Craig Tipple

High prevalence of macrolide resistant Treponema pallidum strains in a London centre

Objectives Macrolide resistant Treponema pallidum strains, caused by mutations in the 23S ribosomal RNA (23S rRNA) gene, are widespread and increasingly prevalent. The authors aimed to establish the strain types of T pallidum isolated from patients in a London sexual health centre and to determine the frequency of macrolide resistance. Methods T pallidum DNA from blood and ulcer samples were subjected to strain typing and mutation analysis using previously described methods. Results 18 samples were tested and a 23S rRNA point mutation conferring macrolide resistance was found in 66.6%. All resistant strains were collected from men who have sex with men and both the A2058G and the A2059G mutations were found. Two strain types were identified (14d/g and 14d/f); the predominant strain type was 14d/g and an association was noted between tp0548 type g and macrolide resistance. Conclusions High levels of T pallidum macrolide resistance are present in London, UK, and this has clear implications for national treatment guidelines.

Getting the measure of syphilis: qPCR to better understand early infection

Objectives Until recently, PCR had been used to detect but not quantify Treponema pallidum. To understand infection kinetics of this uncultivable organism, a real-time PCR assay was developed to quantify 47 kDa membrane lipoprotein gene DNA (tpp47). Methods Assay specificity was determined against DNA from humans, skin organisms and sexually transmitted pathogens. tpp47 DNA (Nichols strain) was used to construct a standard curve for T pallidum quantification. Blood and ulcer samples were obtained from 99 patients being investigated or screened for syphilis and tpp47 was quantified. Results The assay was specific, not cross-reactive with other organisms tested and sensitive, with a detection limit of a single copy of tpp47 DNA. For ulcer samples, the assay was 100% sensitive and 97.14% specific. Sensitivity fell to 34.1% for blood samples but specificity remained high (100%). tpp47 DNA was more commonly detected, and at a higher copy number, in blood of patients with secondary infection (sensitivity 57.89%) compared with primary infection. Quantity of tpp47 DNA was higher in primary infection ulcers, especially in HIV-1-positive patients, than in ulcers persisting into secondary disease. Conclusions Quantifying T pallidum provides insight into syphilis infection kinetics: Ulcers of primary disease in HIV-1-positive patients are perhaps more infectious and the presence and load of T pallidum bacteraemia is variable, with a peak in the secondary stage. Quantitative PCR has the potential to map T pallidum infection and to highlight the impact of HIV on syphilis.

Syphilis testing, typing, and treatment follow-up: a new era for an old disease.

Purpose of review The past 15 years have seen a dramatic increase in syphilis diagnoses in several regions including China, North America, Western Europe and Australia. Worldwide, the disease remains prevalent, contributing to substantial adult morbidity and neonatal mortality. Testing and treatment strategies are largely informed by data from the early antibiotic era, but increasing use of molecular diagnostics and new screening strategies could improve the management of syphilis substantially. Recent findings The review explores new testing strategies for syphilis, including the importance of screening test selection and advances in point-of-care diagnostics. It then examines molecular studies of Treponema pallidum, covering typing; macrolide resistance; association between genotype and phenotype and the use of PCR in testing and monitoring strategies. Summary Clinicians should be aware of testing strategies employed by their laboratories to ensure optimal sensitivity and specificity. Locally available T. pallidum PCR assays may improve the diagnosis of early disease and inform antibiotic choice. Robust serologic follow-up is still required, but predictors of potential treatment failure, including PCR-measured bacterial load, have been identified. Re-treatment should be considered for patients in the serofast state. The publication of T. pallidum genomes would allow further and more detailed study of strains and disease pathogenesis.

Syphilis: presentations in general medicine.

Syphilis is caused by the spirochete bacteriumTreponema pallidumand can be transmitted both sexually and from mother to child.T pallidumcan infect any organ and produces a clinical disease with a relapsing and remitting course. It is not hard to see, therefore, why it is often described as the great mimic. In this review, we provide an update of modern syphilis epidemiology, clinical presentations, and testing and treatment strategies.

Corneal perforation requiring corneal grafting: a rare complication of gonococcal eye infection

The authors present a case of severe gonococcal conjunctivitis associated with corneal perforation of the right eye in a 25-year-old homosexual man. Inpatient management and corneal grafting were required. The authors demonstrate that Neisseria gonorrhoea should be considered in the presence of purulent conjunctival discharge with a white patch on the cornea or reduced vision. Regardless of whether a patient has genital symptoms, they should be referred urgently to an ophthalmologist to ensure adequate treatment of this rare but sight-threatening complication.

