Search PubMed⌕ Search

Biomedical subjects

D Seal

Publications and source records attributed to D Seal.

32 records · Page 2Linked to original sources
PubMed1989

Staphylococcal infection and the limbus: study of the cell-mediated immune response.

The relationship between enhanced cell-mediated immunity (CMI) to staphylococcal antigens, expressed as delayed hypersensitivity (DH), and the development of catarrhal infiltrates at the limbus in the rabbit has been explored by others. This DH is required for infiltrates to develop in the rabbit cornea when it is exposed to conjunctival inoculation with live Staphylococcus aureus cells. Similar investigations have not been pursued in the human, although St. aureus has been isolated from lids of patients with sterile marginal ulcers. We have tested 69 patients with blepharitis, eleven with and 58 without associated symptomatic marginal keratitis, for DH to killed whole cells of St. aureus and St. epidermidis and protein A; quantitative cultures have also been collected from lids and conjunctivae. Preliminary findings show that nine out of 11 patients with symptomatic marginal keratitis, requiring treatment with steroids, have enhanced DH to St. aureus cell wall antigens. We suggest the hypothesis that this type of marginal keratitis in the human is the result of enhanced CMI at the limbus to St. aureus cell wall antigens.

Adult↗
PubMed1988

The paradox of using a 7 day antibacterial course to treat urinary tract infections in the community.

1. We have studied determinants of outcome of 7 day courses of treatment in 77 middle aged and elderly patients, in whom the general practitioner's diagnosis of urinary tract infections had been confirmed microbiologically. Bacteria were sensitive to cephalexin or trimethoprim. Where there was no preference, treatments were allocated randomly. Compliance was monitored using a pill box with a concealed electronic device which recorded openings of the box. 2. Prescribing trimethoprim, 200 mg twice daily, was more effective than cephalexin, 250 mg four times daily (cure rates 93 and 67%) (P less than 0.006). Those cured and not cured were not distinguished by age, gender, genitourinary history, or infecting organism. 3. Compliance as measured by box openings was worse for cephalexin than for trimethopim (P = 0.01). However, both totality and pattern of compliance were similar in patients cured and not cured by cephalexin. Thus rigid adherence to a conventional course did not promote cure: fewer doses could have been prescribed. 4. Estimating compliance is essential to clinical trials where medication is self-administered. Poor compliance may establish over exacting regimens. Counting box openings did overestimate compliance, but counting residual tablets overestimated it grossly: given the number of openings less than the ideal, there should have been 171 residual tablets, only 55 were found.

Aged↗
PubMed1987

Treatment of relapsing Clostridium difficile diarrhoea by administration of a non-toxigenic strain.

Two patients with relapsing Clostridium difficile diarrhoea following metronidazole and vancomycin therapy were colonised with a non-toxigenic avirulent Clostridium difficile strain given orally in three doses. Both patients appeared to respond without side-effects. Oral bacteriotherapy with a defined nontoxigenic strain of Clostridium difficile would appear to represent an acceptable, alternative and novel way to treat hospitalised patients who relapse with Clostridium difficile diarrhoea after specific antibiotic therapy.

Aged↗
PubMed1985

Diarrhoea due to enterotoxigenic Clostridium perfringens: clinical features and management of a cluster of ten cases.

Clostridium perfringens has recently been shown to be associated with antibiotic-associated diarrhoea. We describe here the clinical features and management of an outbreak of diarrhoea in a Geriatric Unit. Ten cases were due to enterotoxigenic C. perfringens and in these cases there was a highly significant correlation with recent antibiotic administration (P = 0.0001). The importance of early recognition of C. perfringens as a cause of infective diarrhoea in the elderly is stressed.

Aged↗
PubMedDate not supplied

Microbial keratitis in Hong Kong: relationship to climate, environment and contact-lens disinfection.

Microbial keratitis has been studied in Hong Kong as a representative sub-tropical climate of south China. An 18-month investigation in 1997/98 of 223 cases of ulcerative keratitis (presumed microbial) was conducted in the 2 million population of Shatin and Kowloon at the Prince of Wales and Hong Kong Eye Hospitals respectively with comprehensive microbiology. A case-control study was pursued at the same time between 45 contact-lens wearers (CLW) developing microbial keratitis and 135 lens-wearing volunteers matched for age, sex, educational status and visual acuity. Home water supplies were sampled for Acanthamoeba. Previous ocular surface disease and trauma (preventable by wearing goggles for grinding) were common predisposing causes while cosmetic wear of contact lenses was responsible for 26% of cases overall. Pseudomonas aeruginosa was the commonest bacterium isolated, from both CLW and non-CLW, with infection being acquired within the community. These 28 pseudomonads remained fully sensitive to the third-generation cephalosporins, aminoglycosides and quinolone antibiotics, which is very encouraging. Fungi were isolated, predominantly Fusarium sp., but less commonly than expected. A fungal/bacterial ratio was obtained of 1/17, while in comparison, the expected ratio for a tropical climate ranges from 1/5 (Singapore) to 1/2 (South India). Acanthamoeba was the second commonest microbe isolated from keratitis of CLW. The domestic water environment of 8% of homes of both patients and controls wearing contact lenses was colonized with Acanthamoeba. Lack of hygiene, use of tap water for storing lenses, failure to air-dry lens-storage cases or use of one-step hydrogen peroxide disinfectant were identified as risk factors for keratitis in CLW. The study results commend use of multipurpose solutions by CLW in Hong Kong to achieve the lowest expected rates of infection.

Acanthamoeba Keratitis↗