Outcome of infants born to women with chronic kidney disease

Kidney disease and reproductive health

Understanding the relationship between reproductive health and kidney function is important to provide holistic care for people living with kidney disease. Chronic kidney disease (CKD) has negative impacts on both male and female fertility owing to factors including inflammation, hormonal dysregulation, reduced ovarian reserve, reduced sperm quality and sexual dysfunction. However, pregnancy is achievable for most cisgender women with kidney disease, including kidney transplant recipients and patients on dialysis. CKD in pregnancy is associated with health risks to the mother and child, including increased risk of progression of kidney disease, hypertensive complications of pregnancy, and neonatal complications including fetal growth restriction, preterm birth and stillbirth. However, with appropriate pre-pregnancy counselling, fertility assessment and support, health optimization, and evidence-based antenatal care, the majority of patients will achieve a good outcome. Medication safety should be reviewed before and during pregnancy and lactation, weighing the risk of disease flare against potential adverse effects on the offspring. Important areas for further research include the optimal timing of delivery and the short- and long-term cardiovascular and renal impacts of pregnancy in patients with CKD, as well as long-term kidney and cardiovascular outcomes in their offspring.

Neonatal Outcomes of Infants Born to Women on Hemodialysis: A Single-Center, Case-Control Study

OBJECTIVE

 The study aimed to investigate the neonatal outcomes of infants born to mothers on hemodialysis.

STUDY DESIGN

 This retrospective, case-control, and observational study included 17 infants born to 16 mothers on dialysis in 2003 to 2016. We compared their clinical characteristics to those of 51 gestational age- and sex-matched control infants. Statistical comparisons were made between the two groups by using the Wilcoxon-Mann-Whitney test for continuous variables and the Chi-square test or Fisher's exact test for categorical variables.

RESULTS

 Of the 16 pregnancies of mothers on dialysis, 15 (94%) deliveries were premature (<37 weeks), and 16/17 (94%) infants survived to discharge. The incidences of neonatal complications, such as intraventricular hemorrhage, bronchopulmonary dysplasia, patent ductus arteriosus, and periventricular leukomalacia, were not significantly different between the groups. However, 5/17 (29%) of the infants had congenital anomalies.

CONCLUSION

 Although infants born to mothers on dialysis have a high risk of prematurity, they do not have any additional risk of neonatal complications, except for congenital anomalies. The potential risk of congenital anomalies should be investigated further.

KEY POINTS

· Preterm birth rate among mothers on hemodialysis was 94%.. · Complications in these infants were similar to controls.. · Twenty-nine percent of infants had congenital anomalies..

Twin pregnancy in a patient on chronic haemodialysis who already had three pregnancies

Pregnancy in women with end-stage renal disease is rare. Multiple pregnancies carry a high risk of complications even in healthy individuals. We report the case of a 36-year-old woman who had four pregnancies while she was on dialysis, including one twin pregnancy. The last pregnancy occurred while in the 14th year of hemodialysis. At 8 weeks of gestation (WG), ultrasonography diagnosed a dichorionic diamniotic twin pregnancy. The frequency of dialysis was increased from 3 to 6 times a week and each session lasted 4 h. At 22 WG, polyhydramnios was diagnosed. At 25 WG, the patient presented respiratory distress and was transferred to intensive care where continuous hemodialysis, non-invasive ventilation, antibiotic and tocolysis were initiated. Because of tocolysis failure, a cesarean section was performed and she delivered male twins. The two newborns weighed 790 and 870 g, respectively. To our knowledge, this is the first report of four pregnancies in hemodialysis including one twin pregnancy. The incidence of pregnancy and a better outcome in patients on hemodialysis has increased in recent years but a tight coordination between nephrologists and obstetricians is essential.

