Störungen der Glukosetoleranz bei Thalassaemia major

Background. In patients suffering from thalassemia major, hemosiderosis frequently causes endocrine disorders. We investigated the development of glucose tolerance disorders and the influence of therapeutical interventions such as intensified chelation therapy and diet. Methods and patients. 60 patients with thalassemia major, ages ranging from 4 to 36 years, treated regularly with both subcutaneous desferrioxamine infusions and erythrocyte transfusions, were investigated for endocrine disorders. Oral and intravenous glucose tolerance tests as well as intravenous glucagon challenge were used to investigate the insulin secretion. In patients with impaired glucose tolerance the influence of intensified (intravenous) chelation therapy and dietary interventions on blood glucose and serum insulin levels were studied. Results. In patients with thalassemia major, disturbed glucose tolerance appears to be one of the four most common endocrine disorders in the second decade of life and later. In the early stages of the disease, glucose tolerance disorders were associated with hyperinsulinemia; in later stages insulinopenic diabetes develops due to β-cell exhaustion. In some patients in the early stages of the disease, intensified chelation therapy or dietary treatment only improved their glucose tolerance. Conclusion. Especially for thalassemia patients in the early stages of glucose tolerance disorders, intensified desferrioxamine treatment and diet can be of benefit and in some cases retard the manifestation of diabetes mellitus. These treatments do not, however, change the requirement for insulin substitution at an advanced stage of disturbed glucose tolerance.     

Glucose homeostasis in mucoviscidosis

In patients with cystic fibrosis (CF) of the pancreas an endocrine imbalance especially of insulin secretion due to progressive structural abnormalities of the pancreas must be expected. 30-75 percent of CF-patient exhibit impaired oral glucose tolerance tests (oGTT). Deterioration of the glucose homeostasis leads to a secondary diabetes mellitus that mimics a type II diabetes in the early stage, in the later course of disease it resembles a type I diabetes with absolute insulinopenia. In this study glucose homeostasis was investigated after an oral glucose load with 1.75 g glucose/kg bodyweight. Glucose, C-peptide and insulin were measured during 180 minutes. 32 nondiabetic CF-patients were studied. 16 patients revealed an impaired oral glucose tolerance according to the criteria of the National Diabetes Data Group. 6 patients showed a normal glucose tolerance and 10 patients with normal fasting and 120 minute glucose concentrations were hyperglycemic at midtest determinations. Impaired oGTTs were observed in malnourished CF-patients in a higher rate than in normal weight patients. A delayed and exceeded C-peptide and insulin response to the oral glucose load was determined with deteriorating glucose tolerance. Glucose values did not drop to fasting values at the 180 minute determination in cases of impaired oral glucose tolerance.     

Glucose tolerance in cystic fibrosis.

Glucose tolerance was evaluated in 356 living and dead patients with cystic fibrosis who were recorded at the Danish Cystic Fibrosis Centre. Twenty two patients (6%) were treated elsewhere, 25 (7%) were unable, unwilling or too young (age less than 2 years) to participate; 309 patients (87%) were therefore eligible for the study of whom 99 (32%) were dead and 210 (68%) were alive. Of the dead patients, 13 also had diabetes mellitus (13%). Of the living patients (median age 14 years, range 2-40), nine (4%) were known to have diabetes and all were being treated with insulin. In the remaining 201 patients an oral glucose tolerance test (1.75 g/kg body weight, maximum 75 g) was carried out. A total of 155 patients (74%) had normal glucose tolerance, 31 (15%) had impaired glucose tolerance, and 15 (7%) had diabetes mellitus according to the WHO criteria. The percentage of glycated haemoglobin (HbA1c) (reference range 4.1-6.4%) increased significantly as glucose tolerance decreased: when glucose tolerance was normal the median was 5.2%; when it was impaired the figure was 5.5%; in patients whose diabetes was diagnosed by the oral glucose tolerance test it was 5.9%; and in patients already known to have diabetes mellitus it was 8.6%. The incidence and prevalence of impaired glucose tolerance and diabetes mellitus increased with age. From the age of 15 to 30 years the decrease in the prevalence of normal glucose tolerance was almost linear. Within this age span the proportion of patients with cystic fibrosis with normal glucose tolerance was reduced by roughly 5%/year. Only 35% (95% confidence interval (CI) 22 to 48%) of the patients with cystic fibrosis who were alive at the age of 25 years had normal glucose tolerance; 32% (95% CI 14 to 49%) were diabetic. The prevalence of glucose intolerance in cystic fibrosis is rapidly increasing with age; its potentially harmful effect on the prognosis of cystic fibrosis is of increasing importance as the length of survival of these patients increases.     

