ACUTE RENAL FAILURE OF OBSTETRIC ORIGIN: AN ANALYSIS OF 70 PATIENTS

Acute renal morbidities with obstetrical emergencies: An important women health issue

OBJECTIVE

To observe the impact of acute renal morbidities with obstetrical emergencies on maternal health.

METHODS

In this study pregnant women between 28-40 weeks gestational period and delivered women in their puerperal period up to 42 days after delivery having acute renal problems associated with obstetrical emergencies were included. Pregnant and delivered women with obstetrical emergencies and associated other morbidities were excluded. These women were registered on the predesigned proforma after taking written informed consent and taking approval from institutional ethic research committee. The data was collected and analyzed on SPSS version 21.

RESULT

Out of these 196 total registered women, majority of these women 81(41.32%) were between 21-30 years of age and multiparous women with parity four and above were 83(42.34%). Commonest presenting symptoms were generalized oedema 123(62.75%) and oligouria 92(46.93%). Frequent obstetrical emergencies observed were pre-eclampsia 53(27.04%), post partum haemorrhage 48(24.48%) and ante partum haemorrhage 36(18.36%) women. The complete recovery was observed in 86(43.87%) women, while mortality was seen in 56(28.57%) women.

CONCLUSION

Renal morbidities were more frequently observed in obstetrical emergencies leading to high morbidity and mortality rate.

Changing picture of renal cortical necrosis in acute kidney injury in developing country

Renal cortical necrosis (RCN) is characterized by patchy or diffuse ischemic destruction of all the elements of renal cortex resulting from significantly diminished renal arterial perfusion due to vascular spasm and microvascular injury. In addition, direct endothelial injury particularly in setting of sepsis, eclampsia, haemolytic uremic syndrome (HUS) and snake bite may lead to endovascular thrombosis with subsequent renal ischemia. Progression to end stage renal disease is a rule in diffuse cortical necrosis. It is a rare cause of acute kidney injury (AKI) in developed countries with frequency of 1.9%-2% of all patients with AKI. In contrast, RCN incidence is higher in developing countries ranging between 6%-7% of all causes of AKI. Obstetric complications (septic abortion, puerperal sepsis, abruptio placentae, postpartum haemorrhage and eclampsia) are the main (60%-70%) causes of RCN in developing countries. The remaining 30%-40% cases of RCN are caused by non-obstetrical causes, mostly due to sepsis and HUS. The incidence of RCN ranges from 10% to 30% of all cases of obstetric AKI compared with only 5% in non-gravid patients. In the developed countries, RCN accounts for 2% of all cases of AKI in adults and more than 20% of AKI during the third trimester of pregnancy. The reported incidence of RCN in obstetrical AKI varies between 18%-42.8% in different Indian studies. However, the overall incidence of RCN in pregnancy related AKI has decreased from 20%-30% to 5% in the past two decades in India. Currently RCN accounts for 3% of all causes of AKI. The incidence of RCN in obstetrical AKI was 1.44% in our recent study. HUS is most common cause of RCN in non-obstetrical group, while puerperal sepsis is leading cause of RCN in obstetric group. Because of the catastrophic sequelae of RCN, its prevention and aggressive management should always be important for the better renal outcome and prognosis of the patients.

Renal cortical necrosis is a disappearing entity in obstetric acute kidney injury in developing countries: our three decade of experience from India

RATIONAL

Obstetrical complications are the commonest causes of Renal Cortical Necrosis (RCN). However, the overall incidence of RCN in obstetric acute kidney injury in developing countries has been decreasing in recent years.

OBJECTIVE

The aim of this study was to evaluate the changing profile of RCN in obstetric AKI over the last three decades.

METHODS

This single center study included patients with biopsy proven renal cortical necrosis over a period of 32 years from 1982 to 2014. The diagnosis of RCN was suspected in patients with prolonged AKI (>4 weeks) with absolute anuria in the setting of hemorrhage, hypotension and sepsis; and was confirmed by renal biopsy. The changing pattern in the incidence, etiology and outcome of RCN in patients with obstetric AKI was compared in the three study periods, namely 1982-1991, 1992-2002 and 2003-2014.

RESULTS

Over a period of 32 years, RCN was diagnosed in 15/259(5.8%) cases of obstetric AKI. Diffuse and patchy cortical necrosis were noted in 8(53.3%) and 7(46.7%) patients, respectively. RCN occurred in 17%(11/65), 2.4%(3/125) and 1.44%(1/69) patients in 1982-1991, 1992-2002 and 2003-2014, respectively. Septic abortion was commonest cause of RCN in the first two study periods but no case was observed in last decade. The decrease in incidence of RCN over the three decades was statistically significant (p-value < 0.001). Maternal mortality decreased to zero in 2003-2014 from 72.7% in 1982-1991.

