Glucose-6-phosphate dehydrogenase deficiency in newborns

In our lives, many newborns will show symptoms of trace element deficiency when they are just born. At this time, mothers will choose to check their children. Some children are diagnosed with glucose-6-phosphate dehydrogenase deficiency. This deficiency is a hereditary hemolytic disease with a very high incidence rate. It is most likely to cause anemia in children. So how should newborns with glucose-6-phosphate dehydrogenase deficiency be treated?

It is a group of hereditary hemolytic diseases caused by a significant deficiency of erythrocyte glucose-6-phosphate dehydrogenase (G-6-PD). Some cases develop the disease after eating broad beans, commonly known as favism. About 200 million people worldwide suffer from this disease. my country is one of the high-incidence areas of this disease, with a distribution pattern of higher in the south and lower in the north, and the prevalence rate is 0.2% to 44.8%. It is mainly distributed in provinces south of the Yangtze River, with high incidence in Hainan, Guangdong, Guangxi, Yunnan, Guizhou, Sichuan and other provinces. The cause of G-6-PD deficiency is a mutation in the G-6-PD gene, which leads to reduced activity of the enzyme. Red blood cells cannot resist oxidative damage and are destroyed, causing hemolytic anemia.

Causes

The incidence of favism is quite complicated. For example, favism only occurs in people with G-6-PD deficiency, but not all people with G-6-PD deficiency will experience hemolysis after eating broad beans; people who have had favism eat broad beans every year, but they may not develop the disease every year; the degree of hemolysis and anemia in the patients is not parallel to the amount of broad beans eaten; the incidence rate in adults is significantly lower than that in children.

G-6-PD deficiency is an X-linked incomplete dominant inheritance, with males more likely to develop the disease than females. Usually, the characteristic of dominant inheritance is that the disease-causing gene of either parent can cause the disease as long as it is passed on to the children. Some individuals carrying dominant genetic genes may have no clinical symptoms, that is, the penetrance is not 100%. This situation is called incomplete dominance. That is, one of the parents may be a carrier of a dominant gene but have no clinical manifestations, just like G-6-PD deficiency. Because it is X-linked, incomplete penetrance occurs in the population, which is called X-linked incomplete dominant inheritance. Another possibility is gene mutation, but the probability of this is extremely small.

Clinical manifestations

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is one of the most common types of hemolytic anemia caused by red blood cell enzyme deficiency. Most patients with red blood cell G-6-PD deficiency have no clinical symptoms. Patients with hemolysis have similar clinical manifestations to those with general hemolytic diseases, mainly acute onset, anemia, jaundice, hemoglobinuria, and clear causes can be found in the medical history.

Clinically, it can be divided into five types: congenital non-spherocytic hemolytic anemia type I, favism, drug-induced or infection-induced hemolytic anemia, and neonatal jaundice. If there is G-6-PD deficiency without anemia, it is called erythrocyte G-6-PD deficiency.

1. Congenital non-spherocytic hemolytic anemia (CN-SHA)

The disease usually develops in infancy and childhood, and about half of cases present with hyperbilirubinemia in the neonatal period. In severe cases, chronic hemolysis may occur without any inducement, with three main characteristics: jaundice, anemia, and splenomegaly. In mild cases, anemia is usually mild, with no obvious jaundice or splenomegaly, and hemolytic crisis occurs when infection or drug-induced hemolysis occurs. There is an increase in macrocytosis, anisocytosis and dysmorphism of red blood cells, with occasional alkaliphilic stippling.