A best-practice position statement on pregnancy after kidney transplantation: focusing on the unsolved questions. The Kidney and Pregnancy Study Group of the Italian Society of Nephrology

Kidney transplantation (KT) is often considered to be the method best able to restore fertility in a woman with chronic kidney disease (CKD). However, pregnancies in KT are not devoid of risks (in particular prematurity, small for gestational age babies, and the hypertensive disorders of pregnancy). An ideal profile of the potential KT mother includes "normal" or "good" kidney function (usually defined as glomerular filtration rate, GFR ≥ 60 ml/min), scant or no proteinuria (usually defined as below 500 mg/dl), normal or well controlled blood pressure (one drug only and no sign of end-organ damage), no recent acute rejection, good compliance and low-dose immunosuppression, without the use of potentially teratogen drugs (mycophenolic acid and m-Tor inhibitors) and an interval of at least 1-2 years after transplantation. In this setting, there is little if any risk of worsening of the kidney function. Less is known about how to manage "non-ideal" situations, such as a pregnancy a short time after KT, or one in the context of hypertension or a failing kidney. The aim of this position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology is to review the literature and discuss what is known about the clinical management of CKD after KT, with particular attention to women who start a pregnancy in non-ideal conditions. While the experience in such cases is limited, the risks of worsening the renal function are probably higher in cases with markedly reduced kidney function, and in the presence of proteinuria. Well-controlled hypertension alone seems less relevant for outcomes, even if its effect is probably multiplicative if combined with low GFR and proteinuria. As in other settings of kidney disease, superimposed preeclampsia (PE) is differently defined and this impairs calculating its real incidence. No specific difference between non-teratogen immunosuppressive drugs has been shown, but calcineurin inhibitors have been associated with foetal growth restriction and low birth weight. The clinical choices in cases at high risk for malformations or kidney function impairment (pregnancies under mycophenolic acid or with severe kidney-function impairment) require merging clinical and ethical approaches in which, beside the mother and child dyad, the grafted kidney is a crucial "third element".

Pregnancy in Women With CKD: A Success Story

In women with chronic kidney disease (CKD), pregnancy outcomes have improved over the last 50 years, particularly in the developed world. Maternal mortality is now extremely low, fetal survival has markedly increased (even in women with CKD stages 4-5), and it is now the exception for women with CKD to be advised against embarking on a pregnancy. However, pregnancies are rarely free from complications, and there are unanswered questions about the longer term effects on maternal and infant health. The developments have led to a more optimistic attitude to pregnancy in women with CKD not requiring renal replacement treatment. The remaining problems are described in this World Kidney Forum.

A best practice position statement on pregnancy in chronic kidney disease: the Italian Study Group on Kidney and Pregnancy

Pregnancy is increasingly undertaken in patients with chronic kidney disease (CKD) and, conversely, CKD is increasingly diagnosed in pregnancy: up to 3 % of pregnancies are estimated to be complicated by CKD. The heterogeneity of CKD (accounting for stage, hypertension and proteinuria) and the rarity of several kidney diseases make risk assessment difficult and therapeutic strategies are often based upon scattered experiences and small series. In this setting, the aim of this position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature, and discuss the experience in the clinical management of CKD in pregnancy. CKD is associated with an increased risk for adverse pregnancy-related outcomes since its early stage, also in the absence of hypertension and proteinuria, thus supporting the need for a multidisciplinary follow-up in all CKD patients. CKD stage, hypertension and proteinuria are interrelated, but they are also independent risk factors for adverse pregnancy-related outcomes. Among the different kidney diseases, patients with glomerulonephritis and immunologic diseases are at higher risk of developing or increasing proteinuria and hypertension, a picture often difficult to differentiate from preeclampsia. The risk is higher in active immunologic diseases, and in those cases that are detected or flare up during pregnancy. Referral to tertiary care centres for multidisciplinary follow-up and tailored approaches are warranted. The risk of maternal death is, almost exclusively, reported in systemic lupus erythematosus and vasculitis, which share with diabetic nephropathy an increased risk for perinatal death of the babies. Conversely, patients with kidney malformation, autosomal-dominant polycystic kidney disease, stone disease, and previous upper urinary tract infections are at higher risk for urinary tract infections, in turn associated with prematurity. No risk for malformations other than those related to familiar urinary tract malformations is reported in CKD patients, with the possible exception of diabetic nephropathy. Risks of worsening of the renal function are differently reported, but are higher in advanced CKD. Strict follow-up is needed, also to identify the best balance between maternal and foetal risks. The need for further multicentre studies is underlined.

