Urine chromatography in skin diseases

Background. To assess excreted substances, the method of urine chromatography is used - a standard urine screening for hereditary metabolic diseases, which has been part of the arsenal of the medical genetic service since the end of the last century. The detected changes in the levels of excreted substances relative to the norm make it possible to modify the diet of patients with collagenopathies. Objective. Evaluation of the changes in the content of excreted substances in patients aged 1 to 5 years with a diagnosis of undifferentiated connective tissue dysplasia (UCTD) using the urine chromatography. Methods. The analysis of urine screening (excretion of amino acids) of 20 patients in the age range from 1 to 5 years with a diagnosis of UCTD was carried out. To detect excreted metabolites, the screening consisted of 15 qualitative and semi-quantitative tests, chromatography of 12 amino acids and 6 sugars, and electrophoresis of 4 glycosaminoglycans (GAGs). Results. An increase in the urine GAG level was found in 7 examined children. In 5 cases, an increase in the content of glucuronic acid was noted. All 20 patients had hyperaminoaciduria. An additional examination for the blood content of vitamins D and B6 showed that 2 patients had vitamin B deficiency and all 20 patients - vitamin D deficiency. There were 9 cases of cystine hyperexcretion, of which 7 cases showed an increase in urine GAG excretion. 4 patients with histidine hyperexcretion were identified. The study noted 9 cases of lysine hyperexcretion, of which 4 were associated with an increase in histidine content. It was noted that 7 patients with high GAG levels and the presence of hydroxyproline in the urine had more pronounced clinical symptoms; in 5 patients with normal hydroxyproline levels and increased GAG, the symptoms were less pronounced. Furthermore,in addition to skin changes, three patients in this group had frequent infections. Conclusion. Thus, using the method of urine chromatography, all 20 patients in the age range from 1 to 5 years with a diagnosis of UCTD were found to have changes in the content of excreted substances in the urine.

metabolic disorders, urine chromatography, undifferentiated connective tissue dysplasia