Creatine-kinase and pyruvate-kinase activities in normal children: implications in Duchenne muscular dystrophy...

Area of Science:

• Biochemistry
• Pediatrics
• Clinical Chemistry

Background:

• Serum creatine-kinase (CK) and pyruvate-kinase (PK) are key enzymes with diagnostic relevance.
• Understanding age- and sex-specific enzyme levels is crucial for pediatric diagnostics.
• Previous studies have not comprehensively analyzed CK and PK in a large pediatric cohort.

Purpose of the Study:

• To establish reference values for serum CK and PK in children under 15.
• To investigate correlations between enzyme activity, sex, and age in this population.
• To provide guidance for interpreting enzyme levels in pediatric patients, particularly those at risk for muscular dystrophy.

Main Methods:

• Serum samples were collected from 201 boys and girls aged under 15.
• Enzyme activities for CK and PK were measured using standard biochemical assays.
• Statistical analyses were performed to compare enzyme levels across age groups and sexes and to assess correlations.

Main Results:

• Mean CK activity was significantly higher in boys than in girls across all ages.
• CK activity showed a slight but significant correlation with age only in females.
• Mean PK activity was higher in children than adult women and decreased significantly with age in both sexes.
• A slight correlation between CK and PK was observed exclusively in girls.

Conclusions:

• Pediatric reference ranges for CK and PK vary by sex and age.
• CK and PK levels in females at risk for Duchenne muscular dystrophy should be interpreted relative to age- and sex-matched controls.
• These findings aid in the accurate diagnosis and monitoring of pediatric neuromuscular conditions.