Macroamylasaemia and selective IgA deficiency

Macroamylasaemia and selective IgA deficiency were diagnosed in a 2 year old child who presented with persistent hyperamylasaemia. Macroamylasaemia is an isolated biochemical abnormality caused by aggregation of serum amylase activity with immunoglobulins. Early recognition of macroamylasaemia is important to avoid diagnosing pancreatic disease.

Redox and energetic state of red blood cells in G6PD deficiency, heterozygous beta-thalassemia and the combination of both

The levels of ATP, ADP, AMP, NADP, NADPH, NAD, NADH and reduced glutathione were determined in the red blood cells of individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, beta-thalassemia (beta-thal) heterozygotes and in a boy carrying both mutations. The results obtained confirmed a reduced concentration of NADPH in G6PD deficiency and showed that with the combination of both diseases, the red blood cell contained practically undetectable levels of NADPH. Assays of some red blood cell enzyme activities known to be markedly influenced by cell age suggested that a younger mean red cell population is present in beta-thal/G6PD deficiency. Thus, the marked oxidative stress caused by beta-thal, that is apparently incompatible with G6PD deficiency, in fact exists, probably because of the residual activity of this enzyme in the younger red cells.

[Zinc and chronic enteropathies]

In recent years the nutritional importance of zinc has been well established; its deficiency and its symptoms have also been recognized in humans. Furthermore, Acrodermatitis Enteropathica has been isolated, a rare but severe disease, of which skin lesions, chronic diarrhoea and recurring infections are the main symptoms. The disease is related to the malfunctioning of intestinal absorption of zinc and can be treated by administering pharmacological doses of zinc orally. Good dietary sources of zinc are meat, fish and, to a less extent, human milk. The amount of zinc absorbed in the small intestine is influenced by other nutrients: some compounds inhibit this process (dietary fiber, phytate) while others (picolinic acid, citric acid), referred to as Zn-binding ligands (ZnBL) facilitate it. Citric acid is thought to be the ligand which accounts for the high level of bioavailability of zinc in human milk. zinc absorption occurs throughout the small intestine, not only in the prossimal tract (duodenum and jejunum) but also in the distal tract (ileum). Diarrhoea is one of the clinical manifestations of zinc deficiency, thus many illnesses distinguished by chronic diarrhoea entail a bad absorption of zinc. In fact, in some cases of chronic enteropathies in infants, like coeliac disease and seldom cystic fibrosis, a deficiency of zinc has been isolated. Some of the symptoms of Crohn's disease, like retarded growth and hypogonadism, have been related to hypozinchemia which is present in this illness. Finally, it is possible that some of the dietary treatments frequently used for persistent post-enteritis diarrhoea (i.e. cow's milk exclusion, abuse and misuse of dietary fiber like carrot and carub powder, use of soy formula) can constitute a scarce supply of zinc and therefore could promote the persistency of diarrhoea itself.

Clinical heterogeneity in Sanfilippo disease (mucopolysaccharidosis III) type D: presentation of two new cases

Clinical, radiological and biochemical findings of two new cases of Sanfilippo disease, type D are reported. A high percentage of heparan sulfate was found in the urinary glycosaminoglycan pattern and a severe deficiency of N-acetylglucosamine-6-sulfate sulfatase was demonstrated in skin cultured fibroblasts from the patients. One of the patients presented mild intellectual impairment which differentiates him from the other cases described to date.

Trisomy 12p due to an adjacent 1 segregation of a maternal reciprocal translocation t(12;18) (p11;q23)

A 5, 9-12-year-old with trisomy 12 pdue to a maternal reciprocal translocation adjacent 1 segregation is presented. Comparison of his phenotype with that of other patients reported in the literature confirm the existence of a trisomy syndrome.

Partial trisomy 8q resulting from maternal translocation t(2;8)(q373;q23)

A patient with multiple congenital malformations due to partial 8q trisomy is reported. Karyotype-phenotype correlations suggest the possibility that partial trisomy 8q is a nosologically distinct syndrome.