Touchdown enzyme time release-PCR for detection and identification of Chlamydia trachomatis, C. pneumoniae, and C. psittaci using the 16S and 16S-23S spacer rRNA genes

Neisseria gonorrhoeae Infection in Women Increases With Rising Gonococcal Burdens in Partners: Chlamydia Coinfection in Women Increases Gonococcal Burden

BACKGROUND

Likelihood of Neisseria gonorrhoeae infection in women exposed to male sex partners with increasing N. gonorrhoeae burdens and enhancement by Chlamydia trachomatis is not defined.

METHODS

We identified men with urethritis and their regular female sex partners. Exposure to N. gonorrhoeae burdens in men was compared in N. gonorrhoeae-infected versus -uninfected partners. Association of N. gonorrhoeae infection in women with burdens in male partners was estimated using logistic regression. Association of C. trachomatis coinfection and N. gonorrhoeae burdens in women adjusted for burdens in male partners was estimated by linear regression.

RESULTS

In total, 1816 men were enrolled; 202 had ≥2 partners, 91 who confirmed monogamy and were enrolled; 77% were married. Seventy were partners of N. gonorrhoeae-infected men; 58 (83%) were N. gonorrhoeae infected, 26 (45%) C. trachomatis coinfected. Infected women had partners with 9.3-fold higher N. gonorrhoeae burdens than partners of uninfected women (P = .0041). Association of N. gonorrhoeae infection in women with upper quartiles of N. gonorrhoeae burdens in partners increased (odds ratios ≥ 2.97)compared to the first quartile (P = .032). N. gonorrhoeae burdens in C. trachomatis-coinfected women were 2.82-fold higher than in C. trachomatis-uninfected women (P = .036).

CONCLUSIONS

N. gonorrhoeae infections increased in women whose partners were infected with higher N. gonorrhoeae burdens. C. trachomatis coinfection was associated with increased N. gonorrhoeae burdens in women.

Fetoplacental pathology of equine abortion, premature birth, and neonatal loss due to Chlamydia psittaci

This report describes the fetoplacental pathology of Chlamydia psittaci-associated abortion, premature birth, and neonatal loss in 46 of 442 equine abortion investigations between 2015 and 2019. Seven abortions, 26 premature births, and 13 neonatal deaths with positive C. psittaci polymerase chain reaction (PCR) were evaluated. In 83% of cases (38/46), C. psittaci infection was considered as the primary cause of loss based on quantitative PCR (qPCR) confirmation, pathological findings, and exclusion of other causes, and was supported by Chlamydia spp immunolabeling in fetoplacental lesions. Lymphohistiocytic placentitis with vasculitis (36/38) affected the amnion, umbilical cord, and chorioallantois at the umbilical vessel insertion and/or cervical pole. Lymphohistiocytic chorionitis in the subvillous stroma extended to the allantois mostly without villous destruction. Lymphohistiocytic amnionitis and funisitis occurred at the amniotic cord attachment. Lymphohistiocytic hepatitis was observed in 19/38 cases and pneumonia was identified in 26 cases. Chlamydia spp immunolabeled in placenta, lung, liver, or splenic tissue in the cases that were tested (14/38). C. psittaci infection was not the cause of loss in 2 cases with other diseases and of uncertain significance in 6 cases with no conclusive cause of loss. immunohistochemistry (IHC) was negative for 6 of these cases (6/8). The highest Chlamydia load was detected in pooled placental tissues by qPCR. qPCR and IHC had 83% congruence at a qPCR cut-off of 1 gene copy. IHC limits of detection corresponded to infections with 2 × 10² gene copies identified by qPCR. This study confirms the etiological role of C. psittaci as a cause of naturally occurring equine reproductive loss.

Genotyping of Chlamydia abortus using multiple loci variable number of tandem repeats analysis technique

Background

The correlation between various factors (geographical region, clinical incidence, and host type) and the genomic heterogeneity has been shown in several bacterial strains including Chlamydia abortus.

Methods

The aim of this study was to survey the predominant types of C. abortus strains isolated from ruminants in Iran by the multiple loci variable number of tandem repeats (VNTR) analysis (MLVA) method. C. abortus infection was evaluated in a total of 117 aborted fetuses by real-time PCR. The isolation was done via the inoculation of the positive samples in chicken embryo and the L929 cell line. Genotyping was carried out by MLVA typing technique.

