Pregnancy in IgA nephropathy

Chronic Kidney Disease and Pregnancy

Women with chronic kidney disease (CKD) are at risk for adverse pregnancy-associated outcomes, including progression of their underlying renal dysfunction, a flare of their kidney disease, and adverse pregnancy complications such as preeclampsia and preterm delivery. Earlier-stage CKD, as a rule, is a safer time to have a pregnancy, but even women with end-stage kidney disease have attempted pregnancy in recent years. As such, nephrologists need to be comfortable with pregnancy preparation and management at all stages of CKD. In this article, we review the renal physiologic response to pregnancy and the literature with respect to both expected maternal and fetal outcomes among young women at various stages of CKD, including those who attempt to conceive while on dialysis. The general management of young women with CKD and associated complications, including hypertension and proteinuria are discussed. Finally, the emotional impact these pregnancies may have on young women with a chronic disease and the potential benefits of care in a multidisciplinary environment are highlighted.

Pregnancy and Glomerular Disease: A Systematic Review of the Literature with Management Guidelines

During pregnancy, CKD increases both maternal and fetal risk. Adverse maternal outcomes include progression of underlying renal dysfunction, worsening of urine protein, and hypertension, whereas adverse fetal outcomes include fetal loss, intrauterine growth restriction, and preterm delivery. As such, pregnancy in young women with CKD is anxiety provoking for both the patient and the clinician providing care, and because the heterogeneous group of glomerular diseases often affects young women, this is an area of heightened concern. In this invited review, we discuss pregnancy outcomes in young women with glomerular diseases. We have performed a systematic review in attempt to better understand these outcomes among young women with primary GN, we review the studies of pregnancy outcomes in lupus nephritis, and finally, we provide a potential construct for management. Although it is safe to say that the vast majority of young women with glomerular disease will have a live birth, the counseling that we can provide with respect to individualized risk remains imprecise in primary GN because the existing literature is extremely dated, and all management principles are extrapolated primarily from studies in lupus nephritis and diabetes. As such, the study of pregnancy outcomes and management strategies in these rare diseases requires a renewed interest and a dedicated collaborative effort.

Pregnancy and Kidney Outcomes in Patients With IgA Nephropathy: A Cohort Study

BACKGROUND

The outcomes of pregnancy in immunoglobulin A nephropathy (IgAN) are controversial. This cohort study assessed the effects of pregnancy on kidney disease progression and risk factors for adverse pregnancy outcomes in patients with IgAN.

STUDY DESIGN

A cohort study.

SETTING & PARTICIPANTS

Women of child-bearing age with IgAN and minimum follow-up of 1 year after biopsy from December 2003 to September 2014.

PREDICTORS

Pregnancy, treated as a time-dependent variable; baseline (at time of biopsy) estimated glomerular filtration rate (eGFR), proteinuria, blood pressure, and kidney pathology (Oxford MEST classification).

OUTCOMES

Kidney disease progression event, defined as 30% decline in eGFR or end-stage kidney disease; rate of eGFR decline; and adverse pregnancy outcomes, including severe preeclampsia and fetal loss.

RESULTS

Of 413 patients enrolled, 266 (64.4%), 101 (24.5%), 40 (9.6%), and 6 (1.5%) had chronic kidney disease (CKD) stages 1, 2, 3, and 4, respectively. During follow-up, 104 had 116 pregnancies, of which 110 continued beyond week 20; 309 patients did not become pregnant. After adjustment for age, eGFR, mean arterial pressure, proteinuria, and pathology class at the time of biopsy, subsequent pregnancy among patients with CKD stages 3 to 4, but not CKD stages 1 to 2, was associated with faster eGFR decline (-7.44 vs -3.90mL/min/1.73m² per year; P=0.007) and increased incidence of kidney progression events (HR, 5.14; 95% CI, 1.16-22.74) compared with patients who did not become pregnant.

LIMITATIONS

Relatively small sample size and single-center experience.