Glucose intolerance and diabetes during cystic fibrosis

As a result of the improvement in life-expectancy in cystic fibrosis patients, simultaneous presence of cystic fibrosis and diabetes mellitus is no longer exceptional. In teenagers and young adults with cystic fibrosis, the prevalence of insulin-dependent diabetes mellitus (IDDM) is 7 to 10%. Fifty percent of cystic fibrosis patients have impaired glucose tolerance. These prevalences increase with advancing age. Insulin deficiency is a consistent feature. An endocrine pancreatic deficiency thus exists in addition to the exocrine pancreatic deficiency, as demonstrated by the fall in glucagon and pancreatic polypeptide productions. Development of insulin dependency is associated with deterioration in clinical status and indicates an adverse prognosis. Although in cystic fibrosis patients diabetes mellitus seems to occur as a result of different pathophysiologic mechanisms than those involved in autoimmune IDDM, the risk of degenerative complications is similar in both conditions. It follows that early detection of diabetes mellitus and appropriate insulin treatment are warranted in cystic fibrosis patients.     

Prävalenz von Ketoazidosen bei Manifestation des Diabetes mellitus Typ 1 in einem Zentrum für pädiatrische Diabetologie

Introduction. Diabetic ketoacidosis (DKA) is still the most serious complication of the newly diagnosed child with diabetes mellitus type 1 because it is still the most common cause of death due to cerebral edema. Methods. All patient records of children with new diagnosed type 1 diabetes mellitus in the children's hospital of the University of Leipzig in 1995 to 1999 were analysed retrospectively. Results. 31 patients (29,8%) had DKA, 10 of which were unconscious or somnolent. In those children and adolescents with DKA blood glucose levels, glycosylated hemoglobin levels and initial insulin requirement were higher and the duration of hospital stay was longer. The rate of remission was lower in the DKA group (67 vs. 80.8%). A delayed or false diagnosis was reported in 14% of patients without but in 22,5% of the children and adolescents with DKA. Conclusion. To improve the rate of remission and reduce the hospital stay at the onset of diabetes mellitus the rate of DKA must be reduced due to better information about symptoms of diabetes mellitus in the general population and especially among general practitioners and pediatricians.     

Assoziation von Mukoviszidose, Zöliakie und heterozygotem α-1-Antitrypsin-Mangel bei einem Kleinkind

Background. Cystic fibrosis associated diseases as coeliac disease or α-1-antitrypsin deficiency may remain undetected for a long time, as the leading symptoms may be explained by the underlying basic disorder CF. Case report. We report on a 4 year old caucasian cystic fibrosis patient with additional α-1-antitrypsin deficiency and coeliac disease. If a patient with cystic fibrosis fails to thrive despite intensive treatment, additional disorders, for example coeliac disease, must be excluded by means of serology and histology. An α-1-antitrysin deficiency syndrom in cystic fibrosis patients with hepatic manifestation may accelerate the progression of liver cirrhosis and increase the risk of acquiring pseudomonas aeruginosa.     