Results

Forty samples (34.2%) were detected with C. abortus infection; however, chlamydial infection in ruminants of Charmahal/Bakhtiari (3 bovines and 35 sheep) was higher than that of Khuzestan (2 sheep). All MLVA types (MT1-MT8) were detected in the collected samples from Charmahal/Bakhtiari but only 2 types (MT1 and MT3) were reported in samples from Khuzestan. The main MT type was MT1 (32% of aborted fetuses). Although in this study only 9 cow samples were investigated, they possessed similar clusters to those obtained from sheep (MT1 and MT6).

Variation of type in sheep samples (MT1 to MT8) was more than that of bovine samples (MT1, and MT6).

Conclusion

By this research revealed that C.abortus was responsible for a significant percentage of ruminant abortion in two studied regions. The main MT type was MT1 (32% of aborted fetuses) and also 7 different genotypes were involved in infections. So it is concluded that diversity in C.abortus genotyping is high in two regions.

Lack of Association between Chlamydophila psittaci and Ocular Adnexal MALT Lymphoma in Korean Patients-Is the Geographic or Genetic Difference Significant?

Clamydophila psittaci (C. psittaci) has been proposed to be an etiologic factor in extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) in the ocular adnexa. However, the pathogenetical significance of the infection has not been fully elucidated. Many previous studies have shown controversial results regarding C. psittaci detection rates in said patients, ranging from 0 to 87%. We investigated the presence of C. psittaci in a single institutional cohort (n = 150) of ocular adnexal MALT lymphoma (OAML) patients in Korea. We tried to exclude the methodological biases derived from the different primer sets in polymerase chain reaction-based studies. For that reason, we applied five sets of primers, including four previously reported and one newly designed primer set. There was no case of C. psittaci-positive OAML in repeated trials validated with appropriate positive and negative controls. All 150 cases showed negative results with five primer sets. These results suggest that the pathogenetic role of C. psittaci in ocular adnexal MALT lymphoma might have been overestimated to date, at least in the Korean population. Therefore, the molecular diagnosis of C. psittaci is considered a very low priority.

Real-time fluorometric and end-point colorimetric isothermal assays for detection of equine pathogens C. psittaci and equine herpes virus 1: validation, comparison and application at the point of care

Background

C. psittaci has recently emerged as an equine abortigenic pathogen causing significant losses to the Australian Thoroughbred industry, while Equine herpesvirus-1 (EHV-1) is a well-recognized abortigenic agent. Diagnosis of these agents is based on molecular assays in diagnostic laboratories.

In this study, we validated C. psittaci and newly developed EHV-1 Loop Mediated Isothermal Amplification (LAMP) assays performed in a real-time fluorometer (rtLAMP) against the reference diagnostic assays. We also evaluated isothermal amplification using commercially available colorimetric mix (cLAMP), and SYBR Green DNA binding dye (sgLAMP) for “naked eye” end-point detection when testing ‘real-world’ clinical samples. Finally, we applied the C. psittaci LAMP assays in two pilot Point-of-Care (POC) studies in an equine hospital.

Results

The analytical sensitivity of C. psittaci and EHV-1 rt-, and colorimetric LAMPs was determined as one and 10 genome equivalents per reaction, respectively. Compared to reference diagnostic qPCR assays, the C. psittaci rtLAMP showed sensitivity of 100%, specificity of 97.5, and 98.86% agreement, while EHV-1 rtLAMP showed 86.96% sensitivity, 100% specificity, and 91.43% agreement.

When testing rapidly processed clinical samples, all three C. psittaci rt-, c-, sg-LAMP assays were highly congruent with each other, with Kappa values of 0. 906 for sgLAMP and 0. 821 for cLAMP when compared to rtLAMP. EHV-1 testing also revealed high congruence between the assays, with Kappa values of 0.784 for cLAMP and 0.638 for sgLAMP when compared to rtLAMP. The congruence between LAMP assays and the C. psittaci or EHV-1 qPCR assays was high, with agreements ranging from 94.12 to 100% for C. psittaci, and 88.24 to 94.12% for EHV-1, respectively.

