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Biomedical subjects

P J Stevens

Publications and source records attributed to P J Stevens.

At least 19 recordsLinked to original sources
PubMed1992

High level gentamicin resistance in enterococcal and streptococcal isolates from blood culture.

The combination of an aminoglycoside with a cell wall active agent is often necessary for the satisfactory management of serious enterococcal and streptococcal infections. High level gentamicin resistance (MIC > 1000 micrograms/ml) eradicates the synergy between these two classes of antibiotics and treatment of these infections becomes difficult. Over a four year period we assessed the susceptibility of blood culture isolates of enterococci, Streptococcus agalactiae (group B), and clinically significant viridans-type streptococci. The susceptibility of the organisms to gentamicin could be determined utilizing high content aminoglycoside discs. We report an increasing prevalence of high level gentamicin resistance in enterococci in South London, with 44% of isolates being resistant in the first quarter of 1991. None of the streptococcal isolates demonstrated high level gentamicin resistance. We recommend screening for high level gentamicin resistance in all enterococcal and streptococcal cases where aminoglycoside-penicillin synergy is desired.

Drug Resistance, Microbial↗
PubMed1991

Serological investigation of ocular toxoplasmosis.

The limitations of serological assessment in toxoplasma infection of the eye are well recognised, but the predictive value of clinical examination is not defined. We undertook a prospective investigation into the role of clinical examination and of serological findings in cases of suspected toxoplasma infection of the eye by means of the dye test and multiple IgM assays. Seventy-four cases of retinal disease and 202 control patients were studied. Patients with retinal disease had a significantly higher incidence of toxoplasma seropositivity than the control group. This was because some patients with retinal disease had acquired the infection congenitally. Half the patients investigated for toxoplasmosis were seronegative. Possible explanations for these findings included misdiagnosis, clinical uncertainty, or, the use of serology testing in the confirmation of other diseases. An excess of IgM reactivity among the retinal disease group may indicate low level immunoglobulin-M production associated with an acute exacerbation of ocular toxoplasmosis. There is a need to consider invasive procedures in cases of ocular infection and for novel techniques to aid the diagnosis of toxoplasma retinochoroiditis.

Adolescent↗
PubMed1990

A new approach to the management of malignant ascites; a permanently implanted abdominal drain.

A new approach to the problem of intractable malignant ascites in preterminal abdominal carcinoma is presented. Seventeen patients treated with a new implantable silastic drain are described. Symptomatic relief was excellent in all patients for as long as the drain was patent. Complications included abdominal wall cellulitis in two instances and one case of peritonitis, but did not preclude continued drain function in 15 of the 17 cases. In eight of the 17 cases organisms were cultured from the ascitic fluid while the catheter was in situ. Drainage of ascitic fluid in this way appears to be a practical management for intractable malignant ascites.

Abdomen↗
PubMed1989

Prevalence and susceptibility of highly gentamicin resistant Enterococcus faecalis in a south London teaching hospital.

Combinations of aminoglycosides plus ampicillin usually are necessary for the satisfactory management of serious Enterococcus faecalis sepsis. A study in a South London hospital demonstrated that 7% of all E. faecalis, and 30% of those from blood cultures, were highly gentamicin resistant. Addition of gentamicin confers no benefit to the treatment of these organisms with ampicillin. We looked at the susceptibility pattern of these organisms in vitro and concluded that ampicillin plus ciprofloxacin offered the best available combination.

Anti-Bacterial Agents↗
PubMed1988

Epidermolysis bullosa letalis: an immunogenetic disease of extraembryonic ectoderm?

A newborn male infant with epidermolysis bullosa letalis died at age 6 weeks of septicemia. He had many congenital ectodermal abnormalities and a rudimentary thymus. The spleen had no germinal centers and the lymph nodes lacked follicles. Cytotrophoblast of the amniochorion was sparse and the amniotic epithelium was distorted. Immunohistologic studies of amniotic epithelium revealed the unprecedented presence of trophoblast antigens. Before birth of the patient, the parents had a 5-year history of infertility; after death of the patient, the mother sustained a ruptured tubal pregnancy that necessitated blood transfusions and surgical removal of the tube. She subsequently became pregnant a third time and was delivered of a normal child. The wife shared four major histocompatibility (HLA) antigens with her husband. The parents' immunogenetic characteristics and the immunopathologic features and extraembryonic membranes of the child are considered in terms of maternal responses to trophoblast antigens.

Amnion↗
PubMed1987

Evaluation of a preentrance enrichment program for minority students admitted to medical school.

The authors report on an enrichment program for minority students and its effect on those students' performance in the first year of medical school. The six-week preentrance enrichment program (PEP) offers a curriculum of basic science courses, study skills training, and a seminar on special topics, typically on sociomedical issues. From 1973 through 1984, 115 students who had been admitted to Boston University School of Medicine participated in the PEP prior to matriculation. The PEP participants had lower scores on the Medical College Admission Test than minority nonparticipants admitted to the medical school. Analysis of the first-year performance of PEP participants, however, indicated that the participants had significantly higher proportions of pass and honors grades than minority nonparticipants in two courses and slightly higher (though not significant) proportions of pass and honors grades in six other courses of the nine courses in the first-year curriculum. In a related study, preliminary analysis showed that participation in the PEP was one of the consistent predictors of overall academic performance during the first year. Questionnaires completed by participants before and after the program and their responses to a survey at the end of their first year of medical school indicated the participants felt they had gained benefits from the program that enhanced their academic adjustment.

Boston↗
PubMed1986

Raising a colostomy--results of a prospective surgical audit.