Hypoglykämien mit neurologischen Komplikationen bei Kindern mit Typ-1-Diabetes im Vorschulalter

Rationale. Preschool children with type 1 diabetes have a high incidence of severe hypoglycemia with convulsions or loss of consciousness. Prevention of severe hypoglycemias is a preeminent goal in the long-term care of diabetic children. Methods. Twenty-four preschool children with diabetes (age ≤6 yrs) were prospectively studied for 12 months. Incidence of severe hypoglycemic episodes and neurologic symptoms were registered and related to diabetes control and therapy. Severe hypoglycemia was defined as blood glucose below 60 mg/dl and severe neurologic signs (convulsions, loss of consciousness, paresis). Results. Five episodes of severe hypoglycemia occurred in 5 out of 24 preschool children (incidence 0.21/yr). Major signs were generalized convulsions (2 patients), focal convulsion without loss of consciousness (2 patients) and isolated transient hemiparesis in 1 patient. All episodes occurred at night between 11.30 p. m. and 4.20 a. m.. Causes identified in retrospect were an inadequately high basal insulin dose at bedtime in 4 children and an insufficient reduction of insulin after increased physical activity in one child. In the 5 children with severe hypoglycemia BMI was significantly (p = 0.015) higher in the 5 children with severe hypoglycemia compared with those without severe hypoglycemias. Age, duration of diabetes, average HbA1c levels, daily insulin dose, number of insulin injections and number of blood glucose tests were not different. Conclusions. All episodes of severe hypoglycemias in preschool children occurred at night between 11.30 p. m. and 4.20 a. m. The most likely cause was too much basal insulin at bedtime. Families with young diabetic children should be alert to the danger of high insulin doses at bedtime and the necessity of early dose reductions. A high body mass index was associated with the occurrence of severe hypoglycemia, while a low HbA1c value by itself was not.     

Oral glucose tolerance testing in cystic fibrosis: Correlations with clinical parameters and glycosylated haemoglobin determinations

In 48 patients (age 2–28 years) with documented cystic fibrosis, glucose tolerance was evaluated by means of an oral glucose tolerance test (OGTT) and repeated glycosylated haemoglobin (HbA1C) measurements. An impaired OGTT was found in 15 patients. Their degree of undernutrition and severity of lung and liver involvement were no different from those with normal glucose tolerance. The mean peak insulin concentration as well as the integrated insulin concentration during the OGTT were comparable with patients with normal glucose tolerance (GT) and those with an impaired tolerance (GI). The mean time to attain peak insulin levels was significantly delayed in the GI group. (117 min vs 86 minP<0.01). On initial testing, elevated HbA1C levels were found in 22 patients. Mean HbA1C levels in the GI group were higher than in the GT group *8.2% vs 7.5%P<0.01). The HbA1C levels at the moment of OGT testing were positively correlated with the glycaemic response during the OGTT. The repeated HbA1C measurements 1 year later were no different from the initial mean HbA1C values in both groups. Two GI patients with initial HbA1C levels of 7.5% and 11% respectively developed diabetes mellitus several months after testing. The need for serial HbA1C determinations in cystic fibrosis is questioned.     

Mitochondriopathie bei einem Kind mit Shwachman-Syndrom und Zöliakie Fallbericht

Background. The Shwachman syndrome represents one of the causes of exocrine pancreatic insufficiency, surpassed in incidence only by cystic fibrosis. It is a heriditary multi-organ disease with effects on pancreatic function, hematopoesis and growth of cartilage and bone. Case report. In our case, who presented with a rare combination of celiac disease and diabetes mellitus, we want to emphasise the large variability of clinical signs and symptoms. The pathogenesis of Shwachman syndrome is not delineated. The case presented here showed a respiratory-chain-defect in complex II, IV and V in fibroblast culture. Conclusions. We propose patients with Shwachman syndrome to investigate for respiratory-chain defect. This could help for better classification and diagnosis of this syndrome.     