At the POC, the C. psittaci rt- and c-LAMP assays using rapidly processed swabs were performed by technicians with no prior molecular experience, and the overall congruence between the POC C. psittaci LAMPs and the qPCR assays ranged between 90.91–100%.

Conclusions

This study describes reliable POC options for the detection of the equine pathogens: C. psittaci and EHV-1. Testing ‘real-world’ samples in equine clinical setting, represents a proof-of-concept that POC isothermal diagnostics can be applied to rapid disease screening in the equine industry.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02986-8.

Development and evaluation of a novel quenching probe PCR (GENECUBE) assay for rapidly detecting and distinguishing between Chlamydia pneumoniae and Chlamydia psittaci

Early detection of the family Chlamydiaceae as pathogens is essential worldwide for the rapid and sufficient management of atypical pneumonia. GENECUBE (TOYOBO) is a novel fully automated gene analyzer capable of amplifying and detecting target DNAs within 50 min. In this study, we developed a new PCR assay with a specific quenching probe (PCR-QC assay) for rapidly distinguishing between Chlamydia pneumoniae (CPN) and Chlamydia psittaci (CPS). The PCR-QC assay enabled us to precisely and simultaneously detect the 2 different types of DNA fragments even in a mixed sample by identifying unique melting temperatures. Next, we examined a total of 300 frozen samples from patients with respiratory tract infection using the PCR-QC assay and the cell culture method as the gold standard. Kappa index for agreement between the PCR-QC assay and the culture method was 0.43 (95% confidential interval (CI): 0.08-0.78). The sensitivity and specificity of the PCR-QC assay were 36.3% (4/11; 95% CI: 10.9-69.2%)) and 99.0% (286/289; 95% CI: 97.0-99.8%), respectively. The samples positive for CPN (n = 13) or CPS (n = 1) by either method were also examined by a conventional PCR TaqMan assay, which produced the same results as those from the PCR-QC assay. Furthermore, the PCR-QC assay using GENECUBE shortened the full detection time for CPN or CPS (within 50 min vs. more than 2 to 3 h) compared with conventional PCR TaqMan assays. Therefore, the new PCR-QC assay system equipped with GENECUBE is useful for rapidly detecting CPN or CPS pathogens in clinical laboratory, and may improve the management of atypical pneumonia.

Isolation and Identification of Chlamydia abortus from Aborted Ewes in Sulaimani Province, Northern Iraq

Abortion in small ruminants is a significant problem in Iraq and causes severe economic losses in sheep farms. Chlamydia abortus causes enzootic abortion in ewes and is associated with reproductive problems in sheep in Sulaimani province – Northern Iraq. During a lambing season in 2017, abortion was widespread among several sheep flocks in different regions of Sulaimani (Kalar, Said Sadiq, and Chamchamal), and C. abortus was one of the causes. Accordingly, we carried out this study to isolate and identify C. abortus in aborted ewes in these regions. We collected 30 samples of aborted fetuses from five herds in which abortions had been observed. The pathogen isolation was done by inoculation into embryonated chicken eggs and conventional PCR was used to identify C. abortus in clinical specimens. C. abortus was identified in one of the 30 aborted fetuses (3.33%) from the Kalar district, and all the remaining 29 samples (96.66%) were found positive to Brucella abortus. The gene ompA encoding the outer membrane protein of C. abortus was sequenced and got the accession number MK643153 in NCBI GenBank. The sequence was named C. abortus strain Sul/2017. Our isolate showed 99.79% homology with Sul/014 (accession No. KY399850) and differed from the latter by two amino acid substitutions at E115K and K259N. The topology of the phylogenetic tree based on the ompA gene showed that the isolate belongs to C. abortus and has a common ancestor with isolates of sheep in Iraq and Tunisia with accession numbers KY399850 and HQ62243, respectively.

