Differential distribution of IgA-protease genotypes in mucosal and invasive isolates of Haemophilus influenzae in Sweden

BACKGROUND: Several different IgA-proteases exist in Haemophilus influenzae. The variants have been suggested to play differential roles in pathogenesis, but there is limited information on their distribution in clinical isolates. The objective of this study was to investigate the distribution of IgA-protease genotypes in H. influenzae and assess the association between IgA-protease genotype and type of clinical infection. METHODS: We performed PCR-screening of the IgA-protease gene variants in two cohorts of clinical H. influenzae. The first cohort consisted of 177 isolates from individuals with respiratory tract infection in January 2010, 2011 and 2012. Information on age, gender and clinical infection was available in this cohort. The second cohort comprised 53 isolates, including NTHi from bloodstream, cerebrospinal fluid (CSF) and urogenital origin as well as encapsulated isolates respresenting all capsule types. We assessed associations between IgA protease genotype and clinical predictors using basic statistical tests of association as well as regression analysis. RESULTS: The igaB gene was found in 46% of isolates in the respiratory tract cohort, and no evident trend could be seen during the study years. However, the igaB gene was significantly less common among invasive isolates (19%), p = 0.003 (Fischer's exact test), even when encapsulated isolates were excluded (21%), p = 0.012. A significantly negative association between bacteraemia and igaB genotype remained after adjusting for covariates. We did not identify a significant association between IgA-protease gene variants and type of respiratory tract infection, but isolates with an igaA2 genotype were overrepresented in pre-school children. CONCLUSIONS: The distribution of IgA-protease gene variants in Swedish H. influenzae highlighted the widespread abundance of the igaB in isolates from cases of respiratory tract infection, but the igaB gene variant was significantly less common in invasive (bloodstream and CSF) isolates of H. influenzae compared with respiratory tract isolates

THE RELATIONSHIP BETWEEN SMOKING AND MICROVASCULAR COMPLICATIONS IN THE EURODIAB IDDM COMPLICATIONS STUDY

OBJECTIVE: To examine the relationship between smoking and both glycemic control and microvascular complications in patients with insulin-dependent diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS: This was a prevalence survey of 3,250 men and women aged 15-60 years with IDDM from 31 diabetes centers in 16 European countries. Participants completed a questionnaire, had retinal photographs taken, and performed a 24-h urine collection. HbA1c, frequency of hypoglycemic and ketoacidotic episodes, urinary albumin excretion rates, and retinopathy were compared by smoking category. RESULTS: The prevalence of smoking was 35% in men and 29% in women. Current smokers had poorer glycemic control and, among men, were more likely to have had a ketoacidotic episode than were those who never smoked. Ex-smokers had equivalent glycemic control and marginally more hypoglycemic episodes did than those who never smoked. Current smokers had a higher prevalence of microalbuminuria and total retinopathy than did those who never smoked. Ex-smokers had a higher prevalence of macroalbuminuria and proliferative retinopathy than did those who never smoked, but both had a similar prevalence of microalbuminuria. Adjustment for either current or long-term glycemic control could not fully account for these differences. CONCLUSIONS: Smoking is associated with poorer glycemic control and an increased prevalence of microvascular complications compared with not smoking. Ex-smokers can achieve glycemic control equivalent to and have a prevalence of early complications similar to that of those who never smoked. We suggest that poorer glycemic control can account for some of the increased risk of complications in smokers, and that quitting smoking would be effective in reducing the incidence of complications. Urgent action is required to reduce the high smoking rates in people with IDDM

BLOOD-PRESSURE, RETINOPATHY AND URINARY ALBUMIN EXCRETION IN IDDM - THE EURODIAB IDDM COMPLICATIONS STUDY

Several studies have shown an association between blood pressure and nephropathy, but few have been large enough to examine whether, or how, this relation is influenced by retinopathy. We have therefore examined the independent relations of blood pressure to urinary albumin excretion and retinopathy in a cross-sectional observational study of over 3000 insulin-dependent diabetic patients (the EURODIAB IDDM Complications Study). The relation of blood pressure to urinary albumin excretion differed strikingly between patients with (46%) and without (54%) retinopathy. In those with retinopathy, mean urinary albumin excretion rate was normal (<20 mu g/min) below median diastolic pressure (75 mmHg) and increased steeply (p < 0.001) with blood pressure above this level. However, in patients without retinopathy, mean albumin excretion rate was normal across the range of diastolic pressure. This finding could not be explained by differences in glycaemic control or duration of diabetes between patients with and without retinopathy. These data identify a subgroup of patients whose high risk of nephropathy may reflect abnormal renal vulnerability to mildly raised blood pressure. Retinopathy is a close correlate of this vulnerability. Detection of even mild retinopathy, together with raised blood pressure, may be important in assessing nephropathy risk

Cardiovascular disease and its risk factors in IDDM in Europe

OBJECTIVE - To study the prevalence of cardiovascular disease (CVD), its risk factors, and their associations in IDDM patients in different European countries. RESEARCH DESIGN AND METHODS - The prevalence of CVD (a past history or electrocardiogram abnormalities) and its risk factors were examined in a cross-sectional study in 3,250 IDDM patients from 16 European countries (EURODIAB IDDM Complications Study). The patients were examined in 31 centers and were stratified between centers for age, sex, and duration of diabetes. The mean +/- SD duration of diabetes was 14.7 +/- 9.3 years. RESULTS - The prevalence of CVD was 9% in men and 10% in women. The prevalence increased with age (from 6% in patients 15-29 years old to 25% in patients 45-59 years old) and with duration of diabetes. The between-center variation for the whole population was from ? to 19%. In both sexes, Easting triglyceride concentration was higher and HDL cholesterol lower in those patients with CVD than in those without. In men, duration oi diabetes was longer, waist-to-hip ratio greater, and hypertension more common in patients with CVD. In women, a greater BMI was associated with increased prevalence of CVD. There was no association between insulin dose, HbA(1c) level, age-adjusted rate of albumin excretion, or smoking status and CVD. Waist-to-hip ratio, particularly in men, was positively associated with age, age-adjusted HbA(1c), prevalence of smoking, daily insulin dose, albumin excretion rate, and fasting triglyceride concentrations. CONCLUSIONS - The overall prevalence of CVD in these IDDM patients was similar to 10%, increasing with age and duration of diabetes and with a sixfold variation between different European centers. CVD prevalence was most strongly associated with elevated triglyceride and decreased HDL cholesterol concentrations. CVD was also associated with albuminuria, but when adjusted by age, this association vanished. Increasing waist-to-hip ratio was associated with a number of adverse characteristics, particularly in IDDM men, reflecting the metabolic syndrome previously described in other populations