A prospective surgical audit of all colostomies fashioned over a 1-year period in one hospital was conducted. Of one hundred and ten colostomies there were 56 loop and 52 end stomas. Following the formation of the colostomy a proforma was completed and the surgeon interviewed to document the precise surgical technique employed. Whilst in hospital the patients were regularly reviewed and the colostomies assessed by a surgeon and stomatherapist using a scoring system. Follow up was continued until closure of the colostomy or for a minimum period of 1 year. Only 53 (48%) of patients saw a stomatherapist preoperatively. This rate was higher in elective (86%) than in urgent cases (15%). The surgial technique used did not appear to influence the outcome of any given colostomy. However, failure to cruciate the posterior rectus sheath may predispose to stomal stenosis and the use of a subcutaneous polyethylene rod to support a loop colostomy often led to infection. Tension of the colostomy led to complications in 29 cases (26%), this was often the precipitating event to other complications and led to the only colostomy-related death. Registrars with experience of fewer than 5 colostomies received their training largely from other registrars rather than consultants. This prospective surgical audit has disclosed that fashioning a colostomy carries significant stoma related morbidity, most of which is potentially avoidable. Appropriate audit can contribute to the maintenance and improvement of surgical standards.

Colostomy↗
PubMed1984

Metastatic basal cell carcinoma. Report of five cases and review of 170 cases in the literature.

We report five cases of metastasizing basal cell carcinoma. The incidence of metastases in all patients with basal cell carcinomas who had surgery in the same period was 0.1%. There was no squamous differentiation in the histology of any of the primary lesions, but we found some squamous differentiation in a late recurrence in one patient and in the metastases in two patients. All other histologic features were identical in both the primary tumor and in the metastases. Perineural spread and blood vessel invasion were evident in the primary tumor and/or recurrence of three of the five patients and may be important pointers to possible recurrence and metastasis. Of 205 cases of metastasizing basal cell carcinomas mentioned in the literature, we accepted and evaluated 170 cases of tumors of the skin with histologic proof of metastasis. The male-to-female ratio was 2:1, median age at onset of primary tumor, 45 years, median interval between onset of tumor and first sign of metastasis, 9 years, median age at first sign of metastasis, 59 years, and median survival after first sign of metastasis, only 8 months. The site of the primary tumors is similar to that in nonmetastasizing basal cell carcinoma. Metastatic spread is most often to lymph nodes, lungs, and bones with lymphogenic and hematogenic spread equally frequent. Age or sex of the patient seemed to have no influence on survival or way of metastatic spread. As metastasis of basal cell carcinoma is extremely rare (1 in 1,000 to 35,000), many authors sought or postulated histologic "degeneration" into a squamous cell carcinoma, but no such unequivocal evidence has ever been found. Areas of squamous differentiation were reported in less than 15% of both primary and metastatic lesions of metastasizing basal cell carcinoma. The mode of metastatic spread and the characteristics of the histology make it rather unlikely that metastasis of a basal cell carcinoma is due to a change toward squamous cell carcinoma.

Adult↗
PubMed1980

Transferrin and transferrin receptors in carcinoma of the breast.

Breast tissues from 59 patients were immunohistologically studied for transferrin and transferrin receptors. None of the 8 normal breasts or 22 benign mastopathies, and only 1 of 7 fibroadenomas were reactive for transferrin, but 16 (72.7%) of 22 carcinomas were positive and parallel sections showed histopathologically that the rective areas were confined to tumour-cell membranes. That breast-tumour transferrin is probably receptor-bound in vivo was indicatd by its complete chemical removal in vitro and return to the same cells following reincubation with dilute solutions of transferrin. Similar bindig is found on certain normal or transformed cells and at the maternofetal interface of human placentae. It is suggested that this oncofetal receptor preferentially binds apotransferrin and may offer a novel approach to more specific therapy of certain breast cancers.

Breast↗
PubMed1980

Human amnion as an adjunct in wound healing.

Biopsy specimens from the beds of leg ulcers of fifteen patients were obtained before and after the application for 5 days of cultured human amnion. After amnion application there was considerable granulation tissue in the ulcer bed and microscopical evidence of thinned connective tissues, vessel development, more compact resolution of vascular basement membranes, and many more factor VIII granules within endothelial cells. These findings suggest the presence of angiogenic factors in human amnion and this could explain the hitherto unexplained success of amniotic membranes in surgical practice.

Amnion↗
PubMed1979

Management of the perineal wound with constant irrigation and suction after abdominoperineal excision for cancer of the rectum. A new suction/irrigation drain.

The technique of primary closure of the perineal wound combined with continuous irrigation and suction of the operative site has been used in 21 patients who underwent abdominoperineal excision for cancer of the rectum or anal canal. Primary healing occurred in 19 patients within 18 days, and all patients healed within 2 months. These results are in marked contrast to those in 38 patients treated with constant suction alone, of whom only 17 healed primarily.

Anus Neoplasms↗
PubMed1977

A suggested method of preparation of the large bowel for investigation and surgery.

A safe, effective method of large-bowel preparation is outlined, the emphasis being on a standardized technique for the average patient. The rationale for the use of the technique is briefly described, and there is a further section on the preparation of the bowel in a patient with a colostomy. The importance of a residue-free fluid diet and adequate saline purgation is stressed.

Anti-Bacterial Agents↗
PubMed1976

The temporary colostomy.

The indications for a temporary transverse colostomy are examined in the light of a year's experience of the Stomatherapy Service at Groote Schuur Hospital. A surgical technique, which employs primary colocutaneous suture and which may be used in both emergency and elective situations, is described.

Abdomen↗