High performance liquid chromatography evaluation of serum carbohydrate-deficient transferrin and more sialylated transferrin glycoforms in children.

ABSTRACT

OBJECTIVES: The evaluation of the age-specific distribution of transferrin glycoforms in paediatric patients may help in defining reference intervals which are critical for an improved and earlier diagnosis. DESIGN AND METHODS: Serum samples from 224 children (age 2 months-14 years) were analyzed by HPLC (Bio-Rad CDT/HPLC kit) and glycoforms expressed as percentage of the total area of transferrin (Tf). RESULTS: Asialo- and Monosialo-Tf were not detectable in any patient. Medians (IQR) were respectively 0.92% (0.80-1.04%) for Disialo-Tf; 3.47% (2.69-4.18%) for Trisialo-Tf; 82.54% (81.32-83.53%) for Tetrasialo-Tf; 12.73% (11.91-14.09%) for Pentasialo-Tf. Statistically significant differences in Trisialo-Tf (p < 0.0005), Tetrasialo-Tf (p = 0.001), Pentasialo-Tf (p < 0.0005), but not in Disialo-Tf, were observed between the age groups. CONCLUSIONS: Age-specific Disialo-Tf cut-offs are not necessary. In children 1.3% and 6.4% may be suggested as upper limits of normal range to detect increases of Disialo- and Trisialo-Tf. The presence of Asialo- and Monosialo-Tf should be considered an abnormal finding and prompt further investigations.