[Graves' orbitopathy: diagnosis, epidemiology and treatments]. / L'orbitopathie basedowienne: diagnostic, épidémiologie et principes de traitement.

Graves' orbitopathy is the most common extra-thyroid complication of Graves' disease and can be a potentially severe affection, therefore requiring multidisciplinary treatment support according to clinical activity and severity assessments. This review proposes to determine physiopathological mechanisms, epidemiology and therapeutic management of Graves' orbitopathy.

[Diagnostic approach and therapeutic management of hyperthyroidism]. / Démarche diagnostique et prise en charge thérapeutique de l'hyperthyroïdie.

Hyperthyroidism is a frequent clinical situation that can be expressed by various signs and it is generally easy to diagnose. This review proposes to explain the diagnostic approach that affects therapeutic management by separating diseases with homogeneous and nodular thyroid.

Relationship between renal capacity to reabsorb glucose and renal status in patients with diabetes.

AIMS: Interindividual variability in capacity to reabsorb glucose at the proximal renal tubule could contribute to risk of diabetic kidney disease. Our present study investigated, in patients with diabetes, the association between fractional reabsorption of glucose (FRGLU) and degree of renal disease as assessed by urinary albumin excretion (UAE) and estimated glomerular filtration rate (eGFR). METHODS: FRGLU [1-(glucose clearance/creatinine clearance)] was assessed in 637 diabetes patients attending our tertiary referral centre, looking for correlations between FRGLU and UAE (normo-, micro-, macro-albuminuria) and Kidney Disease: Improving Global Outcomes (KDIGO) eGFR categories: >90 (G1); 90-60 (G2); 59-30 (G3); and<30-16 (G4) mL/min/1.73 m2. Patients were stratified by admission fasting plasma glucose (FPG) into three groups: low (<6mmol/L); intermediate (6-11mmol/L); and high (>11mmol/L). RESULTS: Median (interquartile range, IQR) FRGLU levels were blood glucose-dependent: 99.90% (0.05) for low (n=106); 99.90% (0.41) for intermediate (n=288); and 96.36% (12.57) for high (n=243) blood glucose categories (P<0.0001). Also, FRGLU increased with renal disease severity in patients in the high FPG group: normoalbuminuria, 93.50% (17.74) (n=135); microalbuminuria, 96.56% (5.94) (n=77); macroalbuminuria, 99.12% (5.44) (n=31; P<0.001); eGFR G1, 94.13% (16.24) (n=111); G2, 96.35% (11.94) (n=72); G3 98.88% (7.59) (n=46); and G4, 99.11% (2.20) (n=14; P<0.01). On multiple regression analyses, FRGLU remained significantly and independently associated with UAE and eGFR in patients in the high blood glucose group. CONCLUSION: High glucose reabsorption capacity in renal proximal tubules is associated with high UAE and low eGFR in patients with diabetes and blood glucose levels>11mmol/L.

Efficacy and adherence of glucagon-like peptide-1 receptor agonist treatment in patients with type 2 diabetes mellitus in real-life settings.

Despite the availability of a large number of therapeutic options throughout the world, rates of optimal glycaemic control in adult patients with type 2 diabetes mellitus remain low. Delays in treatment intensification to insulin and low adherence to insulin regimes, which are well-documented contributors to poor glycaemic control, are in many cases driven by fear of hypoglycaemic events, weight gain and injections. Over the last 10 years, injectable glucagon-like peptide-1 receptor agonists (GLP1-RAs) have emerged as alternatives to basal insulin for treatment intensification in patients inadequately controlled with oral antidiabetic drugs. As a class, GLP1-RAs are associated with weight loss and fewer hypoglycaemic events than insulin. In addition, some of them are available in once-a-week formulations and therefore require fewer injections. However, as randomized controlled trials are not representative of everyday practice, physicians should consider the results of real-life studies to guide their treatment decisions. In this review, while significant variations in efficacy, tolerability and adherence data were noted from one study to another, rates of glycaemic control overall were low. Indeed, our present analysis has suggested that regular re-evaluations of treatment, including response, tolerability, adherence, cost and quality of life, are necessary.

IL-33 receptor ST2 deficiency attenuates renal ischaemia-reperfusion injury in euglycaemic, but not streptozotocin-induced hyperglycaemic mice.

