Eculizumab in neonatal hemolytic uremic syndrome with homozygous factor H deficiency.

BACKGROUND: Neonatal atypical hemolytic uremic syndrome (aHUS) is a rare but severe disease that is mainly due to methylmalonic aciduria or genetic complement abnormalities. Traditional management of aHUS includes plasma infusion/exchange, but in small or unstable infants, plasma exchange can be challenging because of high extracorporeal volume and difficulty to obtain an adequate venous access. The C5 complement blocker eculizumab has become a cornerstone of first-line management of aHUS due to complement deregulation in older patients. However, little data are available on its use in neonatal aHUS. CASE-DIAGNOSIS/TREATMENT: We report on an 11-day-old neonate with severe aHUS (myocardial impairment, respiratory failure, acute kidney disease requiring hemodiafiltration) due to homozygous factor-H deficiency. She received early treatment with eculizumab as first-line therapy and completely recovered within 5 days. A second dose of eculizumab was administered 7 days after the first infusion, followed by a dose every 2 weeks for 2 months and then every 3 weeks, at the same dosage (300 mg). With more than 24 months of follow-up, renal function remains normal. CONCLUSIONS: We report on the long-term efficacy and safety of eculizumab as first-line therapy in neonatal aHUS. However its use still requires optimization in terms of indications and administration (frequency, dosage).

Thrombocytopenia is not mandatory to diagnose haemolytic and uremic syndrome.

BACKGROUND: Hemolytic and uremic syndrome (HUS) diagnosis involves association of non immune hemolytic anemia, thrombocytopenia, and renal failure. HUS without thrombocytopenia has been observed, we call it partial HUS. Its real frequency and outcome are unknown. The aim of this study was to determine the prevalence of patients with normal platelets count in two HUS cohorts and to compare their outcome to patients with thrombocytopenia. METHODS: We retrospectively identified HUS diagnosis in two different cohorts. The first cohort was from a single center and consisted of all cases of HUS whatever the aetiology, the second was multicentric and consisted of atypical HUS patients. These cohorts were divided into two groups depending on the presence or absence of thrombocytopenia. Clinical and biological data were compared between thrombopenic and non thrombopenic group. RESULTS: We identified 13% (20/150) of patients with normal platelets count: 10 episodes (18%) of HUS in six patients (14%) in the monocentric cohort and 14 patients (13%) with 17 episodes (12%) in the multicentric cohort of atypical HUS. Groups differed in platelets count and LDH level. In both cohorts, renal outcome was similar to patient presenting with thrombocytopenia. CONCLUSION: HUS with normal platelets count is not infrequent. Relative to classical clinical presentation of HUS, partial HUS has similar characteristics and identical poor renal outcome and so must be treated in the same way.