Nocturnal activity of 11ß-hydroxy steroid dehydrogenase type 1 is increased in type 1 diabetic children.

AIM: The objective of this study was to investigate low-grade inflammation in children with type 1 diabetes (T1D) and its association with cortisol levels as well as its bioavailability through 11ß-hydroxy steroid dehydrogenase type 1 (11ß-HSD1) activity. METHODS: Children with T1D (n=45) and their non-diabetic siblings (n=28) participated in the study. Interleukin-6 (IL-6) and high-sensitivity C-reactive protein (CRPhs) were measured between 1400 and 1800h. Glucocorticoid metabolites were measured in the first morning urine on clinic day and 11ß-HSD1 activity was estimated by tetrahydrocortisol/tetrahydrocortisone (THF/THE) ratio. RESULTS: Diabetic patients presented with an increased THF/THE ratio compared with controls (median: 0.68 [range: 0.45-1.18] vs 0.45 [0.27-0.98], respectively; P<10(-3)). There was no difference between diabetic patients and controls for IL-6 (0.6ng/mL [0.6-6.8] vs 0.6 [0.6-2.2], respectively; P=0.43) and CRPhs (0.4mg/L [0-7.4] vs 0.3 [0-8.2]; P=0.26, respectively). When adjusted for age, gender and BMI, the THF/THE ratio was significantly associated with CRPhs (ß=0.32, P=0.02) in diabetic patients, but not in controls. CONCLUSION: Low-grade inflammation assessed by plasma CRPhs and IL-6 concentrations was not detectable in our cohort of T1D children. Nocturnal 11ß-HSD1 activity was increased and associated with plasma CRPhs concentration in diabetic patients. These results may be explained by either a direct or inflammation-mediated effect of the relative hepatic lack of insulin due to subcutaneous insulin therapy.

Use of an automated ACTH assay for the diagnosis of pituitary and adrenal-related diseases.

OBJECTIVE: To evaluate Liaison Diasorin's automated ACTH assay. DESIGN: We investigated the limit of quantification (LOQ) and simulated the usage of the analyzer using our ACTH results database. RESULTS: The LOQ was close to the cut-off determining Cushing's syndrome ACTH dependency. 25% concentrations of normal subjects were lower than the LOQ. Although biased, the results were concordant with those of an IRMA assay. CONCLUSION: This assay is not sensitive enough to diagnose ACTH-independent Cushing's syndrome.

Erythropoietin levels in endocrinopathies.

BACKGROUND: Erythropoietin (EPO) is an oxygenregulated hormone promoting the differentiation of erythroid progenitor cells. Apart fromhypoxia, few data is available about release by secretagogues including hormones. AIM: To investigate EPO serum concentration in subjects with endocrine diseases. MATERIAL AND METHODS: A retrospective study evaluating serumEPO concentrations in serumleftovers fromsubjects with various endocrine disorders. RESULTS: EPO is not noticeably influenced by thyroid hormone or cortisol concentrations and the relationship with hemoglobin concentration is preserved. In acromegalic patients, the latter is lost but EPO is neither statistically influenced by GH/IGF-I. This may reflect a dual action of GH and/or IGF-I on erythroid progenitors proliferation as well as on EPO synthesis. CONCLUSION: EPO is not noticeably modified by endocrine disorders although GH and or IGF-I may alter EPO relationship with blood hemoglobin concentration.

[Erythropoietin: indications and measurement]. / Erythropoïétine : Quand la prescrire ? Pourquoi et comment la doser ?

Erythropoietin (EPO) is the principal haematopoietic growth factor of the red blood cell line. Its major role is to stimulate the red blood cell production. EPO synthesis by peritubular cells in the kidney is regulated by oxygen concentration and must lead adaptation of the organism to face many different physiological situations. An imbalance can lead either to anaemia or polycythemia. Synthetic EPO, so-called recombinant, has definitively changed the treatment in the anaemia of chronic renal failure and regularly find new indications, legal (anaemia of cancer, anaemia of chronic inflammatory syndromes, myelodysplastic syndromes, neurology, cardiology...) or illegal (doping substance in sport). This article reviews the physiology, the role and the indications of EPO in clinical routine practice and define why and how EPO should be measured. We also focus on the analytical requirements for serum EPO concentration determination, especially in the differential diagnosis of polycythemias (secondary polycythemia/Polycythemia Vera).