Biofilm prevalence and microbial characterisation in chronic wounds in a Sri Lankan cohort

Biofilms have been associated with chronic wound infections in diabetic patients. The study assessed the occurrence of biofilms in chronic diabetic wounds (CDWs) in a Sri Lankan cohort. Tissue specimens collected during surgical debridement were analysed by quantitative differential viable counting, scanning electron microscopy (SEM), fluorescence insitu hybridization (FISH) and light microscopy with Gram and Haematoxylin-Eosin staining. All specimens harboured >5·0 log₁₀ CFU per g bacteria and 2-9 distinct species per specimen were recovered from twenty wounds by culture. The most frequently isolated bacterium was Pseudomonas spp. (12/20;60%). Strict anaerobes were isolated from 10/20 specimens. Gram and Haematoxylin-Eosin staining showed aggregated micro-colonies, embedded in the wound tissue bed (20/20) but the exopolymer matrix was not visible in all samples (13/20). Fluorescence microscopy using a eubacteria-specific FISH probe indicated the presence of bacterial aggregates within the deep layers of the wound tissues (20/20). SEM revealed the presumptive architecture of matrix-embedded microbial clusters (20/20). The approximate diameter of bacterial aggregates in tissues ranged between 12 and 400 µm. Bacterial infiltration into the internal portions of the tissues was apparent using FISH, Gram, and Haematoxylin-Eosin staining. All CDWs carried biofilm-specific morphological features. FISH was more specific than SEM and indicated the presence of microcolonies within deeper tissues.

Prevalence of hypertension, diabetes and obesity: baseline findings of a population based survey in four provinces in Sri Lanka

OBJECTIVE

To determine the prevalence of selected cardiovascular risk factors in adult Sri Lankan population in four provinces.

DESIGN

Cross-sectional, based on a stratified cluster sampling method.

SETTINGS

Four provinces, namely the Western, North Central, Southern and Uva.

PATIENTS

Six thousand and forty seven participants (2692 men) between the age of 30 and 65 years were surveyed.

MEASUREMENTS

Risk factors measured included height, weight, waist and hip circumference. Waist to hip ratio and body mass index were calculated, and overweight (23 kg/m2) and obesity (> or = 25 kg/m2) determined. Hypertension (systolic blood pressure > or = 140 mmHg or diastolic blood pressure > or = 90 mmHg or use of anti-hypertensive medications), and diabetes mellitus (fasting serum plasma glucose level > or = 7 mmol/L or use of anti-diabetic medications) and impaired fasting glycaemia (> or = 6.1 to < 7 mmol/L) were also determined.

RESULTS

The prevalence of hypertension as defined was 18.8% (CI 14.5-23.1) for men and 19.3% (CI 12.2-26.4) for women. The prevalence of diabetes was 14.2% (CI 11.9-16.5) for men and 13.5% (CI 6.9-20.1) for women while impaired fasting glycaemia was 14.2% for men and 14.1% for women. The mean body mass index was 21.5 kg/m2 (SD = 3.7) in men. It was lower than that in women, 23.3 kg/m2 (SD = 4.5). The prevalence of obesity was 20.3% in men and 36.5 % in women. Regional differences were seen in the mean fasting blood glucose and prevalence of diabetes, and mean BMI and prevalence of obesity were highest in Western province. Mean blood pressure and prevalence of hypertension were highest in the Uva Province. Southern Province had the lowest prevalence of hypertension and diabetes, and North Central Province had lowest anthropometric measures of obesity.

CONCLUSIONS

The prevalence of the selected cardiovascular risk factors is common in the adult Sri Lankan population surveyed. Regional differences exist in the prevalence of these risk factors. The prevalence of high level of risk factors requires urgent public health action.