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D Taylor-Robinson

Publications and source records attributed to D Taylor-Robinson.

At least 145 records · Page 8Linked to original sources
PubMed1993

Evaluation of sensitivity of 10 diagnostic assays for Chlamydia trachomatis by use of a simple laboratory procedure.

AIMS: To determine the sensitivity of commercially available diagnostic assays for Chlamydia trachomatis using a simple method. METHODS: Nine commercial assays and an "in-house" polymerase chain reaction (PCR) were evaluated using serial dilutions of a laboratory grown H serovar--four of them using a laboratory grown E serovar. Seven of the assays were further tested using dilutions of several cervical samples known to contain chlamydiae. RESULTS: The most sensitive assays were the MicroTrak direct fluorescent antibody (DFA) test (Syva) and the PCR which detected C trachomatis at a 10(-8) dilution of the H serovar, while the two least sensitive, Clearview (Unipath) and TestPack (Abbott), were positive only at 10(-4) and 10(-3) dilutions, respectively. A range of enzyme immunoassays (EIAs) and a nucleic acid hybridisation test were of intermediate sensitivity. The results with serovar E were consistent with these. When clinical samples were examined, the DFA test detected C trachomatis in dilutions at least 10-fold greater than any other assay. CONCLUSIONS: The range of sensitivity of diagnostic assays determined by the laboratory dilution procedure is very wide. Sensitivity assessed in this way, however, reflects the ability of the assays to detect C trachomatis in large scale clinical trials. The dilution procedure, which is simple to undertake, could therefore be applied by any laboratory before a new diagnostic method is considered for routine use.

Chlamydia Infections↗
PubMed1993

Evaluation of sensitivity of 10 diagnostic assays for Chlamydia trachomatis by use of a simple laboratory procedure.

AIMS: To determine the sensitivity of commercially available diagnostic assays for Chlamydia trachomatis using a simple method. METHODS: Nine commercial assays and an "in-house" polymerase chain reaction (PCR) were evaluated using serial dilutions of a laboratory grown H serovar--four of them using a laboratory grown E serovar. Seven of the assays were further tested using dilutions of several cervical samples known to contain chlamydiae. RESULTS: The most sensitive assays were the MicroTrak direct fluorescent antibody (DFA) test (Syva) and the PCR which detected C trachomatis at a 10(-8) dilution of the H serovar, while the two least sensitive, Clearview (Unipath) and TestPack (Abbott), were positive only at 10(-4) and-3 dilutions, respectively. A range of enzyme immunoassays (EIAs) and a nucleic acid hybridisation test were of intermediate sensitivity. The results with serovar E were consistent with these. When clinical samples were examined, the DFA test detected C trachomatis in dilutions at least 10-fold greater than any other assay. CONCLUSIONS: The range of sensitivity of diagnostic assays determined by the laboratory dilution procedure is very wide. Sensitivity assessed in this way, however, reflects the ability of the assays to detect C trachomatis in large scale clinical trials. The dilution procedure, which is simple to undertake, could therefore be applied by any laboratory before a new diagnostic method is considered for routine use.

Bacteriological Techniques↗
PubMed1993

Human papillomavirus DNA in the urogenital tracts of men with gonorrhoea, penile warts or genital dermatoses.

OBJECTIVE: To assess the presence of human papillomavirus (HPV) DNA in urethral and urine specimens from men with and without sexually transmitted diseases. DESIGN: Prospective study. SETTING: Two London departments of genitourinary medicine PATIENTS: 100 men with urethral gonorrhoea, 31 men with penile warts and 37 men with genital dermatoses. METHODS: Urethral and urine specimens were taken, HPV DNA extracted and then amplified using the polymerase chain reaction. HPV types 6, 11, 16, 18, 31 and 33 were identified using Southern blotting followed by hybridisation. RESULTS: HPV DNA was detected in 18-31% of urethral swab specimens and in 0-14% of urine specimens. Men with penile warts had HPV detected in urethral swabs more often than did men in the other two clinical groups. "High risk" HPV types were found in 71-83% of swab specimens and in 73-80% of urine specimens containing HPV DNA. CONCLUSIONS: HPV is present in the urogenital tracts of men with gonorrhoea, penile warts and with genital dermatoses. In men with urethral gonorrhoea, detection of HPV in urethral specimens is not related to the number of sexual partners, condom usage, racial origin or past history of genital warts. HPV DNA in the urethral swab and urine specimens may represent different aspects of the epidemiology of HPV in the male genital tract. The preponderance of HPV types 16 and 18 in all three groups of men may be relevant to the concept of the "high risk male".

Adolescent↗
PubMed1993

Clinical features and management of recurrent balanitis; association with atopy and genital washing.

