Middle molecules in peritoneal equilibration test as a marker of peritoneal stress in children on continuous peritoneal dialysis.
At 1 month, 3 months, 6 months, and more than 6 months after healed peritonitis, we evaluated repeated peritoneal equilibration tests (PETs) for small molecules such as urea, and middle molecules such as cystatin C, beta 2-microglobulin, and alpha 1-microglobulin. We analyzed a total of 104 PETs in 21 children aged 1.7-18.6 years (median: 9.9 years). Equilibration quotients (D/P)--that is, substrate concentration in dialysis fluid (D) divided by substrate concentration in plasma (P)--were calculated after a dwell time of 4 hours. The D/P for urea did not change after healed peritonitis. In a cross-sectional study, the D/P for middle molecules showed an increase in peritoneal permeability between 3 months and 6 months after a healed peritonitis. In a consecutive follow-up of 4 patients for more than 6 months, beta 2-microglobulin and, more impressively, alpha 1-microglobulin showed a statistically significant increase in D/P (p < 0.05) 3 months after a healed peritonitis. All differences seen were completely reversible after more than 6 months, showing that peritoneal function is rather stable if peritonitis is healed. It is noteworthy that peritoneal dysfunction lasts for up to 6 months after a completely healed peritonitis. This period might be a vulnerable phase in continuation of peritoneal dialysis.
Laux
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C
Department of Pediatric Nephrology, Universitäts-kinderklinik Essen, Germany.
Weiss
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B
Bonzel
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KE
D000293:Adolescent; D000510:Alpha-Globulins / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D015891:Cystatins / Q000032:analysis*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010531:Peritoneal Dialysis, Continuous Ambulatory; D010537:Peritoneum / Q000502:physiology*; D010539:Permeability; D014508:Urea / Q000032:analysis; D001613:beta 2-Microglobulin / Q000032:analysis*
D000510:Alpha-Globulins; D015891:Cystatins; C016001:alpha-1-microglobulin; D001613:beta 2-Microglobulin; D014508:Urea