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R C Ballard

Publications and source records attributed to R C Ballard.

At least 19 recordsLinked to original sources
PubMed1998

An assessment of care provided by a public sector STD clinic in Cape Town.

A study was undertaken in a Cape Town public sector STD clinic to evaluate the content and quality of care provided since it has been recognized that appropriate improvements in the management of conventional sexually transmitted diseases (STDs), including provision of correct therapy, health education, condom promotion and partner notification, could result in a reduced incidence of HIV infection. Our objectives were to assess patients' needs for health education and to assess the quality of STD management in terms of health education, condom promotion, partner notification, the validity of the clinical diagnoses and the adequacy of the treatments prescribed. The study subjects were sampled systematically, according to their gender. Patients included in the study were given a standardized interview and their clinical records reviewed. Specimens were collected for laboratory investigations. For each STD detected, the treatment was defined as adequate if drugs currently known to be active against that infection were prescribed. One hundred and seventy men and 161 women were included in the study (median age: females 22 years, males 26 years). While almost all patients believed their STD may have been caused by unprotected sexual intercourse, many also believed it may have been caused by other factors, such as bewitchment with traditional medicine. Only 21% of male and 37% of female patients received any education about STD transmission during the clinic visit, and only 25% of male and 36% of female patients received education about condom use. As a result of the low sensitivity of the clinicians' diagnoses, 16% of men and 61% of women left the clinic with at least one infection inadequately treated. The majority of patients were not receiving education for the prevention of STDs including HIV. Many were not receiving adequate treatment for their infections. The introduction of a syndromic management protocol in this setting would substantially reduce the proportion of inadequately-treated patients. However, syndromic protocols, and the means by which they are implemented, need to take into account problems with the clinical detection of genital ulcerative disease and candidiasis in women.

Adult↗
PubMed1998

Perceptions and patterns of reproductive tract infections in a young rural population in North-West Namibia.

Syndromic management of sexually transmitted diseases (STDs) is strongly promoted in Namibia. However, no data are available on rates of asymptomatic reproductive tract infections (RTIs) which would remain undetected and thus untreated in the general population. This study was aimed at assessing the prevalence of RTIs in a young rural population and to gain an insight into their health-care seeking behaviour for RTIs. A total of 97 patients (44 male, 53 female) <30 years of age attending the outpatient clinic of a rural hospital in Northern Namibia for problems unrelated to RTIs were interviewed and examined. Specimens were taken for investigation of RTIs according to a non-invasive diagnostic schedule. Laboratory examinations revealed 58 infections of the reproductive tract in 42 of the 97 patients (43%). In addition, HIV infection was detected in 13 cases (13%). RTI rates were highest in female teenagers (68%), but no infections were detected in their male counterparts. Of those 42 patients with a laboratory-diagnosed infection, 7 had both symptoms and signs (symptomatic), 16 had neither symptoms nor signs (asymptomatic), and 19 had signs on examination but no symptoms (inapparent). Awareness and perception of symptoms and signs of RTIs were low in the studied population. Provision of adequate treatment for RTIs alone is unlikely to have a major impact on the overall burden of disease since the largest burden of disease was found among those patients (predominantly females) with inapparent infections. Health education on RTIs including STDs and the symptoms they cause together with the importance of early attendance at health facilities and improved access to treatment need to be addressed urgently.

Adolescent↗
PubMed1998

Comparison of clinically directed, disease specific, and syndromic protocols for the management of genital ulcer disease in Lesotho.