OBJECTIVE: To evaluate clinical features and diagnostic investigations in patients with recurrent or unresponsive balanitis in order to institute rational management. DESIGN: Forty-three patients presenting to a genitourinary medicine clinic with recurrent or persistent balanitis were studied. All patients were asked whether they had a history of atopic illness and about their practice of genital washing. All patients were investigated by taking a swab specimen from the preputial area for bacterial and viral culture and 30 underwent biopsy of the affected skin. Follow-up was between three and six months. SETTING: Outpatient genitourinary medicine clinic, St Mary's Hospital, London, UK. RESULTS: In 31 (72%) of the patients a diagnosis of irritant dermatitis was made. In comparison with the remaining patients, they had a greater lifetime incidence of atopic illness and more frequent daily genital washing with soap. For 28 (90%) of these patients, use of emollient creams and restriction of soap washing alone controlled symptoms satisfactorily. For the remaining 12 patients, a variety of diagnoses were made. Biopsy proved a well tolerated and diagnostic investigation, but the isolation of microbial pathogens from preputial swabs was irrelevant to management. CONCLUSION: A history of atopic illness and of the practice of penile washing are important aspects in the evaluation of patients with recurrent balanitis. Biopsy is an important investigation in the condition when it does not seem to be caused by irritant dermatitis.

Adult↗
PubMed1993

Changes in HPV infection in patients with anogenital warts and their partners.

OBJECTIVES--To investigate the relationship between clinical findings and the detection of human papillomavirus (HPV) DNA in a range of anatomical sites in patients with and without anogenital warts. SUBJECTS--Men and women with a clinical diagnosis of anogenital warts, or a current partner with anogenital warts. SETTING--A department of genitourinary medicine in central London. METHODS--The anogenital areas of the patients were thoroughly examined using a colposcope before and after application of acetic acid. Different types of specimens were taken from a variety of anatomical sites. Superficial skin sampling was performed by the application of slides covered with "Superglue" (SG) to clinically normal and abnormal areas of anogenital skin. The presence of human cells in the SG samples was confirmed by detection of the beta-globin gene using the polymerase chain reaction (PCR). HPV DNA was extracted from the specimens and amplified by using consensus primers with the PCR. HPV types 6, 11, 16, 18, 31 and 33 were identified by Southern blotting followed by hybridisation. RESULTS--In women, HPV DNA was detected in 83% of wart biopsies, 29% of cervical biopsies, 36% of cervical scrapes, 25% of urethral loop specimens, 37% of vaginal washes and 33% of rectal swab specimens. In men, HPV DNA was detected in 67% of wart biopsies, 37% of urethral loop specimens and 12% of rectal swab specimens. Of the SG samples containing the beta-globin gene, 49% from women and 50% from men contained HPV DNA. HPV DNA was not detected in buccal scrapes and serum samples from women or men. Of all specimens with detectable HPV DNA, there was evidence of a single HPV type in 41%, multiple types in 48% and undetermined types in 11%. Samples taken from different sites of a patient tended to have HPV types in common. Sexual partners, however, did not consistently have HPV types in common. CONCLUSIONS--HPV DNA was distributed widely in the anogenital area, in warts, acetowhite areas and clinically normal skin. The SG technique was well tolerated by patients and produced results consistent with other findings. Sampling from a single site of the genitalia on one occasion may significantly underestimate the infection rate with HPV. Multifocal infection of the anogenital area with HPV should be taken into consideration when interpreting epidemiological studies and management strategies.

Adolescent↗
PubMed1993

Identification and preliminary characterization of a cytotoxin isolated from Mobiluncus spp.

Mobiluncus curtisii and M. mulieris are anaerobic curved rods commonly isolated, together with other bacteria, from the vagina of women with bacterial vaginosis (BV). We have shown that of 11 strains of M. curtisii and four strains of M. mulieris examined, each produced a cytotoxin after growth in three types of liquid media. The toxin present in supernatant fluids after centrifugation of Mobiluncus cultures was active against Vero cells and four other cell lines tested, producing a marked cytopathic effect with destruction within 72 hours. The supernatant fluids could be diluted no more than 8 to 16-fold before toxic activity was lost. In bovine oviduct organ cultures, the supernatant fluids from cultures of eight M. curtisii and two M. mulieris strains that were tested caused loss of ciliary vigour which was usually complete after 60 hours. In addition, there was raggedness of the epithelial cell border with detachment of cells seen histologically and loss of cilia together with bloating and loss of ciliated cells observed by scanning electron microscopy. The toxin was extracellular, relatively thermostable (surviving heating to 56 degrees C for 30 min but not boiling for 20 min) and was inactivated under extremes of pH (pH 9 and pH 3). The existence of the toxin means that the Mobiluncus spp could have an active role in the development of BV.

Animals↗
PubMed1993

Factors influencing the ability of different mycoplasmas to colonize the genital tract of hormone-treated female mice.

