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Background Strain typing is a tool for determining diversity and epidemiology of infections. Methods T. pallidum DNA was isolated from 158 syphilis patients from the US, China, Ireland, and Madagascar and from 15 T. pallidum isolates. Six typing targets were assessed: 1) number of 60 bp repeats in acidic repeat protein gene; 2) restriction fragment length polymorphism (RFLP) analysis of T. pallidum repeat (tpr) subfamily II genes; 3) RFLP analysis of tprC gene; 4) determination of tprD allele in tprD gene locus; 5) presence of 51 bp insertion between tp0126/tp0127; 6) sequence analysis of 84 bp region of tp0548. The combination of #1 and #2 comprises the CDC T. pallidum subtyping method. Results Adding sequence analysis of tp0548 to the CDC method yielded the most discriminating typing system. Twenty-four strain types were identified and designated as CDC subtype/tp0548 sequence. Type 14d/f was seen in 5 of 6 locations. In Seattle, strain types changed from 1999– 2008 (p<0.001). Twenty-two (50%) of 44 patients infected with type 14d/f had neurosyphilis compared to 9 (23%) of 39 infected with the other types combined (p=0.01). Conclusion We describe an enhanced T. pallidum strain typing system that shows biological and clinical relevance.

The new england journal of medicine n engl j med 351;2 www.nejm.or decades, syphilis infection has been treated with penicillin , and Treponema pallidum has not developed resistance to penicillin. In many countries, the recommended treatment for early syphilis is a single dose of penicillin G benzathine, which maintains bactericidal levels for weeks, killing the slowly metabolizing treponemes. Azithromycin, which has a long tissue half-life and can be administered orally, was found to be effective in the treatment of syphilis in a rabbit model 1 and in small studies in humans. 2-6 Because of its convenience and efficacy, azithromycin is increasingly being used for the treatment of syphilis by clinicians and in disease-control activities in Canada and the United States, although it is not currently recommended by the Centers for Disease Control and Prevention. 7 We discuss one patient with clinical failure of azithromycin therapy for syphilis, among several cases that have been recognized. 8 We identified a mutation in the 23S ribosomal RNA (rRNA) genes in a specimen of T. pallidum obtained from this patient, and we confirmed functional azithromycin resistance in vivo in a strain of T. pallidum that contain this mutation. Testing of T. pallidum samples obtained at four geographically diverse sites revealed a high frequency of this mutation in clinical specimens. samples Swab samples were collected from primary or moist secondary syphilis lesions in patients at

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Aim: To examine the potential of p16INK4A as a biomarker for dysplastic squamous and glandular cells of the cervix in tissue sections and ThinPrep™ smears. Methods: Immunocytochemical analysis of p16INK4A expression was performed on 22 normal cervical tissue samples, five cervical glandular intraepithelial neoplasia (cGIN), 38 cervical intraepithelial neoplasia 1 (CIN1), 33 CIN2, 46 CIN3, and 10 invasive cancer cases (eight squamous and two adenocarcinomas). All samples were formalin fixed and paraffin wax embedded, and immunohistochemical analysis was carried out using a mouse monoclonal anti-p16 INK4A antibody after antigen unmasking. The staining intensity was assessed using a 0 to 3 scoring system. In addition, the expression status of p16 INK4A was examined in 12 normal ThinPrep smears, one smear exhibiting cGIN, and a total of 20 smears exhibiting mild, moderate, and severe dyskaryosis. Human papillomavirus (HPV) detection was carried out using a modified SYBR green assay system. Fluorogenic polymerase chain reaction (PCR) and solution phase PCR were used for specific HPV typing. Results: p16INK4A immunoreactivity was absent in all normal cervical tissues examined. Dysplastic squamous and glandular cells were positive for p16INK4A expression in all cases included in this study, except for one CIN3 case. p16INK4A expression was mainly nuclear in CIN1 cases, and both nuclear and cytoplasmic in CIN2, CIN3, cGIN, and invasive cases. All cases positive for HPV expressed the p16 INK4A protein, although not all cases found positive for p16 INK4A were HPV positive. In general, the p16 INK4A staining intensity was lower in cases negative for HPV or those containing a low risk HPV type. Conclusion: This pattern of overexpression demonstrates the potential use of p16INK4A as a diagnostic marker for cervical squamous and also glandular neoplastic lesions. In addition, the technique can be used to identify individual dyskaryotic cells in ThinPrep smears. Thus, p16 INK4A is a useful marker of cervical dyskaryosis. C ervical cancer is one of the most common forms of cancer in women worldwide. In developing countries, cancer of the uterine cervix is ranked second, with a relative frequency of 15% of all cancers in women, whereas in developed countries cervical cancer is ranked fifth, with a relative frequency of 4.4%.1 The Papanicolaou (Pap) test, as described by G Papanicolaou, is a cytological staining technique, which allows the identification of asymptomatic women who have preneoplastic lesions or early cancer of the uterine cervix. Although the introduction of mass screening programmes in developed countries has been effective in reducing cervical cancer mortality and morbidity rates, the success of the Pap smear test is limited with respect to sensitivity and specificity. False negative rates for cervical premalignant lesions and cervical cancer lie between 15% and 50% and false positive rates of approximately 30% have been reported.2 This failure may reflect the subjectivity of cytological diagnosis. In addition...