The aerobic bacteriology of infected skin lesions in children of the Eastern Highlands Province.

Of 480 children studied, the relative frequency of skin infections divided into three categories were: score 266 (55%), infected scabies 164 (34%) and tropical ulcers 50 (10%). Infected scabies was more prevalent in the less than 2 year age group and tropical ulcers were commonest in the 9-12 year age group and these differences were significant. The majority of lesions occurred on the lower extremities with the trunk the least commonly affected area. No significant differences were found in different age groups between males and females. Beta haemolytic streptococci (95%), Staphylococcus aureus (83%), Corynebacterium diphtheriae (72%) and Corynebacterium haemolyticum (35%) were the major bacteria isolated. Beta haemolytic streptococci were the most prevalent in infected scabies and least in tropical ulcers and these differences were significant. Three major Lancefield groups were isolated: group A (61%), group C (19%) and group G (19%). The distribution of these groups were unequal with group A most common in infected scabies but rarely seen in tropical ulcers. Groups C and G were found more commonly in tropical ulcers than the other two groups of lesions and these differences were significant. Multiple populations of beta haemolytic streptococci in a single lesion were seen in 19% of children. Less than one third of Streptococcus pyogenes were M typable and of these 18% were known nephritogenic serotypes. Staphylococcus aureus was significantly more common in infected scabies and least common in tropical ulcers. The prevalence of Vincent's organisms in tropical ulcers (74%) was significantly higher than scores (9%) and infected scabies (1%). The isolation rate of Corynebacterium diphtheriae was significantly higher in infected scabies than the other two groups. The most common biotype isolated was var mitis (72%). Only 2% of isolates were toxigenic. Corynebacterium haemolyticum was isolated significantly more frequently in tropical ulcers than the other lesions. All major bacteria, excluding betalactamase-producing Straphylococcus aureus, were uniformly sensitive to penicillin. Methicillin resistance was found in 1% of Staphylococcus aureus isolates and is reported here for the first time in this country. These isolates were also multiply resistant to erythromycin, chloramphenicol and tetracycline.