Prävalenz und Altersverteilung des Diabetes mellitus im Kindesalter in Deutschland

Aim. Our main objective was to estimate the prevalence of diabetes mellitus among children aged 0–14 years in Germany on the basis of the incidence surveys done between 1987 and 1998 in Baden-Wuerttemberg. Methods. Data were collected from the pediatric divisions of hospitals in the state (n = 31) as well as from one hospital specializing in diabetes. Results. The mean incidence of diabetes mellitus type 1 among children aged 0–14 years was 12.9/100,000/year (95% CI 12.37–13.37) for the period covering 1987 to 1998. The prevalence among children aged 0–14 years in Baden-Wuerttemberg was up to December 31, 1998, 0.082% (95% CI 0.078–0.086). Average age at the time of diagnosis was 8.7 years among boys and 8.6 years among girls. Conclusions. It is possible to extrapolate the incidence of diabetes mellitus for Germany as a whole on the basis of the results from Baden-Wuerttemberg. Calculations done accordingly show that the total number of diabetic children in the Federal Republic is 11,000 for children aged 0–14 years. Such estimates are fundamental for the further development of medical infrastructures in the field of pediatric diabetes.     

Research of factors for glucose intolerance in mucoviscidosis]

Glucose tolerance has been assessed in cystic fibrosis (CF) children using HbA1C and plasma glucose and insulin determinations during an oral glucose tolerance test (OGTT), along with the determination of HLA-DR and islet-cell (ICA) and anti-insulin (IAA) antibodies. Of 49 patients (25 males, 24 females), aged 2 to 21 years (mean = 10.9 years), 29 had normal glucose tolerance (WHO criteria) during OGTT, 14 had impaired glucose tolerance (IGT) and 6 had an isolated hyperglycemia at 120 min. Fasting plasma glucose and HbA1C were significantly higher in IGT than in normoglycemic patients. However, these two parameters showed poor individual predictive value of disturbance in glucose tolerance. Of 14 patients with abnormal OGTT, 7 were aged below 10 years, with 2 as young as 5 years; 8 patients were females. HLA antigens characteristic of type I diabetes tended to be found less frequently in CF patients than in the general population: 9% were DR3, 7% were DR4 and none was DR3/DR4. There were no HLA differences according to glucose tolerance. ICA and IAA were respectively detected in only one patient. Stimulated plasma insulin was low but did not correlate with glucose tolerance. In conclusion, impaired glucose tolerance is common in cystic fibrosis and can be found early in life. Although insulin secretion is decreased in this population, it does not seem to be the only factor responsible for impaired glucose intolerance. The absence of the genetical and immunological characteristics of type I diabetes confirms that glucose intolerance in cystic fibrosis is due to other pathogenetic mechanisms.     

Insulin resistance is associated with decreased clinical status in cystic fibrosis

Patients with cystic fibrosis (CF) frequently have impaired glucose tolerance and progression to diabetes (DM) with clinical features of both insulin-dependent and non-insulin-dependent diabetes. One feature of non-insulin-dependent DM is decreased insulin sensitivity, also known as insulin resistance. The goal of this study was to determine whether patients with CF exhibit insulin resistance and to determine the potential effect of insulin resistance on clinical status. We also sought to determine whether insulin resistance is associated with a specific CF genotype. We studied 18 patients with CF (8 with normal glucose tolerance, 5 with impaired glucose tolerance, 5 with DM), and 20 lean control subjects matched for age, weight, and sex. All control subjects had normal glucose tolerance. The clinical status for each CF patient was determined according to a modified National Institutes of Health scoring system. Each subject underwent a three-step hyperinsulinemic euglycemic clamp (insulin doses of 10, 40, 120 mU/m ² per minute). Results from the 120 mU/m ² per minute infusion defined maximal glucose disposal rate (defined in milligrams per kilogram body weight per minute) at steady state with peripheral insulin levels 195 ± 20 mU/ml. Subjects with CF demonstrated insulin resistance (control subjects = 13.6 ± 1.1, patients with CF = 10.2 ± 1.6 mg/kg per minute; p = 0.003). When each subgroup was compared separately with control subjects, all subgroups were statistically insulin resistant (glucose disposal rate, patients with CF and normal glucose tolerance = 10.8; those with impaired glucose tolerance = 8.4; those with DM = 10.1 mg/kg per minute), and the patients with CF with impaired glucose tolerance were the most insulin resistant. When plotted versus glucose disposal rate, a striking positive correlation between worsened clinical status and insulin resistance ( r = 0.85) is demonstrated. Furthermore, there is no correlation between insulin resistance and fasting blood glucose, subject age, or percent ideal body weight (all r values not significant). In conclusion, patients with CF exhibit insulin resistance that is associated with worsened clinical status. We believe it is the combination of insulin resistance and decreased insulin secretion that is responsible for the high incidence of CF-related diabetes. (J Pediatr 1997;130:948-56)     

