Beta-cell autoantibodies and diabetes mellitus family history in cystic fibrosis

OBJECTIVE: To verify whether autoimmunity against beta-cells and family history of type 1 and/or type 2 diabetes mellitus (DM) play a role in the pathogenesis of cystic fibrosis (CF)-related diabetes mellitus (CFRD). PATIENTS AND METHODS: The prevalence of beta-cell autoantibodies (GADA and IA-2A) was investigated in a group of patients with CF compared with patients with type 1 DM (DM1) and controls. Family history of DM1 and/or DM2 was investigated among patients with CF. RESULTS: Frequency of beta-cell autoantibodies was significantly lower (p = 0.0001) in patients with CF with CFRD (IA-2A: 0%; GADA 12.5%) than in patients with DM1 (64.1% vs 52.8%, respectively) and it did not differ from the frequency in patients with CF without CFRD. Prevalence of family history for DM1 or DM2 was not significantly higher in CF patients with CFRD than in CF patients without CFRD. CONCLUSIONS: The investigated factors did not show correlation with the pathogenesis of CFRD.     

Thyroid hormones and thyroglobulin autoantibodies in insulin dependent diabetes mellitus

Serum T4, FT4, T3, and TSH were measured in a group of children with insulin dependent diabetes mellitus and a control group. In the insulin dependent diabetes mellitus group, serum T3 concentration was significantly lower than the control values. Serum T4, FT4 and TSH level did not differ. The difference in serum T3 concentration was significant between diabetic children with good or poor control. Thyroglobulin antibodies were investigated in diabetic children by Serono's "hTg antibodies" kit. Thyroglobulin antibodies were present in 14.5%. TSH concentration did not differ in antibody positive and negative cases, but one child with diabetes had evidence of moderately impaired thyroid reserve.     

Contrasting features of insulin dependent diabetes mellitus associated with neuroectodermal defects and classical insulin dependent diabetes mellitus

The Wolfram, or DIDMOAD, syndrome is a rare congenital disease that is associated with diabetes insipidus, insulin dependent diabetes mellitus of an early onset, bilateral optic atrophy and deafness. Urological disorders are usually present as well. We have studied nine patients belonging to five different families. All of the family members were HLA typed (including DR), and islet cell as well as antinuclear antibody determinations were carried out. Although individuals with insulin dependent diabetes mellitus are very prone to have either HLA-DR3 or -DR4 antigens, none of our patients had DR3 antigens and only one was DR4 positive. On the other hand, three of our patients were typed as HLA-DR2 positive. This antigen is uncommon in classical insulin dependent diabetes. In one of the families, the affected siblings did not share the same HLA haplotype. Islet cell and antinuclear antibodies were not found in any of the cases and six of the patients had a small, but significant, insulin secretory reserve. On the basis of some of the clinical features it was also possible to further distinguish between the DIDMOAD syndrome and the classical insulin dependent diabetes mellitus. The differences encountered between classical and DIDMOAD insulin dependent diabetes mellitus--the presence/absence of HLA linkage, HLA-DR2, -DR3 and -DR4 associations, islet cell or antinuclear antibodies, the tendency to ketosis and diabetic retinopathy--indicate that their etiopathogenies are triggered by distinct mechanisms.     

Residual insulin secretion in insulin dependent diabetes mellitus.

The residual insulin secretory capacity of 244 children with insulin dependent diabetes mellitus was determined by measurement of their 24 hour urinary C peptide excretion. An inverse linear relation was found between the residual B cell secretion and the duration of diabetes. The age at onset of diabetes did not affect the residual B cell function significantly.     

Leptin levels in children with insulin dependent diabetes mellitus

Leptin, a product of the ob gene, is a polypeptide hormone produced in adipose tissue that informs the brain about the amount of energy storage of body fat. It has very important effects on neuroendocrine functions and energy expenditure. The aim of our study was to determine leptin levels of children with insulin dependent diabetes mellitus (IDDM), which is known to affect body metabolism, and to investigate the relationship between duration of the disease, insulin dosage, HbA1c levels, body mass index (BMI), serum lipids and IGF-1 levels. Sixteen patients with IDDM (chronological age 13.8 +/- 2.6 years) whose HbAlc levels were 10.2 +/- 1.9 %, BMI 21.2. +/- 2.7 kg/m2, insulin dosage 0.9 +/- 0.4 U/kg/day and duration of the disease 6.7 +/- 2.6 years, and 12 healthy controls (13.4 +/- 2.6 years) were included in the study. Fasting plasma leptin levels were measured by radioimmunoassay method. The mean plasma leptin levels of the patient and the control groups were 19.1 +/- 7.6 ng/ml and 6.1 +/- 2.9 ng/ml, respectively, and significant difference was found between the two groups (p < 0.05). No correlation was found between leptin values and IGF-1, cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride levels, atherogenic index, insulin dosage or HbA1c levels in the patient group. A weak statistical correlation was determined between BMI and leptin levels in the IDDM group (r = 0.28, p < 0.05). A positive correlation was also found between leptin levels and the duration of the disease (r = 49, p < 0.05). As a result, it seems that leptin levels of children with IDDM differed from the levels of the control group significantly, and that the duration of insulin therapy was responsible for this difference.     

