Acute renal failure in a patient with paroxysmal cold hemoglobinuria

Hemolysis-associated hemoglobin cast nephropathy results from a range of clinicopathologic disorders

Intravascular hemolysis is relatively rare but can lead to acute kidney injury (AKI), from increased destruction of erythrocytes and release of free hemoglobin. Since hemolysis and hemoglobinuria are known causes of acute kidney injury we sought to define clinicopathologic findings and outcomes of patients with hemolysis-associated hemoglobin cast nephropathy through a retrospective analysis of 27 cases. The mean patient age was 47 years (range 19-79) and the female-to-male ratio was 1.3:1. All patients presented with AKI with a mean serum creatinine of 8.0 (range 2.9-17.0) mg/dL. Etiologies included autoimmune hemolytic anemia (30%), medication (26%), paroxysmal nocturnal hemoglobinuria (7%), procedural/mechanical causes (7%), transfusion of incompatible blood (4%), toxin ingestion (4%), disseminated intravascular coagulation (4%), and hemoglobinopathy (4%). All biopsies showed acute tubular injury and pigmented, proteinaceous casts characterized by positive hemoglobin immunohistochemistry. After a mean follow-up of nine months (range 0.5-26), the mean serum creatinine was 1.3 (range 0.6-3.3) mg/dL, with 78% of patients returning to normal kidney function. Thus, based on our clinicopathologic case series, hemolysis-associated hemoglobin cast nephropathy is an important entity for clinicians and pathologists to recognize as treatment hinges upon elimination of the pathogenic driver of intravascular hemolysis.

Diagnostic difficulties in a patient with paroxysmal cold haemoglobinuria and acute kidney injury

Paroxysmal cold haemoglobinuria (PCH) is a form of autoimmune haemolytic anaemia (AIHA) characterised by a sudden onset of haemoglobinuria, either spontaneously or following exposure to cold. In children, it is commonly seen following a viral illness or after immunisation. Diagnosis of PCH is confirmed by a positive Donath Landsteiner (DL) test in which biphasic haemolysins are detected. However, in a real clinical setting, the serological diagnosis of PCH is not always easy. PCH can cause tubular renal injury, which in turn can lead to renal impairment. We describe a case of a two-year-old boy who was admitted to the hospital with pallor, jaundice, dehydration, and dark urine. Two weeks before admission, the child had an upper respiratory tract infection. Laboratory tests showed severe anaemia (haemoglobin 4.5g/dl, haematocrit 11.5%, LDH 8525 U/l), hyperbilirubinaemia (104 μmol/l), haemoglobinuria, and acute kidney injury: GFR 43.9 ml/min/1.73 m² (grade 2 according to Acute Kidney Injury Network). The direct antiglobulin test was positive for C3c and C3d complement components. The diagnosis of PCH was confirmed by the presence of biphasic antibodies in a DL test on the third day of hospitalisation. The patient received supportive treatment.

Paroxysmal cold haemoglobinuria leading to acute renal failure: A case report

Paroxysmal cold haemoglobinuria (PCH) is a form of autoimmune haemolytic anaemia (AIHA) characterised by sudden onset of haemoglobinuria either spontaneously or following exposure to cold. It was previously believed to be a rare form of AIHA, but is now thought to be responsible for up to 40% of cases of acute transient haemolytic anaemia in children1 following viral infections. Although the anaemia can be severe, illness is characteristically of short duration and does not recur. Published reports of PCH in children leading to renal impairment are rare, with supportive management only being used in affected cases.2, 3 We describe the case of a 2-year-old boy who developed acute renal failure (ARF) secondary to PCH, requiring peritoneal dialysis, where the early institution of plasma exchange was associated with rapid recovery of renal function.