A convenient diagnostic function test of peripheral blood neutrophils in glycogen storage disease type Ib.

Neutrophils from patients suffering from glycogen storage disease type Ib (GSD-Ib) show several defects. one of which is a decreased rate of glucose utilization. In this study, we established experimental conditions to show the stimulation of the neutrophil respiratory burst by extracellular glucose. With phorbol-myristate-acetate as stimulus of the burst, the activity of the NADPH oxidase in GSD-Ib neutrophils hardly increased on addition of glucose. In control and GSD-type Ia neutrophils, a clear increase was observed. The lack of response to extracellular glucose in GSD-Ib neutrophils is correlated with the inability to raise intracellular glucose-6-P levels on glucose addition, thereby limiting the activity of the generation of NADPH in the hexose-monophosphate shunt. Our study shows the usefulness of this test for the diagnosis of neutrophil function abnormality in GSD-Ib patients.

Pancreatic glucagon levels in infants and children with hyperinsulinemia.

Serum concentrations of pancreatic glucagon were measured in 40 patients with hyperinsulinemic hypoglycemia. In infants with severe disease the glucagon levels were markedly elevated; lower levels were observed in children with episodic hypoglycemia. During diazoxide treatment and after pancreatectomy, the glucagon levels decreased proportionally to suppression of the insulin secretion. Thus the secretion of glucagon seems to be retained in hyperinsulinism in proportion to the insulin hypersecretion, and an increased glucagon level indicates long during and severity of hyperinsulinemic hypoglycemia.

A case of vitamin B12--independent methylmalonic aciduria.

The reported case was a female infant aged 7 months with severe ketoacidosis associated with vomiting, dehydration and cardiorespiratory disturbances at the time of exacerbation of the disease. The analysis of urinary organic acids by the GC-MS method revealed methylmalonic aciduria. After placing the infant on a low-protein diet (1.5 g of protein per 1 kg of body weight) and initially vitamin B12 parenterally a striking clinical improvement with evident progress in psychomotor development of the child was achieved.

Congenital lactic acidosis in children--differential diagnosis in 44 cases.

The purpose of the study was differential diagnosis of lactic acidosis in 44 children aged from 2 weeks to 4 years. In all of them the lactate level in repeated determinations exceeded 27 mg/100 ml. From the point of view of clinical manifestations the children were divided into three groups: 26 with hepatomegaly and hypoglycaemia (I), 6 with ataxia and retardation of somatic development (II), 12 with mental retardation and muscular hypotonia (III). Together with basic biochemical studies other tests were done, if necessary, including glucose and alanine loading, lactate determination in cerebrospinal fluid, analysis of urinary organic acids by the GC-MS method, morphological examinations of muscle biopsy material, enzymatic determinations in liver biopsy material. In group I glycogenosis was suspected and its type was finally established after biochemical and enzymatic tests (types I, Ib, III, VI, VIa, XI). In one case fructose-1,6-diphosphatase deficiency was suspected. In group II the clinical manifestations resembled Leigh's syndrome. The tests demonstrated an inhibition of glucose formation from alanine, and lactate level in the cerebrospinal fluid was evidently raised above that in the serum. Gasometric index showed the presence of respiratory alkalosis with metabolic compensation rather than primary lactate acidosis. In group III, with considerable clinical variety of signs, in only nine out of 12 children the cause of lactate acidosis could have been established (pathological changes of mitochondria in 4 cases, secondary increase of lactate without pathogenetic importance in 4, and 3-hydroxy-3-methylglutaric acidosis in 1 case. In conclusion it is thought that this combination of diagnostic methods is useful in differential diagnosis of congenital lactate acidosis in children.

The surgical approach to hyperinsulinism and hypoglycemia in children.

Authors present 19 children aged from 2 weeks to 16 y with severe hypoglycemia. In 3 oldest children a single nesidioma was found. In other 16 children mainly infants nesidioblastosis has been recognised, and in those cases the subtotal pancreatectomy was performed. In 4 infants the additional resection of the pancreas was done because after the primary procedure hypoglycemia persisted. All patients survived and were euglycemic. Severe hypoglycemia leads to brain damage and therefore should be treated as an urgent state.