OBJECTIVE: To evaluate two protocols for the syndromic management of genital ulcer disease (GUD) in Lesotho, southern Africa and to compare the performance of these protocols with that of a conventional disease specific approach. METHODS: A cross sectional study was conducted among consecutive patients with GUD attending an STD clinic in Maseru, Lesotho. The clinical diagnoses were made by using predefined criteria at the initial visit before the performance of laboratory tests. Attempts were made to detect the specific aetiology of the genital ulcers using PCR assays and syphilis serology. The results of PCR assays and syphilis serology were used as the gold standard against which the performance of the management approaches were applied. RESULTS: Of 100 patients initially recruited into the study, Haemophilus ducreyi infection was detected in 56%, herpes simplex virus in 26%, Treponema pallidum in 23%, and lymphogranuloma venereum in 7%. No pathogens were detected in 6% of patients. 17% of patients had mixed infections. Sensitivity, specificity, positive and negative predictive values of the three management protocols for GUD were compared after applying each to the study population. Theoretically, the lowest correct treatment rate would have been obtained by using the disease specific protocol (62%) compared with more than 90% in both syndromic management protocols. Considerable overtreatment for primary syphilis would occur following application of both syndromic protocols. This would be the result of the overdiagnosis of chancroid, in particular the misdiagnosis of genital herpes as chancroid, which would receive treatment for syphilis unnecessarily. The HIV seroprevalence among these patients was 36%. A significantly higher rate of HIV seropositivity was detected among the patients with herpes simplex virus infection when compared with those patients having other causes of genital ulcer disease (58% v 27%; odds ratio 3.73; 95% CI 1.26-11.26; p = 0.01). CONCLUSIONS: Poor sensitivity, specificity, and predictive values were recorded when the disease specific protocol was applied to the study population. In contrast, the syndromic management protocols provided adequate treatment for more than 90% of patients with GUD. Protocol C, which identified a minority of cases of genital herpes, was found to have an advantage when compared with protocol B (all patients with genital ulcer disease treated for both syphilis and chancroid) in that 29% of genital herpes cases would receive appropriate counselling.

Chancroid↗
PubMed1998

Screening for sexually transmitted diseases in rural South African women.

OBJECTIVE: This paper reports on a study undertaken in a rural area of South Africa, to develop a non-laboratory tool to screen for sexually transmitted diseases (STDs) among family planning clients. METHODS: A cross sectional study was performed of 249 consecutive women attending a family planning service between November and December 1994. A questionnaire was administered, and a clinical examination and laboratory tests conducted. Sociodemographic, clinical, and other non-laboratory variables that were significantly associated with laboratory evidence of infection were combined to produce non-hierarchical scoring systems for three "syndromes": gonococcal and/or chlamydial cervical infection, trichomoniasis, and cervical infection and/or trichomoniasis combined. The sensitivity, specificity, and predictive values of the scoring systems as a screening tool were assessed against the gold standard of laboratory tests. RESULTS: The prevalence of reproductive tract infections among the study participants was as follows: Chlamydia trachomatis 12%, Neisseria gonorrhoeae 3%, Trichomonas vaginalis 18%, and bacterial vaginosis 29%. Although vaginal discharge and other symptoms were frequently reported, symptoms bore no relation to the presence of infection. The following independent associations with gonococcal/chlamydial cervical infection were found: age less than 25 years and cervical mucopus and/or friability. Abnormal discharge on examination, visible inflammatory changes of the cervix (increased redness), no recent travel, and unemployment were associated with trichomoniasis. The combination of trichomonas and/or cervical infection ("STD syndrome") was associated with cervical mucopus/friability, unemployment, lack of financial support, and increased redness of the cervix. Of the three scoring systems developed on the basis of these associations, that of the "STD syndrome" achieved the best performance characteristics as a screening tool, with a sensitivity of 62%, specificity of 74%, and positive predictive value of 48%. CONCLUSION: STDs are common in a population of rural, sexually active women attending a family planning service. In resource poor settings, non-laboratory screening tools could play some role in identifying and treating infections in these women, especially since the majority would not otherwise have been reached. However, such screening tools cannot be viewed as the only way to identify STDs and should be considered as part of an overall strategy of STD control that includes, for example, good management of symptomatic individuals and their partners.

Adolescent↗
PubMed1997

Comparison of clinical diagnosis and standard laboratory and molecular methods for the diagnosis of genital ulcer disease in Lesotho: association with human immunodeficiency virus infection.

A multiplex polymerase chain reaction (M-PCR) assay for Haemophilus ducreyi, Treponema pallidum, and herpes simplex virus (HSV) was compared with clinical and standard laboratory methods for the diagnosis of genital ulcer disease (GUD) in 105 patients; 36% were human immunodeficiency virus (HIV)-seropositive. Chancroid (80%), syphilis (8%), and genital herpes (8%) were the most frequent diagnoses. H. ducreyi and HSV were isolated from ulcers of 43% and 18% of patients, respectively; in 35%, all cultures were negative and the laboratory diagnosis indeterminate. M-PCR detected H. ducreyi, T. pallidum, and HSV in 56%, 23%, and 26% of patients, respectively; (no definitive diagnosis, 6%). The proportion of patients with more than one agent was 4% by culture and 17% by M-PCR (P = .002). Resolved sensitivities of M-PCR for H. ducreyi and HSV cultures were 95% and 93%, respectively. The sensitivities of H. ducreyi and HSV cultures were 75% and 60%, respectively. HSV, detected in 47% of specimens from HIV-infected versus 16% from HIV-uninfected patients (P < .001), may be emerging as a more frequent cause of GUD.

