New data supporting that early diagnosis and treatment are possible and necessary in intracellular cobalamin depletion: the case of transcobalamin II deficiency.
J Pediatr Endocrinol Metab
; 37(4): 380-386, 2024 Apr 25.
Article
en En
| MEDLINE
| ID: mdl-38436354
ABSTRACT
OBJECTIVES:
Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected. CASE PRESENTATION Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment.CONCLUSIONS:
This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
3_ND
Problema de salud:
3_diarrhea
Asunto principal:
Deficiencia de Vitamina B 12
/
Errores Innatos del Metabolismo de los Aminoácidos
/
Anemia Macrocítica
Límite:
Humans
/
Newborn
Idioma:
En
Revista:
J Pediatr Endocrinol Metab
Asunto de la revista:
ENDOCRINOLOGIA
/
PEDIATRIA
Año:
2024
Tipo del documento:
Article
País de afiliación:
Argentina