Identification of High-Risk Single Nucleotide Polymorphisms in the Human CYB5R3 Gene Responsible for Recessive Congenital Methemoglobinemia: A Computational Approach.

Introduction: NADH-cytochrome b5 reductase deficiency due to pathogenic variants in the CYB5R3 gene causes recessive congenital methemoglobinemia (RCM) type I or type II. In type I, cyanosis from birth is the only major symptom, and the enzyme deficiency is restricted only to erythrocytes. Whereas in type II, cyanosis is associated with severe neurological manifestations, and the enzyme deficiency is generalized to all tissues.

First Observation of HbM-Saskatoon at the Origin of Neonatal Cyanosis in a Tunisian Baby.

Several causes are known to be at the origin of neonatal cyanosis among them methemoglobinemia is by inheritance of an hemoglobin (Hb) M variant. This is a rare condition never been reported in Tunisia so far. Here, we report a Tunisian newborn with refractory cyanosis since birth.

Tunisian Newborn's Cord Blood: Reference Values of Complete Blood Count and Hemoglobin Fractions.

Objective: This study was aimed to establish local reference values for hematological indices and hemoglobin (Hb) fractions in umbilical cord blood (UCB) for the northern population of Tunisia.

Study Design: Our study included full-term newborns by vaginal deliveries. Hematological parameters were collected using an automated blood cell counter.