Adolescent↗
PubMed1997

Cefaclor, an alternative to third generation cephalosporins for the treatment of gonococcal urethritis in the developing world?

OBJECTIVE: To reassess the in vivo and in vitro efficacy of cefaclor for the treatment of uncomplicated gonococcal infection. DESIGN: Open clinical trail conducted in South Africa among consecutive male patients with symptoms and signs of uncomplicated urethritis and laboratory evidence of gonorrhoea. METHODS: Patients were treated with 3 g of cefaclor plus 1 g probenecid as a single dose. Urethral specimens were cultured for Neisseria gonorrhoeae at the initial visit and at follow up. Patients were considered cured if follow up cultures were negative. Treatment was considered to have failed in the patients infected with identical gonococcal strains at the initial and at the control visit. Those with evidence of infection at the follow up visit were administered 400 mg of ofloxacin and doxycycline 100 mg twice daily for 7 days. Minimal inhibitory concentrations (MICs) of cefaclor were determined by an agar dilution technique on the gonococcal isolates from the study subjects. The results were compared with those of isolates from three other African countries. RESULTS: Of 155 patients evaluated, 151 were cured (97%). Thirty per cent of the patients complained of adverse effects, mainly gastrointestinal. Even though MICs for the isolates from the three other African countries were significantly higher than those for the isolates from the study, none was considered resistant to cefaclor in vitro. MICs were markedly influenced by the type of test medium used. CONCLUSION: The trial demonstrated the efficacy of a single oral dose of cefaclor with probenecid for the treatment of uncomplicated gonococcal urethritis in South Africa. Its potential as an alternative therapy to third generation cephalosporins deserves to be further investigated.

Administration, Oral↗
PubMed1997

An evaluation of the capillus HIV-1/HIV-2 latex agglutination test using serum and whole blood.

The capillus HIV-1/HIV-2 latex agglutination (LA) test was evaluated for its potential as an initial screening test in primary health care. For the serum study, panels totalling 289 HIV-positive sera and 323 known HIV-negative sera plus 50 individual seroconversion samples were tested by capillus. Paired blood specimens were also collected in heparinized and plain tubes from 501 consecutive patients with newly diagnosed sexually transmitted diseases (STDs) attending an STD clinic at a Transvaal hospital. Overall, an initial sensitivity of 99.3% and an initial specificity of 99.7% were obtained by visual reading of the capillus HIV-1/ HIV-2 LA tests on serum samples. Capillus also detected 40 (80%) of the 50 seroconversion samples. Of the 501 paired plain and heparinized blood specimens, serum testing by enzyme immunoassay (EIA) and indirect immunofluorescence/ Western blot (IFA/WB) showed 147 (29%) to be HIV Ab positive. Capillus testing of the paired specimens correctly identified all 147 known positive patients and 345 of the 346 negative patients, thus showing an initial sensitivity of 100% and an initial specificity of 99.7% for the testing of heparinized whole blood by a relatively unskilled health worker. It was concluded that the capillus HIV-1/HIV-2 LA test would be suitable for use as a primary screening test in small outlying laboratories or primary health care clinics.

Blotting, Western↗
PubMed1997

Immunohistochemical investigations of genital ulcers caused by Haemophilus ducreyi.

To gain information on the specific composition of the inflammatory infiltrate of genital ulcers caused by Haemophilus ducreyi, biopsies of 6 genital ulcers which were diagnosed as chancroid on clinical and microbiological grounds were subjected to immunohistochemical investigations after conventional haematoxylineosin staining. A variety of antibodies reactive against B- and T-cells, plasma cells and granulocytes were used with each tissue sections. The lymphocytic infiltrate of chancroid ulcers consisted of both B- and T-lymphocytes and showed a cluster-like formation. B-lymphocytes were preferentially localized perivascularly in the middle layer, T-lymphocytes mainly in the deep layer of the inflamed oedematous tissue. Results stress the importance of both B- and T-cell mediated immune responses in Haemophilus ducreyi infection.

Antibodies, Bacterial↗
PubMed1996

Sexually transmitted diseases in South Africa.