Colonization of the genital tract of female mice, mainly BALB/c, by Mycoplasma genitalium, M. pneumoniae and M. pulmonis was enhanced by pretreatment of the mice with progesterone. M. fermentans, M. hominis and M. salivarium, and three serotypes and two untyped strains of Ureaplasma urealyticum colonized under the influence of oestradiol but not progesterone. Mycoplasmas dependent on progesterone were glucose-metabolizing, with strong haemadsorptive and other attachment properties, and possessed a terminal structure. Mycoplasmas dependent on oestradiol were arginine or arginine/glucose metabolizing. Ureaplasmas also required oestradiol. The oestradiol-requiring group appeared to be less cytadsorptive and devoid of a morphological terminal structure. Mycoplasmas that had had multiple passes in media were less able to colonize. This may be one, but not the only, reason for the failure of seven mycoplasmas to colonize under the influence of either hormone. The observations suggest the existence of a receptor mechanism for colonization, progesterone-requiring mycoplasmas being exposed to, and needing, genital tract cells different from those exposed to oestradiol-requiring mycoplasmas.

Animals↗
PubMed1992

Detection of Chlamydia trachomatis DNA in joints of reactive arthritis patients by polymerase chain reaction.

In 1986, Chlamydia trachomatis elementary bodies were found by direct immunofluorescence (DIF) in synovial-fluid cell deposits and synovial-membrane biopsy samples from five of eight patients with sexually acquired reactive arthritis (SARA) but in none of eight controls with other types of arthritis. Cells from the original slides (stored at 4 degrees C) have now been examined by a polymerase chain reaction (PCR) that amplifies DNA for the major outer membrane protein of C trachomatis. Chlamydial DNA was found in samples from four DIF-positive patients, one DIF-negative patient, and one DIF-negative control. Overall, there was 80% concordance for DIF and PCR results. This study supports our previous finding of chlamydiae in joints in reactive arthritis.

Adult↗
PubMed1992

A longitudinal study of pelvic inflammatory disease.

OBJECTIVE: To study the microbiology and long term prognosis of pelvic inflammatory disease (PID). DESIGN: A prospective study of women with laparoscopically confirmed PID. SETTING: Teaching hospital in central London. SUBJECTS: 23 women with PID. OUTCOME MEASURES: Microbiological investigations at the time of diagnosis and at follow up; subsequent fertility and the occurrence of pelvic pain. RESULTS: PID diagnosed by laparoscopy was regarded as moderate to severe in 15 cases. Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum or a combination of these micro-organisms were detected most frequently in the cervix, less often in the endometrium and least in the tubes, C. trachomatis being the micro-organism found most commonly in the tubes. There was serological evidence of acute chlamydial infection in 13 of 20 cases in which paired sera were available and a serological response to M. hominis in 9 of 12 cases in which it was possible to evaluate the results. On the basis of microbiological and serological results, C. trachomatis appeared to be the most important aetiological agent in 10 cases, N. gonorrhoeae in four cases, M. hominis in three cases and U. urealyticum in none; in five cases, two of these micro-organisms appeared to be of equal importance. After 1 to 3 years, 33% of the women were having difficulty conceiving and 56% continued to complain of pelvic pain. CONCLUSION: It is difficult to be certain of the infectious cause of PID in any given case. However, the evidence that N. gonorrhoeae and C. trachomatis are pathogens is very strong. M. hominis may be responsible for a few cases on its own or together with other micro-organisms.

Cervix Uteri↗
PubMed1992

Diagnosis of bacterial vaginosis in a gynaecology clinic.

OBJECTIVE: To estimate the prevalence of bacterial vaginosis in women referred to a gynaecology clinic, and to compare two methods of diagnosing bacterial vaginosis. SETTING: Gynaecology Clinic at Northwick Park Hospital SUBJECTS: 114 women aged 16 to 65 referred consecutively to the gynaecology clinic of one consultant. MAIN OUTCOME MEASURES: Detection of bacterial vaginosis by standard compound criteria and by examination of a Gram stained smear of fluid from the posterior vaginal fornix. RESULTS: Bacterial vaginosis was detected by both the Gram stain and the compound criteria in 13 women. There was no correlation between the symptom of vaginal discharge and the diagnosis of bacterial vaginosis in this population, but the presence of discharge noted by the clinician was associated with bacterial vaginosis. CONCLUSIONS: The prevalence of bacterial vaginosis was 11%. The Gram stain provides a simple and inexpensive method for laboratory confirmation of bacterial vaginosis where facilities for using the compound criteria are not available.

Adolescent↗
PubMed1992

Small numbers of Chlamydia trachomatis elementary bodies on slides detected by the polymerase chain reaction.

