Mutation update and uncommon phenotypes in a French cohort of 96 patients with WFS1-related disorders.

WFS1 mutations are responsible for Wolfram syndrome (WS) characterized by juvenile-onset diabetes mellitus and optic atrophy, and for low-frequency sensorineural hearing loss (LFSNHL). Our aim was to analyze the French cohort of 96 patients with WFS1-related disorders in order (i) to update clinical and molecular data with 37 novel affected individuals, (ii) to describe uncommon phenotypes and, (iii) to precise the frequency of large-scale rearrangements in WFS1. We performed quantitative polymerase chain reaction (PCR) in 13 patients, carrying only one heterozygous variant, to identify large-scale rearrangements in WFS1. Among the 37 novel patients, 15 carried 15 novel deleterious putative mutations, including one large deletion of 17,444 base pairs. The analysis of the cohort revealed unexpected phenotypes including (i) late-onset symptoms in 13.8% of patients with a probable autosomal recessive transmission; (ii) two siblings with recessive optic atrophy without diabetes mellitus and, (iii) six patients from four families with dominantly-inherited deafness and optic atrophy. We highlight the expanding spectrum of WFS1-related disorders and we show that, even if large deletions are rare events, they have to be searched in patients with classical WS carrying only one WFS1 mutation after sequencing.

Use of the continuous glucose monitoring system to treat insulin autoimmune syndrome: quantification of glucose excursions and evaluation of treatment efficacy.

BACKGROUND: Autoimmune hypoglycaemia, based on the presence of autoantibodies directed against endogenous insulin (insulin autoimmune syndrome or Hirata's disease), is a rare cause of hypoglycaemia. Treatment of the disease is not standardized and various therapeutic options have been proposed. We wondered whether using a continuous glucose-monitoring system could help quantify precisely glucose excursions and allow evaluation of treatment efficacy. CASE REPORT: A 44-year-old Caucasian patient with insulin autoimmune syndrome was studied for 7 days using a continuous glucose monitoring system under various treatment regimens, i.e. diet modification, high-dose corticosteroids, alpha-glucosidase inhibitors, and plasmapheresis. CONCLUSION: Continuous glucose monitoring system data confirmed that insulin autoimmune syndrome alternated between periods of prandial hyperglycaemia and interprandial hypoglycaemia. Alpha glucosidase inhibitors and plasmapheresis were more potent in limiting glucose excursions than corticosteroid or diet-only treatments. The continuous glucose monitoring system appears to be a useful tool in the management of insulin autoimmune syndrome.

Culturomics identified 11 new bacterial species from a single anorexia nervosa stool sample.

The rebirth of bacterial culture has been highlighted successively by environmental microbiologists, the design of axenic culture for intracellular bacteria in clinical microbiology, and, more recently, by human gut microbiota studies. Indeed, microbial culturomics (large scale of culture conditions with the identification of colonies by MALDI-TOF or 16S rRNA) allowed to culture 32 new bacterial species from only four stool samples studied. We performed culturomics in comparison with pyrosequencing 16S rRNA targeting the V6 region on an anorexia nervosa stool sample because this clinical condition has never been explored before by culture, while its composition has been observed to be atypical by metagenomics. We tested 88 culture conditions generating 12,700 different colonies identifying 133 bacterial species, with 19 bacterial species never isolated from the human gut before, including 11 new bacterial species for which the genome has been sequenced. These 11 new bacterial species isolated from a single stool sample allow to extend more significantly the repertoire in comparison to the bacterial species validated by the rest of the world during the last 2 years. Pyrosequencing indicated a dramatic discrepancy with the culturomics results, with only 23 OTUs assigned to the species level overlapping (17 % of the culturomics results). Most of the sequences assigned to bacteria detected only by pyrosequencing belonged to Ruminococcaceae, Lachnospiraceae, and Erysipelotrichaceae constituted by strictly anaerobic species, indicating the future route for culturomics. This study revealed new bacterial species participating significantly to the extension of the gut microbiota repertoire, which is the first step before being able to connect the bacterial composition with the geographic or clinical status.

Correlation between body mass index and gut concentrations of Lactobacillus reuteri, Bifidobacterium animalis, Methanobrevibacter smithii and Escherichia coli.

