Session: SAT 632-648-Pediatric Growth Case Reports
Poster Board SAT-646
Objective: The aim of the present study was to assess functional ability for ivTCF in children affected by different degrees of ALS insufficiency.
Subjects and Methods: Levels of IGF-I and ALS were assessed by RIA, IGFBP-3 by CLIA, ivTCF by size exclusion chromatography (Sephacryl S200) both before (TCF#) and after (TCF+) the addition of rhIGFBP-3 (6 µg/ml) and expressed as: (area under the curve/total area)x100. IGFALS gene was completely sequenced. Patients: 7 ALS-D, 7 HC-FDR, 15 prepuberal ISS and 5 prepuberal (PP) and 5 puberal (P) normal controls. ISS children were divided in 3 groups according to IGFALS genotype (HC for allelic variants of IGFALS gene or WT) and levels of IGF-I (normal or low, <-2.0 SDS): G1, HC with low IGF-I; G2, HC with normal IGF-I, and G3, WT with low IGF-I.
Results: One-way ANOVA (p<0.0001) showed lower TCF# in ALS-D (0.65±0.30%; mean±SD) compared to HC-FDR (6.42±3.54), G3 (4.99±2.87), PP (5.72±1.36) and P (9.99±1.80) (p<0.01). Besides G1 (3.15±1.71), G2 (3.61±0.86), G3 and PP were lower than P (p<0.05). TCF+ one-way ANOVA (p<0.0001) was low in ALS-D (2.29±1.14, p<0.001 vs. all others); G1 ISS (26.8±7.1) was significantly lower than G2 (48.4±4.6; p<0.001), G3 (45.9±11.9; p<0.01), and PP controls (43.5±2.6; p<0.05). There were no significant differences among G2, G3 and normal controls. TCF+ in G1 ISS was not different from HC-FDR (39.1±9.3).
Conclusions: Both TCF# and TCF+ allowed distinguishing complete ALS deficient patients from the rest. TCF# was higher in P vs. PP, but in TCF+ this difference disappeared. TCF+ in G1 ISS was significantly reduced when compared to the other ISS groups. These findings suggest that the limited ability shown by TCF+, a more ALS dependent parameter, in some IGFALS variants could contribute to the impairment of the IGF system observed in these subjects, leading to low IGF-I levels associated with some degree of growth deficit.
Nothing to Disclose: HMD, PAS, LK, ACK, ASM, DB, SVB, VP, IB, HGJ
*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm
See more of: Abstracts - Orals, Featured Poster Presentations, and Posters