Physical function, muscle strength and muscle mass in children on peritoneal dialysis

Area of Science:

• Pediatric Nephrology
• Muscle Physiology
• Medical Imaging

Background:

• Peritoneal dialysis (PD) is a vital treatment for pediatric kidney failure.
• Children undergoing PD often experience impaired physical function and muscle weakness.
• The underlying mechanisms, particularly muscle structural changes, require further investigation.

Purpose of the Study:

• To evaluate physical function and muscle strength in children on PD.
• To determine if muscle structure alterations correlate with physical performance and strength deficits.
• To explore the role of muscle fat infiltration in PD-related functional decline.

Main Methods:

• Comparative study involving 22 children on PD and 16 healthy controls.
• Assessment of physical function using the 6-minute walk distance and gait speed tests.
• Measurement of quadriceps muscle strength (QMS) via hand-held dynamometry.
• Magnetic resonance imaging (MRI) to quantify quadriceps muscle cross-sectional area (CSA) and T2 signal intensity.

Main Results:

• Children on PD demonstrated significantly poorer performance on functional tests compared to controls.
• Quadriceps muscle strength (QMS) was notably lower in the PD group.
• While muscle CSA/BMI did not differ, T2 signal intensity was significantly elevated in PD patients, suggesting increased intramuscular fat.
• Both physical functioning and QMS were strongly associated with muscle CSA/BMI and T2 signal intensity.

Conclusions:

• Children on PD exhibit diminished physical function and muscle strength.
• Elevated T2 signal intensity in quadriceps muscle, indicative of increased fat infiltration, is a significant finding in PD patients.
• Increased intramuscular fat is a potential contributing factor to the observed physical and strength impairments in pediatric PD patients, alongside other known mechanisms.