AIM: To review the epidemiology of and data collection for sexually transmitted diseases (STDs) in South Africa. METHODS: Literature published since 1980 on STDs in South Africa were complied and evaluated. Historical reports and salient unpublished literature were also used in the literature review. Studies were critically reviewed in the light of sample populations and study methods, and a baseline picture of the patterns of STD burden was developed. RESULTS: The STD burden in apparently asymptomatic study populations is significant. Ulcerative infections, primarily caused by syphilis and chancroid, are present in 5-15% of asymptomatic clinic attenders; prevalence rates of gonorrhoea average 8%, with up to 13% of gonococcal isolates resistant to penicillin antibiotics. In addition, on average, chlamydia and vaginal infections are detected in 16% and 20-49%, respectively, of antenatal and family planning clinic attenders. HIV seroprevalence rates have reached 7.6% in antenatal clinic attenders. Most South African STD data are derived from ad hoc surveys which have traditionally focused only on several major infections and particular urban centres. Almost all STD studies have been facility-based, with many studies based at STD clinics, thus reporting only relative frequencies and not population-based prevalences of STDs. With the possible exception of HIV, systematic surveillance data for STDs are conspicuously lacking. CONCLUSION: The disease burden of classic sexually transmitted infections has historically been heavy, and continues to be a serious public health problem in South Africa. Morbidity from both ulcerative and non-ulcerative infections, particularly in women, is significant. The body of STD data, although mostly sound, remains incomplete, and with the rapid emergence of HIV in South Africa, surveillance of STDs and focused STD policies will be critical.

Chancroid↗
PubMed1996

Treatment of chancroid with azithromycin.

A randomized, comparative study undertaken in Nairobi, Kenya and a non-comparative evaluation undertaken in Carletonville, South Africa have both shown that a single oral dose of azithromycin 1 g is effective in the treatment of the genital ulcer disease (GUD), chancroid, with cure rates of 89% and 92% recorded respectively. While treatment failure was associated with human immunodeficiency virus seropositivity and lack of circumcision in Kenya, no such association could be found in the South African study. In both series, azithromycin treatment resulted in cure of both Haemophilus ducreyi culture-positive and culture-negative cases of GUD, including two cases subsequently diagnosed as lymphogranuloma venereum. A combination of single-dose azithromycin with single-dose benzathine penicillin may provide effective 'single-visit' syndromic treatment for GUD in many developing countries.

Anti-Bacterial Agents↗
PubMed1996

Chancroid.

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Anti-Bacterial Agents↗
PubMed1995

Specificity of the immune response to Haemophilus ducreyi.

The specificity of the antibody response to Haemophilus ducreyi in sera from patients attending a sexually transmitted disease clinic in South Africa has been studied using immunoblotting. Patients with chancroid were shown to have higher levels of IgG (mean 0.74, SD 0.34) to H. ducreyi than those with no history of chancroid (mean 0.34, SD 0.19). The pattern of the antibody specificity was highly variable between patients with culture proven chancroid but there was no observed strain specificity. In comparison, the patterns obtained using sera from patients without known exposure to H. ducreyi showed less variation between patients and were of less intensity at the dilution used. Sera from patients with chancroid recognised epitopes on proteins that varied in molecular weight between strains, particularly of 60-66kDa (10 of 36 patients) and 25-27kDa (8 of 36 patients). In addition epitopes were recognised on the GroEL and/or DnaK heat shock proteins in 13 of 36 sera tested. There was no apparent change in the epitopes recognised on proteins between the homologous and heterologous strains. Patterns of antibody specificity in sequential sera only varied in one of six patients tested.

Antibodies, Bacterial↗
PubMed1995

Simplified PCR for detection of Haemophilus ducreyi and diagnosis of chancroid.

A simplified PCR was developed for detection of Haemophilus ducreyi in samples from chancroid patients. The strategy included a straightforward chloroform extraction sample preparation method, a one-tube nested PCR to minimize contamination risks, and a colorimetric method for detection of products. Primers were designed from published nucleotide sequences of the 16S rRNA gene of H. ducreyi, with longer outer primers for annealing at a higher temperature and shorter inner primers labelled with biotin and digoxigenin for binding with avidin and colorimetric detection. The PCR technique detected all 35 strains of H. ducreyi tested, from four different geographical regions, and was negative for other, related strains of bacteria and for the common contaminating bacteria tested. Of 25 samples from H. ducreyi culture-positive chancroid patients, 24 were PCR positive and 1 produced a weak reaction. Of 83 samples from clinical cases of chancroid in the Republic of South Africa, 69 were PCR positive. The sensitivity of PCR compared with that of clinical diagnosis was 83%. All 50 negative control samples were negative. Encouraging results were also obtained with a consecutive series of 25 genital ulcer patients in Tanzania, of whom 9 were PCR positive. The adaptations of this simplified PCR strategy, at the sensitivity and specificity levels obtained, mean it will be useful for detection of H. ducreyi in areas where the organism is endemic, particularly where testing by culture is difficult or impossible.