CONCLUSIONS

The incidence of RCN in obstetric AKI in developing countries has declined low enough to label it as a disappearing entity.

The kidney in pregnancy: A journey of three decades

The spectrum of kidney disease occurring during pregnancy includes preeclampsia, hypertensive disorders of pregnancy, urinary tract infection, acute kidney injury, and renal cortical necrosis (RCN). Preeclampsia affects approximately 3-5% of pregnancies. We observed preeclampsia in 5.8% of pregnancies, and 2.38% of our preeclamptic women developed eclampsia. Severe preeclampsia and the eclampsia or hemolysis, elevated liver enzymes levels, and low platelets count (HELLP) syndrome accounted for about 40% of cases of acute kidney injury (AKI) in pregnancy. Preeclampsia/eclampsia was the cause of acute renal failure (ARF) in 38.3% of the cases. Preeclampsia was the most common (91.7%) cause of hypertension during pregnancy, and chronic hypertension was present in 8.3% of patients. We observed urinary tract infection (UTI) in 9% of pregnancies. Sepsis resulting from pyelonephritis can progress to endotoxic shock, disseminated intravascular coagulation, and AKI. The incidence of premature delivery and low birth weight is higher in women with UTI. The incidence of AKI in pregnancy with respect to total ARF cases has decreased over the last 30 years from 25% in 1980s to 5% in 2000s. Septic abortion-related ARF decreased from 9% to 3%. Prevention of unwanted pregnancy and avoidance of septic abortion are key to eliminate abortion-associated ARF in early pregnancy. The two most common causes of ARF in third trimester and postpartum periods were puerperal sepsis and preeclampsia/HELLP syndrome. Pregnancy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome and acute fatty liver of pregnancy were rare causes of ARF. Despite decreasing incidence, AKI remains a serious complication during pregnancy.

Spectrum of renal cortical necrosis in acute renal failure in eastern India

Renal cortical necrosis is an uncommon cause of acute renal failure. We report 23 cases of biopsy-proven renal cortical necrosis which constituted 6.3% (23/363) of all cases of acute renal failure studied over a period of seven years (1985-92). The patients were divided into two groups: obstetric and non-obstetric. Obstetric complications were responsible for renal cortical necrosis in 15 (65.2%) patients while non-obstetric conditions accounted for the remaining eight (34.8%) cases. The overall incidence of cortical necrosis in obstetric acute renal failure was 15/63 (23.8%) patients, the incidence being nearly equal in early (20.5%) and late (29%) pregnancy. Post-abortum renal failure was the sole cause of cortical necrosis in early pregnancy in the obstetric group. Haemolytic uraemic syndrome (three patients) and septicaemia (two patients) were the main cause of necrosis in the non-obstetric group. The cortical necrosis was diffuse and patchy in 17 and six patients, respectively. The disease had a fatal prognosis in 20 (87%) patients; mortality was due to uraemic complications and infections in the majority of patients. The high frequency of post-abortum renal cortical necrosis in our patients is similar to the experience of other Indian workers.

Acute renal failure in pregnancy in South Africa

This study compares our experiences of the incidence and etiology of acute renal failure in pregnancy (ARF-P) in patients requiring hemodialysis, a decade after a previous publication from our institution. A retrospective analysis of the hospital records of 42 patients with a diagnosis of ARF-P during a 3-year period from 1990 to 1992 was undertaken [16% of the total number of acute renal failure (ARF) patients needing hemodialysis]. The incidence of ARF-P (expressed relative to all cases of acute renal failure requiring hemodialysis) decreased from 24.6% (1978) to 16% (1992: p = 0.03). Preeclampsia-eclampsia (PE:E) replaced septic abortion as the principal cause of ARF-P. In those patients with PE:E, thrombocytopenia (platelet count < 150 x 10(9)/L) occurred in all, while 33% developed the HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets). Ingestion of herbal toxins was noted mostly in patients with septic abortion. Maternal mortality was 5% and was due to multiorgan failure complicating septic abortion. The perinatal mortality of 55% occurred in women with early gestation, thrombocytopenia, and high serum creatinine levels. Acute renal failure in pregnancy continues to present a challenge in South Africa, a developing country. There were significantly more obstetric than gynecological causes in 1992 (p = 0.0003). This could be attributed to the steady decline in septic abortion since 1978. The main contributor to obstetric-related causes was PE:E. Greater emphasis should therefore be placed on detecting hypertension at antenatal visits.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute renal failure in pregnancy

