.90), pyelonephritis, 88.87(81.69-96.69), venous thromboembolism, 1.65(1.23-2.22), and more likely to deliver by cesarean, 1.20(1.15-1.25). As well, maternal death was more common among these women, 2.85(1.07-7.60). Congenital anomalies, 2.84(2.43-3.31) and prematurity, 1.92(1.82-2.03) were more commonly found among babies born to women with urolithiasis.

CONCLUSION

Although the mechanism is unclear, women with urolithiasis in pregnancy have an increased risk of adverse pregnancy and newborn outcomes.

Quality or Quantity of Proteins in the Diet for CKD Patients: Does "Junk Food" Make a Difference? Lessons from a High-Risk Pregnancy

BACKGROUND

How to manage patients with severe kidney disease in pregnancy is still a matter of discussion, and deciding if and when to start dialysis is based on the specialist's experience and dialysis availability. The effect of toxic substances usually cleared by the kidney may be more severe and readily evident. The review, and related case, underlines the importance of considering the presence of additives in food in delicate conditions, such as CKD pregnancy. The Case: A 39-year-old indigenous woman from a low-resourced area in Mexico was referred to the obstetric nephrology at 25 gestational weeks because of serum creatinine at 3.6 mg/dL, hypertension on low-dose alpha-methyl-dopa, and nephrotic-range proteinuria. Kidney ultrasounds showed small poorly differentiated kidneys; foetal ultrasounds detected a female foetus, normal for gestational age. The patient's baseline protein intake, which was estimated at 1.2-1.3 g/kg/day, was mostly of animal-origin (>70%) poor-quality food ("junk food"). In the proposed diet, protein intake was only slightly reduced (1.0-1.2 g/kg/day), but the source of proteins was changed (only 30% of animal origin) with attention to food quality. A remarkable decrease in BUN was observed, in concomitance with adequate dietary follow-up, with rapid rise of BUN when the patient switched temporarily back to previous habits. A healthy female baby weighing 2,460 g (11th centile for gestational age) was delivered at 37 gestational weeks. Discussion and Literature Review: While data on patients with chronic kidney disease are scant, the long list of contaminants present in food, especially if of low quality, should lead us to reflect on their potential negative effect on kidney function and make us realize that eating healthy, unprocessed "organic" food should be encouraged, in delicate conditions such as pregnancy and breastfeeding and for young children, in particular when kidney function is failing. The case herein described gave us the opportunity to reflect on the importance of diet quality and on the potential risks linked to food additives, many of which, including phosphates and potassium, are not declared on food labels, while others, including dyes, antioxidants, thickeners, emulsifiers, and preservatives, are qualitatively, but not quantitatively, reported.

Nephrotic syndrome due to preeclampsia before 20 weeks of gestation: a case report

Background

Preeclampsia (PE) refers to the development of hypertension and new-onset proteinuria or progressive organ damage (especially kidney) in a previously normotensive pregnant women after 20 weeks of gestation. Thus, new-onset nephrotic syndrome due to PE before 20 weeks of gestation seems to be rare, making its diagnosis difficult in this time period.

Case presentation

A 28-year-old woman presented with a new-onset nephrotic syndrome at 16 weeks of gestation. A high dose of oral glucocorticoids (prednisolone, 40 mg) was initiated for presumed glomerulonephritis since she presented with severe nephrotic syndrome before 20 weeks of gestation, however, the treatment was not effective. At 21 weeks of gestation, we confirmed that the soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio was very high (sFlt-1, 13,400 pg/mL; PlGF, 21.9 pg/mL; serum sFlt-1/PlGF ratio 611.9). Therefore, we diagnosed nephrotic syndrome due to PE, and oral glucocorticoids were discontinued. After she underwent a cesarean section at 24 weeks & 3 days, we performed a kidney biopsy. Focal segmental sclerotic lesions with epithelial cell hyperplasia and foam cells in the tubular poles were seen on light microscopy. On immunofluorescence tests, C4d staining showed linear peripheral patterns in the glomeruli. Electron microscopy revealed diffuse subendothelial edema with focal foot process effacement. The histological diagnosis was severe glomerular endotheliosis with focal segmental glomerulosclerosis. Furthermore, the histology of placenta was consistent with PE. Eight months after delivery, her proteinuria disappeared completely.

Conclusions

We not only confirmed an abnormal serum sFlt-1/PlGF ratio but also presented the histology compatible with pure PE in the kidney and placenta in a case of nephrotic syndrome before 20 weeks of gestation. The serum sFlt-1/PlGF ratio may be useful in determining the treatment strategy for atypical cases of pregnant women with nephrotic syndrome, particularly before 20 weeks of gestation.

Contraception in chronic kidney disease: a best practice position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology

Even though fertility is reduced, conception and delivery are possible in all stages of CKD. While successful planned pregnancies are increasing, an unwanted pregnancy may have long-lasting deleterious effects, hence the importance of birth control, an issue often disregarded in clinical practice. The evidence summarized in this position statement is mainly derived from the overall population, or other patient categories, in the lack of guidelines specifically addressed to CKD. Oestroprogestagents can be used in early, non-proteinuric CKD, excluding SLE and immunologic disorders, at high risk of thromboembolism and hypertension. Conversely, progestin only is generally safe and its main side effect is intramestrual spotting. Non-medicated intrauterine devices are a good alternative; their use needs to be carefully evaluated in patients at a high risk of pelvic infection, even though the degree of risk remains controversial. Barrier methods, relatively efficacious when correctly used, have few risks, and condoms are the only contraceptives that protect against sexually transmitted diseases. Surgical sterilization is rarely used also because of the risks surgery involves; it is not definitely contraindicated, and may be considered in selected cases. Emergency contraception with high-dose progestins or intrauterine devices is not contraindicated but should be avoided whenever possible, even if far preferable to abortion. Surgical abortion is invasive, but experience with medical abortion in CKD is still limited, especially in the late stages of the disease. In summary, personalized contraception is feasible, safe and should be offered to all CKD women of childbearing age who do not want to get pregnant.