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Background: Heterozygous gain-of-function mutations in the glucokinase (GCK) gene cause hyperinsulinaemic hypoglycaemia (GCK-HI), while loss-of-function mutations lead to a monogenic type of diabetes (GCK-MODY). We, herein, report a heterozygous GCK gene mutation in a large family with GCK-MODY and insulinoma in one individual from the same family. Patients and methods: The proband, an 11-year-old male, was referred for asymptomatic mild hyperglycemia (fasting glucose:121 mg/dL) and HbA1c of 6.1%. Segregation analysis of the family revealed multiplex members with asymptomatic fasting hyperglycaemia or non-insulin-dependent diabetes and 33-year-old maternal uncle of the proband case had a history of distal pancreatectomy due to the diagnosis of insulinoma. His preoperative investigations were revealed fasting glucose of 31 mg/dL, insulin: 7µU/mL, C-peptide: 2.6 mg/dL, and a low HbA1c(4.0%) which was suggestive for recurring hypoglycaemia episodes. Post-pancreatectomy he developed mild fasting hyperglycemia (115-136 mg/dL). Results: Genetic analysis revealed heterozygous p.Ser453Leu(c.1358C> T) mutation in the GCK gene in the proband. In segregation analysis, the identical heterozygous p.Ser453Leu(c.1358C> T) GCK gene mutation was detected in all of the other affected family members for whom a DNA analysis was applicable. The maternal uncle was first diagnosed with insulinoma and underwent a pancreatectomy. He also had an identical mutation in a heterozygous state. Conclusion: We, to the best of our knowledge, firstly identified these two entirely distinct phenotypes of glucose metabolism, GCK-MODY and GCK-HI, due to an identical heterozygous p.Ser453Leu (c.1358C> T) mutation in the GCK. Further studies required to elucidate this new phenomenon and understanding the genotype-phenotype relationship of GCK gene mutations.
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Introduction: Biotin treatment causes false-low or false-high results in some immunoassays methods. This phenomenon is called as biotin interference. In the present article, a seven-month-old male, with renal failure and laboratory hyperthyroidism due to biotin interference is presented. Case report: High free T4 (fT4), free T3 (fT3), anti-thyroid peroxidase antibody (anti-TPO), anti-thyroglobulin antibody (anti-TG) and low thyroid stimulating hormone (TSH) levels were detected in a seven-month-old male patient who has metabolic acidosis, renal failure, and suspected of metabolic disease. Anti-thyroid drug therapy was started. However, when he was re-evaluated due to the absence of euthyroidism with anti-thyroid therapy (methimazole 0.8 mg/kg /day), it was found that the patient had been given 20 mg/day biotin for acidosis for two months. Biotin interference was considered in hormone measurement. Thyroid function tests were found to be normal 12 days after discontinuation of biotin therapy. Conclusion: Immunoassay measurements which use biotin should be done 2-7days after the last dose of biotin in patients under biotin treatment, but this time may need be much longer in renal failure patients. During this period or if the biotin therapy cannot be stopped, alternative methods should be preferred for analysis.
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BACKGROUND: Relative adrenal insufficiency (RAI) is the inadequate production of cortisol due to dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis during a severe illness. We evaluated the HPA axis and RAI in a tertiary pediatric intensive care unit (PICU). METHODS: A total of 100 PICU patients were included in this prospective cohort study. Basal serum levels of adrenocorticotropic hormone (ACTH), cortisol values were compared with those in the control group. A low-dose ACTH stimulation test was performed in patients with basal cortisol levels below 18 µg/dL. RESULTS: The basal cortisol levels of the PICU patients were significantly higher than those of the control group (P < 0.05). All tested patients (n= 24) had delta cortisol levels > 9 µg/dL and a peak cortisol response > 18 µg/dL. Basal cortisol levels were positively correlated with Pediatric Risk of Mortality (PRISM) III scores (P < 0.05; r = 0.363). The basal or stimulated cortisol levels of the patients who received glucocorticoid treatment were higher than the cut-off levels. CONCLUSIONS: High basal or stimulated cortisol levels are indicative of disease severity in the acute phase of stress. Patients with very high cortisol levels should be particularly carefully monitored because of the high mortality risk.
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AIM: To compare the cyclic fatigue resistances of WaveOne Gold (Denstply Sirona, Ballaigues, Switzerland), WaveOne (Dentsply Sirona) and Reciproc (VDW, Munich, Germany) in interrupted reciprocation. METHODOLOGY: Three groups of 18 instruments each of WaveOne Gold Primary, WaveOne Primary and Reciproc R25 were subjected to cyclic fatigue tests in reciprocation and interrupted reciprocation. The instruments in group 1 were tested in reciprocation, whereas in groups 2 and 3, reciprocation was interrupted for 1 s in every 5 s and 10 s, respectively. Cyclic fatigue resistance was tested using dynamic test devices in stainless steel, curved canals (60°, r = 5 mm) until fracture, and the time to fracture values were recorded. The lengths of the fractured tips were also recorded, and fractured surfaces were examined with a scanning electron microscope (SEM). Data were evaluated by one-way analysis of variance and Tukey's tests. RESULTS: The cyclic fatigue resistance of WaveOne Gold Primary was not affected by the interruptions (P > 0.05) and exhibited significantly greater cyclic fatigue resistance than WaveOne Primary and Reciproc R25 in all groups (P < 0.05). Interruptions reduced the cyclic fatigue resistance of WaveOne Primary and Reciproc R25 significantly (P < 0.05). CONCLUSION: Interrupted reciprocation reduced the cyclic fatigue resistance of Reciproc R25 and WaveOne Primary. The cyclic fatigue resistance of WaveOne Gold Primary was greater than that of WaveOne Primary and was not dependent on the occurrence of interruptions.