AIM: Kidney hypoxia can predispose to the development of acute and chronic renal failure in diabetes. Ischaemia-reperfusion injury (IRI) causes inflammation, and diabetes is known to exacerbate this inflammatory response in the kidney, whereas alarmin IL-33 could act as an innate immune mediator during kidney IRI. Thus, the present study examined the impact of genetic IL-33 receptor ST2 deficiency (ST2-/-) on renal IRI in euglycaemic and hyperglycaemic mice. METHODS: Hyperglycaemia was induced with streptozotocin (STZ) in adult male C57BL/6JRj wild-type (WT) mice and ST2-/- mice. Unilateral renal IRI was achieved 3months after STZ treatment by left kidney nephrectomy (non-ischaemic control kidney) and clamping of the right renal artery for 32min in STZ- and vehicle-treated animals. At 24h after reperfusion, renal function and injury were determined by levels of plasma creatinine, blood urea nitrogen (BUN) and histological tubule scores. Also, in a complementary pilot clinical study, soluble ST2 concentrations were compared in diabetics and non-diabetics. RESULTS: Urinary albumin was significantly increased in STZ-induced hyperglycaemic mice, regardless of genotypic background. At 24h post-ischaemia, plasma creatinine, BUN and tubular injury were significantly reduced in ST2-/- mice compared with vehicle-treated WT mice, but this protective effect was lost in the STZ-induced hyperglycaemic ST2-/- animals. Plasma concentrations of soluble ST2 were significantly greater in type 2 diabetes patients vs non-diabetics. CONCLUSION: Our data suggest that the IL-33/ST2 pathway exerts differential effects depending on the glucose environment, opening-up new avenues for future research on alarmins and diabetes in ischaemia-related diseases.

Sex hormone levels are not associated with progression of renal disease in male patients with T2DM.

BACKGROUND: Greater renal function decline (RFD) in type 2 diabetes (T2DM) has been suggested in men compared with women, and imbalances in estrogen/androgen levels have been associated with cardiovascular disease mortality in elderly men, but it remains unclear whether sex hormone disequilibrium is related to diabetic nephropathy (DN) in men with T2DM. OBJECTIVE: This study examined the relationship between sex steroid concentrations and renal outcomes in male T2DM patients. POPULATION AND METHODS: Total testosterone (T), total estradiol (E2), sex hormone-binding globulin (SHBG), and total and calculated free (cf) E2/T ratios were compared in 735 male T2DM patients with (n=513) and without (n=222) DN, using a cross-sectional approach. Also, in a pilot complementary prospective nested case-control cohort, total E2/total T and cfE2/cfT were evaluated according to a hard renal outcome (HRO): end-stage renal disease/doubling of baseline serum creatinine (36 HRO cases, 72 HRO controls) and rate of eGFR decline (68 rapid vs 68 slow RFD). RESULT: With the cross-sectional approach, E2 and cfE2 were higher in DN cases vs DN controls (95.5 vs 86.8pmol/L [P=0.0246] and 2.59 vs 2.36pmol/L [P=0.005], respectively). The difference in E2 persisted on multivariate analysis. In the prospective approach, E2 and T concentrations, and total E2/total T and cfE2/cfT2 ratios did not differ in HRO cases vs controls or in patients with rapid vs slow RFD. CONCLUSION: Although positively related to DN in the cross-sectional analysis, progression of renal disease in male patients with T2DM was not related to either sex hormone levels or aromatase index as reflected by E2/T ratio.

Reassessment of the putative role of BLK-p.A71T loss-of-function mutation in MODY and type 2 diabetes.

AIMS/HYPOTHESIS: MODY is believed to be caused by at least 13 different genes. Five rare mutations at the BLK locus, including only one non-synonymous p.A71T variant, were reported to segregate with diabetes in three MODY families. The p.A71T mutation was shown to abolish the enhancing effect of BLK on insulin content and secretion from pancreatic beta cell lines. Here, we reassessed the contribution of BLK to MODY and tested the effect of BLK-p.A71T on type 2 diabetes risk and variations in related traits. METHODS: BLK was sequenced in 64 unelucidated MODY samples. The BLK-p.A71T variant was genotyped in a French type 2 diabetes case-control study including 4,901 cases and 4,280 controls, and in the DESIR (Data from an Epidemiological Study on the Insulin Resistance Syndrome) and SUVIMAX (Supplementation en Vitamines et Mineraux Antioxydants) population-based cohorts (n = 6,905). The variant effects were assessed by logistic and linear regression models. RESULTS: No rare non-synonymous BLK mutations were found in the MODY patients. The BLK p.A71T mutation was present in 52 normoglycaemic individuals, making it very unlikely that this loss-of-function mutation causes highly penetrant MODY. We found a nominal association between this variant and increased type 2 diabetes risk, with an enrichment of the mutation in the obese diabetic patients, although no significant association with BMI was identified. CONCLUSIONS/INTERPRETATION: No mutation in BLK was found in our MODY cohort. From our findings, the BLK-p.A71T mutation may weakly influence type 2 diabetes risk in the context of obesity; however, this will require further validation.