BACKGROUND: Genus and species level analysis is the best way to characterize alterations in the human gut microbiota that are associated with obesity, because the clustering of obese and lean microbiotas increases with the taxonomic depth of the analysis. Bifidobacterium genus members have been associated with a lean status, whereas different Lactobacillus species are associated both with a lean and an obese status. OBJECTIVES AND METHODS: We analyzed the fecal concentrations of Bacteroidetes, Firmicutes, Methanobrevibacter smithii, the genus Lactobacillus, five other Lactobacillus species previously linked with lean or obese populations, Escherichia coli and Bifidobacterium animalis in 263 individuals, including 134 obese, 38 overweight, 76 lean and 15 anorexic subjects to test for the correlation between bacterial concentration and body mass index (BMI). Of these subjects, 137 were used in our previous study. FINDINGS: Firmicutes were found in >98.5%, Bacteroidetes in 67%, M. smithii in 64%, E. coli in 51%, Lactobacillus species between 17 and 25% and B. animalis in 11% of individuals. The fecal concentration of Lactobacillus reuteri was positively correlated with BMI (coefficient=0.85; 95% confidence interval (CI) 0.12-0.58; P=0.02) in agreement with what was reported for Lactobacillus sakei. As reported, B. animalis (coefficient=-0.84; 95% CI -1.61 to -0.07; P=0.03) and M. smithii (coefficient=-0.43, 95% CI -0.90 to 0.05; P=0.08) were negatively associated with the BMI. Unexpectedly, E. coli was found here for the first time to negatively correlate with the BMI (coefficient=-1.05; 95% CI -1.60 to -0.50; P<0.001). CONCLUSION: Our findings confirm the specificity of the obese microbiota and emphasize the correlation between the concentration of certain Lactobacillus species and obesity.

Dental implants and diabetes: conditions for success.

AIMS: To assess the success of dental-implant treatment in patients with diabetes. BACKGROUND: Dental-implant treatment is an efficient means of replacing lost teeth. However, diabetes can be considered a relative contraindication for this type of treatment because of the slightly higher failure rate compared with populations without diabetes. RECOMMENDATIONS: Prerequisite selection of suitable diabetic patients, eradication of co-morbidities (poor oral hygiene, cigarette-smoking, periodontitis), stabilization of glycaemic control (HbA(1c) at around 7%) and preventative measures against infection can increase the success of dental implantation in diabetic patients to a satisfactory rate of 85-95%. CONCLUSION: Implant surgery is never a matter of urgency; thus, diabetes patients with the best chances of success should be conjointly selected and prepared by both dental and diabetes clinicians.

Obesity-associated gut microbiota is enriched in Lactobacillus reuteri and depleted in Bifidobacterium animalis and Methanobrevibacter smithii.

BACKGROUND: Obesity is associated with increased health risk and has been associated with alterations in bacterial gut microbiota, with mainly a reduction in Bacteroidetes, but few data exist at the genus and species level. It has been reported that the Lactobacillus and Bifidobacterium genus representatives may have a critical role in weight regulation as an anti-obesity effect in experimental models and humans, or as a growth-promoter effect in agriculture depending on the strains. OBJECTIVES AND METHODS: To confirm reported gut alterations and test whether Lactobacillus or Bifidobacterium species found in the human gut are associated with obesity or lean status, we analyzed the stools of 68 obese and 47 controls targeting Firmicutes, Bacteroidetes, Methanobrevibacter smithii, Lactococcus lactis, Bifidobacterium animalis and seven species of Lactobacillus by quantitative PCR (qPCR) and culture on a Lactobacillus-selective medium. FINDINGS: In qPCR, B. animalis (odds ratio (OR)=0.63; 95% confidence interval (CI) 0.39-1.01; P=0.056) and M. smithii (OR=0.76; 95% CI 0.59-0.97; P=0.03) were associated with normal weight whereas Lactobacillus reuteri (OR=1.79; 95% CI 1.03-3.10; P=0.04) was associated with obesity. CONCLUSION: The gut microbiota associated with human obesity is depleted in M. smithii. Some Bifidobacterium or Lactobacillus species were associated with normal weight (B. animalis) while others (L. reuteri) were associated with obesity. Therefore, gut microbiota composition at the species level is related to body weight and obesity, which might be of relevance for further studies and the management of obesity. These results must be considered cautiously because it is the first study to date that links specific species of Lactobacillus with obesity in humans.

Non-traumatic rhabdomyolysis and diabetes.