[Pregnancy and kidney transplantation: report of 10 cases]

La grossesse chez les patientes transplantées rénales est à risque de complications maternelles mais surtout fœtales. Le risque de survenue de rejet aigue ou chronique inhérent à la grossesse est faible. L'objectif de notre étude était de rapporter les grossesses survenues chez nos transplantées rénales, leurs aspects évolutifs et une revue de la littérature. L’âge moyen des patientes au moment de la transplantation rénale était de 28,5 ans. Le traitement immunosuppresseur d'entretien a associé une corticothérapie, l'azathioprine et/ou la ciclosporine A. Le délai moyen entre la transplantation rénale et la découverte de la grossesse était de 6,5 ans. L’âge moyen au moment de la conception était de 33,8 ans. Il n'ya pas eu de modifications du traitement immunosuppresseur au cours de la grossesse. La créatininémie moyenne au cours de la grossesse était stable à 104,8 µmol/l avec une créatininémie supérieure à 150 µmol/l dans 2 cas. Les complications maternelles au cours de la grossesse étaient une hypertension artérielle gravidique dans 3 cas, une protéinurie dans 3 cas, une ascension de la créatininémie au 7ème mois dans 2 cas, une cholestase hépatique gravidique dans 2 cas et une hyperuricémie dans 4 cas. Une prématurité était observée dans 3 cas en rapport avec une rupture prématurée des membranes, des contractions utérines sur utérus cicatriciel et des signes de prééclampsie dans le troisième cas. Après l'accouchement, Une hypertension artérielle était observée chez 3 patientes. On n'a pas noté de rejet aigu chez nos patientes. La créatininémie moyenne était de 195,3 µmol/l (74- 553 µmol/l). Le développement statural et psychomoteur était normal pour 9 enfants. La bonne évolution des grossesses chez les patientes transplantées rénales une planification et un suivi régulier.

Association of low-protein supplemented diets with fetal growth in pregnant women with CKD

BACKGROUND AND OBJECTIVES

Women affected by CKD increasingly choose to get pregnant. Experience with low-protein diets is limited. The aim of this study was to review results obtained from pregnant women with CKD on supplemented vegan-vegetarian low-protein diets.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a single-arm, open intervention study between 2000-2012 of a low-protein diet in pregnant patients with stages 3-5 CKD or severe proteinuria (>1 g/d in the first trimester or nephrotic at any time). Stages 3-5 CKD patients who were not on low-protein diets for clinical, psychologic, or logistic reasons served as controls. The setting was the Obstetrics-Nephrology Unit dedicated to kidney diseases in pregnancy. The treated group included 24 pregnancies--21 singleton deliveries, 1 twin pregnancy, 1 abortion, and 1 miscarriage. Additionally, there were 21 controls (16 singleton deliveries, 5 miscarriages). The diet was a vegan-vegetarian low-protein diet (0.6-0.8 g/kg per day) with keto-acid supplementation and 1-3 protein-unrestricted meals allowed per week.

RESULTS

Treated patients and controls were comparable at baseline for median age (35 versus 34 years), referral week (7 versus 8), eGFR (59 versus 54 ml/min), and hypertension (43.5% versus 33.3%); median proteinuria was higher in patients on the low-protein diet (1.96 [0.1-6.3] versus 0.3 [0.1-2.0] g/d; P<0.001). No significant differences were observed in singletons with regard to gestational week (34 versus 36) or Caesarean sections (76.2% versus 50%). Kidney function at delivery was not different, but proteinuria was higher in the diet group. Incidence of small for gestational age babies was significantly lower in the diet group (3/21) versus controls (7/16; chi-squared test; P=0.05). Throughout follow-up (6 months to 10 years), hospitalization rates and prevalence of children below the third percentile were similar in both groups.

CONCLUSION

Vegan-vegetarian supplemented low-protein diets in pregnant women with stages 3-5 CKD may reduce the likelihood of small for gestational age babies without detrimental effects on kidney function or proteinuria in the mother.

