Azithromycin-resistant Neisseria gonorrhoeae isolates in Guangzhou, China (2009-2013): coevolution with decreased susceptibilities to ceftriaxone and genetic characteristics.

BACKGROUND: The recent emergence of azithromycin-resistant (AZM-R) N. gonorrhoeae isolates that have coevolved decreased susceptibility to extended-spectrum cephalosporins has caused great concern. Here we investigated the prevalence of decreased susceptibility to ceftriaxone (CRO(D)) in AZM-R isolates and genetically characterized AZM-R isolates in Guangzhou, China from 2009 to 2013. METHODS: The minimum inhibitory concentration (MIC) of AZM and ceftriaxone was determined using an agar-dilution method. All AZM-R isolates were screened for mutations in 23S rRNA, mtrR and penA genes and genotyped using N. gonorrhoeae multi-antigen sequence typing (NG-MAST). RESULTS: Of the 485 identified N. gonorrhoeae isolates, 445 (91.8%) were isolated from male urethritis subjects, and 77 (15.9%) were AZM-R (MIC ≥ 1 mg/L), including 33 (6.8%) with AZM low-level resistant (AZM-LLR, MIC = 1 mg/L) and 44 (9.1%) with AZM middle-level resistant (AZM-MLR, MIC ≥ 2 mg/L). Significantly more CRO(D) (MIC ≥ 0.125 mg/L) showed in AZM-MLR isolates (43.2%, 19/44) as compared with that in AZM-LLR isolates (18.2%, 6/33) (p < 0.05). For the 23S rRNA, mtrR, penA or combined 23S rRNA/MtrR/penA mutations, no significant difference was found between AZM-LLR isolates and AZM-MLR isolates (P > 0.05); similar results were detected between combined AZM-LLR/CRO(D) isolates and combined AZM-MLR/CRO(D) isolates (P > 0.05). No mutation A2059G or AZM high-level resistant (AZM-HLR, MIC ≥ 256 mg/L) isolate was detected. Among 77 AZM-R isolates, 67 sequence types (STs) were identified by NG-MAST, of which 30 were novel. Most STs were represented by a single isolate. CONCLUSIONS: The AZM-R together CRO(D) isolates are now present in Guangzhou, China, which deserve continuous surveillance and the mechanism of concurrent resistance needs further study.

Trends in antimicrobial resistance in Neisseria gonorrhoeae isolated from Guangzhou, China, 2000 to 2005 and 2008 to 2013.

A total of 1224 Neisseria gonorrhoeae isolates from Guangzhou in 2 periods (2000-2005 and 2008-2013) were subjected to antimicrobial susceptibility testing. The percentage of penicillin- and ciprofloxacin-resistant isolates increased from 71.1% (473/665) to 90.9% (508/559) and 88.9% (591/665) to 98.0% (548/559), respectively. All isolates remain susceptible to spectinomycin and ceftriaxone, with increasing minimum inhibitory concentrations.

Prenatal maternal vaginal inflammation increases anxiety and alters HPA axis signalling in adult male mice.

BACKGROUND: Maternal infection during pregnancy is known to adversely affect foetal development, but previous studies have rarely investigated the impact of gynaecological diseases during pregnancy on offspring during adulthood. Vaginitis is one of the most prevalent gynaecological diseases during pregnancy. METHODS: The effect of maternal vaginal inflammation on offspring was simulated by inducing maternal vaginal infection. We performed a transvaginal injection of lipopolysaccharide (LPS) in pregnant mice to induce vaginitis and investigated their offspring by means of behavioural tests and molecular and cellular measurements. RESULTS: Behavioural tests revealed that the offspring of mothers transvaginally injected with LPS exhibited sex-dependent differences. Male offspring showed increased anxiety-related behaviours, including reduced time exploring the open arm in the elevated plus maze test and light chamber in the light-dark box test. Serum levels of corticosterone were increased in LPS male offspring, indicating activation of the hypothalamic-pituitary-adrenal (HPA) axis. Corticotropin-releasing hormone (CRH) protein expression and c-Fos positive cells were increased in the hypothalamic paraventricular nucleus (PVN) in LPS male offspring, which presented with an increased number of microglia. CONCLUSION: This study suggests that prenatal vaginal infection increases anxiety-like behaviour in male offspring, possibly via activation of the HPA axis.

Treponemal antibody in CSF and cellular immunity in peripheral blood of syphilitic patients with persisting positive rapid plasma regain.

The ratio of patients with RPR constant positive more than 2 years despite receiving standard syphilis treatment has been reported to be 11.54%~31.3%. The current interpretations on this phenomenon are cellular immune function restrained and the existence of neurosyphilis or asymptomatic neurosyphilis. We conducted this study to detect the treponemal antibody in cerebrospinal fluid (CSF) and lymphocyte subsets in peripheral blood of syphilis patients with persisting RPR positive more than 2 years without neurologic signs, and then explore their relationship. In this study, Treponemal antibody in CSF of 46 syphilitic with HIV negative were measured by syphilis serum test and compared with that of 5 neurosyphilis. Lymphocyte subsets were measured by flow cytometry (FCM) and compared with that of 30 healthy controls. We observed that treponemal antibody in CSF was detected not only in 12 cases (25.21%) of 46 treated patients, but also in 5 neurosyphilis. The ratio of lymphocyte subsets revealed that CD3+, CD4+ T cells and natural killer (NK) cells showed no significant differences between the patient and healthy controls (P>0.05), while CD8+ T cells in patients were significant higher than that in healthy controls (P<0.001). Lymphocyte subsets showed no significant differences between the patients with treponemal antibody positive and negative in CSF (P>0.05). In conclusion, the treponemal antibody in CSF of treated patients suggests that part of them were asymptomatic neurosyphilis and with cellular immunodifeciency. And there is no significant relationship between asymptomatic neurosyphilis and cellular immunodeficiency in peripheral blood.

[Detection of peripheral blood lymphocyte subsets in treated syphilis patients with persistent positivity for rapid plasma reagin].

OBJECTIVE: To observe the changes in peripheral blood lymphocyte subsets in patients with latent syphilis after treatment, who had persistent positive results of test for rapid plasma reagin (RPR) and remained infectious. METHODS: T-lymphocyte subsets and natural killer (NK) cells in peripheral blood were measured with flow cytometry (FCM) in these 43 patients and 30 normal subjects served as controls. RESULTS: Peripheral blood CD3, CD4 and NK cells exhibited no significant difference between the latent patients and the controls (P>0.05), but CD8 cells were higher in these patients (P<0.05). The treated patients with persistent positive RPR within two years had elevated levels of CD3, CD4 and CD8 lymphocytes (P<0.05), but NK cells appeared to be lowered (P<0.05); in patients with positive RPR for over two years, CD3, CD4 and NK cells were comparable with those in the controls (P>0.05), but CD8 cells was elevated (P<0.05). Patients with RPR positivity within two years had higher CD3 and CD4 lymphocytes, but lower NK cells in comparison with the patients with more than two years' of positivity (P<0.05); CD8 cells were comparable between the two groups (P>0.05). CONCLUSIONS: Cellular immunity imbalance and immune suppression can be present in treated syphilis patients with persistent positive RPR and the risk to transmission, which may lower the host ability to resist and clear Treponema pallidum and is associated with the difficulty in treating syphilis patients and the persistence of positive RPR even after treatment.