ESPN 51th Annual Meeting

ESPN 2018


 
Two cases with diverse course of aHUS related to Cobalamin C defect
MIHRIBAN İNÖZÜ 1 BORA GÜLHAN 1 AYŞEGÜL TOKATLI 2 TURGAY COŞKUN 2 REZAN TOPALOGLU 1

1- HACETTEPE UNIVERSITY FACULTY OF MEDICINE, DIVISION OF PEDIATRIC NEPHROLOGY, ANKARA, TURKEY
2- HACETTEPE UNIVERSITY FACULTY OF MEDICINE, DIVISION OF PEDIATRIC METABOLIC DISEASES, ANKARA, TURKEY
 
Introduction:

 Early-onset hemolytic uremic syndrome (HUS) has been shown to be associated with cobalamin C (cblC) defect which is the most common inborn errors of vitamin B12 metabolism. 

Material and methods:

 We report two patients who have mutations in MMACHC gene.

Results:

 The first patient was five months old girl, presented with hypertension, seizure, pallor and diarrhea. She was diagnosed as TMA with the presence of direct Coombs test negative hemolytic anemia, thrombocytopenia, renal function impairment, hypertension and proteinuria. Clinical findings of TMA, presence of consanguinity and positive family history, infantile age, megaloblastic changes on bone marrow, neurological signs and optic nerve atrophy yielded the diagnosis of cblC defect.The second patient was three months old boy, third child of nonconsanguineous mariage, presented with diarrhea and periorbital edema. Pallor and axial hypotonisity were observed. The clinical and laboratory findings showed evidence of HUS. Bone marrow aspiration revealed megaloblastic changes. On follow-up, hypertension and oliguria developed with an increase in serum creatinine level. Peritoneal dialysis was initiated.Metabolic evaluation of two patients were consistent with cblC defect. Methionine restricted diet, parenteral hydroxocobalamine, folinic acid, carnitine and betaine were initiated both of themOn follow-up, renal involvement completely improved, antihypertensive agents were stopped and there was no further seizure in patient 1. She gradually caught up with normal motor development appropriate for her age and she could follow the nearby objects and make an eye contact. Patient 2, serum creatinine levels decreased and blood smear findings dissolved but oliguria persisted and peritoneal dialysis continued. He died because of respiratory failure and cardiac arrest.

Conclusions:

 CblC defect should be ruled out in every possible case with aHUS. There is wide variation in the clinical presentation and severity of cblC defect. Improvement of outcome in these patients probably requires very early diagnosis and prompt therapy.