Suwanboriboon W.Chaiyapuk T.Tinnabut I.Sanpawitayakul G.Srisawat C.Junnu S.Liammongkolkul S.Chotipanang K.Rukprayoon H.Laohathai P.Densupsoontorn N.Mahidol University2025-07-012025-07-012025-01-01Pediatric Nephrology (2025)0931041Xhttps://repository.li.mahidol.ac.th/handle/20.500.14594/111021Background: Patients with chronic kidney disease (CKD) stage 5D receiving peritoneal dialysis (PD) are at risk for thiamin deficiency (TD). This study compared the proportion of TD in pediatric CKD patients undergoing PD with that in healthy controls and evaluated the associations of various factors with TD in CKD patients. Methods: Thirty-two patients with CKD stage 5D and 34 healthy children were recruited. The participants reported their consumption of foods containing antithiamin factors and completed a 3-day food record to assess their intake of thiamin, energy, and macronutrients. The medical records of the CKD group were reviewed. Thiamin status was assessed via an erythrocyte transketolase activity assay, where the thiamin pyrophosphate effect was determined. Results: Thirteen percent of participants in the CKD group had TD, whereas 29% of the healthy controls did (p = 0.093). The CKD group had significantly greater total thiamin intake per 1,000 kcal of energy due to thiamin supplementation (2.14 [1.83, 2.99] vs. 0.87 [0.59, 1.14] mg/1,000 kcal; p < 0.001), despite inadequate dietary thiamin intake. A longer PD duration (in months) and a high-transport peritoneal membrane status were significantly associated with poorer thiamin status (β = + 0.59, p < 0.001, and β = + 0.38, p = 0.013, respectively). In contrast, greater total thiamin intake was correlated with improved thiamin status (β = -0.35, p = 0.022). Conclusions: Thiamin deficiency was observed in 13% of pediatric CKD patients on PD and 29% of healthy controls. In CKD patients, TD was associated with longer PD duration (in months), high-transport peritoneal membrane status, and low total thiamin intake.MedicineArticleSCOPUS10.1007/s00467-025-06847-62-s2.0-1050087590351432198X