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D Taylor-Robinson

Publications and source records attributed to D Taylor-Robinson.

At least 91 records · Page 5Linked to original sources
PubMed1997

Genital mycoplasma infections.

Since 1937, 13 Mycoplasma species, two Acholeplasma species, and one Ureaplasma species have been isolated from humans. Six of these have the urogenital tract as the primary site of colonisation but others, which have the oropharynx and respiratory tract as the primary site, are found occasionally in the urogenital tract because of orogenital contact. Mycoplasma hominis was the first to be isolated and is most strongly associated with bacterial vaginosis (BV), together with a variety of other bacteria. Its involvement in pelvic inflammatory disease (PID) and other conditions may be as part of BV, although when isolated in pure culture from the blood of women who have postpartum or postabortal fever there is no reason to suspect its aetiological role. There is evidence for an aetiological role for Ureaplasma urealyticum organisms (ureaplasmas) in acute non-gonococcal urethritis (NGU) and particularly chronic NGU in men, but they rank third to Chlamydia trachomatis and M. genitalium. Whether the association of ureaplasmas with miscarriage and preterm labour is in the context of BV is not clear. Of no doubt, however, is the ability of ureaplasmas to cause septic arthritis in hypogammaglobulinaemic patients and there is evidence that they may cause some cases of sexually acquired reactive arthritis. The advent of polymerase chain reaction technology has seen an advance in the understanding of the role of M. genitalium; there is strong evidence that it is one of the causes of both acute and chronic NGU independent of C. trachomatis. There is some support for the role of M. genitalium in PID, but this needs to be substantiated. Other mycoplasmas, for example M. fermentans, M. pivum, M. primatum, M. penetrans, M. spermatophilum and even M. pneumoniae have the capacity to cause urogenital tract disease but there is no evidence to indicate that they do so.

Acholeplasma↗
PubMed1997

A placebo-controlled, double-blind prospective study in healthy female volunteers of dextrin sulphate gel: a novel potential intravaginal virucide.

A double-blind, placebo-controlled study was designed to evaluate the safety and tolerability of intravaginal dextrin sulphate (D2S) gel to assess its preliminary suitability as a potential vaginal virucide. Tolerability was assessed by questionnaire and patient interview. Colposcopy with vaginal biopsy was performed to assess the macroscopic and microscopic evidence of inflammation. The potential impact of the gel on normal vaginal flora was examined by quantitative lactobacilli culture with assessment of the ratio of peroxide to nonperoxide-producing organisms. Colposcopy revealed mild erythema in five of 24 subjects receiving active gel and in none of the 12 placebo recipients, but histology in all subjects revealed no evidence of inflammation. No impact on vaginal lactobacilli was found. We conclude that D2S gel is safe and well tolerated intravaginally at the dosing schedule used in this study.

Administration, Intravaginal↗
PubMed1997

Relationship between hydrogen peroxide-producing strains of lactobacilli and vaginosis-associated bacterial species in pregnant women.

This study was conducted to determine the relationship between lactobacilli and bacterial species associated with bacterial vaginosis in pregnancy and the prevalence of H2O2-producing and non-producing strains of lactobacilli in pregnant women whose vaginal flora had already been analysed. Information was available for 174 pregnant women whose vaginal flora had been evaluated previously by examining gram-stained vaginal smears: 50 had grade III flora (bacterial vaginosis). 50 grade II flora, 41 flora graded as abnormal which then reverted to grade I (revertants) and 33 normal flora (controls). Lactobacilli were isolated from 19 of 50 women whose vaginal flora was grossly abnormal culturally and categorised as grade III by Gram staining. In 6 of these 50 women lactobacilli were isolated in large numbers, i.e. 10(5)-10(6) cfu/ml. H2O2-producing strains of lactobacilli were isolated from 11 of 12 women with grade III flora who were randomly selected from this group. Thus, in those 11 women it appears that H2O2-producing lactobacilli had not protected them from developing bacterial vaginosis. Bacterial species associated with vaginosis were isolated in high numbers from a large proportion of women in the revertant and grade II groups in association with high counts of lactobacilli. Thus, in some women it is possible that a change to an abnormal flora could occur before the complete disappearance of lactobacilli. It is concluded that bacterial vaginosis may develop in some women despite the presence of H2O2-producing strains of lactobacilli and that other factors, as yet unidentified, might be conducive to the appearance of abnormal bacterial flora with progression to vaginosis.

Bacteria↗
PubMed1997

Association of antibodies to Chlamydia trachomatis heat-shock protein 60 kD with chronic nongonococcal urethritis.