Base Sequence↗
PubMed1995

Characterisation of penA and tetM resistance genes of Neisseria gonorrhoeae isolated in southern Africa--epidemiological monitoring and resistance development.

OBJECTIVE: To investigate penA and tetM resistance gene variation of Neisseria gonorrhoeae in order to define gene types for epidemiological monitoring and resistance development. DESIGN: Isolates of N. gonorrhoeae which were susceptible and resistant to penicillin and/or tetracycline were selected. Strains comprised South African isolates (22 from Bloemfontein, 13 from Transvaal, 20 from the Cape) and 15 Botswana and 4 Namibia isolates. The penA genes (2 kb) of all strains and tetM genes (765 bp) of 11 high-level tetracycline-resistant strains were amplified and restricted with HpaII. RESULTS AND CONCLUSIONS: Twelve different HpaII fingerprint patterns were obtained from the 74 isolates analysed for penicillin-binding protein (PBP) 2 gene (penA) alterations. Focusing on the transpeptidase domain, 25 isolates (3 whole gene patterns, minimal inhibitory concentrations (MICs) < or = 0.03-0.125 micrograms/ml) had restriction sites equivalent to those previously described for a susceptible strain. Of the remaining 9 PBP 2 gene groups, 25 strains fell into a designated group E. Penicillin/ penicillin + clavulanic acid MICs determined on these group E isolates gave a range of 0.125-2.0 micrograms/ml, although MICs against 4 strains were < or = 0.03 micrograms/ml. MICs of penicillin/penicillin + clavulanic acid for the 24 isolates that contained altered PBP 2 transpeptidase gene regions not designated group E were only < or = 0.03-0.125 micrograms/ml. The lack of a HpaII restriction site at nucleotide 1934 in the PBP 2 gene of group E strains was indicative of a small terminal region of N. cinerea DNA. This gene block, which was found in all the southern African areas studied, appears to predispose isolates to increased penicillin resistance. The 25.2 MDa conjugative plasmid carrying the tetM resistance determinant was readily demonstrated in 11 Botswana/Namibia isolates exhibiting high-level resistance to tetracycline (MICs > or = 16 micrograms/ml). The tetM gene was shown to be of the American type.

Drug Resistance, Microbial↗
PubMed1992

A simple medium for the primary isolation of Haemophilus ducreyi.

Two simple, inexpensive media containing gonococcal agar-base, supplemented with 5% Fildes' extract and either chocolated or unchocolated horse blood (GC-FHBC or GC-FHB) were compared with the standard gonococcal agar-based (GC-HgS) and Mueller-Hinton agar-based media (MH-HB) normally used for primary isolation of Haemophilus ducreyi from presumptive chancroid lesions. Overall, Haemophilus ducreyi was recovered from 162 of 178 (91%) samples from primary chancroid lesions. As a single isolation medium GC-HgS proved the most sensitive with an isolation rate of 80% followed by GC-FHB (75%), MH-HB and GC-FHC (both 71%). Use of a combination of GC-HgS and MH-HB resulted in isolation of Haemophilus ducreyi in 160 of 178 cases (90%). Since GC-FHB is approximately one-quarter the cost of the combination and half the cost of GC-HgS or MH-HB alone, this medium could prove suitable for diagnostic purposes in developing countries where chancroid is endemic.

Agar↗
PubMed1992

Lack of immunoglobulin A1 protease production by Haemophilus ducreyi.

A collection of 20 strains of Haemophilus ducreyi including freshly isolated, low-passage and multi-passage reference strains was examined for immunoglobulin A1 protease production by SDS-PAGE and immunoblotting. None of the strains demonstrated IgA1 protease activity despite the fact that different culture media were used. By direct immunofluorescence testing, binding of IgA to Haemophilus ducreyi organisms could be demonstrated.

Blotting, Western↗