The present clinical report describes the case of a spontaneously resolving rhabdomyolysis episode in a type 1 diabetic patient, who presented with multiple risk factors of this muscle complication, including uncontrolled brittle diabetes with sequences of hyper- and hypoglycaemic episodes in the same day, caloric restriction and intensive exercise. It should be borne in mind that rhabdomyolysis is not particularly rare in diabetes and can be severe. To raise clinicians' awareness of a possible rhabdomyolysis diagnosis, the various clinical conditions that are likely to lead to this complication in diabetic patients are also reviewed here.

Specific adipocytokines profiles in patients with hyperactive and/or binge/purge form of anorexia nervosa.

OBJECTIVE: The aim of our study was to determine whether eating behaviors and/or physical activity level may explain contradicting results in adipocytokines levels in anorexia nervosa (AN). SUBJECTS/METHODS: Fasting levels of circulating adipocytokines (adiponectin, resistin and leptin), insulin, glucose, C-reactive protein, cytokines (tumor necrosis factor-alpha and interleukin (IL)-1beta), body composition and resting energy expenditure were measured in 24 women AN patients and 14 women controls. These parameters were compared according to AN subtypes: 15 patients with restrictive (R-AN) form versus 9 patients with binge/purge (BP-AN) form; 15 patients with hyperactive (H-AN) form versus 9 patients with nonhyperactive (NH-AN) form. RESULTS: BP-AN patients had significantly higher serum adiponectin levels compared with R-AN patients (P<0.05), and H-AN patients had higher serum leptin and lower serum resistin levels compared with NH-AN patients (P<0.05 for both). CONCLUSIONS: Our study shows specific adipocytokines profiles depending on the subtype of AN: restrictive versus binge/purge and hyperactive versus Nonhyperactive forms. We suggest that these biological signatures could interfere with the outcome of the disease.

[Propositions for the standardized expression of HbA 1c results]. / Propositions pour l'expression standardisée des résultats d'HbA 1c.

The 2007 international consensus about the standardization of HbA(1c) determination and expression of results is progressively implemented in most countries. In France, a common working group of the Société française de biologie clinique (SFBC) and the Société francophone de diabétologie (SFD) has expressed the following recommendations. HbA(1c) results are expressed in percentage of total hemoglobin and in mmol HbA(1c)/mol Hb, but are not converted into estimated average glucose. A table indicating the correspondence between HbA(1c) and estimated average glucose may be given with the results, subject to precautions of interpretation at the individual level.

Parallel increase of plasma apoproteins C-II and C-III in Type 2 diabetic patients.

AIMS: To determine plasma levels of apoprotein (apo) C-II and apoprotein C-III in Type 2 diabetic patients and to examine the clinical and biological factors that are associated with elevated apoC concentrations. METHODS: We measured apoC-II and apoC-III in total plasma and in non-high-density lipoprotein fractions by an immunoturbidimetric assay in 88 Caucasian Type 2 diabetic patients and in 138 healthy control subjects. RESULTS: Plasma levels of both apoC-II and apoC-III were increased in Type 2 diabetic patients. The clinical conditions associated with an increase of plasma apoC-II and apoC-III were abdominal obesity, body mass index, poor glycaemic control and lack of insulin treatment. However, when multivariate analysis was used, plasma apoCs levels correlated with triglyceride levels only. The apoC-III/apoC-II ratio was similar in the Type 2 diabetic and control subjects. CONCLUSIONS: Our study shows the parallel increase of apoC-II and C-III in Type 2 diabetic patients. This parallel increase is related to hypertriglyceridaemia only.

The clinical variability of maternally inherited diabetes and deafness is associated with the degree of heteroplasmy in blood leukocytes.

CONTEXT: Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes with a matrilineal transmission, sensorineural hearing loss, and macular pattern dystrophy due to an A to G transition at position 3243 of mitochondrial DNA (mtDNA) (m.3243A>G). The phenotypic heterogeneity of MIDD may be the consequence of different levels of mutated mtDNA among mitochondria in a given tissue. OBJECTIVE: The aim of the present study was thus to ascertain the correlation between the severity of the phenotype in patients with MIDD and the level of heteroplasmy in the blood leukocytes. PARTICIPANTS: The GEDIAM prospective multicenter register was initiated in 1995. Eighty-nine Europid patients from this register, with MIDD and the mtDNA 3243A>G mutation, were included. Patients with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) or with mitochondrial diabetes related to other mutations or to deletions of mtDNA were excluded. RESULTS: A significant negative correlation was found between levels of heteroplasmy and age of the patients at the time of sampling for molecular analysis, age at the diagnosis of diabetes, and body mass index. After adjustment for age at sampling for molecular study and gender, the correlation between heteroplasmy levels and age at the diagnosis of diabetes was no more significant. The two other correlations remained significant. A significant positive correlation between levels of heteroplasmy and HbA(1c) was also found and remained significant after adjustment for age at molecular sampling and gender. CONCLUSIONS: These results support the hypothesis that heteroplasmy levels are at least one of the determinants of the severity of the phenotype in MIDD.

