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M C Vantyghem

Publications and source records attributed to M C Vantyghem.

At least 19 recordsLinked to original sources
PubMed2006

Acute insulin response (AIR): review of protocols and clinical interest in islet transplantation.

Various stimuli have been used in clinical practice to test islet function, including intravenous glucose, arginine--both at basal glucose levels and with the hyperglycaemic clamp, tolbutamide, glucagon and glucagon-like peptide 1. The subsequent first phase insulin response (also termed acute insulin response or AIR) to intravenous glucose or arginine has been quantified in a variety of ways, from the mean serum insulin measured at multiple times after glucose injection to the mean value above baseline of serum insulin at 2 to 10 min. The purpose of this study was to review the different protocols of AIR calculation and their pitfalls, and to assess the results of AIR in the islet transplantation field. By investigating the first phase of insulin secretion, AIR provides both a qualitative and a quantitative approach to insulin secretion. In islet transplantation, post-glucose AIR (AIRg) may predict graft survival while post-arginine AIR (AIRa) may be better correlated with engrafted beta cell mass, despite these facts need to be confirmed. AIRa also limits intravenous hyperglycaemia glucotoxicity. In conclusion, AIR could help to predict the need for a second or third islet injection in islet transplantation. These specific indications, however, need to be confirmed by future studies and completed by other approaches such as insulin sensitivity studies and in vivo morphological assessment of islet mass.

Blood Glucose↗
PubMed2005

[Severe Graves' acropachy and dermopathy. Three case reports].

INTRODUCTION: Traditionally described, severe Graves' acropachy and tibial myxoedema are now only encountered in certain severe forms of Graves' disease, where they can be difficult to diagnose and hence delay the initiation of treatment. OBSERVATIONS: Three patients presented with severe ophthalmopathy, pretibial myxoedema and acropachy of different clinical forms. DISCUSSION: In supplement to the usual biopsies and X-rays, bone scintigraphy provides early diagnosis of acropachy. The severity of the immune disease, the episodes of hypothyroidism and cigarette smoking are the 3 main factors contributing to these extra-thyroid manifestations of Graves' disease. There is currently no treatment that can permanently resolve the functional and aesthetic problems of dermopathy and acropachy.

Adult↗
PubMed2005

[Monogenic severe insulin resistance syndromes].

PURPOSE: To make a point about monogenic insulin resistance syndromes. CURRENT KNOWLEDGE AND KEY POINTS: Extreme insulin resistance syndromes are rare entities. The clinical and biological presentation is similar to that one of metabolic syndrome. Polycystic ovaries syndrome, non-alcoholic liver steatosis, acanthosis nigricans and overall, lipo-atrophic syndrome must be sought. Genetically determined forms are mainly linked to mutations of the insulin receptor gene and to lipoatrophic syndrome-linked mutations. The three syndromes related to mutations of the insulin receptor gene are Type A syndrome, first described by Kahn in young women, whereas leprechaunism and Rabson-Mendenhall syndromes are of neonatal onset. Main insulin resistance syndromes associated with lipo-atrophy are 1) Berardinelli-Seip or congenital generalized lipo-atrophic syndrome linked to mutations of seipin or AGPAT2 gene, 2) Dunnigan or partial familial lipoatrophic syndrome linked to mutations of lamin A/C, or sometimes PPAR gamma gene, and 3) acro-mandibular dysplasia and Köbberling syndrome. FUTURE PROSPECTS AND PROJECTS: In conclusion, an early onset of insulin resistance, especially in association with lipodystrophy must suggest a monogenic insulin resistance syndrome. Outstanding advances in insulin resistance pheno- and genotype identification, despite incomplete yet, offers a better understanding of insulin resistance, atherosclerosis and ageing mechanisms, that should lead to therapeutic improvement.

Diagnosis, Differential↗
PubMed2005

[Cystic fibrosis diabetes in adult].

