Acute poststreptococcal glomerulonephritis (APSGN) is the most common form of postinfectious nephritis worldwide. The relationship between inflammation and arterial stiffness has been described elsewhere, but there have been no studies that have analyzed the association between arterial compliance and APSGN. The aim of this study is to assess brachial-ankle pulse wave velocity (baPWV) in pediatric patients with APSGN, and the value of baPWV in predicting the outcome. We evaluated 16 children diagnosed with APSGN, 11 children with acute pyelonephritis (APN), and 25 healthy individuals in our hospital. The baPWV of all candidates was measured. In addition, follow-up of the APSGN group was conducted for baPWV, blood pressure and biochemical parameters. Significantly increased baPWV was observed in the APSGN group at initial diagnosis (P<0.001), in comparison with the APN group and healthy controls. Of these, 13 patients received sequential measurement of baPWV. Overwhelmingly, baPWV was rapidly normalized in 11 patients, whereas 2 boys presented with persistently higher baPWV. During the follow-up period of 2-3 years, both had consistency of proteinuria, and consequently, they progressed to either chronic renal insufficiency or end-stage renal disease (ESRD). In conclusion, the results demonstrate that APSGN involves not only the kidney, but also the arteries outside the kidney. Acute arterial stiffness might persist in patients who do not recover, but develop chronic kidney disease (CKD).