Ninety male patients with acute nongonococcal urethritis (NGU) who presented for follow-up 10-92 days after initiation of treatment were evaluated. A polymerase chain reaction assay and direct fluorescence antibody test were used to detect Chlamydia trachomatis at presentation and during follow-up. Chlamydial heat-shock protein 60 kD (hsp60) serology with an enzyme-linked immunosorbent assay and C. trachomatis serology with a microimmunofluoresence test were undertaken. In 62 (69%) of the men, evidence of chronic urethritis was noted during follow-up. C. trachomatis was detected in only two patients during follow-up. Chlamydial hsp60 antibody was associated with the development of chronic urethritis between 10 and 92 days after treatment began (P < .04), that is, at 10-29 days (P < .02) and at 30-92 days (P < .008). These results are consistent with the theory that immune response to hsp60 is important in the development of this chronic disease. The results also suggest that chronic NGU is not a consequence of continued production of hsp60 by C. trachomatis.

Adult↗
PubMed1997

Antibiotic susceptibilities of mycoplasmas and treatment of mycoplasmal infections.

Mycoplasmas are the smallest free-living microorganisms, being about 300 nm in diameter. They are bounded by a triple-layered membrane and, unlike conventional bacteria, do not have a rigid cell wall. Hence, they are not susceptible to penicillins and other antibiotics that act on this structure. They are, however, susceptible to a variety of other broad-spectrum antibiotics, most of which only inhibit their multiplication and do not kill them. The tetracyclines have always been in the forefront of antibiotic usage, particularly for genital tract infections, but macrolides are also widely used for respiratory tract infections. Indeed, in comparison with the tetracyclines, erythromycin, the newer macrolides, the ketolides and the newer quinolones have equal or sometimes greater activity. The two latter antibiotic groups also have some cidal activity. The antibiotic susceptibility profiles of several mycoplasmas of human origin are presented, those of Mycoplasma pneumoniae and Mycoplasma genitalium being similar. Apart from the penicillins, mycoplasmas are innately resistant to some other antibiotics, for example the rifampicins. In addition, some may develop resistance, either by gene mutation or by acquisition of a resistance gene, to antibiotics to which they are usually sensitive. Resistance of mycoplasmas to tetracyclines is common and due to acquisition of the tetM gene. The antibiotic susceptibility pattern may be influenced greatly by the source of the mycoplasma; for example, one recovered from a contaminated eukaryotic cell culture that has been subjected to extensive antibiotic treatment may have an antibiotic profile quite different from the same mycoplasmal species that has been recovered directly from a human or animal source. Mycoplasmas may be difficult to eradicate from human or animal hosts or from cell cultures by antibiotic treatment because of resistance to the antibiotic, or because it lacks cidal activity, or because there is invasion of eukaryotic cells by some mycoplasmas. Eradication may be particularly difficult in immunosuppressed or immunodeficient individuals, particularly those who are hypogammaglobulinaemic. The regimes that are most likely to be effective in the treatment of respiratory or genitourinary mycoplasmal infections are presented.

Animals↗
PubMed1997

Mycoplasmal arthritis in patients with primary immunoglobulin deficiency: clinical features and outcome in 18 patients.

A survey of 358 patients with primary antibody deficiency shows that mycoplasmal infection is the commonest cause of severe chronic erosive arthritis. We review our experience with 18 patients with confirmed or probable mycoplasmal arthritis. There was a broad spectrum of severity from a monoarthritis rapidly responding to tetracyclines to severe debilitating polyarthritis, sometimes with antibiotic-resistant organisms which in two cases were eliminated following hyperimmune animal serum therapy. Most patients had very low serum 1gG levels at the onset of arthritis, suggesting that maintaining levels within the normal range with immunoglobulin replacement may prevent infection. The unique susceptibility of these patients to mycoplasmal arthritis shows that antibodies play a crucial role in protection against these organisms.

Adolescent↗
PubMed1997

An association between non-gonococcal urethritis and bacterial vaginosis and the implications for patients and their sexual partners.

OBJECTIVES: The aetiology of non-gonococcal urethritis (NGU) in a considerable proportion of men remains unaccounted for. We wished to investigate the possible aetiological role of bacterial vaginosis (BV), the commonest cause of abnormal discharge in women, in this condition. METHODS: We carried out two studies. In the first, case-control, study, we recruited men with and without NGU and examined their female partners for evidence of BV. The second, cohort design, study which ran concurrently with the first study involved recruiting women with and without BV and examining their male partners for evidence of NGU. The diagnoses of both NGU and BV were made microscopically to include symptomatic and asymptomatic individuals in both disease categories. RESULTS: In the case-control study 51 couples were recruited. Of these 39 men had NGU and 12 (31%) of their female contacts had BV. In contrast, of 12 men without NGU, only one (8%) of the female partners had BV (odds ratio 4.89, 95% CI: 0.51-42.27). When only Chlamydia trachomatis negative patients were considered, the odds ratio for an association between BV and NGU was increased to 6.77, 95% CI: 0.73-62.68). Thirty eight couples were recruited to the cohort design study. Of 17 women with BV, 12 (71%) of their male partners had NGU. In contrast, of 21 women without BV, seven (33%) of their male partners had NGU (p = 0.049, odds ratio 4.8). When only C trachomatis negative patients were considered, the significance of the association was increased (p = 0.037; odds ratio 5.42). CONCLUSIONS: An association exists between NGU and BV, and vice versa. If BV arises de novo the findings could help to explain the development of urethritis in stable sexual relationships.