Cystic fibrosis is an autosomal recessive disorder affecting about 1/3500 case in France. The disease, that affects all epithelia, is responsible for pulmonary tract infections but also pancreas, gut, liver and genital tract abnormalities. It is linked to CFTR gene mutations, inducing unusually high increase of sodium chloride in sweat, used to track down the illness. deltaF508 CFTR mutation, encountered in 70% of cases, is nearly always associated to pancreatic insufficiency with early-onset lung attack. Around 10% of cystic fibrosis cases, whatever the age, are complicated with partially insulinopenic diabetes, favored by pancreatic fibrosis, while one third of patients shows glucose intolerance. After 20 years old, one third of patients suffers from diabetes and one half after 30 years. Diabetes diagnosis is difficult, and requires the fulfillment of oral glucose tolerance test (OGTT). One glycemia greater or equal to 2 g/l, two hours after a 75 g glucose load, established diabetes diagnosis. Indeed, fasting blood glucose and glycated hemoglobin appear as poor diagnosis markers. Despite histological arguments in favor of the mainly mechanical islet disturbances, an increased prevalence of anti-islets auto-antibodies and an increased frequency of HLA DR3/DR4 have been reported in cystic fibrosis population with glucose tolerance troubles. Also, glucose metabolism is influenced by specific factors linked to cystic fibrosis (infection, malnutrition, steroids...). In reason of the silent phase of diabetes, systematic tracking down of diabetes with a yearly OGTT is recommended, all the more so that hyperglycemia appears as a worsening factor of cystic fibrosis. The efficacy of oral anti-diabetic drugs has not been evaluated on large studies. By contrast, some studies argue for insulin therapy as soon as diabetes appears, insulin improving respiratory and nutritional prognosis. In conclusion, the aim of treatment of cystic fibrosis is to prevent the lung function decline by controlling inflammation and infection, to implement endo- and exo-crine pancreas insufficiency, and to improve nutritional status.

Adult↗
PubMed2005

Subcutaneous insulin resistance successfully circumvented on long term by peritoneal insulin delivery from an implantable pump in four diabetic patients.

UNLABELLED: Extreme subcutaneous insulin resistance is a rare syndrome characterized by a severe resistance to subcutaneous (S/C) insulin together with persistence of normal or near normal intravenous (IV) insulin sensitivity. Its pathophysiology is unknown, although increased insulin degrading activity has been reported in the S/C adipose tissue fraction in some cases. Until now, proposed treatments have been disappointing. We report 4 cases who were successfully treated by intraperitoneal (IP) route. METHODS: The diagnosis of subcutaneous insulin resistance was based upon following combined conditions: resistance to hypoglycaemic action of subcutaneous insulin but normal or near normal sensitivity to IV or IP insulin. RESULTS: 4 patients among those followed by EVADIAC group met these criteria: 3 with type 1 diabetes (C peptide=0), the last one with unexplained non insulin-deficient diabetes (no anti-GAD antibodies, C peptide=5 ng/ml). All of them had been treated with subcutaneous insulin therapy without success despite huge doses (up to 4000 IU/day in two patients). The 3 type 1 diabetic patients presented with a history of repeated ketoacidosis episodes. A treatment of insulin mixed with aprotinin had been proposed to 2 patients without success. The IV insulin sensitivity was proved to be normal in two patients by euglycaemic clamp data. A skin biopsy was performed in 1 patient. An accumulation of insulin in the derma was revealed with no increase of degradation products of insulin. In these 4 patients, a dramatic improvement of diabetes control was obtained by IP insulin delivery from an implantable pump (HbA1c decrease by at least 3%). CONCLUSION: Although pathophysiology of the subcutaneous insulin resistance syndrome remains unexplained, our data show that intra-peritoneal insulin therapy from an implantable pump allows diabetes control in patients affected by this uncommon but severely disabling condition.

Adult↗
PubMed2004

Non-esterified fatty acids are deleterious for human pancreatic islet function at physiological glucose concentration.

AIMS/HYPOTHESIS: Whether excess glucose (glucotoxicity) and excess non-esterified fatty acids (lipotoxicity) act synergistically or separately to alter beta-cell function on Type 2 diabetes remains controversial. We examined the influence of non-esterified fatty acids, with or without concomitant increased glucose concentrations, on human islet function and on the expression of genes involved in lipid metabolism. METHODS: Human islets isolated from non-diabetic and non-obese donors were cultured with 5.5, 16 or 30 mmol/l glucose, and when appropriate with 1 or 2 mmol/l non-esterified fatty acids. After 48 h, glucose-stimulated insulin secretion, insulin content, triglyceride content and expression of different genes were evaluated. RESULTS: Non-esterified fatty acids decreased glucose-stimulated insulin secretion, insulin content and increased triglyceride content of human isolated islets, independently from the deleterious effect of glucose. Increased glucose concentrations also decreased glucose-stimulated insulin secretion and insulin content, but had no influence on triglyceride content. Glucose-stimulated insulin secretion of islets appeared to be significantly correlated with their triglyceride content. Glucose and non-esterified fatty acids modified the gene expression of carnitine palmitoyltransferase-I, acetyl-CoA carboxylase, acyl-CoA oxidase and uncoupling protein 2. CONCLUSION/INTERPRETATION: In our model of isolated human islets, increased glucose and non-esterified fatty acids separately reproduced the two major beta-cell alterations observed in vivo, i.e. loss of glucose-stimulated insulin secretion and reduction in islet insulin content. Our results also suggest that this deleterious effect was, at least in part, mediated by modifications in lipid metabolism gene expression.

