The National Transplantation Pregnancy Registry: comparison between pregnancy outcomes in diabetic cyclosporine -treated female kidney recipients and CyA-treated female pancreas-kidney recipients

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.

Pregnancy in pancreas-kidney transplant recipients: report of three cases and review of the literature

Seventy-three pregnancies in 43 women with SPK have now been described by the US National Transplantation Pregnancy Registry (NTPR) (established in 1991), which contains self-reported data from questionnaires and hospital records. These women have high rates of complications despite normoglycaemia and restoration of renal function. We describe the pregnancies of three SPK recipients in the UK managed in joint renal obstetric clinics and discuss the antenatal and postnatal complications specific to SPK transplants.

Effects on T-cell maturation and proliferation induced by lactational transfer of cyclosporine to nursing pups

BACKGROUND

Pregnancy after allotransplantations is becoming a more common occurrence, and the immunosuppressant of choice is cyclosporine (CsA) for these patients. Consequently, the effect of CsA on prenatal and postnatal immune development and function in the infant is an increasingly important clinical issue. The purpose of this study was to evaluate the potential problems of maternal CsA exposure on neonatal T-cell maturation and proliferation after lactational transfer of CsA in an animal model.

METHODS

CsA was administered daily (subcutaneous) for 20 days during lactation, beginning the day of parturition using two dose levels (15 and 25 mg/kg body weight/day) in conjunction with saline controls.

RESULTS

Considerable amounts of CsA were passed to the newborn rats with neonatal blood levels equal to that of the mothers for the 25-mg/kg/day dose and 55% for the 15 mg/kg dose. There was a significant reduction in thymus/body-weight ratio and thymus cellularity for the pups born to mothers dosed at 15 or 25 mg/kg/day of CsA. The thymus from the CsA-exposed pups showed an almost complete loss of the medullary region with no apparent change in the thymic cortex. The CsA-treated mothers and their pups (15 and 25 mg/kg/day dose) had a significant increase in the percentage of CD4+CD8+ thymocytes and a significant decrease in the percentages of CD4+, CD3hi, and T-cell receptor (TCR)hi thymocyte phenotype subsets and CD4/CD8 ratios. Thymocyte proliferative responses to concanavalin A + interleukin-2 were also significantly decreased in the mother and pup after both doses of CsA. In contrast to the mothers that showed no change in splenocyte proliferative responses, their pups showed decreased responses at both the 15- and 25-mg/kg doses. All immune alterations due to CsA lactational exposure in the pups were back to control levels after 30 days of postweaning CsA cessation.

CONCLUSIONS

This study clearly demonstrates that neonatal exposure to CsA via lactational transfer can cause significant alterations in T-cell maturation and inhibition of lymphoproliferative responsiveness to mitogen activation. Although the CsA blood level in human transplant patients is normally much lower, this data indicate a potential for increased risk to opportunistic infections due to altered immune components in babies exposed to long-term CsA.

Reproductive hormones after pancreas transplantation

BACKGROUND

Reproductive hormone function after pancreas transplantation (PTX) is unknown as it has not been studied.

METHODS

We prospectively studied PTX recipients to determine changes in reproductive hormones after PTX. Testosterone or estradiol, leutinizing hormone, follicle stimulating hormone, and prolactin were determined before and 1 year after PTX in 23 patients (10 women, 13 men) followed for more than 1 year after PTX. Of these, 11 received simultaneous kidney-PTX; 8 PTX only; and 4, PTX after kidney. Average age was 38.4+/-1.6 years and average duration of diabetes was 24.5+/-1.3 years. Nine (four women, five men) patients had been on dialysis pre-PTX. Sixteen of 23 patients were treated with cyclosporine and seven with FK-506 along with prednisone and azathioprine post-PTX.

RESULTS

Mean testosterone in men was normal pre- and post-PTX. Two men had secondary hypogonadism pre-PTX with resolution in one and persistence in the other post-PTX. Five of the ten women had evidence of hypogonadism pre-PTX: three had primary hypogonadism and two had secondary hypogonadism. Post-PTX, 7 of 10 women had abnormal reproductive hormones: 4 had primary hypogonadism, 2 had secondary hypogonadism, and 1 developed hyperestrogenemia with elevated estradiol (482 pg/ml) and leutinizing hormone (41 IU/liter). Mean prednisone dose and cyclosporine trough level were higher in the women than the men (P<0.05). No cases of secondary hypogonadism that developed or resolved post-PTX were related to changes in prolactin, renal function, or hyperglycemia.

CONCLUSIONS

Women are more likely than men to have reproductive hormone abnormalities pre- and post-PTX and the causes may be multiple.

Drug safety issues in pregnancy following transplantation and immunosuppression: effects and outcomes

Successful pregnancy outcomes are possible after solid organ transplantation. While there are risks to mother and fetus, there has not been an increased incidence of malformations noted in the newborn of the transplant recipient. It is essential that there is closely coordinated care that involves the transplant team and an obstetrician in order to obtain a favourable outcome. Current data from the literature, as well as from reports from the National Transplantation Pregnancy Registry (NTPR), support the concept that immunosuppression be maintained at appropriate levels during pregnancy. At present, most immunosuppressive maintenance regimens include combination therapy, usually cyclosporin or tacrolimus based. Most female transplant recipients will be receiving maintenance therapy prior to and during pregnancy. For some agents, including monoclonal antibodies and mycophenolate mofetil, there is either no animal reproductive information or there are concerns about reproductive safety. The optimal (lowest risk) transplant recipient can be defined by pre-conception criteria which include good transplant graft function, no evidence of rejection, minimum 1 to 2 years post-transplant and no or well controlled hypertension. For these women pregnancy generally proceeds without significant adverse effects on mother and child. It is of note that the epidemiological data available to date on azathioprine-based regimens are favourable in the setting of a category D agent (i.e. one that can cause fetal harm). Thus, there is still much to learn regarding potential toxicities of immunosuppressive agents. The effect of improved immunosuppressive regimens which use newer or more potent (and potentially more toxic) agents will require further study.

Pancreas and pancreas-kidney transplantation

Pancreas transplantation consistently results in an insulin-independent normoglycemic state in insulin-dependent diabetic recipients. Registry data show insulin independence is achieved in 80% of simultaneous kidney and pancreas recipients, more than 70% of pancreas after kidney recipients, and more than 60% of nonuremic pancreas transplant alone recipients. Advances in immunosuppression and careful monitoring for rejection in conjunction with biopsies are largely responsible for improved results. However, complications do occur, and improvements in surgical technique and patient care continue to evolve.

Medical management of the pregnant transplant recipient

Retrospective analyses of pregnancies in female renal transplant recipients including case reports, center reports, and questionnaire surveys have, for the most part, reached similar conclusions. In the presence of adequate, stable graft function, these high-risk pregnancies are generally well tolerated, but the majority of the liveborn outcomes are premature and many of the newborns are low birthweight. Obstetrical complications such as preeclampsia and cesarean section occur in a significant proportion of cases. With improvements in methods of data acquisition and computer technology, the aim for the future must be enhanced communication between transplant centers on a prospective basis, perhaps comparing cases with patient profiles derived from analyzed databases such as the National Transplantation Pregnancy Registry (NTPR). Continued efforts to identify prepregnancy risk factors as well as optimal antenatal management strategies will help to further improve pregnancy outcomes in this population. Discussed in this review are reports from the literature as well as current data from the NTPR focusing on the medical management of pregnancy in the renal transplant recipient.