Reduced pancreatic insulin release and reduced peripheral insulin sensitivity contribute to hyperglycaemia in cystic fibrosis

Traditional opinion holds that patients with cystic fibrosis (CF) develop impaired glucose tolerance or diabetes due to insulinopenia caused by fibrosis of the pancreas. However, studies on the dynamics of insulin secretion and peripheral insulin action have yielded confliciting results. We studied 18 patients with CF (9 , 9 , age 15–29 years) and 17 healthy control subjects (8 , 9 , 20–32 years). Oral glucose tolerance tests and combined i.v.-glucose-tolbutamide-tests were performed on separate days in fasting subjects. Bergman's Minimal Model was used to quantitate both peripheral insulin sensitivity (S_I) and insulin-independent glucose disposal (glucose effectiveness; S_G). Based on National Diabetes Data Group criteria, 4 patients were classified as diabetic 922%; CF-DM), 3 patients (17%) had impaired glucose tolerance (CF-IGT) while glucose metabolism was normal in 11 patients (61%; CF-NGT). Irrespective of the degree of glucose tolerance, the insulin response to oral glucose was not reduced but delayed, up to 60 min in the CF-IGT/DM group. First-phase insulin release (0–10 min) after i.v.-glucose was significantly lower in CF patients (29% of healthy controls;P<0.0001), with no difference between the CF-NGT and CF-IGT/DM groups. Insulin release following tolbutamide injection was only marginally reduced in CF patients (64% of controls). In contrast, S_I was significantly reduced in the subgroup of CF patients with abnormal glucose metabolism (CF-IGT/DM: 0.97±0.16·10^–4 l/min/pmol; control group: 1.95±0.25;P<0.05).Conclusion The early insulin release is reduced in response to i.v.-glucose, while in the oral glucose tolerance test, insulin secretion is quantitatively preserved, but delayed. Reduced peripheral insulin sensitivity is a major factor for impaired glucose tolerance and diabetes mellitus in CF patients.     

Glucose intolerance in cystic fibrosis patients

Diabetes mellitus has evolved as a complication because of increased longevity of patients with cystic fibrosis (CF). CF-related diabetes (CFRD) is associated with increased morbidity and mortality, therefore, prompt diagnosis and aggressive management are important.The prevalence of CFRD increases with age with an age-dependent incidence rate of 5% per year; at 30 years 50% of patients are diabetic. CFRD develops insidiously. Screening by measurements of fasting, random plasma glucose or glycated haemoglobin A(1c), alone or in combination, do not reliably identify CFRD as compared with the 2-hour plasma glucose value measured during an oral glucose tolerance test.Reasons for the development of CFRD are not fully understood. Generally, patients are characterised by the presence of a class I, II or III CF mutation, exocrine pancreatic insufficiency, impaired and delayed insulin secretion, impaired glucagon secretion, normal insulin sensitivity and an increased insulin clearance rate. One can speculate that for endocrine dysfunction to deteriorate from normal to impaired glucose tolerance and then to CFRD, there must be an additional diabetes mellitus-related genetic defect.CFRD leads to deterioration of overall clinical CF status but insulin therapy can revert this. Late diabetic complications may develop as in other types of diabetes although macrovascular complications are rare. CFRD patients have an increased mortality compared to non-diabetic CF patients. Insulin therapy is the preferred treatment.     

