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B A Dudding

Publications and source records attributed to B A Dudding.

24 records · Page 2Linked to original sources

The role of normal skin in the spread of streptococcal pyoderma.

The primary body site of acquisition of group A streptococci was examined prospectively in a population with endemic streptococcal pyoderma. Weekly cultures were obtained during the skin infection season from apparently normal upper respiratory and cutaneous sites (and from skin lesions when present) in 44 children and adults living on the Red Lake Indian Reservation.During the 9-week period of the study 705 of a total of 2305 cultures were positive for group A streptococci. The percentage of positive cultures from the various sites were: throat (20%); nose (24%); wrist (32%); ankle (35%); back (22%); and skin lesions (81%). Group A streptococci were also isolated from fingernail dirt, clothing and bedding as well as from a few household pets and insects.Analysis of serial cultures obtained from the same individuals at weekly intervals suggested that the strains isolated from skin lesions first appeared on normal skin in the 2 weeks preceding the lesion. Spread to the nose and throat followed skin acquisition and/or skin lesions.The high prevalence of group A streptococci on normal skin in the absence as well as the presence of pyoderma, and their appearance on normal skin before recovery from either skin lesions or the upper respiratory tract are consistent with the view that skin acquisition was a primary predisposing factor to pyoderma. Since the literature indicates that group A streptococci are rarely part of the normal skin flora, these findings raise the possibility of unique biological properties of these and perhaps other pyoderma strains, as distinct from other group A streptococci.

Adolescent↗

Persistence of streptococcal group A antibody in patients with rheumatic valvular disease.

Antibody levels to streptococcal Group A and A-variant carbohydrates were determined using a radioactive immune precipitation technique on patients with rheumatic fever, with and without valvular disease, on patients with post-streptococcal acute glomerulonephritis, and on age-matched controls. During the acute phase of the above illness, the means of the antibody levels to both carbohydrate antigens were equally elevated and were significantly higher than the normal controls. When Group A antibody levels were determined on sera obtained at intervals of 5-12 months and 1-5 yr after the acute illness) it was found that the antibody levels declined within the normal range at the 5-12 month interval in patients with glomerulonephritis as well as in patients with rheumatic fever in whom no valvular involvement had complicated the disease, i.e., patients with pure Sydenham's chorea. However, in patients with rheumatic valvulitis, who had been on penicillin prophylaxis after the last acute episode, the A antibody level showed little decline from the level obtained during the acute illness. The elevated antibody level in patients with rheumatic valvulitis, including patients with Sydenham's chorea with valvulitis, persisted for periods of at least 1 yr and up to 20 yr after the last acute attack. The pattern of the decline of the antibody levels to the A-variant carbohydrate as well as of the antibody titers to the other streptococcal antigens tested, ASO and anti-DNase B, was similar in all patients studied regardless of the presence of valvular disease. These findings suggest that prolonged persistence of the Group A antibody is a phenomenon peculiar to patients with rheumatic valvular disease. Whether this persistence is involved in the pathogenesis or is an outcome of the valvular disease remains to be determined.

Acute Disease↗