A method is described in which smears on slides, which had been examined previously in a direct fluorescence antibody (DFA) test for Chlamydia trachomatis, were tested by the polymerase chain reaction (PCR). Twenty four (73%) of 33 smears which contained fewer than 10 elementary bodies when examined by the DFA test were positive by the PCR. Of the nine negative smears, seven contained only one or two elementary bodies. However, single elementary bodies were detected by the PCR in seven of the 24 positive samples. Fifteen smears were negative by both methods. The ability to detect small numbers of elementary bodies by the PCR and its specificity for negative smears indicates its potential for retrospective analysis of stored, archival smears on slides.

Chlamydia Infections↗
PubMed1992

Penile dermatoses: a clinical and histopathological study.

OBJECTIVE: To assess the spectrum of genital dermatological conditions affecting men and compare the clinical and histopathological diagnoses. DESIGN: Prospective study over a one year period. SETTING: A central London teaching hospital. PATIENTS: Seventy one patients with unresponsive penile dermatoses attending a specific internal referral clinic within the department of genitourinary medicine and 36 patients undergoing penile biopsy following attendance at other departments within the same hospital. METHODS: Full dermatological assessment of patients attending the specific clinic. Standard histopathological methods were used in the diagnosis of biopsy specimens. OUTCOME MEASURED: Clinico-pathological diagnosis of cutaneous penile abnormalities. RESULTS: Description of the range and relative frequency of penile dermatological conditions. The most common histopathological diagnosis was of non specific dermatitis. Twenty seven percent (16 of 61) of patients attending the specific clinic and 33% (12 of 36) of men attending other departments had conditions requiring long term follow up. CONCLUSIONS: The ranges of penile dermatoses presenting to the different departments were broadly similar. Penile biopsy was shown to be a safe and clinically informative procedure. In the genitourinary clinic setting, clinical diagnosis prior to biopsy was found frequently to be inaccurate.

Adolescent↗
PubMed1992

Genetic susceptibility to chlamydial salpingitis and subsequent infertility in mice.

Groups of mice from genetically defined inbred strains were infected genitally with a pathogenic human strain of Chlamydia trachomatis and their subsequent fertility was compared. The CBA, C3H (H-2o) and C3H/He-mg (H-2k) mice were less fertile than control mice, at least up to 6 months after infection. In contrast, fertility was not impaired in BALB/c mice or in congenic BALB/K mice, which had the H-2k haplotype. Reduced fertility was paralleled by the extent of histological oviductal inflammation in mice of each strain. No salpingitis was seen 21 days after infection in the BALB strains, but lesions were apparent in CBA and C3H strains up to about 70 days after inoculation and these sometimes developed into hydrosalpinges. These results indicate that susceptibility to chlamydial salpingitis and subsequent infertility is under genetic control. This control was not simply associated with the major H-2 gene complex, as mouse strains of the same haplotype (H-2k) differed in susceptibility. The fertility of BALB/c (H-2d) and BALB/K (H-2k) strains was no different from that of controls, and congenic C3H mice of differing H-2 haplotypes (H-2k and H-2o) showed reduced fertility. Although all the infected F1 (BALB/K x C3H/He-mg) mice produced litters at the same rate as untreated controls, the litters were considerably smaller. This was due to the occurrence of unilateral pregnancies in the mice inoculated under the ovarian bursae and possibly also to early fetal death in mice inoculated directly in the uterus. These findings emphasize the importance of early diagnosis and treatment of infection of the lower genital tract of women.

Animals↗
PubMed1991

Evidence that patients presenting with dyskaryotic cervical smears should be screened for genital-tract infections other than human papillomavirus infection.

One hundred and fifty-four women with dyskaryotic cervical smears were referred for colposcopy from two distinct population groups, namely those who initially had attended a sexually transmitted disease (STD) clinic, and those who came from general practitioners and family planning and gynaecology clinics (non-STD group). They were investigated to determine the prevalence and pattern of concomitant lower genital-tract infections. The mean age in each group was 25 years. Microbiological studies revealed that 79 (51%) of the women were infected, more than one infection occurring in 16 (10%) of them. Infection was present in 40% of the non-STD group and 66% of the STD group. The pattern of infection was remarkably similar in each group. Bacterial vaginosis was the most common disease in each group and accounted for more than one-third of all infections detected. Six patients had genital warts, 15 harboured Chlamydia trachomatis and 4 had gonorrhoea. Two-thirds of those with C. trachomatis and half of those with gonorrhoea were asymptomatic. We conclude that an abnormal cervical smear is frequently a marker of concomitant lower genital tract infection. Comprehensive microbiological investigations in order to effect appropriate treatment are easily achieved on women in the STD group, but the cost may be seen as prohibitive for those in the non-STD group. For these women we suggest a less comprehensive microbiological approach that provides a compromise strategy of management.

Chlamydia Infections↗