Pre-HbA1c in children with insulin dependent diabetes mellitus

Day-to-day fluctuations in blood concentration of the glycosylated hemoglobin, HbA1c or HbA1, are mainly due to variations in content of the intermediate aldimide form, preHbA1c. Using electrofocusing we have studied this component adjacent to the HbA1c band, which represents the stable ketoamine form. The fraction of preHbA1c present rapidly increases upon incubation of erythrocytes in 20 mM glucose at +37 degrees C, and the reaction is fully reversible if glucose is removed. In children with insulin-dependent diabetes mellitus with different degrees of metabolic control, levels of preHbA1c varied between 0.2 and 3.7% of total hemoglobin (median value 1.3%, N = 25). A clear correlation was found between preHbA1c and urinary glucose concentrations during the 12 hours preceding blood sampling (r = 0.75, p less than 0.001, df = 18). As expected, pre-HbA1c did not correlate to HbA1c or glycosylated albumin, which reflect long- and medium-term diabetic control.     

Autonomic dysfunction and severe hypoglycaemia in insulin dependent diabetes mellitus.

The aims of the present study were to investigate the relationship between severe hypoglycaemia and autonomic dysfunction in diabetic children, and to assess the glycaemic response to an insulin infusion test. In a one year period, 12 of 69 diabetic patients (17%) experienced at least one severe episode of hypoglycaemia, defined as an event which required outside assistance. All patients underwent five cardiovascular autonomic tests. Seven of the hypoglycaemic patients showed three or more abnormal autonomic tests. Among the 57 non-hypoglycaemic diabetics, there was no patient with three or more abnormal tests. In hypoglycaemic diabetics with and without autonomic dysfunction, and in eight healthy age matched subjects an insulin infusion test was performed. A pronounced blood glucose decline and a subnormal increase in heart rate during insulin infusion were obtained in patients with autonomic dysfunction. Thus, severe hypoglycaemia may be due to impaired defence mechanisms against blood glucose decline in diabetic children with autonomic dysfunction.     

Helicobacter pylori infection in children with insulin dependent diabetes mellitus

To assess the seroprevalence of Helicobacter pylori (HP) in children with insulin dependent diabetes mellitus, a serological test for Helicobacter pylori (anti-HP IgG with ELISA) was performed in 88 diabetic and 42 healthy control children. Anti-HP IgG was positive in 49/88 (55.6%) of diabetics and 13/42 (30.9%) of controls (p<0.01). Diabetic children were divided into two groups according to HP status: HP(+) and HP(-). The two groups were compared for age, gender, duration of diabetes, diabetic control (HbA1c), SDS for height and gastric emptying time. Seroprevalence of HP was higher in IDDM patients than in healthy controls. Duration of diabetes was the only factor which correlated significantly with HP status. HP status was not related to gastric emptying time.     

Incidence of insulin dependent diabetes mellitus in Karachi, Pakistan

OBJECTIVES: To determine the incidence of insulin dependent diabetes mellitus (IDDM) among children aged up to 16 years residing in the city of Karachi, Pakistan, during the five years from 1989 to 1993. DESIGN: Retrospective study of incidence using hospital and clinic records. SETTING: The city of Karachi, Pakistan. SUBJECTS: Children satisfying standard criteria for the diagnosis of IDDM, attending treatment facilities for the first time during the study period. MAIN OUTCOME MEASURES: The incidence of IDDM in this population and its variation by age and sex. RESULTS: The incidence of IDDM in this population is 1.02/100000 per year, which is one of the lowest incidence rates yet reported. CONCLUSIONS: The very low incidence of IDDM, contrasted with the substantially higher incidence among migrants, supports the view that environmental factors are the major determinants of variations in the incidence of this condition between populations.     

