New perspectives for the treatment and follow-up of glycogen storage disease type V: DL-3-hydroxybutyric acid with modified Atkins diet and quadriceps femoris shear wave elastography.

OBJECTIVES: Glycogen storage disease type V is caused by the mutations in muscle glycogen phosphorylase gene. This is the first report which DL-3-hydroxybutyric acid was used in combination with modified Atkins diet for the treatment of a patient with glycogen storage disease type V and quadriceps femoris shear wave elastography was performed to evaluate the treatment efficacy. CASE PRESENTATION: A 13-year-old girl was referred with fatigue and muscle cramps with exercise and there were no pathological findings in physical examination. Creatine kinase levels with 442 U/L. No phosphorylase enzyme activity was detected in muscle biopsy, a homozygous c.1A>G (p.M1V) pathogenic mutation was found in PYGM gene. She was started on DL-3-hydroxybutyric acid and modified Atkins diet at age 16. Her walking and stair climbing capacity increased, the need for rest during exercise decreased. The stiffness of the quadriceps femoris exhibited a reduction. CONCLUSIONS: DL-3-hydroxybutyric acid and modified Atkins diet may provide an alternative fuel and shear wave elastography may be useful in demonstrating treatment efficacy. More clinical and pre-clinical studies are obviously needed to reach more definite conclusions.

Endocrinological and metabolic profile of Gaucher disease patients treated with enzyme replacement therapy.

OBJECTIVES: Gaucher disease (GD) is a lysosomal storage disease caused by glucocerebrosidase (GCase) enzyme deficiency. Gaucher cells transformed from the macrophages by progressive sphingolipid accumulation and infiltrate bone marrow, spleen, liver, and other organs. The accumulation of substrate causes inflammation, compromised cellular homeostasis, and disturbed autophagy. It has been hypothesized that this proinflammatory state of GD leads cytokines and chemokines release. As a result of inflammatory process, the cellular dysfunction caused by disruption of cellular signaling, organelle dysfunction, or autoimmune antibodies may affect endocrine profile of GD patients such as hormone levels, lipid profile, and bone mineral density status. METHODS: A total of 13 patients confirmed to have GD, 12 non-neuronopathic type and one subacute neuronopathic type, were enrolled in our study. RESULTS: The median treatment duration in the enzyme therapy was 13.33 years (9-26 years). At least one endocrinological abnormality was detected in blood tests of nine patients. Hyperinsulinism was the most common finding although fasting blood glucose levels HgbA1c levels were normal in all patients. Two patients had osteopenia, and osteoporosis was detected in two patients. Low HDL levels were detected in six patients, but HDL levels below 23 mg/dL associated with disease severity have been detected in two patients who have not receiving enzyme replacement therapy. None of patients had thyroidal dysfunction. CONCLUSIONS: This study had revealed endocrinological abnormalities in GD patients that have not led any severe morbidity in our patients. However, thyroid hormone abnormalities, insulin resistance, or lipid profile abnormalities may cause unpredictable comorbidities. Endocrinological assessment in GD patients in routine follow-up may prevent possible clinical manifestation in long term as well as can define efficacy of ERT on endocrine abnormalities.