Kidney disease in pregnancy: (Women's Health Series)

Kidney disease and pregnancy may exist in two general settings: acute kidney injury that develops during pregnancy, and chronic kidney disease that predates conception. In the first trimester of pregnancy, acute kidney injury is most often the result of hyperemesis gravidarum, ectopic pregnancy, or miscarriage. In the second and third trimesters, the common causes of acute kidney injury are severe preeclampsia, hemolysis-elevated liver enzymes-low platelets syndrome, acute fatty liver of pregnancy, and thrombotic microangiopathies, which may pose diagnostic challenges to the clinician. Cortical necrosis and obstructive uropathy are other conditions that may lead to acute kidney injury in these trimesters. Early recognition of these disorders is essential to timely treatment that can improve both maternal and fetal outcomes. In women with preexisting kidney disease, pregnancy-related outcomes depend upon the degree of renal impairment, the amount of proteinuria, and the severity of hypertension. Neonatal and maternal outcomes in pregnancies among renal transplant patients are generally good if the mother has normal baseline allograft function. Common renally active drugs and immunosuppressant medications must be prescribed, with special considerations in pregnant patients.

What about the renal function during childhood of children born from dialysed mothers?

INTRODUCTION

Pregnancy during dialysis is a high-risk condition which is becoming more and more common. The renal outcome of children born from such pregnancies needs to be investigated since renal development may be affected (i.e. exposure to uraemic toxins, therapies, intermittent haemodynamic changes during sessions, prematurity, growth retardation).

METHODS

We performed a single-centre prospective global and renal evaluation (inulin clearance or 2009 Schwartz formula in children <4 years) in 10 children from 7 mothers who underwent haemodialysis during pregnancy.

RESULTS

The median (range) age of mothers at the beginning of pregnancy was 30 (22-33) years, with maximal weekly haemodialysis duration of 18 (12-30) h. Systemic arterial hypertension was reported in 4 of 10 pregnancies, polyhydramnios in 3 and oligohydramnios in 1. The median (range) gestational age was 32 (29-39) weeks of gestation (WG). Seven children were born before 36 WG. The median (range) birth weight (BW) was 1735 (930-3430)g, and eight children had a BW <2500 g. One child had a PAX2 mutation requiring early renal transplantation and was thus excluded from further analysis. Even though glomerular filtration rate and blood pressure were normal in all other children, a significant urine albumin-to-creatinine ratio was found in three children and an increased urine beta-2-microglobulin concentration in an additional one, questioning the presence of an underlying silent reduction in nephron number.

CONCLUSIONS

Despite the small number of patients, this pilot study highlights the potential risk of renal impairment in children born from dialysed mothers. Further studies are required but until then, careful monitoring of these children is important.

Pregnancy outcomes in women with chronic kidney disease: a systematic review

BACKGROUND AND OBJECTIVES

Pregnant women with chronic kidney disease (CKD) are at risk of adverse maternal and fetal outcomes. We conducted a systematic review of observational studies that described this risk.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We searched several databases from their date of inception through June 2010 for eligible articles published in any language. We included any study that reported maternal or fetal outcomes in at least five pregnant women in each group with or without CKD. We excluded pregnant women with a history of transplantation or maintenance dialysis.

RESULTS

We identified 13 studies. Adverse maternal events including gestational hypertension, pre-eclampsia, eclampsia, and maternal mortality were reported in 12 studies. There were 312 adverse maternal events among 2682 pregnancies in women with CKD (weighted average of 11.5%) compared with 500 events in 26,149 pregnancies in normal healthy women (weighted average of 2%). One or more adverse fetal outcomes such as premature births, intrauterine growth restriction, small for gestational age, neonatal mortality, stillbirths, and low birth weight were reported in nine of the included studies. Overall, the risk of developing an adverse fetal outcome was at least two times higher among women with CKD compared with those without.

CONCLUSIONS

This review summarizes current available evidence to guide physicians in their decision-making, advice, and care for pregnant women with CKD. Additional studies are needed to better characterize the risks.