TY - JOUR
T1 - Alpha-2-macroglobulin and albumin are useful serum proteins to detect subclinical peritonitis in the rat
AU - van Westrhenen, Roos
AU - Westra, Wytske M.
AU - van den Born, Jacob
AU - Krediet, Raymond T.
AU - Keuning, Eelco D.
AU - Hiralall, Johan
AU - Dragt, Cindy
AU - Hekking, Liesbeth H. P.
PY - 2006
Y1 - 2006
N2 - BACKGROUND: In experimental peritoneal dialysis (PD) studies, the occurrence of peritonitis is a confounder in the interpretation of effects of chronic peritoneal exposure to dialysis solutions. Since fluid cannot be drained in most experimental PD models in the rat, it is impossible to diagnose peritonitis based on dialysate white blood cell counts. To study the value of serum markers for the presence of peritonitis, alpha-2-macroglobulin (alpha2M) and albumin were measured in rats with and without peritonitis after chronic exposure to dialysis solutions. To further investigate the time course of these markers in relation to the severity of peritonitis, nondialyzed rats were challenged with increasing numbers of bacteria and followed for 28 days. METHODS: In the first study, alpha2M and albumin were measured in rats exposed to glucose/lactate-based dialysis fluid before sacrifice. A comparison was made between animals with peritonitis, as judged from the presence of extensive infiltrates after sacrifice (gold standard) and/or clinical signs of peritonitis, or absence of peritonitis and infiltrates. In the second study, rats were intraperitoneally (IP) injected with 3 different concentrations of Staphylococcus aureus, and serum alpha2M and albumin were measured at various time points. RESULTS: In the first study, serum alpha2M was higher and serum albumin was lower in animals with peritonitis compared to animals without peritonitis (both p < 0.05). In the second study, induction of alpha2M was clearly dependent on the inoculum concentration. Peak values of alpha2M were found at days 1 and 3. At all time points after inoculation, alpha2M was higher in all injected groups compared to the control group. Serum albumin values decreased in the highest inoculum group and remained decreased until 28 days after IP injection. Despite a low sensitivity, serum alpha2M > 40 mg/L and albumin < 32 g/L had a specificity of 100% for peritonitis. CONCLUSIONS: Measurement of alpha2M and albumin once per month is an additional tool in the diagnosis of silent peritonitis in the chronic peritoneal exposure model in the rat. Levels of alpha2M > 40 mg/L and albumin < 32 g/L are strong indicators for peritonitis. However, normal values do not exclude infectious peritonitis
AB - BACKGROUND: In experimental peritoneal dialysis (PD) studies, the occurrence of peritonitis is a confounder in the interpretation of effects of chronic peritoneal exposure to dialysis solutions. Since fluid cannot be drained in most experimental PD models in the rat, it is impossible to diagnose peritonitis based on dialysate white blood cell counts. To study the value of serum markers for the presence of peritonitis, alpha-2-macroglobulin (alpha2M) and albumin were measured in rats with and without peritonitis after chronic exposure to dialysis solutions. To further investigate the time course of these markers in relation to the severity of peritonitis, nondialyzed rats were challenged with increasing numbers of bacteria and followed for 28 days. METHODS: In the first study, alpha2M and albumin were measured in rats exposed to glucose/lactate-based dialysis fluid before sacrifice. A comparison was made between animals with peritonitis, as judged from the presence of extensive infiltrates after sacrifice (gold standard) and/or clinical signs of peritonitis, or absence of peritonitis and infiltrates. In the second study, rats were intraperitoneally (IP) injected with 3 different concentrations of Staphylococcus aureus, and serum alpha2M and albumin were measured at various time points. RESULTS: In the first study, serum alpha2M was higher and serum albumin was lower in animals with peritonitis compared to animals without peritonitis (both p < 0.05). In the second study, induction of alpha2M was clearly dependent on the inoculum concentration. Peak values of alpha2M were found at days 1 and 3. At all time points after inoculation, alpha2M was higher in all injected groups compared to the control group. Serum albumin values decreased in the highest inoculum group and remained decreased until 28 days after IP injection. Despite a low sensitivity, serum alpha2M > 40 mg/L and albumin < 32 g/L had a specificity of 100% for peritonitis. CONCLUSIONS: Measurement of alpha2M and albumin once per month is an additional tool in the diagnosis of silent peritonitis in the chronic peritoneal exposure model in the rat. Levels of alpha2M > 40 mg/L and albumin < 32 g/L are strong indicators for peritonitis. However, normal values do not exclude infectious peritonitis
M3 - Article
C2 - 16538883
SN - 0896-8608
VL - 26
SP - 101
EP - 107
JO - Peritoneal Dialysis International
JF - Peritoneal Dialysis International
IS - 1
ER -