CONCLUSIONS

Pregnancy accelerated kidney disease progression in women with IgAN and CKD stage 3, but not in those at stage 1 or 2.

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 across the spectrum of chronic kidney disease

Management of the pregnant woman with chronic kidney disease is difficult for both nephrologists and obstetricians. Prepregnancy counselling with respect to risk stratification, optimization of maternal health prior to pregnancy, as well as management of the many potential pregnancy-associated complications in this complex patient population remains challenging due to the paucity of large, well-designed clinical studies. Furthermore, the heterogeneity of disease and the relative infrequency of pregnancy, particularly in more advanced stages of chronic kidney disease, leaves many clinicians feeling ill prepared to manage these pregnancies. As such, counselling is imprecise and management varies substantially across centers. All pregnancies in women with chronic kidney disease can benefit from a collaborative multidisciplinary approach with a team that consists of nephrologists experienced in the management of kidney disease in pregnancy, maternal-fetal medicine specialists, high-risk pregnancy nursing staff, dieticians, and pharmacists. Further access to skilled neonatologists and neonatal intensive care unit support is essential given the risks for preterm delivery in this patient population. The goal of this paper is to highlight some of the data that currently exist in the literature, provide management strategies for the practicing nephrologist at all stages of chronic kidney disease, and explore some of the knowledge gaps where future multinational collaborative research efforts should concentrate to improve pregnancy outcomes in women with kidney disease across the globe.

A Systematic Review and Meta-Analysis of Outcomes of Pregnancy in CKD and CKD Outcomes in Pregnancy

BACKGROUND AND OBJECTIVES

We undertook a systematic review and meta-analysis of published cohort studies and case-control studies to estimate (1) the risk of pregnancy complications among patients with CKD versus those without CKD and (2) the risk of CKD progression among pregnant patients versus nonpregnant controls with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We searched electronic databases for studies published between 1946 and 2014, and we reviewed articles using validity criteria. Random-effects analytical methods were used.

RESULTS

Twenty-three studies (14 with data for adverse pregnancy outcomes and 9 for renal outcomes) with 506,340 pregnancies were included. Pregnancy with CKD had greater odds of preeclampsia (odds ratio [OR], 10.36; 95% confidence interval [95% CI], 6.28 to 17.09), premature delivery (OR, 5.72; 95% CI, 3.26 to 10.03), small for gestational age/low birth weight (OR, 4.85; 95% CI, 3.03 to 7.76), cesarean section (OR, 2.67; 95% CI, 2.01 to 3.54), and failure of pregnancy (OR, 1.80; 95% CI, 1.03 to 3.13). Subgroup analysis showed that odds of preeclampsia (P<0.01) and premature delivery (P<0.01) were higher in women with nondiabetic nephropathy compared with diabetic nephropathy, and the odds of preeclampsia (P=0.01) and premature delivery (P<0.01) were higher in women with macroproteinuria compared with microproteinuria. The median for follow-up time for renal events was 5 years (interquartile range, 5-14.7 years). There were no significant differences in the occurrence of renal events between CKD pregnant women and those without pregnancy (OR, 0.96; 95% CI, 0.69 to 1.35). Subgroup analysis showed that publication year, sample size, follow-up years, type of primary disease, CKD classification, level of serum creatinine at baseline, proteinuria, and level of systolic BP did not modify the renal outcomes.

CONCLUSIONS

The risks of adverse maternal and fetal outcomes in pregnancy are higher for women with CKD versus pregnant women without CKD. However, pregnancy was not a risk factor for progression of renal disease in women with CKD before pregnancy.

Effect of Pregnancy and Delivery on the Renal Function and the Prognosis of Patients with Chronic Kidney Disease Stage 3 Caused by Immunoglobulin A Nephropathy

OBJECTIVE

Immunoglobulin A nephropathy (IgAN) exhibits a peak onset that coincides with the reproductive age. Therefore, many young women with IgAN may become pregnant. However, the outcome of pregnancy in women with renal diseases remains controversial, and the characteristics and outcome of pregnancy in IgAN patients must be further evaluated.

