Impaired muscle oxygen metabolism in uremic children: improved after renal transplantation.
BACKGROUND
The purpose of this study is to clarify skeletal muscle oxidative metabolism in children with end-stage renal disease (ESRD) before and after renal transplantation.


METHODS
We examined muscle oxygenation and metabolism by using noninvasive near-infrared spectroscopy in 10 patients (age, 12.4 +/- 3.1 years) 1 week before and 4 weeks after renal transplantation and in 10 controls (age, 12.8 +/- 2.6 years) during submaximal hand-grip exercise using the flexor digitorum superficialis muscle. We used 2 indicators to evaluate muscle metabolism. The rate of initial decrease in hemoglobin/myoglobin deoxygenation during arterial occlusion after exercise relative to the value at rest (S2/S1) was used as an indicator of mitochondrial oxygen consumption, whereas recovery time (TR) after exercise was used as an indicator of oxygen delivery to the muscle and aerobic capacity.


RESULTS
S2/S1 and TR after exercise were significantly lower in patients before renal transplantation compared with the control group (P < 0.05). S2/S1 and TR after exercise improved significantly after renal transplantation (P < 0.01, P < 0.05) and were not significantly different from those of controls.


CONCLUSIONS
Oxidative metabolism in skeletal muscle during exercise is impaired in children with ESRD and recovers after renal transplantation.
Matsumoto
Naoko
N
Department of Pediatric Nephrology, Tokyo Women's Medical University, Japan. naoko_pine@msn.com
Ichimura
Shiro
S
Hamaoka
Takafumi
T
Osada
Takuya
T
Hattori
Motoshi
M
Miyakawa
Sanpei
S
D000293:Adolescent; D002648:Child; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000378:metabolism* / Q000601:surgery*; D016030:Kidney Transplantation; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D019265:Spectroscopy, Near-Infrared; D016896:Treatment Outcome; D014511:Uremia / Q000209:etiology
D010100:Oxygen