Adult↗
PubMed1997

Silent upper genital tract chlamydial infection and disease in women.

To find what proportion of women with endocervical Chlamydia trachomatis infection had asymptomatic infection of the upper genital tract, 10 women with neither gonorrhoea nor signs, symptoms or a past history of pelvic inflammatory disease were laparoscoped. Swabs from the fimbriae and pouch of Douglas were tested for C. trachomatis by tissue culture, enzyme immunoassay, direct fluorescent antibody and polymerase chain reaction techniques. Four of the women had an upper genital tract chlamydial infection. Neither laparoscopic appearances, menstrual phase, interval since last intercourse, partner change nor other coincidental genital infection was associated with the upper genital tract spread. These findings suggest that careful investigation, immediate treatment and contact tracing are mandatory when asymptomatic endocervical chlamydial infection is discovered.

Adolescent↗
PubMed1997

A longitudinal study of the vaginal flora over a menstrual cycle.

Healthy female volunteers participated in an anonymous study to monitor vaginal flora by taking daily vaginal samples and making a smear for later Gram-staining, as well as recording information on genital symptoms, sexual activity, contraceptive and bathing practices. A modification of Spiegel's criteria was used to categorize the Gram-stained smears, an intermediate category between normal flora and bacterial vaginosis (BV) being recognized. Of the 22 volunteers who completed the study, one was excluded because of pregnancy. Of the remaining 21 women, 10 (48%) had a normal flora throughout the study, 4 (19%) had an abnormal flora throughout and 7 (33%) had a basically normal flora which underwent a change to either an intermediate flora in 5 women or fully developed BV in 2 of them. In 5 (71%) of these women the change occurred within the first 9 days of the cycle. Transient changes in the vaginal microbial flora occurred predominantly in the first part of the menstrual cycle which suggests that in some women hormonal changes could have a role in the pathogenesis of bacterial vaginosis.

Candida↗
PubMed1997

Evaluation and comparison of tests to diagnose Chlamydia trachomatis genital infections.

Infection with Chlamydia trachomatis results in intracytoplasmic inclusions and the generation of infectious elementary bodies (EBs). These can be detected by various procedures. Staining of epithelial cells with vital dyes was first used to detect inclusions, but is insensitive. Thus, Papanicolaou-stained cervical smears cannot be recommended. The advent of the ability to grow chlamydiae in cultured cells over 30 years ago had a major impact on chlamydial research and on detection. However, this procedure is probably <70% sensitive for cervical infection and less for urethral infection in men and is now practised infrequently following the advent of other, mostly less laborious and often equally, or more sensitive detection systems. Thus, staining a smear with a specific fluorescent monoclonal antibody to detect EBs is simple and the direct fluorescent antibody tests became a commercial proposition in the early to mid-1980s. Nevertheless, although highly sensitive and specific in competent hands, technical expertise is crucial and even the most experienced may be unable to read a large number of stained smears on slides quickly. In view of this, it is understandable that enzyme-linked immunosorbent assays (ELISAs) gained popularity from the mid-1980s onwards, for they are not very labour intensive and their reading is neither subjective nor tedious. Unfortunately, these aspects outweighed the fact that the ELISAs lack sensitivity, some being very insensitive. The situation has been rescued, however, by the advent in the early 1990s of methods that amplify chlamydial DNA, making it easily detectable by relatively simple procedures. The polymerase chain reaction is such a method and has high specificity and sensitivity, although commercial development has so far not met the high standard expected of it in terms of sensitivity. The ligase chain reaction does not invoke such criticism, and high values for both sensitivity and specificity may be expected, even on urine samples. This augers well for diagnosing an infected individual patient and for effective screening programmes. Antibody tests have no place in a screening programme and are of debatable value in diagnosis.

Chlamydia Infections↗
PubMed1996

Failure to detect Mycoplasma fermentans, Mycoplasma penetrans, or Mycoplasma pirum in the urethra of patients with acute nongonococcal urethritis.

Urethral swab specimens collected from 108 male Japanese patients with acute nongonococcal urethritis (NGU) and from 50 Japanese men without NGU were examined for the presence of Mycoplasma fermentans, Mycoplasma penetrans, and Mycoplasma pirum by means of polymerase chain reaction-based assays. These mycoplasmas were not detected in any of the specimens, which suggests that they are unlikely to have a pathogenic role in acute NGU.

Acute Disease↗
PubMed1996

Common variable immunodeficiency presenting as a Mycoplasma hominis septic arthritis.

A case is reported of common variable immunodeficiency (CVID) presenting as an acute septic arthritis due to Mycoplasma hominis. The diagnosis was not considered until the hypogammaglobulinaemia was discovered and the synovial fluid cultured specifically for mycoplasmas. The importance of diagnosing immunodeficiency states and searching for mycoplasmas in 'bacteriologically culture negative' cases is emphasized.

Adult↗