Chlamydia pneumoniae is present in the dental plaque of periodontitis patients and stimulates an inflammatory response in gingival epithelial cells

Chlamydia pneumoniae is an airborne, Gram-negative, obligate intracellular bacterium which causes human respiratory infections and has been associated with atherosclerosis. Because individuals with periodontitis are at greater risk for atherosclerosis as well as respiratory infections, we in-vestigated the role of C. pneumoniae in inflammation and periodontal dis-ease. We found that C. pneumoniae was more frequently found in subgingival dental plaque obtained from periodontally diseased sites of the mouth versus healthy sites. The known periodontal pathogens, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were also found in the plaque. In addition, C. pneumoniae could efficiently invade human gingival epithelial cells (GECs) in vitro, causing translocation of NF-κB to the nucleus along with increased secretion of mature IL-1β cytokine. Supernatants collected from C. pneumoniae-infected GECs showed increased activation of caspase-1 protein, which was significantly reduced when nlrp3 gene expression was silenced using shRNA lentiviral vectors. Our results demonstrate that C. pneumoniae was found in higher levels in periodontitis patients compared to control pa-tients. Additionally, C. pneumoniae could infect GECs, leading to inflammation caused by activation of NF-κB and the NLRP3 inflammasome. We propose that the presence of C. pneumoniae in subgingival dental plaque may contribute to periodontal disease and could be used as a potential risk indicator of perio-dontal disease.

An epizootic of Chlamydia psittaci equine reproductive loss associated with suspected spillover from native Australian parrots

Chlamydia psittaci is an avian pathogen capable of spill-over infections to humans. A parrot C. psittaci strain was recently detected in an equine reproductive loss case associated with a subsequent cluster of human C. psittaci infections. In this study, we screened for C. psittaci in cases of equine reproductive loss reported in regional New South Wales, Australia during the 2016 foaling season. C. psittaci specific-PCR screening of foetal and placental tissue samples from cases of equine abortion (n = 161) and foals with compromised health status (n = 38) revealed C. psittaci positivity of 21.1% and 23.7%, respectively. There was a statistically significant geographical clustering of cases ~170 km inland from the mid-coast of NSW (P < 0.001). Genomic analysis and molecular typing of C. psittaci positive samples from this study and the previous Australian equine index case revealed that the equine strains from different studs in regional NSW were clonal, while the phylogenetic analysis revealed that the C. psittaci strains from both Australian equine disease clusters belong to the parrot-associated 6BC clade, again indicative of spill-over of C. psittaci infections from native Australian parrots. The results of this work suggest that C. psittaci may be a more significant agent of equine reproductive loss than thought. A range of studies are now required to evaluate (a) the exact role that C. psittaci plays in equine reproductive loss; (b) the range of potential avian reservoirs and factors influencing infection spill-over; and (c) the risk that these equine infections pose to human health.

Anatomical site distribution and genotypes of Chlamydia trachomatis infecting asymptomatic men who have sex with men in northeast Thailand

Chlamydia trachomatis is a common agent of sexually transmitted infection, especially in asymptomatic extra-genital sites among men who have sex with men (MSM). This study aims to investigate anatomical site distribution and genotypes of C. trachomatis from asymptomatic MSM in northeast Thailand. Specimens were collected using swabs from anorectal, oropharyngeal, and urethral sites in 346 asymptomatic MSM. C. trachomatis infection was determined by real-time polymerase chain reaction and genotyping was based on sequences of the ompA gene. The results showed that infection by C. trachomatis was most common at the urethral site (29.1%, 101/346) followed by oropharyngeal (17.6%, 61/346) and anorectal site (17.0%, 59/346). In addition, C. trachomatis infection was significantly associated with absence of condom use (odds ratio = 1.909, 95%CI = 1.054-3.457, P = 0.033) at the urethral site. Overall 49.4% (171/346) of individuals were infected in at least one site. Infection at only the anorectum, oropharynx, or urethra was seen in 9.0, 9.3, and 18.5% of participants, respectively. Concurrent infections at anorectum/oropharynx, anorectum/urethra, oropharynx/urethra, and all three sites were 2.0, 4.3, 4.6, and 1.7%, respectively. Genotype D predominated at the anorectal and urethral sites among asymptomatic MSM in northeast Thailand. Concurrent infection in two or three anatomical sites occurred. C. trachomatis screening at all three sites in asymptomatic MSM is important and should be considered for proper treatment and prevention of transmission.

Genotype-Specific Concordance of Chlamydia trachomatis Genital Infection Within Heterosexual Partnerships

BACKGROUND

Sexual transmission rates of Chlamydia trachomatis (Ct) cannot be measured directly; however, the study of concordance of Ct infection in sexual partnerships (dyads) can help to illuminate factors influencing Ct transmission.

