PurposeWe investigated the relationship between blood pressure (BP) and the activity of lysosomal exoglycosidases: N-acetyl-β-hexosaminidase (HEX), its isoenzymes A (HEX A) and B (HEX B), α-fucosidase (FUC), β-galactosidase (GAL), β-glucuronidase (GLU) and α-mannosidase (MAN) in pre-hypertensive (high normal blood pressure - HNBP) and normal blood pressure (NBP) children. Material and methodsThe study was carried out with urine samples collected from 176 children, aged 6–17.9 years, divided into 2 groups: 42 HNBP and 134 NBP subjects. The children were stratified depending on systolic and diastolic BP (SBP; DBP): HNBP (SBP and/or DBP greater than or equal to the 90th percentile, but less than the 95th percentile) for sex, age, and height; and NBP (SBP and DBP less than the 90th centile). The activities of lysosomal exoglycosidases were determined by the colorimetric method, and expressed in pKat/mL and pKat/μgCr. ResultsThe activity of urinary HEX A in HNBP group was significantly higher than in NBP (p < 0.05). The HNBP group showed significant positive correlation between HEX, HEX A (pKat/mL) and SBP. AUC for HEX A was 0.616, cut-off value −29.351 pKat/mL (sensitivity 51.2%, specificity 71.8%), and 0.589, cut-off value −0.054 pKat/μgCr (sensitivity 31.7%, specificity 86.3%). ConclusionsThis is the first report of the relationship between BP and the activity of urinary lysosomal exoglycosidases: HEX, HEX A and HEX B, FUC, GAL, GLU, and MAN in healthy children and adolescents. It seems that HEX A (pKat/mL) can be used as a useful tool in identifying children with HNBP.