METHODS

A prospective follow-up study of 64 pregnant women with IgAN was performed by analyzing the laboratory data and prognosis. To clarify the influence of renal insufficiency, we compared these patients according to the chronic kidney disease (CKD) stage with special attention to CKD stage 3 [N=16 in total, N=9 for estimated glomerular filtration rate (eGFR) ≥45 mL/min, N=7 for <45 mL/min].

RESULTS

We found that pregnancy and delivery did not produce any significant changes in the renal function for patients with CKD stage 3 (≥45 mL/min) at five years after delivery, although proteinuria was elevated at 30 weeks of pregnancy and at three months after delivery. However, only for patients with CKD stage 3 (<45 mL/min) was there a significant deterioration in the eGFR at five years after delivery. Additionally, the data of pregnant women with CKD stage 3 were compared with those of 22 nonpregnant women with similar clinical and demographic characteristics.

CONCLUSION

Pregnant patients with IgAN (CKD stage 3, eGFR ≥45 mL/min) did not exhibit any significant reduction in the renal function at five years after delivery as compared with the baseline, which was similar to the findings in nonpregnant patients. Thus, while pregnancy with CKD stage 3 (eGFR ≥45 mL/min) was not a risk factor, patients with CKD stage 3 (eGFR <45 mL/min) showed a worsened renal function five years after delivery.

Chronic kidney disease in pregnancy

Parturients with renal insufficiency or failure present a significant challenge for the anesthesiologist. Impaired renal function compromises fertility and increases both maternal and fetal morbidity and mortality. Close communication amongst medical specialists, including nephrologists, obstetricians, neonatologists and anesthesiologists is required to ensure the safety of mother and child. Pre-existing diseases should be optimized and close surveillance of maternal and fetal condition is required. Kidney function may deteriorate during pregnancy, necessitating early intervention. The goal is to maintain hemodynamic and physiologic stability while the demands of the pregnancy change. Drugs that may adversely affect the fetus, are nephrotoxic or are dependent on renal elimination should be avoided.

[Pregnancy and kidney diseases]

The prevalence of chronic kidney disease in women of childbearing age reaches approximately 0.2%. Under physiological conditions pregnancy results in important hemodynamic changes on the maternal organism. In the case of chronic kidney disease these adaptations often are only partial. Physiological changes of immune response during pregnancy may contribute to the progress of renal disease. Regardless of the underlying kidney disease, one can assume that the better the glomerular filtration rate and blood pressure are the more favorable the course of pregnancy will be with the chance for a healthy child and stable renal function. To achieve this goal, a close interaction is required between gynecologist, nephrologist, and other specialists in a center with appropriate experience.

Pregnancy outcome in women with chronic kidney disease: a prospective cohort study

OBJECTIVE

To evaluate pregnancy outcome in women with chronic kidney disease (CKD) or proteinuria in early pregnancy with concomitant risk for preeclampsia (PE).

METHODS

Thirty-six women with CKD (Cr > 100 μmol/L at booking or Cr > 125 μmol/L prepregnancy or proteinuria ≥ 500 mg/24 hours at booking) and 30 women with proteinuria (≥2+) and known clinical risk for PE were enrolled at 14(+0) to 21(+6) weeks. Pregnancy outcomes were assessed.

RESULTS

Women with mild CKD (prepregnancy Cr < 125 µmol/Cr > 100 µmol at booking; n = 22) had high rates of preeclampsia (40%), preterm delivery (<37 weeks' gestation; 54%), SGA infants (<10th adjusted centile; 64%)and perinatal death (5%). Women with moderate/severe CKD (prepregnancy creatinine > 125 µmol; n = 14) had poor perinatal outcomes: preterm delivery (86%) and perinatal death (14%). Women with proteinuria (≥2+) and concomitant risk of PE also had high rates of pre-eclampsia (60%), preterm delivery (40%), and SGA infants (27%).

CONCLUSIONS

Pregnancy complications for women with CKD remain high. Women with risk factors for PE with proteinuria (≥2+) at booking are also high-risk.