METHODS

Heterosexual men and women with Ct infection and their sex partners were enrolled and partner-specific coital and behavioral data collected for the prior 30 days. Microbiological data included Ct culture, and nucleic acid amplification testing (NAAT), quantitative Ct polymerase chain reaction, and ompA genotyping. We measured Ct concordance in dyads and factors (correlates) associated with concordance.

RESULTS

One hundred twenty-one women and 125 men formed 128 dyads. Overall, 72.9% of male partners of NAAT-positive women and 68.6% of female partners of NAAT-positive men were Ct-infected. Concordance was more common in dyads with culture-positive members (78.6% of male partners, 77% of female partners). Partners of women and men who were NAAT-positive only had lower concordance (33.3%, 46.4%, respectively). Women in concordant dyads had significantly higher median endocervical quantitative Ct polymerase chain reaction values (3,032) compared with CT-infected women in discordant dyads (1013 inclusion forming units DNA equivalents per mL; P < 0.01). Among 54 Ct-concordant dyads with ompA genotype data for both members, 96.2% had identical genotypes.

CONCLUSIONS

Higher organism load appears associated with concordance among women. Same-genotype chlamydial concordance was high in sexual partnerships. No behavioral factors were sufficiently discriminating to guide partner services activities. Findings may help model coitus-specific transmission probabilities.

The role of zoonotic chlamydial agents in ruminants abortion

BACKGROUND AND OBJECTIVES

Enzootic abortion of ewes (EAE) is caused by infection of sheep and goats by Chlamydia abortus bacterium. Chlamydial abortion in bovine could occur by Chlamydia abortus, Chlamydia psittaci and Chlamydia pecorum. C. psittaci is the causative agent of psittacosis or ornithosis disease in humans and birds. It also causes acute pneumonia in cattle and sheep. The present study aimed at surveying the role of chlamydial agents in ruminants abortion.

MATERIALS AND METHODS

A total of 117 aborted material samples (Cotyledon, liver, spleen, and abomasal contents of fetus) from 9 cattle and 100 sheep in Shahr-e-Kord and 8 sheep from Bagh-e-Malek were collected from different herds with abortion history during the lambing periods from 2014 to 2016. After DNA extraction, the samples were tested by species-specific PCR to detect C. abortus, C. pecorum and C. psittaci.

RESULTS

Out of 117 clinical sample (108 sheep and 9 cattle), chlamydial infection was detected in 66 (56.41%) samples by Chlamydiales order-specific primers. A total of 24 (36.36%) and 24 (36.36%) samples indicated positive forms of C. abortus and C. psittasi infections, respectively. Only 1 (1.5%) C. pecorum was identified from cattle using nested PCR during this study. Among 66 Chlamydiales-positive samples, 20 (30.30%) samples with coinfection of C. abortus and C. psittaci were detected, however, infection of 3 species was not detected in the samples.

CONCLUSION

Because of the high percentage of chlamydial infection in these regions and probability of coinfection, conducting epidemiological studies on the role of different animals is highly recommended.

Development and evaluation of rapid novel isothermal amplification assays for important veterinary pathogens: Chlamydia psittaci and Chlamydia pecorum

Background

Chlamydia psittaci and Chlamydia pecorum are important veterinary pathogens, with the former also being responsible for zoonoses, and the latter adversely affecting koala populations in Australia and livestock globally. The rapid detection of these organisms is still challenging, particularly at the point-of-care (POC). In the present study, we developed and evaluated rapid, sensitive and robust C. psittaci-specific and C. pecorum-specific Loop Mediated Isothermal Amplification (LAMP) assays for detection of these pathogens.

Methods and Materials

The LAMP assays, performed in a Genie III real-time fluorometer, targeted a 263 bp region of the C. psittaci-specific Cps_0607 gene or a 209 bp region of a C. pecorum-specific conserved gene CpecG_0573, and were evaluated using a range of samples previously screened using species-specific quantitative PCRs (qPCRs). Species-specificity for C. psittaci and C. pecorum LAMP targets was tested against DNA samples from related chlamydial species and a range of other bacteria. In order to evaluate pathogen detection in clinical samples, C. psittaci LAMP was evaluated using a total of 26 DNA extracts from clinical samples from equine and avian hosts, while for C. pecorum LAMP, we tested a total of 63 DNA extracts from clinical samples from koala, sheep and cattle hosts. A subset of 36 C. pecorum samples was also tested in a thermal cycler (instead of a real-time fluorometer) using newly developed LAMP and results were determined as an end point detection. We also evaluated rapid swab processing (without DNA extraction) to assess the robustness of these assays.