Base Sequence↗
PubMed2004

Eligibility of diabetic patients receiving dialysis for islet after kidney transplantation.

INTRODUCTION: The aim of this study was to assess the selection of candidates among 38 dialyzed diabetic patients referred between January 1, 1998 and December 31 2002 for kidney followed by islet transplantation (IAK). The main criteria of eligibility for possible IAK were as follows: (1) plasma C-peptide negative; (2) need for a kidney graft; (3) kidney plus whole pancreas transplantation not desired by the patient; and (4) acceptable results of postkidney graft preislet transplantation evaluation. RESULTS: Seventeen of 38 patients with positive C-p diabetes received a kidney graft alone. Among the 21 C-p-negative diabetic patients, 3 were not eligible for kidney transplantation mainly for psychological reasons and 4 were eligible for kidney plus pancreas transplantation. The remaining 14 C-p-negative patients underwent kidney transplantation or had previously undergone kidney transplantation. Among them, 1 had moved away, 1 refused IAK, one had slightly positive stimulation tests, 1 was overweight, 1 had breast cancer, and 1 had postkidney graft complications. Among the remaining 8 of 14 C-p-negative, kidney-engrafted patients listed for IAK, 5 have undergone transplantation, 3 with a pre-Edmonton and 2 with the Edmonton protocol. CONCLUSION: In conclusion among this series of 38 diabetic patients undergoing dialysis, more than 90% were kidney-grafted. Approximately 50% were ineligible for pancreas transplantation or IAK because of a positive C-p, and 20% were enlisted for IAK. These results highlight the importance of C-p determinations in diabetic dialysis patients to identify eligible patients for pancreas transplantation or IAK.

Adult↗
PubMed2004

Eligibility of diabetic patients for islet transplantation alone.

Since the Edmonton protocol, islet transplantation alone (ITA) offers the prospect of adequate glycemic control in type 1 diabetes without kidney failure. Patient motivation, evolution of diabetic complications, and hypoglycemia unawareness have to be balanced against the risks of portal puncture and long-term immunosuppressive therapy. The aim of this work was to assess the profile of 41 type 1 diabetic patients (21 men and 20 women of age 18 to 63 years) for whom islet transplantation was considered, between January 2000 and December 2002. Thirty-one of these patients lived in the area. The patients were divided into 3 groups according to their recruitment: 20, personal initiative (G1); 8, recruited from hospitalization (G2) for marked glycemic imbalance; and 13, (G3) referred by their diabetologist. Among this series of 41 patients, 14 (8 in G1, 4 in G2, and 2 in G3) did not fit the eligibility criteria, mainly because of a positive C-peptide, kidney failure, desire for pregnancy (G1, G3), liver disorders related to alcohol or iron overload related to HFE heterozygosity (G2), or good glycemic balance (G3). Sixteen did not wish to proceed after the first information step, 6 of these being more interested in a pump. Eleven, mainly recruited in G1 or G3, went through the clinical pretransplantation assessment. Among these, 2 have undergone transplantation, another 1 is enlisted. Therefore, it appears that patient motivation and information to the diabetologists are two important issues in the recruitment of patients eligible for islet transplantation. Equally important is the measurement of C-peptide, plasma creatinine, and microalbuminuria.

Adolescent↗
PubMed2004

Selection of diabetic patients for islet transplantation. A single-center experience.