Intensifying glycaemic control with insulin reduces adiponectin and its HMW isoform moderately in type 2, but not in type 1, diabetes.

INTRODUCTION: As the impact of diabetes control was not tested on adiponectin (ADPN) levels, this study was designed to assess whether or not controlling hyperglycaemia can affect ADPN. PATIENTS AND METHODS: A total of 15 T1D and 48 T2D patients with HbA(1c) greater than 10% were studied at the time of hospitalization for uncontrolled diabetes. Total, and high-, medium- and low-molecular-weight (HMW, MMW, LMW) ADPN were measured at the time of study inclusion, on days 1 and 8, and at 1, 3 and 6 months after insulin treatment. RESULTS: While diabetes control improved, total and HMW APDN decreased on days 1 and 8, but remained steady thereafter in T2D patients. In T1D patients, ADPN levels remained unchanged throughout the study. CONCLUSION: Glycaemic control with insulin reduces ADPN in T2D patients in the short-term, but was ineffective in T1D.

A polymorphism in the gene encoding carnosinase (CNDP1) as a predictor of mortality and progression from nephropathy to end-stage renal disease in type 1 diabetes mellitus.

AIMS/HYPOTHESIS: Homozygosity for a five leucine repeat (5L-5L) in the carnosinase gene (CNDP1) has been found to be cross-sectionally associated with a low frequency of diabetic nephropathy (DN), mainly in type 2 diabetes. We prospectively investigated in patients with type 1 diabetes whether: (1) 5L-5L is associated with mortality; (2) there is an interaction of 5L-5L with DN or sex for prediction of mortality; and (3) 5L-5L is associated with progression to end-stage renal disease (ESRD). METHODS: In this prospective study in white European patients with type 1 diabetes, individuals with DN were defined by persistent albuminuria ≥ 300 mg/24 h. Controls without nephropathy were defined by persistent (>15 years) normoalbuminuria < 30 mg/24 h. Leucine repeats were assessed with a fluorescent DNA analysis system. Onset of ESRD was defined by need to start chronic dialysis or kidney transplantation. RESULTS: The study involved 916 patients with DN and 1,170 controls. During follow-up for 8.8 years, 107 patients (14%) with 5L-5L died compared with 182 patients (13.8%) with other genotypes (p = 0.99). There was no significant interaction of 5L-5L with DN for prediction of mortality (p = 0.57), but a trend towards interaction with sex (p = 0.08). In patients with DN, HR for ESRD in 5L-5L vs other genotypes was not constant over time, with increased risk for 5L-5L beyond 8 years of follow-up (p = 0.03). CONCLUSIONS/INTERPRETATION: CNDP1 polymorphism was not associated with mortality, and nor was there an interaction of this polymorphism with DN for prediction of mortality in patients with type 1 diabetes. CNDP1 polymorphism predicts progression to ESRD in patients with DN, but only late after baseline measurements.

The polymorphism Arg585Gln in the gene of the sterol regulatory element binding protein-1 (SREBP-1) is not a determinant of ketosis prone type 2 diabetes (KPD) in Africans.

AIM: Ketosis prone type 2 diabetes (KPD) is an atypical form of diabetes described mainly in people of sub-Saharan African origin. Its pathogenesis is unknown, although we have previously described a high prevalence of glucose-6-phosphate-dehydrogenase (G6PD) deficiency in patients with KPD. However, 50% of these deficient patients lacked the G6PD gene mutation. The isoforms of the transcription factor sterol regulatory element binding protein 1 (SREBP-1) are known to stimulate G6PD gene expression, and some polymorphisms in the SREBP-1 gene (SREBF-1) have been described only in Africans. We investigated one of these, the Arg585Gln polymorphism, in a candidate gene approach for KPD. METHODS: We examined the presence of the Arg585Gln polymorphism in SREBF-1 in 217 consecutive unrelated Africans [73 patients with KPD, 80 with classical type 2 diabetes (T2D) and 64 nondiabetic subjects]. Patients underwent clinical and biochemical evaluations, and were assessed for G6PD activity and insulin secretion (glucagon test). RESULTS: There were no differences in frequency of the Arg585Gln polymorphism and the 585Gln allele among the three groups (allele frequency: KPD: 0.089, T2D: 0.031, nondiabetic group: 0.070; P=0.1). When the 585Gln allele frequency was compared separately between patients with KPD and those with T2D, it was significantly higher in the former (P=0.032). There was no difference between carriers and noncarriers of the 585Gln allele regarding G6PD activity and insulin secretion. CONCLUSION: The results of this exploratory study show that the polymorphism Arg585Gln in SREBF-1 is not associated with the KPD phenotype. Further studies in larger populations are needed to confirm our findings.

