Endocrine Abstracts

Glycogen storage diseases (GSD) are autosomal recessive inborn errors of carbohydrate metabolism. With current dietary therapy, life expectancy in patients with GSD has improved considerably and almost all children reach adulthood. Notwithstanding intensive therapy, patients with GSD have an increased risk of osteoporosis. We followed 20 patients aged 22–62 (mean age of 37) years with GSD type I, III and IX, for up to 5 years with serial measurements of bone turnover markers and Bone mineral density (BMD). BMD was measured by dual-energy X-ray absorptiometry (DEXA) scan. The bone turnover markers were assessed using procollagen type I N-terminal propeptide and bone-specific alkaline phosphatase as bone formation markers and serum β-carboxy-terminal cross-linking telopeptide of type I collagen, urinary free pyridinolone: creatinine and free deoxypyridinoline: creatinine ratios as bone resorption markers.

Osteopenia/osteoporosis was observed in 50% patients. The average age at the diagnosis of osteoporosis was 33 years and T-score at lumbar vertebra as low as – 3.5. In addition, a further 14% showed rapid bone loss on their most recent DEXA-scan report. There was a male preponderance with male to female ratio of 3:1, respectively. There was no significant difference between the three types of GSD. Bone turnover markers result showed no significant correlation with BMD.

Our result indicates higher incidence of osteopenia/osteoporosis in patients with GSD and with prolonged survival there may be a need to consider prophylactic measure to address changes in BMD and consider treatment to reduce fracture risk.