OBJECTIVE: Since the Edmonton protocol, islet transplantation (IT) offers the prospect of adequate glycemic control with no major surgical risk. In our single-center experience of IT, we studied the recruitment of eligible diabetic patients. METHODS: Between 1998 and 2002, we screened 79 diabetic patients that were divided into 2 groups according to their renal status: 41 were not receiving dialysis (ND) while 38 were receiving ongoing dialysis (D). RESULTS: In the ND group, 20 patients initiated the contact with our team, 8 patients were recruited during hospitalization for very poor glycemic imbalance, and 13 were referred by their diabetologist. 14/41 (34%) patients were ineligible for IT either because of very good glycemic balance, detectable C-peptide (C-p), kidney or liver problems, or plans for future pregnancy. 16/41 (39%) did not wish to proceed, 7 of whom were more interested by a pump. 11/41 (27%) were eligible, among which 8 are currently being assessed, 1 is on the waiting list and 2 have been transplanted. In the D group, 17/38 (45%) had a detectable C-p and received a kidney graft alone. Among the remaining 21 C-p negative diabetic patients, 3 were not eligible for kidney transplantation mainly for psychological reasons, and 4 were enlisted for kidney+pancreas transplantation. The remaining 14 C-p negative patients were kidney-transplanted. Among them, 6 were not eligible for IT, mainly for lack of motivation, slightly positive C-p stimulation tests, obesity, cancer, or increased creatininemia. The remaining 8/14 C-p negative kidney-engrafted patients were enlisted for IT. 3 had secondary failure with the pre-Edmonton immunosuppressive (IS) protocol. Five have been transplanted with the Edmonton-like IS regimen. CONCLUSION: Twenty-five per cent of the 79 patients for whom islet transplantation was considered underwent pregraft assessment and 12% (10 patients, 8 kidney-transplanted and 2 islet alone) of the 79 have been transplanted. The main eligibility criteria were undetectable Cpeptide, normal kidney function, average weight, glycemic imbalance, hypoglycemia unawareness, and glycemic brittleness.

Adult↗
PubMed2004

Patients with familial partial lipodystrophy of the Dunnigan type due to a LMNA R482W mutation show muscular and cardiac abnormalities.

Diseases due to mutations in the lamin A/C gene (LMNA) are highly heterogeneous, including neuromuscular and cardiac dystrophies, lipodystrophies, and premature ageing syndromes. In this study we characterized the neuromuscular and cardiac phenotypes of patients bearing the heterozygous LMNA R482W mutation, which is the most frequent genotype associated with the familial partial lipodystrophy of the Dunnigan type (FPLD). Fourteen patients from two unrelated families, including 10 affected subjects, were studied. The two probands had been referred for lipoatrophy and/or diabetes. Lipodystrophy, exclusively observed in LMNA-mutated patients, was of variable severity and limited to postpubertal subjects. Lipodystrophy and metabolic disturbances were more severe in women, even if an enlarged neck was a constant finding. The severity of hypertriglyceridemia and hirsutism in females was related to that of insulin resistance. Clinical muscular alterations were only present in LMNA-mutated patients. Clinical and histological examination showed an invalidating, progressive limb-girdle muscular dystrophy in a 42-yr-old woman that had been present since childhood, associated with a typical postpubertal FPLD phenotype. Six of eight adults presented the association of calf hypertrophy, perihumeral muscular atrophy, and a rolling gait due to proximal lower limb weakness. Muscular histology was compatible with muscular dystrophy in one of them and/or showed a nonspecific excess of lipid droplets (in three cases). Immunostaining of lamin A/C was normal in the six muscular biopsies. Surprisingly, calpain 3 expression was undetectable in the patient with the severe limb-girdle muscular dystrophy, although the gene did not reveal any molecular alterations. At the cardiac level, cardiac septal hypertrophy and atherosclerosis were frequent in FPLD patients. In addition, a 24-yr-old FPLD patient had a symptomatic second degree atrioventricular block. In conclusion, we showed that most lipodystrophic patients affected by the FPLD-linked LMNA R482W mutation show muscular and cardiac abnormalities. The occurrence and severity of the myopathic and lipoatrophic phenotypes varied and were not related. The muscular phenotype was evocative of limb girdle muscular dystrophy. Cardiac hypertrophy and advanced atherosclerosis were frequent. FPLD patients should receive careful neuromuscular and cardiac examination whatever the underlying LMNA mutation.

Adolescent↗
PubMed2003

Extreme subcutaneous insulin resistance: a misunderstood syndrome.

