Cobalamin c deficiency associated with antifactor h antibody-associated hemolytic uremic syndrome in a young adult.

BACKGROUND: Thrombotic microangiopathy (TMA) syndromes are characterized by the association of hemolytic anemia, thrombocytopenia and organ injury due to arteriolar and capillary thrombosis. CASE PRESENTATION: We report the first case of adult onset cobalamin C (Cbl C) disease associated with anti-factor H antibody-associated hemolytic uremic syndrome (HUS). A 19-year-old woman was admitted to the nephrology department owing to acute kidney failure, proteinuria, and hemolytic anemia with schizocytes. TMA was diagnosed and plasma exchanges were started in emergency. Exhaustive analyses showed 1) circulating anti factor H antibody and 2) hyperhomocysteinemia, hypomethioninemia and high levels of methylmalonic aciduria pointing towards Clb C disease. Cbl C disease has been confirmed by methylmalonic aciduria and homocystinuria type C protein gene sequencing revealing two heterozygous pathogenic variants. The kidney biopsy showed 1) intraglomerular and intravascular thrombi 2) noticeable thickening of the capillary wall with a duplication aspect of the glomerular basement membrane and a glomerular capillary wall IgM associated with Cbl C disease related TMA. We initiated treatment including hydroxycobalamin, folinic acid, betaine and levocarnitine and Eculizumab. Rituximab infusions were performed allowing a high decrease in anti-factor H antibody rate. Six month after the disease onset, Eculizumab was weaning and vitaminotherapy continued. Outcome was favorable with a dramatic improvement in kidney function. CONCLUSION: TMA with renal involvement can have a complex combination of risk factors including anti-FH autoantibody in the presence of cblC deficiency.

Chronic renal failure complications and management in kidney transplanted and nontransplanted patients.

BACKGROUND: Our purpose was to compare the management of chronic kidney disease (CKD) according to Kidney Disease Quality Initiative (K/DOQI) recommendations in kidney transplanted patients (T) and nontransplanted ones (NT). METHODS: Data concerning CKD complications were collected retrospectively. Patients seen in consultations in our department from May 2009 to June 2010 were selected if they had at least 6 months of follow-up, CKD stage 4 or 5, and no exclusion criteria namely hospitalization, active cancer, or infection in the 3 months before data collection. RESULTS: Fifty-eight T were compared with 85 NT matched by CKD stage (4-5). Anemia within K/DOQI target was better controlled among NT (51.2% versus 41.3%); however, ferritin levels within K/DOQI target were higher (80% T versus 51.7% NT). Average arterial blood pressure was similar in both groups but 51.7% of T were in K/DOQI target versus 41% of NT. Dyslipidemia within cholesterol K/DOQI target was better controlled in 60% (NT) versus 35% NT with 63.5% versus 38% NT within low-density lipoprotein K/DOQI targets. Phosphorus level was better controlled among T; parathyroid was better controlled in among 65% NT versus 50% T within the target level. CONCLUSION: Most complications of CKD were better managed among NT.