[Effects of smoking on the thyroid gland, digestive system, kidney and bone]. / Effets du tabagisme sur la thyroïde, le tube digestif, le rein et l'os.

INTRODUCTION: In addition to being a major cardiovascular risk factor, smoking promotes or worsens thyroid, digestive, renal and bone diseases. BACKGROUND: Smoking is positively associated with hyperthyroidism. It is associated with Graves' disease and it especially increases the risk of the development of severe exophthalmos. In contrast, smoking might exert a protective action for thyroid carcinoma. Smoking increases the severity of hepatic lesions in patients with chronic hepatitis C. Smoking accelerates the progression of primary biliary cirrhosis and increases the risk of hepatocellular carcinoma. Smoking increases risk of both hyperplastic and adenomatous polyps. While Crohn's disease is associated with smoking, ulcerative colitis is largely a disease of non smokers. Smoking increases risk of development of both renal cell carcinoma and chronic nephropathies, particularly in types 1 and 2 diabetes. Smoking is a risk factor for decreased bone density and is associated with a significantly increased risk of fracture. Smoking is related to the development of rheumatoid arthritis and may adversely influence its severity. CONCLUSIONS: Smoking might be considered a risk factor for the development of several thyroid, digestive, renal and bone diseases. Consequently, smoking prevention and cessation programs must be strongly encouraged among the patients concerned.

[Microalbuminuria and urinary albumin excretion: French guidelines]. / Microalbuminurie et excrétion urinaire d'albumine: recommandations pour la pratique clinique.

UNLABELLED: Measurement of urinary albumin excretion (UAE) may be done on a morning urinary sample or on a 24 hour-urine sample. Values defining microalbuminuria are: - 24-hour urine sample: 30-300 mg/24 hours - Morning urine sample: 20-200 mg/mL or 30-300 mg/g creatinine or 2.5-25 mg/mmol creatinine (men) or 3.5-35 mg/mol (women). - Timed urine sample: 20-200 mug/min. The optimal use of semi-quantitative urine test-strip is not clearly defined. It is generally believed that microalbuminuria reflects a generalized impairment of the endothelium; however, no definite proof has been shown in humans. In diabetic subjects, microalbuminuria is a marker of increased risk of cardiovascular (CV) and renal morbidity and mortality in type 1 and type 2 diabetic subjects. The increase in UAE during follow-up is also a marker of CV and renal risk in type 1 and type 2 diabetic subjects; its decrease during follow-up is associated with lower risks. In non-diabetic subjects, microalbuminuria is a marker of increased risk for diabetes mellitus, deterioration of the renal function, CV morbidity and all-cause mortality. It is a marker of increased risk for the development of hypertension in normotensive subjects, and is associated with unfavorable outcome in patients with cancer and lymphoma. Persistence or elevation of UAE overtime is associated with deleterious outcome in some hypertensive subjects. Measurement of UAE may be recommended in hypertensive subjects with 1 or 2 CV risk factors in whom CV risk remains difficult to assess, and in those with refractory hypertension: microalbuminuria indicates a high CV risk and must lead to strict control of arterial pressure. Studies focused on microalbuminuria in non-diabetic, non-hypertensive subjects are limited; most of them suggest that microalbuminuria predicts CV complications and deleterious outcome as it is in diabetic or hypertensive subjects. Subjects with a history of CV or cerebrovascular disease have an even greater CV risk if microalbuminuria is present than if it is not; however, in all cases, therapeutic intervention must be aggressive regardless of whether microalbuminuria is present or not. It is not recommended to measure UAE in non-diabetic non-hypertensive subjects in the absence of history of renal disease. Monitoring of renal function (UAE, serum creatinine and estimation of GFR) is annually recommended in all subjects with microalbuminuria. MANAGEMENT: in patients with microalbuminuria, weight reduction, sodium restriction (< 6 g/day), smoking cessation, strict glucose control in diabetic subjects, strict arterial pressure control are necessary; in diabetic subjects: use of maximal doses of ACEI or ARB are recommended; ACEI/ARB and thiazides have synergistic actions on arterial pressure and reduction of UAE; in non-diabetic subjects, any of the five classes of anti-hypertensive medications (ACEI, ARB, thiazides, calcium channel blockers or beta-blockers) can be used.