Carbohydrate metabolism changes in cystic fibrosis

AIMS: To assess the prevalence of impaired glucose tolerance (ITG) and diabetes mellitus (DMRCF) in a group of patients with cystic fibrosis (CF). To study clinical status-related variables and to compare age with the evolution of their carbohydrate metabolism (CHM). PATIENTS AND METHODS: Thirty patients with CF (1.5-26 years). Oral glucose tolerance test (OGTT) in 28 patients. RESULTS: Three patients (10%) showed ITG and four DMRCF (13.3%). CF patients with impaired CHM (ICHM) were older (p = 0.006), and had longer times since diagnosis and first sputum colonization (p = 0.001, p < 0.001). Homozygous deltaF508 mutation was significant (p = 0.001). Insulin peak, area under the curve for insulin, insulin resistance, insulin sensitivity, and pancreatic beta-cell function were all significant. CONCLUSIONS: ICHM was present in 23.3%. Age, time since diagnosis of CF, first sputum colonization and homozygous deltaF508 mutation were significantly associated. CHM in patients with CF is similar to that in the population without CF in the early years.     

Insulin sensitivity and beta-cell secretion in thalassaemia major with secondary haemochromatosis: assessment by oral glucose tolerance test

Diabetes mellitus in patients with thalassaemia major is caused by secondary haemochromatosis due to transfusional iron overload. The pathogenetic mechanisms leading from siderosis to diabetes are still poorly understood. This study aimed at assessing the influence of insulin resistance and insulin deficiency on that process. Glucose, insulin and C-peptide levels during oral glucose tolerance tests (OGTT) from 36 thalassaemic patients with normal ( n=23), impaired ( n=6), or diabetic glucose tolerance ( n=7) and 32 control subjects were examined. Insulin secretion and insulin sensitivity were assessed by established calculated indices. Fasting, 2h and integrated glucose concentration were significantly increased in thalassaemic patients with normal glucose tolerance compared to controls (5.01/4.59 mmol/l, 6.33/5.17 mmol/l, and 844.2/739.3 mmol/l per min, respectively; all P<0.03). Patients with impaired glucose tolerance presented hyperinsulinaemia and delayed peak insulin during OGTT. The C-peptide/insulin ratio was decreased in patients with abnormal glucose tolerance compared to controls (5.85/7.33 x 10(3)pmol/l per min, P<0.03). It was negatively correlated with age in patients ( r=-0.45, P<0.01), but positively in controls ( r=0.43, P<0.03). Insulin sensitivity was significantly reduced in patients with impaired glucose tolerance or diabetes compared to controls. In addition, a significant decrease in patients with normal glucose tolerance was shown by two insulin sensitivity indices (all P<0.05). In thalassaemia patients, insulin sensitivity was negatively correlated with age. Insulin secretion capacity according to the homeostasis assessment model was significantly reduced in patient groups compared to controls (Kruskal-Wallis-test, P<0.004). CONCLUSION: Insulin resistance is of central importance for the development of diabetes mellitus in patients with secondary haemochromatosis. An additional early defect in beta-cell secretion cannot be excluded.     

Insulin improves clinical status of patients with cystic-fibrosis-related diabetes mellitus

Cystic-fibrosis-related diabetes mellitus is frequently underdiagnosed and associated with deterioration of overall clinical status. The purpose of this prospective study was to investigate the influence of insulin on nutrition, lung function and clinical status of cystic fibrosis patients. For a period of 5 y, and at 6-mo intervals, body mass index, forced expiratory volume in 1 sec, Shwachman score, intravenous glucose tolerance test and first-phase insulin response were determined in 30 cystic fibrosis patients (age range 10-35 y) with exocrine pancreatic insufficiency. During the study period, six patients (3M and 3F; age range 15-22 y) developed diabetes and required insulin therapy. The decrease of first-phase insulin response coincided with deterioration of nutritional and clinical status, which improved significantly 6 mo after the institution of insulin. CONCLUSION: Insulin, as an anabolic hormone, could have an influence on body mass, which may affect pulmonary function and clinical condition in cystic fibrosis. It is important to identify cystic fibrosis individuals at risk of developing diabetes so that early insulin therapy is instituted.     