Acute renal failure (ARF) has become a very rare complication of pregnancy. This results from the virtual disappearance of septic abortion ARF and from the improvement of prenatal care, including the prevention of volume contraction which is mainly due to uterine haemorrhage, early diagnosis, and treatment of other classic maternal complications such as pre-eclampsia and acute pyelonephritis. The incidence of bilateral renal cortical necrosis has also been declining during the last decade. Acute fatty liver, a potentially fatal disease, is often complicated by ARF. Early recognition of this disorder, with prompt termination of pregnancy and intensive supportive therapy, can reduce fetal and maternal mortality rate. The syndrome of idiopathic postpartum renal failure is also associated with a high morbidity and mortality. Beyond supportive treatment, including haemodialysis or peritoneal dialysis and the use of potent antihypertensive drugs to control blood pressure and blood transfusion if necessary, specific therapy as plasma infusion, plasma exchange and antiplatelet drugs may be of value. Both peritoneal dialysis and haemodialysis may be used in gravidas with ARF. Early 'prophylactic' dialysis should be applied to pregnant women. Careful monitoring of fluid balance and anticoagulation is necessary during dialysis.

Acute renal cortical necrosis--a study of 113 patients

Over a 28-year period, 113 out of 2986 (3.8%) patients dialysed for acute renal failure at a referral center in North India were diagnosed to have acute renal cortical necrosis (ACN). Obstetric causes were responsible for ACN in 56.6% patients and nonobstetric causes in 43.4%. Within the obstetric group, ACN developed in association with complications of late pregnancy in 37.1% and following septic abortion in 19.5%. The various nonobstetric causes included viperine snake bite in 14.2%, hemolytic uremic syndrome in 11.5%, renal allograft rejection in 5.3%, acute gastroenteritis in 4.4%, acute pancreatitis in 3.5%, septicemia in 2.7%, and trauma and drug-induced IV hemolysis in 0.9% patients. Total anuria was the commonest presenting feature and was noted in 78.8% of patients. Renal histology showed diffuse cortical necrosis in 62.8% and patchy lesions in 37.2% patients. Computerized tomography (CT scan) of the kidneys revealed characteristic diagnostic findings in all the 5 patients in whom it was done. Dialytic support could be withdrawn as a result of improvement in renal function in 19 patients with patchy cortical necrosis. Dialysis-free survival of as long as 12 years has been recorded. The present study shows that, in contrast to the Western world, ACN continues to be a common cause of acute renal failure in developing countries. CT scan of the kidneys is helpful in establishing an early diagnosis.

Acute renal failure in pregnancy

Between 1982 and 1992, 18 cases of pregnancy-related acute renal failure (PR-ARF) were observed (9% of the total number of ARF). Mean age of the women was 32 years (22-40 years). Uterine hemorrhage and preeclampsia/eclampsia were the major causes of ARF, accounting for 61% of the cases. Patchy renal cortical necrosis was suspected in 2 cases whereas signs of disseminated intravascular coagulation (DIC) or microangiopathic hemolytic anemia were present in 6 (33%) and 9 (50%) cases, respectively. Ten women required hemodialysis; and 6 of them, additional plasma exchange sessions. Five patients (28%) died during the acute phase of the illness, mainly due to brain damage, hepatic failure, and sepsis. Among the survivors, a complete (61.5%) or partial recovery (23.1%) was usually seen, but irreversible renal failure was recorded in 2 cases with postpartum hemolytic uremic syndrome (HUS). Short-lasting oligoanuria (< 3 days) represents a good prognostic index. However, the presence of vascular injury (cortical necrosis, HUS) seems to carry a poor prognosis. In conclusion, PR-ARF is still a critical occurrence, associated with serious prognosis for both women and kidneys. So far, the most effective measures remain the careful prevention and the aggressive management of the obstetric complications.

Acute renal failure in hypertensive disorders of pregnancy. Pregnancy outcome and remote prognosis in thirty-one consecutive cases

The purpose of this study is to report short-term pregnancy outcome, subsequent pregnancy outcome, and remote prognosis (follow-up from 0.3 to 9.8 years) in 31 cases complicated by acute renal failure. Eighteen patients had "pure" preeclampsia and 12 patients (13 pregnancies) had chronic hypertension, parenchymal renal disease, or both before pregnancy. All patients had serial evaluation of renal function, urine microscopy, and electrolyte studies at the onset of acute renal failure and on follow-up. There were three immediate maternal deaths (two in the pure preeclampsia group and one in the other group). Nine patients (50%) in the "pure" group required dialysis during hospitalization and all 18 patients had acute tubular necrosis. Five patients (42%) in the other group required immediate dialysis and three patients had bilateral cortical necrosis. The majority of pregnancies in both groups were complicated by abruptio placentae and hemorrhage. All 16 surviving patients in the pure preeclampsia group had normal renal function on long-term follow-up (average 4.0 +/- 3.1 years). Conversely, nine of the 11 surviving patients in the second group required long-term dialysis on follow-up and four of them ultimately died of end-stage renal disease. We conclude that proper management of acute renal failure in patients with pure preeclampsia-eclampsia does not result in residual function impairment.