Rapid Treponema pallidum Clearance from Blood and Ulcer Samples following Single Dose Benzathine Penicillin Treatment of Early Syphilis

Currently, the efficacy of syphilis treatment is measured with anti-lipid antibody tests. These can take months to indicate cure and, as a result, syphilis treatment trials require long periods of follow-up. The causative organism, Treponema pallidum (T. pallidum), is detectable in the infectious lesions of early syphilis using DNA amplification. Bacteraemia can likewise be identified, typically in more active disease. We hypothesise that bacterial clearance from blood and ulcers will predict early the standard serology-measured treatment response and have developed a qPCR assay that could monitor this clearance directly in patients with infectious syphilis. Patients with early syphilis were given an intramuscular dose of benzathine penicillin. To investigate the appropriate sampling timeframe samples of blood and ulcer exudate were collected intensively for T. pallidum DNA (tpp047 gene) and RNA (16S rRNA) quantification. Sampling ended when two consecutive PCRs were negative. Four males were recruited. The mean peak level of T. pallidum DNA was 1626 copies/ml whole blood and the mean clearance half-life was 5.7 hours (std. dev. 0.53). The mean peak of 16S rRNA was 8879 copies/ml whole blood with a clearance half-life of 3.9 hours (std. dev. 0.84). From an ulcer, pre-treatment, 67,400 T. pallidum DNA copies and 7.08x107 16S rRNA copies were detected per absorbance strip and the clearance half-lives were 3.2 and 4.1 hours, respectively. Overall, T. pallidum nucleic acids were not detected in any sample collected more than 56 hours (range 20–56) after treatment. All patients achieved serologic cure. In patients with active early syphilis, measuring T. pallidum levels in blood and ulcer exudate may be a useful measure of treatment success in therapeutic trials. These laboratory findings need confirmation on a larger scale and in patients receiving different therapies.

O05.2 Measuring Syphilis: Quantitative PCR Can Be Used to Monitor Treatment Response

Background The humoral response to Treponema pallidum ( T. pallidum), which causes syphilis, is divided into ‘non-specific’ anti-lipid and specific anti-treponemal protein antibodies. A four-fold reduction in anti-lipid antibodies is used to diagnose cure, which can take six or more months. Quantitative PCR (qPCR) can measure T. pallidum DNA copies in blood and ulcer samples. Bacteraemia is more common and of higher load in early disease. We present a pilot study monitoring the early treatment response in patients with infectious syphilis by qPCR. Methods Patients with symptomatic primary or secondary disease were admitted to hospital and following baseline sampling were treated with 2.4 M units of benzathine penicillin. Whole blood was collected into EDTA and Tempus RNA preservation tubes and the ulcer sampled using a philtre paper strip every four hours for T. pallidum DNA ( tpp047 gene) and RNA ( 16S rRNA) quantification. Sampling ended when two consecutive PCRs were negative. Standard serological follow-up was performed. Results Three men were recruited (two secondary, one primary). All were homosexual and two were HIV-1 infected. Blood DNA quantification and clearance: A mean peak-level of 1611(range 1212) tpp047 copies/ml was detected and mean half-life for clearance (t½ clearance) was 7.89 hours (range 5.34). Blood RNA: Mean peak-level 8829(range 20366) 16SrRNA copies/ml blood; (t½ clearance) 5.24 hours (range 0.78). Ulcer DNA 1.14 × 105 copies/strip and RNA 4.35 × 107 copies/strip with a t½ (clearance) of 1.67 and 3.76 hours, respectively. T. pallidum nucleic acids were undetectable in all samples after 56 hours. All patients had serology consistent with disease stage at baseline and cure at one month. Conclusions T. pallidumqPCR presents a novel and quick way of monitoring early syphilis treatment efficacy. Both DNA and RNA may be suitable targets to measure bacterial clearance from blood and ulcer exudates. Ulcers may be non-infectious as soon as 56 hours post-treatment.

Syphilitic aorta: exploring the bigger picture.

Sirs: We read with interest this case report. It raises a number of important issues concerning the diagnosis and management of syphilis. When exploring a diagnosis of syphilis, serology results are notoriously difficult to interpret in isolation, so a clear history of possible previous treponemal infection is paramount. Yaws, pinta and syphilis should all be considered. This information will aid both diagnosis and contact tracing, which should include children of infected mothers were appropriate. Social and sexual history will also highlight the risk of HIV co-infection. Estimated adult HIV prevalence in South Africa was 16.9% in 2008, with women disproportionately affected. HIV can affect the natural history and treatment of syphilis; moreover, syphilis is an independent risk factor for both HIV acquisition (2to 4-fold) and transmission (2to 9-fold), so HIV-testing in this case would have been important. You report that, following treatment, the syphilis serology was negative. We are unclear what this means. Treponemal-specific tests, such as the enzyme immunoassay (EIA) test used in this case, are likely to remain positive for life, even with effective treatment, and non-treponemal tests, such as the rapid plasma reagin, used to monitor the effectiveness of treatment, was negative at baseline and would therefore likely remain so. As you mention, the Jarisch–Herxheimer (JH) reaction is a rare but potentially fatal complication of cardiovascular syphilis treatment as coronary ostial occlusion or rupture of an aortic aneurysm can result from transient inflammation. The British Association for Sexual Health and HIV recommends examination and investigation for both cardiovascular and indeed neurological sequelae of late syphilis prior to treatment and advocate steroids to reduce the risk of a substantial JH reaction. This is particularly indicated for symptomatic cases. However, recently the utility and cost-effectiveness of a plain chest radiograph to exclude cardiovascular syphilis in asymptomatic patients has been called into question. Your pathological findings of periaortic fibrosis and adhesions were interesting. Necropsy specimens studied previously demonstrated adhesions limited to the anterior wall of the left ventricle at the apex and a full-thickness process, described microscopically due to endarteritis of the vasa vasorum. It would be interesting to see a more detailed histological report especially as areas of giant cells were noted, which have been previously described as near-absent from the syphilitic aorta. Finally, polymerase chain reaction of the histological specimen for Treponema pallidum DNA could have been used to add weight to your diagnosis. As a final point, you suggest that cardiovascular syphilis is poised to re-emerge given the large increase in early syphilis diagnoses between 1999 and 2006. We must, however, consider a number of other factors: not all patients with untreated syphilis will develop symptomatic tertiary disease; in the modern antibiotic era many patients receive treponemocidal drugs for other indications that may alter the disease’s natural history and finally that the course of syphilis is altered in HIV-infected patients.

