[Endocrine disorders in patients with transfusion-dependent hereditary anemias].

Often transfusions red blood cells in patients with hereditary anemias lead to iron overload, that can cause endocrine complications, such as growth retardation, hypothyroidism, hypogonadism, and disorders of carbohydrate metabolism.Clinical case 1. A boy with transfusion-dependent (TD) Diamond-Blackfan anemia at 16.3 years presented with impaired fasting glucose, growth hormone (GH) deficiency, hypogonadotropic hypogonadism; GH therapy was initiated. At the age of 16.8 years old secondary hypothyroidism, secondary hypocorticism and diabetes mellitus were diagnosed. At 17.2 years continuous glucose monitoring (CGM) detected glucose elevations up to 11.7 mmol/l. Therapy with GH and testosterone ethers was continued; levothyroxine and cortef were stopped by patient. At 17.9 years height was 163 cm; no data supporting hypothyroidism nor hypocorticism; glycaemia within goal range.Clinical case 2. A girl with TD beta-thalassemia major at the age of 11.5 years presented with GH deficiency; GH therapy has been conducted from 12.8 to 15.3 years of age. At 13.8 years retardation of pubertal development was diagnosed. At 15.0 hyperglycemia 7.2 mmol/l was detected; normal results of oral glucose tolerance test (OGTT) were observed; glycemia elevations were up to 9.5 mmol/l according to CGM data. At 16.0 height was 152 cm; because of pubertal development arrest hormone replacement therapy was prescribed.CONCLUSION. Growth, pubertal and carbohydrate metabolism disorders were diagnosed in patients with TD hereditary anemias, that confirms the necessity of regularly endocrine investigation. To detect impairment of carbohydrate metabolism investigation of fasting blood glucose, OGTT, and CGM is recommended; glycated hemoglobin measurement is not considered reasonable.

[Comparative study of glucagon and insulin tests for diagnostics of secondary adrenal insufficiency and growth hormone deficiency in children and adolescents].

BACKGROUND: Diagnostics of growth hormone deficiency (GHD) and secondary adrenal insufficiency (SAI) is based on estimation of peak GH and cortisol concentrations in provocation tests. Russian consensus on diagnostics and treatment of hypopituitarism in children and adolescences recommends to measure GH and cortisol concentrations in every time-point of insulin test (IT). Glucagon test (GT) is discussed in literature as alternative to IT. AIMS: To estimate the possibility to use provocation GT for diagnostics of SAI and GHD in children and adolescents. MATERIALS AND METHODS: We investigated blood and urine cortisol levels, IT, and GT in 20 patients 6.5-17.8 years (Me 13.0 (10.4; 15.3)) after surgery and/or radiology and/or chemical therapy of head and neck tumors; remission for 0.4-7.5 years (Ме 2.1 (1.5; 5.2)). RESULTS: With cut-off point 550 nmol/L sensitivity and specifity of IT was 100% and 60%, GT - 100% and 53% respectively. Minimal cortisol cut-off level for GT with sensitivity 100% was 500 nmol/L, maximal with specifity 100% - 400 nmol/L.Early morning cortisol levels did not exceed 250 nmol/l in 2 patients with SAI; and were above 500 nmol/l in 8 patients without SAI while primary or repeated examination.GHD was reviled by IT in all patients. Maximal GH concentrations in GT and IT did not differ significantly (p>0.05) but GT results of 4 patients exceeded or met cut-off for this test (7 ng/ml).GT was characterized by less severity compared with IT. CONCLUSIONS: For diagnostics of SAI by GT we can advise cut-off points of cortisol level 500 (sensitivity 100%, specifty 53%) and 400 nmol/L (sensitivity 80%, specifity 100%). Measuring of cortisol levels in 2-3 early morning blood samples allows to exclude or to suspect SAI in half of patients before tests. GH peaks in GT can exceed similarly data in IT that needs future investigation.