Diabetes mellitus in Danish cystic fibrosis patients: prevalence and late diabetic complications

Lanng S, Thorsteinsson B, Lund-Andersen C, Nerup J, Schiatz PO, Koch C. Diabetes mellitus in Danish cystic fibrosis patients: prevalence and late diabetic complications. Acta Pzdiatr 1994;83: 72–7. Stockholm. ISSN 0803–5253.
The prevalences of impaired glucose tolerance (IGT), diabetes mellitus and late diabetic complications were studied in all Danish cystic fibrosis (CF) patients. A total of 311 CF patients were identified with an estimated ascertainment rate above 98%. Glucose tolerdnce was classified in 278 (89%) patients: the prevalences of IGT and diabetes mellitus were 13.7% (38 patients) and 14.7% (41 patients), respectively, with no sex differences. The prevalence of diabetes mellitus increased with age but not with the severity of CF as compared with age- and sex-matched non-diabetic CF patients. Diabetes was diagnosed at a median age of 20 years (range 3–40 years) and the duration of diabetes was 1.7 years (0.1–17 years). Twenty-eight of the diabetic patients (70%) were trcated with insulin, on average 20 (4–90) IU per day. Late diabetic complications were identified in 4 patients (10%) with a duration of diabetes mellitus of 1–17 years: background retinopathy (2 patients), diabetic nephropathy (1 patient), microalbuminuria (1 patient) and neuropathy (2 patients). Thus diabetic CF patients are probably not less prone to develop late diabetic complications than patients with other types of diabetes of equally long duration and comparable glycemic control.     

Metformin zur Behandlung des primär nicht insulinpflichtigen Diabetes mellitus bei adipösen Jugendlichen Bericht über 3 Fälle

Background. Metformin has proven efficacy in the treatment of obese adults with type-2 (non-insulin-dependent) diabetes mellitus. Case reports. We report in retrospect on three overweight adolescents with non-insulin-dependent diabetes mellitus, who were treated by hypocaloric diet plus metformin. During 10–14 months of follow -up, HbA1c transiently fell from 9.6–12.0% to 5.1–5.9%, while obesity persisted. In two patients (one with Prader-Willi-syndrome), body weight and HbA1c-levels increased again. Discussion. In summary, the cases provide further evidence for the efficacy of metformin in children and adolescents with non-insulin-dependent diabetes mellitus (e. g. type-2 diabetes). Caution,however, is required with this approach, as type-2 diabetes is the exception in childhood diabetes, and metformin should, therefore, be applied not as first-line treatment in childhood diabetes. Successful weight reduction appears to be of outmost importance for sustaining good metabolic control in obese adolescents with type-2 diabetes.     

Endocrine pancreas function in mucoviscidosis

Patients with cystic fibrosis of the pancreas show an incidence of diabetes mellitus tenfold higher than is found in the general pediatric population. Considering this fact glucagon and insulin responses to oral glucose and intravenous arginine were studied in 22 CF children and adolescents. Some investigated patients had suffered from the disease for ten years and more. On the one hand the results show that pancreatic alpha cell function is normal. The kinetics of endogenous glucagon release are unaltered. On the other hand the data reveal that there is only a defect in the beta cell function consisting in a delayed insulin release selective to glucose whereas responsiveness to other stimuli for example tolbutamide and arginine is undisturbed. Furthermore there is a diminution in insulin-output to oral glucose as well as to intravenous arginine. Yet in patients with normal oral glucose tolerance endogenous insulin secretion is significantly reduced. Their regular carbohydrate tolerance may be a function of the patient's ability to maintain increased receptor numbers in the face of hypoinsulinemia. Despite greater quantities of secreted hormone a degree of relative peripheral insulin insensitivity has developed in the presence of hyperglycemia. This may be a consequence of impaired affinity of the specific target cell receptors. The insulin secretion pattern is proven to be identical to that of chemical diabetes mellitus in adults. Quantitative diminution in arginine stimulated insulin-output has been found to be independent of the degree of carbohydrate intolerance.(ABSTRACT TRUNCATED AT 250 WORDS)