Management of renal disease in pregnancy

Although renal disease in pregnancy is uncommon, it poses considerable risk to maternal and fetal health. This article discusses renal physiology and assessment of renal function in pregnancy and the effect of pregnancy on renal disease in patients with diabetes, lupus, chronic glomerulonephritis, polycystic kidney disease, and chronic pyelonephritis. Renal diseases occasionally present for the first time in pregnancy, and diagnoses of glomerulonephritis, acute tubular necrosis, hemolytic uremic syndrome, and acute fatty liver of pregnancy are described. Finally, therapy of end-stage renal disease in pregnancy, dialysis, and renal transplantation are reviewed.

GLOMERULONEPHRITIS AND THE NEPHROTIC SYNDROME IN PREGNANCY

Glomerulonephritis (GN) may be manifest clinically in several ways. It may be asymptomatic and associated with only minor urinary dipstick abnormalities, GN may present with one of the classic renal nephritic or nephrotic syndromes, or may be associated with progressive chronic kidney disease with hypertension and the gradual development of uraemia, or it may present with fulminating life threatening illness with severe acute kidney injury. The development of GN may indicate a primary renal limited disease, or may be secondary in association with systemic diseases such as systemic lupus erythematosus (SLE), myeloma, infections or diabetes. Although immunological abnormalities underlie the development of many forms of GN, precise pathogenic mechanisms remain unclear and diagnostic labels may simply reflect a description of the glomerular histological changes observed (Table 1).

Pregnancy outcome in patients with insulin dependent diabetes mellitus and diabetic nephropathy treated with ACE inhibitors before pregnancy

The preconception and intrapregnancy parameters that are relevant to outcome in women with insulin dependent diabetes mellitus (IDDM) and diabetic nephropathy remain controversial. We analyzed the types and frequencies of maternal and neonatal complications in 24 IDDM patients with diabetic nephropathy (24 pregnancies), all with preserved to mildly impaired renal function. All patients received treatment with captopril for at least six months prior to planned pregnancy and were maintained under strict glycemic control from at least three months before pregnancy to delivery. A successful pregnancy outcome (live, healthy infant without severe handicaps two years after delivery) was observed in 87.5% of the patients. Preexisting hypertension was the only parameter found to be significantly predictive of an unsuccessful outcome (p = 0.0004). We conclude that in patients with IDDM complicated by diabetic nephropathy, pre-pregnancy captopril treatment combined with strict glycemic control offers a prolonged protective effect against possible renal deterioration and probably improves pregnancy outcome.

Outcome of pregnancy in women with glomerular diseases

Over the last 16 years the evolution of 24 pregnancies in 17 women with biopsy-proven glomerular disease was analyzed. The underlying renal histology was IgA nephropathy in 8 cases, lupus nephritis in 7, mesangiocapillary glomerulonephritis type I in 1, and focal segmental glomerulosclerosis in 1. All but 2 had normal renal function before conception and 3 were hypertensive. Fetal survival rate was 75%. There were 6 preterm deliveries (33.3%), 3 newborns small for gestational age (17%), 1 stillbirth, and 5 therapeutic abortions. The perinatal mortality was 5.5%. De novo hypertension occurred in 8 pregnancies (33.3%). In 11 pregnancies (46%) increased proteinuria was diagnosed and in 6 (25%) a decline in maternal renal function was recorded. Permanent impairment of renal function was seen in 2 women with renal insufficiency before conception. Maternal hypertension and renal function impairment were associated more frequently with obstetric complications. In conclusion, pregnancy is safe for normotensive mothers with glomerular diseases and normal renal function. Hypertension and impaired renal function at conception seem to carry increased risk for mothers and fetuses. Low-dose immunosuppressive treatment during pregnancy is not harmful for the fetus.

Proteinuria: a risk factor for pregnancy-related renal function decline in primary glomerular disease?