Results

Both LAMP assays were demonstrated to species-specific, highly reproducible and to be able to detect as little as 10 genome copy number/reaction, with a mean amplification time of 14 and 24 min for C. psittaci and C. pecorum, respectively. When testing clinical samples, the overall congruence between the newly developed LAMP assays and qPCR was 92.3% for C. psittaci (91.7% sensitivity and 92.9% specificity); and 84.1% for C. pecorum (90.6% sensitivity and 77.4% specificity). For a subset of 36 C. pecorum samples tested in a thermal cycler using newly developed LAMP, we observed 34/36 (94.4%) samples result being congruent between LAMP performed in fluorometer and in thermal cycler. Rapid swab processing method evaluated in this study also allows for chlamydial DNA detection using LAMP.

Discussion

In this study, we describe the development of novel, rapid and robust C. psittaci-specific and C. pecorum-specific LAMP assays that are able to detect these bacteria in clinical samples in either the laboratory or POC settings. With further development and a focus on the preparation of these assays at the POC, it is anticipated that both tests may fill an important niche in the repertoire of ancillary diagnostic tools available to clinicians.

An outbreak of psittacosis at a veterinary school demonstrating a novel source of infection

In November 2014, New South Wales Health was notified of a cluster of respiratory illness in a veterinary school. Active case finding identified another case at a local equine stud. All cases had exposure to the equine fetal membranes of Mare A. This tissue subsequently tested positive for Chlamydia psittaci using quantitative real-time polymerase chain reaction. We conducted a cohort study of the university and stud farm staff to determine risk factors for disease. Nine people were exposed to the fetal membranes of Mare A. Of these, five cases of psittacosis were identified. Two required hospital admission. Contact with birds was not associated with illness (RR = 0.5, 95% CI = 0.09-2.73). People who had direct contact with the abnormal fetal membranes were more likely to develop disease (RR = 11.77, 95% CI = 1.02-∞). The emergence of an association between horse exposure and C. psittaci infection has important implications for the prevention and control of psittacosis. Article summary line: Investigation of an outbreak of psittacosis in a rural veterinary school demonstrates novel source of infection for psittacosis through exposure to abnormal equine fetal membranes.

Evaluation of Chlamydophila Abortus DNA Extraction Protocols for Polymerase Chain Reaction Diagnosis in Paraffin-Embedded Tissues

Polymerase chain reaction (PCR) has gained increasing importance as a tool for directly demonstrating the presence of Chlamydophila in the placentas of aborted sheep and goats. However, because of the zoonotic potential of the disease, it is advisable to use fixed materials. To evaluate 4 different DNA extraction protocols in paraffin-embedded sections for PCR, previously immunohistochemically diagnosed placental samples from outbreaks of abortions in goats and sheep were used. The samples were also used to evaluate the effect of the duration of fixation in formalin on PCR. A protocol that uses Tris-HCl pH 8.5 with EDTA and subsequent digestion with proteinase K was found to be an easy protocol for obtaining excellent PCR products for Chlamydophila abortus diagnosis from formalin-fixed and paraffin-embedded specimens. It was also found that if samples are fixed in formalin for more than 2 weeks, the PCR technique is affected more adversely than immunohistochemical methods.