Significant lower VVH7-like immunoreactivity serum level in diabetic patients: evidence for independence from metabolic control and three key enzymes in hemorphin metabolism, cathepsin D, ACE and DPP-IV.

Low circulating VVH7-like immunoreactivity (VVH7 i.r) level was amazingly observed in human diabetic sera. Here, we examined the impact of diabetes type, clinico-biological features and metabolic control on circulating VVH7 i.r level in this disease. ELISA test was used to measure VVH7 i.r in sera of 120 diabetic patients (type 1 diabetes in 64, type 2 diabetes in 56). Three enzymatic tests were also applied to determine serum cathepsin D (CD), dipeptidyl peptidase IV (DPP-IV) and angiotensin-converting enzyme (ACE) activities. A subgroup of 24 type 1 diabetic patients negative for microalbuminuria and hypertension were submitted to an ambulatory blood pressure monitoring to evaluate the relationship between VVH7 i.r level and blood pressure parameters. The mean serum concentration of VVH7 i.r was drastically reduced in diabetic patients (0.91+/-0.93 micromol/l versus 5.63+/-1.11 micromol/l in controls) (p<0.001). A negative correlation between VVH7 i.r level and daytime diastolic blood pressure existed in type 1 diabetic patients. There was no association of low VVH7 i.r with either type of diabetes or HbA1c level. An increase of cathepsin D activity was found in serum of diabetic patients compared to controls (0.47 U/ml versus 0.15 U/ml, respectively) whereas DPPIV activity was significantly decreased in diabetic sera (50.81 U/ml versus 282.10 U/l respectively). Diminution of VVH7 i.r in sera of diabetic patients was confirmed but still remained unexplained. Relationships between higher systolic blood pressure and decrease of VVH7 i.r reinforce the need to investigate this pathway in this disease to elucidate its role in macro- and micro-angiopathy.

Retinal and renal complications in patients with a mutation of mitochondrial DNA at position 3,243 (maternally inherited diabetes and deafness). A case-control study.

AIMS/HYPOTHESIS: We assessed the prevalence and determinants of retinal and renal complications in patients with maternally inherited diabetes and deafness (MIDD). METHODS: This was a multicentre prospective study comparing the prevalence of retinopathy and renal disease in 74 patients with MIDD and 134 control patients matched for sex, age and clinical presentation at onset of diabetes, duration of diabetes and current treatment. Comparisons were adjusted for HbA(1c) and hypertension. RESULTS: In MIDD patients, HbA(1c) (7.6 +/- 1.6 vs 8.5 +/- 2.0%, p < 0.002), systolic blood pressure (126.6 +/- 16.2 vs 133.1 +/- 17.3 mmHg, p < 0.007) and prevalence of hypertension (33.8 vs 64.2%, p < 0.0001) were lower than in control patients. Prevalence of diabetic retinopathy was 3.7-fold lower in MIDD patients (6/74, 8 vs 40/134, 29.6%, p < 0.0001). Differences between groups remained significant after adjustment for hypertension, systolic blood pressure and HbA(1c). In MIDD, urinary albumin excretion (314.8 vs 80.1 mg/24 h, p = 0.035) and creatinine plasma levels (103.5 vs 82.2 micromol/l, p = 0.0178) were higher and GFR was lower. Impaired renal function (GFR <60 ml/min) was four- to sixfold more frequent in MIDD. Differences between MIDD and control diabetic patients further increased when adjusted for HbA(1c) and systolic blood pressure (p < 0.0001). Adjustment for treatment with an ACE inhibitor or angiotensin II receptor antagonist did not modify the results. CONCLUSIONS/INTERPRETATION: This study indicates that diabetic retinopathy is less prevalent in MIDD than in control diabetes. This suggests that retinal alterations due to mitochondrial disease may have a protective role. By contrast, nephropathy is far more frequent in MIDD, suggesting the presence of a specific renal disease independent of diabetic nephropathy.