To what extent should we lower HbA1c in diabetic subjects?

Current recommendations regarding glycemic control suggest that HbA(1c) should be lower than 6.5%. This is supported by data regarding microvascular disease, namely retinopathy rather than nephropathy. The question is not completely solved regarding cardiovascular diseases, where a strategy of very low HbA(1c) ("the lower the better") is expected to be effective. Some ongoing studies will help to answer these unsolved questions.

Diagnostic strategy for growth hormone deficiency: relevance of IGF-1 determination as a screening test.

BACKGROUND: Adult growth hormone (GH) deficiency must be diagnosed before prescribing therapeutic recombinant human GH. We studied the clinical relevance of a diagnostic strategy for growth hormone deficiency (GHD) using IGF-1 determination as a first step. METHODS: In 2000 and 2001, we tested 142 adult patients with hypothalamo-pituitary disorders for somatotropic function using Insulin Tolerance Test (ITT), the reference test for the diagnosis of GHD, with concomitant Insulin-like growth factor-1 (IGF-1) determination, a marker of somatotropic function. Patients were classified as GHD (peak GH concentration<3 ng/ml with the ITT) or normal. SETTING: Monocenter prospective study in a tertiary referral center. RESULTS: GHD was diagnosed in 61 subjects. Using a ROC curve, a threshold IGF-1 concentration of 175 ng/ml yielded a negative predictive value of 89+/-5%. A diagnostic strategy with IGF-1 determination as the first step followed by ITT for patients with an IGF-1 concentration below 175 ng/ml missed five of the 61 GHD patients, avoided 46/142 ITT and reduced the cost of diagnosis by 15%. CONCLUSION: We propose the use of a strategy consisting of IGF-1 determination followed, if below 175 ng/ml by confirmatory ITT to diagnose GHD in adults.

Microalbuminuria and urinary albumin excretion: French clinical practice guidelines.

Urinary albumin excretion (UAE) may be assayed on a morning urinary sample or a 24 h-urine sample. Values defining microalbuminuria are: 1) 24-h urine sample: 30-300 mg/24 h; 2) morning urine sample: 20-200 mg/ml or 30-300 mg/g creatinine or 2.5-25 mg/mmol creatinine (men) or 3.5-35 mg/mmol (women); 3) timed urine sample: 20-200 mug/min. The optimal use of semi-quantitative urine test-strip is not clearly defined. It is generally believed that microalbuminuria reflects a generalized impairment of the endothelium; however, no definite proof has been obtained in humans. IN DIABETIC SUBJECTS: Microalbuminuria is a marker of increased risk of cardiovascular (CV) and renal morbidity and mortality in type 1 and type 2 diabetic subjects. The increase in UAE during follow-up is associated with greater CV and renal risks in type 1 and type 2 diabetic subjects; its decrease during follow-up is associated with lower risks. IN NON-DIABETIC SUBJECTS: Microalbuminuria is a marker of increased risk for diabetes mellitus, deterioration of renal function, CV morbidity and all-cause mortality. It is a marker of increased risk for the development of hypertension in normotensive subjects, and is associated with unfavorable outcome in patients with cancer and lymphoma. Persistence of elevated UAE during follow-up is associated with poor outcome in some hypertensive subjects. Measurement of UAE may be recommended in hypertensive medium-risk subjects with 1 or 2 CV risk factors in whom CV risk remains difficult to assess, and in those with refractory hypertension: microalbuminuria indicates a high CV risk and must lead to strict control of arterial pressure. Studies focused on microalbuminuria in non-diabetic non-hypertensive subjects are limited; most of them suggest that microalbuminuria predicts CV complications and deleterious outcome. Subjects with a history of CV or cerebrovascular disease have an even greater CV risk if microalbuminuria is present than if it is not; however, in all cases, therapeutic intervention must be aggressive regardless of whether microalbuminuria is present or not. It is not recommended to measure UAE in non-diabetic non-hypertensive subjects in the absence of history of renal disease. Monitoring of renal function (UAE, serum creatinine and estimation of GFR) is recommended annually in all subjects with microalbuminuria. MANAGEMENT: In patients with microalbuminuria, weight reduction, sodium restriction (<6 g per day), smoking cessation, strict glucose control in diabetic subjects, strict arterial pressure control are necessary; in diabetic subjects: use of maximal doses of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) are recommended; ACEI/ARB and thiazides have synergistic actions on arterial pressure and reduction of UAE; in non-diabetic subjects, any of the five classes of anti-hypertensive medications (ACEI, ARB, thiazides, calcium channel blockers or beta-blockers) can be used.