Pregnancy may be followed by a postpartum acceleration of renal function loss in patients with renal disease. We retrospectively analyzed the effects of pregnancy on progressive renal function decline, and the risk factors for an acceleration, in a group of 19 renal disease patients with 30 pregnancies and a group of 31 patients who did not become pregnant after onset of glomerular disease. The rate of renal function loss was calculated for each patient by linear regression on reciprocal serum creatinine values over 11 years' follow-up. Multiple regression analysis showed that both pregnancy (P = 0.03) and initial proteinuria (P = 0.005) were independently related with the rate of renal function loss. Such a relation could not be observed with histologic diagnosis, and initial age, renal function, blood pressure, and serum albumin. Further analysis showed that 10 of 30 pregnancies are followed by a predefined acceleration of renal function loss. These pregnancies were preceded and complicated by a higher proteinuria (4.1 v 1.7 g/d, P < 0.005; and 3.6 v 2.1 g/d, P < 0.05, respectively) compared with the other 20 pregnancies that are not followed by such an acceleration. In conclusion, patients with primary glomerular disease complicated by substantial proteinuria are at risk for acceleration of renal function decline after pregnancy.

Gestation in women with kidney disease: prognosis and management

Physicians may be called upon to guide patients with renal disease on the advisability of conceiving or maintaining a gestation, or to manage pregnancies permitted to continue. The prevailing view is that the degree of functional impairment and the presence or absence of hypertension prior to conception determine both pregnancy outcome and the effect of gestation on the natural history of the kidney disorder (Table 3). Normotensive women with minimal dysfunction have a greater than 90% chance of success and there is little evidence that gestation will adversely affect the disease. Presence of hypertension increases the complications rate substantially if not aggressively controlled, and prognosis is also poorer in women with moderate renal dysfunction. Most gestations in the latter group succeed, but at considerable maternal risk: over 20% of these women experience renal functional deterioration, and 30-40% of them have major problems with hypertension. Thus we tend not to recommend pregnancy in patients with moderate renal insufficiency, and definitely discourage gestation when GFR is severely impaired. We advise termination, as most of these gestations fail, and maternal risk is substantial. There are a number of diseases in which pregnancy should not be undertaken, including scleroderma and periarteritis. Some authors believe that women with membranoproliferative glomerulonephritis also do poorly, and opinions differ on the effects of gestation on IgA nephropathy, focal glomerulosclerosis, and reflux nephropathy. Table 4 summarizes our view concerning pregnancy in a number of specific renal disorders. Finally, in addition to the controversies noted above, there are other unresolved problems requiring further study. For instance, protein restriction should be avoided until the effect of this therapeutic manoeuvre on fetal development is evaluated. Also needed are conclusive studies on whether or not the physiological hyperfiltration of human pregnancy affects adversely pre-existing renal disease.

Nail-patella syndrome and pre-eclampsia

We present here the first described case of Nail-patella syndrome (NPS) and pregnancy. Complications occurred during the pregnancy with the onset of preeclampsia at 22 weeks, leading to intrauterine fetal death at 24 weeks. The nephropathy of the NPS began clinically during the course of gestation. Postpartum, it persisted as isolated proteinuria, which became a nephrotic syndrome 18 months later.

The kidney in hypertensive pregnancies--victim and villain

Many changes in renal function occur in normal pregnancy. Without a proper understanding of these changes, routine clinical investigations may easily be misinterpreted. Women with preeclampsia have further alterations in renal function and, in occasional cases, develop acute renal failure. Understanding of abnormal renal physiology and hormonal changes in these women allows the clinician to interpret biochemical tests appropriately and make proper use of vasodilator therapy with careful attention to volume homeostasis. Women who undertake pregnancy with a primary renal disease, most commonly glomerulonephritis or reflux nephropathy, have a higher risk of adverse fetal and maternal outcomes. Awareness of these risks provides a basis for proper preconceptual counseling, as well as careful monitoring of maternal blood pressure and renal function and fetal growth during such pregnancies. These strategies will optimize the chances of a successful pregnancy outcome for both mother and baby.