Aggressive multimodal therapy of sporadic malignant insulinoma can improve survival: a retrospective 35-year study of 12 patients.

AIM: Sporadic malignant insulinoma (SMI) is a rare disease, and the consequent paucity of data in the literature and the development of aggressive treatments for liver metastases have led us to retrospectively analyze a series of 12 cases of SMI. METHODS: Every patient presenting with SMI, according to the WHO 2004 histopathology criteria, between 1970 and June 2005 in Marseille was included in the study. Patients with multiple endocrine neoplasia type 1 (MEN-1) and tumours of uncertain malignant potential were excluded. RESULTS: The ratio of male/female was 4/8, and mean age at diagnosis was 52.5 years. A 48-h fasting test in 10 patients was conclusive in nine, after a mean duration of 12 h 45 min. SMI size ranged from 7-120 mm (mean 30.3mm). Six patients had liver metastases and one had isolated lymph-node invasion. Surgery was performed in 12 patients. Five persisting diseases (mean follow-up of 1.8 years) required other treatments (chemoembolization, radiofrequency thermoablation [RFTA], liver transplantation); one patient relapsed 8.5 years after surgery; six were still in complete remission (mean follow-up of 5.8 years), and one patient had died by the time of the 24-month follow-up. CONCLUSION: Aggressive sequential multimodal therapy can prolong the survival of patients with SMI even in the presence of liver metastases.

Autosomal dominant transmission of diabetes and congenital hearing impairment secondary to a missense mutation in the WFS1 gene.

AIMS: Mutations of the WFS1 gene have been implicated in autosomal dominant diseases, such as low-frequency sensorineural hearing impairment (LFSNHI) and/or diabetes mellitus and/or optic atrophy. The aim was to investigate WFS1 gene sequences in a family with diabetes mellitus and hearing impairment. METHODS: Three members of a family with a maternally inherited combination of diabetes mellitus and hearing impairment, but no specific mutations in its mitochondrial genome, were investigated for mutations in the WFS1 gene. RESULTS: This pedigree, in which the proband had non-insulin-dependent diabetes mellitus and congenital hearing impairment and his mother a triple combination of diabetes mellitus, hearing impairment and optic atrophy, was found to be associated with autosomal dominant transmission of the E864K mutation of the WFS1 gene. CONCLUSIONS: In the light of this confirmatory study, we recommend the systematic analysis of WFS1 gene sequences in patients with parentally inherited diabetes mellitus and deafness (+/- optic atrophy), in particular when diabetogenic mtDNA mutations have been excluded.

Prolonged glucose requirements after intentional glargine and aspart overdose.

Intentional insulin overdose in diabetic patients is a rather rare critical situation. We report the case of a patient suffering from type 1 diabetes who was found comatose with a plasma glucose close to zero after having injected herself massive doses of both aspart and glargine insulin analogues. The prevention of hypoglycaemic episodes in this patient required a long-term glucose infusion (i.e., 59 hours) which significantly exceeds the usual time-effect profile of glargine. This observation emphasizes again that clinicians should be aware of the extremely prolonged action of long acting insulin analogue glargine after intentional massive injection in order to avoid a too early interruption of glucose infusion and a subsequent risk of relapse of severe hypoglycaemic episodes.

Identification of novel mutations in WFS1 and genotype-phenotype correlation in Wolfram syndrome.

Mutations in the WFS1 gene have been reported in Wolfram syndrome (WS), an autosomal recessive disorder defined by early onset of diabetes mellitus (DM) and progressive optic atrophy. Because of the low prevalence of this syndrome and the recent identification of the WFS1 gene, few data are available concerning the relationships between clinical and molecular aspects of the disease. Here, we describe 12 patients from 11 families with WS. We report on eight novel (A214fsX285, L293fsX303, P346L, I427S, V503fsX517, R558C, S605fsX711, P838L) and seven previously reported mutations. We also looked for genotype-phenotype correlation both in patients included in this study and 19 additional WS patients that were previously reported. Subsequently, we performed a systematic review and meta-analysis of five published clinical and molecular studies of WFS1 for genotype-phenotype correlation, combined with our current French patient group for a total of 96 patients. The presence of two inactivating mutations was shown to predispose to an earlier age of onset of both DM and optic atrophy. Moreover, the clinical expression of WS was more complete and occurred earlier in patients harboring no missense mutation.