Postpartum haemolytic uraemic syndrome: case report and brief review

Atypical hemolytic uremic syndrome in the setting of complement-amplifying conditions: case reports and a review of the evidence for treatment with eculizumab

Atypical hemolytic uremic syndrome (aHUS) is a rare, genetic, progressive, life-threatening form of thrombotic microangiopathy (TMA) predominantly caused by dysregulation of the alternative pathway of the complement system. Complement-amplifying conditions (CACs), including pregnancy complications [preeclampsia, HELLP (hemolysis, elevated liver enzymes, low platelet count) syndrome], malignant hypertension, autoimmune diseases, transplantation, and others, are associated with the onset of TMA in up to 69 % of cases of aHUS. CACs activate the alternative pathway of complement and may be comorbid with aHUS or may unmask a previously undiagnosed case. In this review, three case reports are presented illustrating the onset and diagnosis of aHUS in the setting of different CACs (pregnancy complications, malignant hypertension, renal transplantation). The report also reviews the evidence for a variety of CACs, including those mentioned above as well as infections and drug-induced TMA, and the overlap with aHUS. Finally, we introduce an algorithm for diagnosis and treatment of aHUS in the setting of CACs. If TMA persists despite initial management for the specific CAC, aHUS should be considered. The terminal complement inhibitor eculizumab should be initiated for all patients with confirmed diagnosis of aHUS, with or without a comorbid CAC.

Malignant nephrosclerosis during pregnancy and in the postpartum period (the uremic hemolytic syndrome)

Histologic, immunohistologic, and ultrastructural features are presented of two cases with malignant nephrosclerosis during pregnancy. Primary malignant nephrosclerosis emerges as a clinical entity which can be distinguished from toxemia of pregnancy in the midtrimester and post partum. The first description of malignant nephrosclerosis dates from 40 years ago, but only a few cases were reported associated with pregnancy. Although disseminated intravascular coagulation seems involved, the morphology is different from that of toxemia. Malignant nephrosclerosis reveals a close similarity to the hemolytic uremic syndrome. Early diagnosis by renal biopsy and proper treatment may prevent a lethal outcome due to progressive failure.

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.

Postpartum renal failure associated with eclampsia and penicillin hypersensitivity

A case of acute renal failure associated with disseminated intravascular coagulation occurring immediately post partum is reported. The aetiological role of the associated eclampsia together with evidence for a hypersensitivity reaction to ampicillin is discussed.