Current issue “Postępy Nauk Medycznych” has been prepared by pediatricians from Medical University of Silesia, Department of Pediatrics and Silesian Children’s Hospitals.

It includes clinical studies, inter alia, concerning one of the most common causes of hospitalization – rotavirus diarrhea and presenting differences in its clinical course according to the age of the patient (1).

While searching for the cause or maybe effects of intestinal permeability changes in children with inflammatory bowel disease behavior of zonulin, a marker which is involved in relaxation of the so-called „tight junction” in the intestinal mucosa, was examined. In the work titled “Evaluation of intestinal permeability on the basis of zonulin levels in children with IBD” authors from the Department of Pediatrics pointed out the possibility of using measurement of zonulin levels in the evaluation of disorders of the intestinal mucosa as a non-invasive biomarker of damage to the intestinal mucosa (2).

Lipid disorders in nephrotic syndrome are not fully recognized: attempted to be applied to the behavior of the concentration of carnitine, a substance involved in beta-oxidation of long-chain fatty acids in the acute phase of the disease and remission. The results are presented in the work “Carnitine concentration levels in the serum of children with nephrotic syndrome” (3).