Child abuse suspicion masquerading new onset insulin dependent diabetes mellitus

The identification and diagnosis of child abuse is a challenging task to the pediatrician. The increased awareness among both the public and medical personnel, while improving attentiveness to this important subject, can sometimes result in misdiagnosing medical conditions, thus causing distress and delay in required treatment. Numerous reports have described conditions mimicking non-accidental injuries; most of these include dermatological findings related to skin diseases, medical conditions causing pathological fractures, and rare diseases with unusual physical findings. We present a case of a 9.5-year-old child in which the workup for a suspected abusive event led to a delay in the diagnosis of insulin dependent diabetes mellitus later presented as diabetic ketoacidosis.     

Nocturnal hypoglycaemia and sleep disturbances in young teenagers with insulin dependent diabetes mellitus

OBJECTIVE: To determine the effect of nocturnal hypoglycaemia on sleep architecture in adolescents with insulin dependent diabetes mellitus (IDDM). DESIGN: 20 adolescents with IDDM (mean age 12.8 years, mean glycated haemoglobin (HbA1c) 8.9%) were studied on one night. Plasma glucose was measured every 30 minutes and cortisol and growth hormone levels every 60 minutes. Sleep was recorded using standard polysomnographic montages, and sleep architecture was analysed for total sleep time, stages 1-4, rapid eye movement, fragmentation, and arousals. RESULTS: Six subjects (30%) became hypoglycaemic (five subjects < 2.5 mmol/l), with one being symptomatic. There were no differences in age, HbA1c, duration of diabetes, or insulin regimen between hypoglycaemic and non-hypoglycaemic subjects. Hypoglycaemia was not predicted by glucose measurements before bed. There was no detectable rise in plasma cortisol or growth hormone concentrations during hypoglycaemia. Sleep architecture was not disturbed by nocturnal hypoglycaemia with no differences found in sleep stages, fragmentation, or arousals. CONCLUSIONS: Nocturnal hypoglycaemia is a common and usually asymptomatic complication of treatment in adolescents with IDDM. Moderate hypoglycaemia has not been shown to affect sleep architecture adversely. These findings are consistent with, and may explain, the observation that severe hypoglycaemia, with consequent seizure activity, is more common at night than during the day. Counterregulatory hormone responses to nocturnal hypoglycaemia may be less marked than with similar degrees of diurnal hypoglycaemia.     

Urinary C-peptide excretion at onset of insulin dependent diabetes mellitus in children

The 24-hour urinary excretion of C-peptide and the plasma C-peptide concentration were measured at the onset of insulin dependent diabetes mellitus (IDDM) in children. The excretion of C-peptide was twice as high as that found in normal control subjects, whereas the plasma C-peptide values were markedly lower, indicating increased urinary leakage of C-peptide in this phase of the disease. In the diabetic children under seven years of age the mean value of C-peptide excretion was clearly lower than in the older children.     

Diabetes mellitus in cystic fibrosis: effect of insulin therapy on lung function and infections

The effect of insulin therapy on lung function and lung infections was studied in a retrospective case-control design in 18 diabetic cystic fibrosis (CF) patients; 18 non-diabetic CF patients, matched for sex, age and presence of chronic Pseudomonas aeruginosa lung infection. served as controls. Parameters of CF clinical status were collected for six years before and two years after the onset of insulin therapy in the diabetic patients. Before onset of insulin therapy, body mass index (BMI) and forced vital capacity (FVC) in (pre)diabetic patients deviated increasingly from those in control patients. Decreases in BMI and lung function during the past three months before onset of insulin therapy were reverted within three months of insulin therapy. From three months to two years after onset of insulin therapy, differences in BMI and lung function diminished between diabetic and control patients. After two years of insulin therapy, BMI was similar in diabetic and non-diabetic patients and the percentage differences in forced expiratory volume in 1s (FEV₁) and FVC between the two groups were similar to those found six years before the onset of insulin therapy. The finding that insulin therapy improves lung function in diabetic CF patients suggests strongly that the insidious decline in lung function seen during the years before the diagnosis of diabetes mellitus results from the pre-diabetic condition. After onset of insulin therapy, the percentages of sputum examinations positive for Haemophilus infuenzae and Streptococcus pneumoniae decreased in the diabetic patients, whereas parameters of lung infections with P. aeruginosa and Staphylococcus aureus remained unchanged. In conclusion, since insulin therapy improves lung function and reduces the number of infections with H. influenzae and S. pneumoniae in diabetic CF patients, we suggest that insulin therapy should be started when diabetes mellitus is diagnosed.