Extreme subcutaneous insulin resistance (SIR) is a rare syndrome characterized by severe resistance to subcutaneous insulin with normal intravenous insulin sensitivity. Its pathophysiology is unknown, though an increased insulin degrading activity has been suggested. We report the case of a 35 year-old female patient with type I diabetes since the age of 3. Despite five shots of insulin/day, the patient progressively developed permanent ketosis related to severe acquired SIR with insulin doses as high as 500 U/day. Subcutaneous infusion of insulin and lispro insulin through an external pump did not improve resistance: HbA(1c) levels remained between 14 and 18% (N<6.5%). After numerous ketoacidotic episodes, continuous ambulatory intravenous insulin infusion was attempted through a central port due to a lack of peripheral venous access. HbAlc improved (8.5%) and daily insulin needs decreased to below 40U. However, the treatment had to be discontinued because of thrombosis and infection at different times. Intraperitoneal insulin infusion with an external pump was then proposed. HbAlc improved to 8% during 18 months but several episodes of catheter infection and encapsulation led to its removal. An intraperitoneal pump was surgically implanted, leading to the stabilization of HbA(1c) to around 8%. An insulin degradation assay did not demonstrate any excess of insulin degrading activity in the patient's or controls' subcutaneous tissue; nevertheless, excessive amounts of insulin were found in the patient's derm compared to controls. This case report of acquired SIR raises the question of its treatment and mechanisms. Regarding treatment, intraperitoneal delivery of insulin appears to be the best solution, but the mechanisms underlying SIR still remain unclear.

Adult↗
PubMed2003

Kinetics of diabetes-associated autoantibodies after sequential intraportal islet allograft associated with kidney transplantation in type 1 diabetes.

OBJECTIVE: Presence or occurrence of pancreas auto-antibodies (aAb) has been shown to be of poor prognosis for islet cell transplantation. The aim of the study was to monitor the kinetics of these aAb after sequential intra-portal islet plus kidney transplantation with pre-Edmonton immunosuppressive regimen in order to determine whether the sequential protocol of transplantation was involved in the occurrence of the immune response. PATIENTS AND METHODS: Three patients with IDDM and a previous (IAK) or simultaneous (SIK) kidney transplantation received 3 or 4 ABO compatible islet preparations. Islets (> 8 000 IEQ/kg post culture) were sequentially transplanted within a 12 day period via a per-cutaneous catheter. Immunosuppressive treatment included cyclosporine, steroïds and mycophenolate. Plasma ICAs, GAD 65, IA2 and C peptide (C-p) levels were monitored. Type II HLA phenotype was determined in donors and recipients. RESULTS: Patient #1 had high anti-GAD levels (26.5 UI/l) before the IAK, while anti-IA2 and ICA levels were low. After the transplantation, C-p levels increased to 4.9 ng/ml at one month before becoming undetectable at 2 months. GAD levels remained high, ICA and IA2 aAb were undetectable. Patients #2 and #3 did not have significant levels of aAb before the islet transplantation. A slight increase in GAD was observed with each islet transplantation, followed by an overt but transient increase in ICA. IA2 levels remained undetectable. Three months after the transplantation and 2 weeks after the increase of ICA, C-p levels, that were >3.4 ng/ml at one month, fell below 0.2 (N: 0.5-2). CONCLUSION: The immunosuppressive regimen used in kidney transplantation is unable to control perfectly anti-pancreas aAb production. Moreover, these results seem to indicate that the benefits of sequential islet transplantation lie more in the increased islet mass they provide than in potential immune benefit.

Adrenal Cortex Hormones↗
PubMed2002

Vitamin D deficiency and severe hyperparathyroidism.

The typical manifestations of severe hypercalcemia with osteitis fibrosa cystica have become exceedingly rare. We describe the case of a woman hospitalized for a tibial tumor with functional impotence, leading to a diagnosis of primary hyperparathyroidism (HPT I) associated with profound vitamin D deficiency. This 31-year-old woman was admitted, after two pregnancies complicated by the HELLP syndrome. Preoperative laboratory values were as follows: calcemia 4.05 mmol/l (2.2-2.6); urinary calcium 30 mmol/24 h (1.25-7.5); parathormone (PTH) 1 195 pg/ml (10-60); and 25 OH-vitamin D 13 nmol/l (22-120). Specific MIBI uptake by the tibial lesion oriented the diagnosis towards a brown tumor. After surgical excision of a parathyroid adenoma and the brown tumor (associated with tibial fracture), calcemia fell to 1.55 mmol/l and normalized after three months. Urinary calcium fell to 0.1 mmol/24 h and remained low during the 2 years following surgery. Vitamin D levels rapidly normalized on supplementation (87 nmol/l). PTH levels fell markedly after surgery but remained higher than normal till 2 years after surgery despite normalization of calcemia three months after. Bone repair, estimated by means of bone densitometry, improved from preoperative Z-score values of - 6.54, - 5.20 and - 3.50 in the left femoral neck, right femoral neck and lumbar spine, respectively, to - 0.20, - 1.55 and - 0.28, respectively, one year after surgery. In conclusion, this case illustrates: 1) the severe osseous expression of HPT probably related to vitamin D deficiency; 2) specific MIBI uptake by the bone lesion, orientating the diagnosis towards a brown tumor; 3) the consequences of vitamin D deficiency on postoperative outcome, with transient severe initial hypocalcemia related to bone calcium avidity; 4) a possible link between HPT and the HELLP syndrome.