O21.6 A Tale of Two Cities: Treponema Pallidum Macrolide Resistance in Colombo (Sri Lanka) and London (United Kingdom)

Background The bacterium Treponema pallidum ( T. pallidum) causes syphilis. Penicillin is effective treatment, but azithromycin (a macrolide) is a single-dose oral alternative for those with allergy. Unfortunately, macrolide resistance secondary to one of two 23S ribosomal RNA (rRNA) point mutations (A2058G and A2059G) is now wide-spread. Molecular strain-typing suggests that epidemics and macrolide resistance are unlikely the spread of single clones. We present typing and macrolide resistance data from two geographically distinct populations: Colombo, Sri Lanka and London, UK. Methods Cross-sectional studies were conducted at the Colombo District STD clinics and St Mary’s Hospital, London. Ulcer exudate and/or blood were collected from patients with microbiologically confirmed syphilis. Presence of T. pallidum DNA ( tpp047 gene) was confirmed with PCR. Next, using published techniques, the 23SrRNAgene was PCR-amplified for a point-mutation assay and tpp0548, arp and tprE,G& Jamplicons were used for strain-typing. Results Sri Lanka: 24 T. pallidum PCR-positive samples were collected. Patients were men (45.9% MSM) and 91.6% Sinhalese with a mean age of 28 (range 29). None were HIV-1 infected. Two strain types were discovered (14b/f and 13b/f), neither harbouring macrolide resistance. London: 43 men were recruited, 18 in 2006–8 and 25 in 2011–12. Mean age was 37.5 (range 43); 95.2% were MSM and 62.8% were HIV-1 infected. Half (22/43) were white British. A total of 5 full and 14 partial strain types were identified, of which 6 were unique. Macrolide resistance increased from 66.7%(12/18) in 2006–8 to 80%(20/25) in 2011–12. Conclusion Colombo T. pallidumstrains have limited diversity with no macrolide resistance. London strains are more varied and increasingly macrolide-resistant. Ethnic diversity in London exceeds Colombo’s and may explain increased strain diversity. In contrast to Sri Lanka, azithromycin is widely used to treat Chlamydia and non-specific urethritis in the UK thus selection pressure may be driving macrolide resistance.

P62 Managing the cardiovascular complications of late syphilis

Background BASHH recommends full clinical examination and chest radiography (CXR) for patients with late syphilis. Steroid cover and cardiology referral are advised for cardiovascular involvement. Recent literature suggests variation in the clinical management of suspected cardiovascular syphilis. Aim To explore variations in the management of late syphilis in UK GUM clinics and to compare this with current BASHH guidelines. Method Lead clinicians of UK GUM clinics were invited to complete an electronic survey between November and December 2010 to establish management of late syphilis in their centre. Data collected using the online Survey Monkey system were analysed with Microsoft Excel and SPSS V.18. Results In total, 34% (53/156) of clinicians approached responded fully or partially to the survey (93% were consultants). An average of nine cases (n=45, SD 10.8) of late syphilis (KC60 codes A4, A5, A6) per clinic were seen between November 2009 and November 2010. Of these, 76% (n=42, range 0–100%) were estimated to have had a full clinical examination (and the use of CXR is described in abstract P62 table 1). *Other includes: older patients; HIV+ve patients; those with higher RPR; clinician dependent An ECG or ECHO was ordered routinely, or if the patient has symptoms or signs of cardiovascular syphilis, in 90% and 76% respectively. Cardiology referral was routinely made by 58% (18/31) and 35% (9/26) always used steroids, when managing cardiovascular syphilis. Abstract P62 Table 1 Q: Under which circumstances is a CXR requested? Routinely performed If patient symptomatic If patient has clinical signs If routine, symptoms or signs Other* Mean % (no of respondents) n=44 48% (21) 41% (18) 36% (16) 89% (39) 25% (11) * Other includes: older patients; HIV+ve patients; those with higher RPR; clinician dependent. Discussion Management of late syphilis varies both between clinics and compared with BASHH guidelines. Not all patients are examined or offered a CXR, and in cases with suspected cardiovascular involvement, cardiology referral and use of steroids are variable. Conversely, many patients are over-investigated in the GUM clinic.