[Congenital hyperinsulinism--novel insights into etiology, diagnosis and treatment]. / Kongenitalni hiperinzulinizam- -novosti o nastanku, dijagnosticiranju i lijecenju bolesti.

Congenital hyperinsulinism (CHI) is a major cause of persistent hypoglycemia in the neonatal and early infancy periods. Althought the disease is relatively rare with incidence of about 1:25 000-50 000 live births, the importance of the disease should not be underestimated. Namely, prompt recognition and management of patients with CHI is essential, if permanent neurological impairment is to be avoided. CHI is caused by mutations in one of the 7 genes involved in the regulation of insulin secretion in pancreatic beta-cells. It is important to introduce specific medical therapy as soon as diagnosis is established. Severe, neonatal forms of CHI are often resistant to medications, thus they require surgical procedure. The preoperative genetic testing and scintigraphy are indicated to distinguish histological subtypes of the disease (focal vs. diffuse CHI). Patients with focal disease are usually cured after pancreatic resection, while diffuse disease has much worse prognosis. This manuscript offers novel insights into CHI and emphasizes the role of early diagnosis as crucial for succesful treatment that was recently enriched with novel options.

[Vitamin B12 deficiency in children--underestimated danger in the light of new knowledge]. / Manjak vitamina B12 u djece --podcijenjena opasnost u svjetlu novih spoznaja.

Vitamin B12 (cobalamin) has two active forms, adenosylcobalamin and methylcobalamin which have a key role in two important metabolic pathways in humans and their deficiency is responsible for clinical problems. Cobalamin is essential during whole life, but its sufficient amount is extra important in fetal and neonatal period, when it is essential for normal child growth and development as well as for normal development of the central nervous system. Because of very complex transport and metabolism, its deficiency can be manifested in numerous congenital and acquired disorders. Vitamin B12 deficiency mostly has non-specific clinical features, it carries a great risk of permanent consequences, but most frequently it is easily curable if diagnosed on time. In Croatia cobalamin deficiency in children has been diagnosed too rarely. Accordingly, the aim of this paper is to point to the recently gained knowledge on cobalamin metabolism, present typical case reports and to provide guidelines for rapid and proper diagnostic and therapeutic approach.

Changes of the corpus callosum in children who suffered perinatal injury of the periventricular crossroads of pathways.

There is a high incidence of periventricular leukomalacia, caused by hypoxia-ischemia, in preterm infants. These lesions damage the periventricular crossroads of commissural, projection and associative pathways, which are in a close topographical relationship with the lateral ventricles. We explored to what extent abnormalities of echogenicity of the periventricular crossroads correlate with changes in size of the corpus callosum. Our study included nine infants (gestation from 26-41 weeks; birth weight between 938-4450 grams) with perinatal brain injury. Periventricular areas, which topographically correspond to the frontal, main and occipital crossroad, were readily visualized by cranial ultrasound scans, performed during the first two weeks after birth. Corpus callosum mediosagittal area measurements were performed using magnetic resonance images, acquired between the first and sixth postnatal month (postmenstrual age 40-49 weeks). We found a statistically significant correlation between the increased echogenicity in the crossroad areas and the decrease of the corpus callosum midsagittal area (p < 0.05). This supports the hypothesis that callosal fibers can be damaged, during growth through the periventricular crossroads of pathways.