Adult↗
PubMed2001

Clinical evaluation of a new sensitive calcitonin assay: study of specificity.

BACKGROUND: Calcitonin (CT) is the most sensitive marker available for medullary thyroid carcinoma, but it lacks specificity. Procalcitonin is the precursor protein of calcitonin. Infections are known to be associated with elevations of procalcitonin. The aim of this study was to evaluate a new sensitive calcitonin assay in a large population and to study the assay specificity in two particular populations: patients with renal failure and patients hospitalized in intensive care units with a high procalcitonin level. METHODS: Using two immunometric assays (A and B) to detect only mature calcitonin, we evaluated the calcitonin level in 488 sera (46 stimulation tests) from 340 subjects. RESULTS: The clinical evaluation showed that the calcitonin concentrations obtained with the two assays were similar for all patients except those with high procalcitonin levels. Among the patients, 12% (n=13) had basal calcitonin concentrations greater than 10 pg/ml with method A and 25.7% (n=25) with kit B. No correlation was found between calcitonin and procalcitonin concentrations. CONCLUSION: The new sensitive calcitonin assay tested is very efficient especially for the low concentrations. The cross-reaction for high procalcitonin levels exists and is variable according to the kits used. The procalcitonin evaluation can help the interpretation of ambiguous calcitonin levels.

Adolescent↗
PubMed2001

Lingual thyroid. A case report.

We describe an unusual clinical case in which a non functional cervical thyroid coexisted with a functional ectopic lingual thyroid. A twenty-year-old woman was referred for hypothyroidism treated with L-thyroxin related to a basilingual tumor diagnosed 8 years previously. Oropharyngeal examination showed a spherical basilingual tumor 2.5 cm in diameter. Laboratory findings during treatment with 50 microgram of L-thyroxin daily showed: TSH 6,280 microIU/ml (N: 4,4 to 3.6), FT3 4,2 pmol/l (N: 3.3 to 5.1), and FT4 15.4 pmol/l (N: 10,5 to 25,5). Antithyroid antibodies were absent. Cervical ultrasonography showed a small hypoechogenic, heterogeneous orthotopic thyroid gland confirmed by cervical computed tomography thyroid. An I(123) scan revealed uptake above the chin on the profile, and no significant uptake is the area of the normal thyroid. The lack of iodine uptake by the cervical thyroid remains unexplained. In conclusion, this report of an ectopic thyroid location in unusual because of the coexistence of non functional cervical thyroid and of a partially functional lingual thyroid tissue. The pathogenesis of this association remains unclear.

Adult↗
PubMed2000

Increased level of interferon-alpha in blood of patients with insulin-dependent diabetes mellitus: relationship with coxsackievirus B infection.

The activation of the interferon (IFN)-alpha system and its relationship with coxsackievirus B (CVB) infection has been analyzed in 56 patients with insulin-dependent diabetes mellitus (IDDM; 25 children and 31 adults). Elevated levels of IFN-alpha were found in plasma of 70% of patients (39/56), and a positive detection of IFN-alpha mRNA in blood cells by reverse transcriptase-polymerase chain reaction (RT-PCR) was observed in 75% of patients (42/56). Enterovirus (EV) RNA assayed by seminested RT-PCR was detected in the blood of 50% of IFN-alpha-positive patients but not in any IFN-alpha-negative patients. The results of genotype analysis of amplified EV RNA sequences (5 CVB2, 8 CVB3, and 8 CVB4) were concordant with the results of CVB-neutralization tests. The comparison between IFN-alpha, EV RNA, and serology suggested that the proportion of CVB infection associated with IFN-alpha positivity might be higher than is predicted from the investigation of EV RNA. Together, the results suggest that, in a majority of cases, a CVB infection is associated with clinical IDDM.

Adolescent↗