Acute renal failure in pregnancy

Acute renal failure has become a very rare complication of pregnancy. This results from the virtual disappearance of septic abortion ARF and from the improvement of prenatal care, including the prevention of volume contraction which is mainly due to uterine haemorrhage, early diagnosis, and treatment of other classic maternal complications such as pre-eclampsia and acute pyelonephritis. The incidence of BRCN has also been declining during the last decade. Acute fatty liver, a potentially fatal disease, is often complicated by ARF. Early recognition of this disorder with prompt termination of pregnancy and intensive supportive therapy can reduce fetal and maternal mortality rate. The syndrome of idiopathic postpartum renal failure is also associated with a high morbidity and mortality. Beyond supportive treatment including haemo- or peritoneal dialysis, the use of potent antihypertensive drugs to control blood pressure and blood transfusion if necessary, specific therapy as plasma infusion, plasma exchange and antiplatelet drugs may be of value. Both peritoneal dialysis and haemodialysis may be used in gravidas with ARF. Early 'prophylactic' dialysis should be applied to pregnant women. Careful monitoring of fluid balance and anticoagulation is necessary during dialysis.

Severe preeclampsia with persistent oliguria: management of hemodynamic subsets

Nine patients with severe preeclampsia or eclampsia complicated by persistent oliguria failed to respond to fluid challenge and underwent pulmonary artery catheterization to guide further fluid and hemodynamic management. Three hemodynamic subsets of patients were defined. Patients in category I had low pulmonary capillary wedge pressure, hyperdynamic ventricular function, and moderate elevation of systemic vascular resistance. These patients responded to volume infusion with a decline in systemic vascular resistance, a rise in wedge pressure and cardiac output, resolution of oliguria, and no change in blood pressure. Patients in category II had normal or elevated pulmonary capillary wedge pressure and cardiac output and normal systemic vascular resistance; they responded to pharmacologic preload and/or afterload reduction. A single patient (category III) exhibited markedly elevated wedge pressure and systemic vascular resistance and depressed ventricular function. Oliguria in this patient responded to volume restriction and aggressive afterload reduction. Hemodynamic observations in patients in category II imply the presence of selective vasodilator responsive renal arteriospasm in some preeclamptic patients with oliguria.

Spectrum of acute cortical necrosis in Indian patients

Forty-nine out of 662 patients (7.4%) dialysed for acute renal failure were found to have bilateral renal cortical necrosis. Amongst 6061 autopsies carried out in our centre during the same period, the incidence of cortical necrosis was 0.7%. Obstetric causes were responsible for the renal lesion in 35 (71%) and non-obstetrical causes in 14 patients. In the obstetric group, cortical necrosis was observed in association with spontaneous or induced abortion in 39% and as a complication of late pregnancy in 33%. The non-obstetric causes included snake bite in 26 (12%), acute gastro-enteritis in 5 (10%), haemolytic uremic syndrome in 2 (4%) and G6PD deficiency with intravascular haemolysis in one patient (2%). Thirty-nine (80%) patients were anuric or severely oliguric throughout their illness but a steady rise in urinary output following a protracted phase of oligo-anuria was observed in ten patients. Forty-two (86%) patients died and seven survived. None of the survivors, however, achieved a normal renal function (Ccr 8 ml to 28 ml/min). The diagnosis of renal lesion was confirmed during life in 8 and after death in 41 patients. Morphological lesions were consistent with bilateral diffuse cortical necrosis in 39 (80%) and patchy lesions in 10 patients. Factors responsible for the high incidence of cortical necrosis amongst Indian patients have been high-lighted.

Clinicopathological spectrum of late postpartum renal failure; two contrasting cases

The clinical and renal biopsy findings from two patients in whom renal functional abnormalities developed in the late postpartum period are described. Both biopsies showed fibrin deposition in the renal vasculature, in one case marked and in the other mild. The patient with the more severely damaged kidney subsequently died, and the other is alive but with evidence of slowly progressing renal damage. The clinicopathological spectrum and pathogenesis of late postpartum renal failure are discussed.