Endocrine Abstracts

Introduction: Glycogenosis is a group of hereditary diseases affecting the glycogen metabolism, due to mutations in enzymes involved in the transformation and synthesis of glucose (liver and muscle glycogenosis). Brain germ tumors are very infrequent. They are located mainly in pineal and sellar region. Central diabetes insipidus is the most frequent manifestation. Their prognosis and response to combined chemo/radiotherapy treatment are favorable.

Case report: 16-year-old woman referred from pediatrics to follow-up a panhypopituitarism and diabetes insipidus secondary to brain germinoma treated with chemotherapy and radiotherapy, in 2012. Personal history: cavernous angioma in pale nucleus followed up by neurology and oncology and admission in 2014 due to decompensation of glycogenosis (pending to be filied). She received treatment with: Levothyroxine 200 mcg/day, Hydrocortisone 20 mg/day and Ursodeoxycholic acid 300 mg/12h. Physical examination: weight: 57 kg, blood pressure 97/67 mmHg, non-painful hepatomegaly. She presented primary amenorrhea and abdominal ultrasound showed an atrophic uterus, linear endometrium with preserved tubes and atrophic ovaries. The gynecologist advised gonadal function restoration if not contraindicated other way. She was also referred to the Metabolopathy Unit where they requested a genetic study, densitometry and advised against hormone replacement therapy to reestablish sexual function. Blood tests: Glycemia 96 mg/dl, Creatinine 0.32 mg/dl, Na 142 mEq/L, K 3.99 mEq/L, normal lipid profile, calcium 9.69 mg/dl, plasma osmolarity 329 mOsmol/kg, TSH 10.3 μUI/ml, T4L 0.4 ng/ml, FSH 1.3 mUI/ml, LH 0.46 mUI/ml, Prolactin 11.5 ng/ml, Estradiol <11.8 pg/ml, Cortisol basal 0.5 ng/ml, ACTH 16 pg/ml, GH 0.03 ng/ml, IGF-1 <25 ng/ml, urine osmolarity 212 mOsmol/kg. She had polydpisia-polyuria, and recognice correct therapeutic compliance so we requested a malabsorption study and Levothyroxine absorption test with 200 g during a week (day 1: TSH 7.38 μUI/ml, T4L 0.5 ng/ml and day 7: TSH 1.5 μUI/ml, T4L 1.06 ng/ml). We confirmed hormonal imbalance due to poor adherence to treatment. We adjusted treatment: Levothyroxine 150 μg/day and Desmopressin flash 120 μg/day (according to diuresis). Supplementary tests included: densitometry (normal), pituitary MRI (no tumor remnants with empty sella) and analytical (TSH 0.01 μUI/ml, T4L 1.8 ng/ml, normal ions and lipid profile, GH 0.02 ng/ml, IGF-1 <25 ng/ml). We started treatment with 0.4 mg/day growth hormone, titrating doses according to IGF-1 levels, up to the current dose of 0.6 mg/day), but persisting without restoration of the gonadal axis (due to its contraindication in glycogenoses). In the last medical visit, the patient presented good general condition, without hypoglycaemia, good therapeutic compliance and nutritional recommendations. Genetic study still pending. In these cases, the multidisciplinary approach of the patient is important for an adequate diagnostic-therapeutic orientation.