Chlamydia and ocular adnexal lymphomas: An Indian experience

CHLAMYDIA AND OCULAR ADNEXAL LYMPHOMAS

AN INDIAN EXPERIENCE: Ocular adnexal lymphomas (OALs) are a heterogeneous group of malignancies, majority being extranodal mucosa-associated lymphoid tissue (MALT) type. Different geographical regions have reported association of Chlamydia with OALs (MALT type). In India, role of Chlamydia in OALs remains unexplored. The aim of this study was to detect Chlamydia and to correlate with clinicopathological features of OALs in India. The clinicopathological features of 41 OAL cases were studied prospectively. Chlamydia DNA was detected by genus specific PCR amplifying major outer membrane protein (MOMP) gene followed by DNA sequencing. Chlamydia immunoexpression was evaluated by immunofluorescence and immunohistochemistry. The results were correlated with clinicopathological features including follow-up and survival. Chlamydia genome was detected in 3/41 (7.3%) OAL cases by PCR. Direct sequencing revealed C. trachomatis in 3 positive cases. Immunofluorescence and immunohistochemistry showed Chlamydia antigen in 5/41 and 1/41 cases respectively. Immunofluorescence demonstrated higher sensitivity than immunohistochemistry. A significant association was observed between Chlamydia positivity and orbital location (P=0.05). Follow-up revealed relapse in 2 Chlamydia positive cases (P=0.056). Our results demonstrate for the first time presence of C. trachomatis genome in 7.3% OAL cases in India. As no other reports are documented, more detailed studies from different regions within India are needed to explore status of Chlamydia in OALs.

The Gonococcal Transcriptome during Infection of the Lower Genital Tract in Women

Gonorrhea is a highly prevalent disease resulting in significant morbidity worldwide, with an estimated 10⁶ cases reported annually. Neisseria gonorrhoeae, the causative agent of gonorrhea, colonizes and infects the human genital tract and often evades host immune mechanisms until successful antibiotic treatment is used. The alarming increase in antibiotic-resistant strains of N. gonorrhoeae, the often asymptomatic nature of this disease in women and the lack of a vaccine directed at crucial virulence determinants have prompted us to perform transcriptome analysis to understand gonococcal gene expression patterns during natural infection. We sequenced RNA extracted from cervico-vaginal lavage samples collected from women recently exposed to infected male partners and determined the complete N. gonorrhoeae transcriptome during infection of the lower genital tract in women. On average, 3.19% of total RNA isolated from female samples aligned to the N. gonorrhoeae NCCP11945 genome and 1750 gonococcal ORFs (65% of all protein-coding genes) were transcribed. High expression in vivo was observed in genes encoding antimicrobial efflux pumps, iron response, phage production, pilin structure, outer membrane structures and hypothetical proteins. A parallel analysis was performed using the same strains grown in vitro in a chemically defined media (CDM). A total of 140 genes were increased in expression during natural infection compared to growth in CDM, and 165 genes were decreased in expression. Large differences were found in gene expression profiles under each condition, particularly with genes involved in DNA and RNA processing, iron, transposase, pilin and lipoproteins. We specifically interrogated genes encoding DNA binding regulators and iron-scavenging proteins, and identified increased expression of several iron-regulated genes, including tbpAB and fbpAB, during infection in women as compared to growth in vitro, suggesting that during infection of the genital tract in women, the gonococcus is exposed to an iron deplete environment. Collectively, we demonstrate that a large portion of the gonococcal genome is expressed and regulated during mucosal infection including genes involved in regulatory functions and iron scavenging.

In contrast to Chlamydia trachomatis, Waddlia chondrophila grows in human cells without inhibiting apoptosis, fragmenting the Golgi apparatus, or diverting post-Golgi sphingomyelin transport

The Chlamydiales are an order of obligate intracellular bacteria sharing a developmental cycle inside a cytosolic vacuole, with very diverse natural hosts, from amoebae to mammals. The clinically most important species is Chlamydia trachomatis. Many uncertainties remain as to how Chlamydia organizes its intracellular development and replication. The discovery of new Chlamydiales species from other families permits the comparative analysis of cell-biological events and may indicate events that are common to all or peculiar to some species and more or less tightly linked to "chlamydial" development. We used this approach in the infection of human cells with Waddlia chondrophila, a species from the family Waddliaceae whose natural host is uncertain. Compared to C. trachomatis, W. chondrophila had slightly different growth characteristics, including faster cytotoxicity. The embedding in cytoskeletal structures was not as pronounced as for the C. trachomatis inclusion. C. trachomatis infection generates proteolytic activity by the protease Chlamydia protease-like activity factor (CPAF), which degrades host substrates upon extraction; these substrates were not cleaved in the case of W. chondrophila. Unlike Chlamydia, W. chondrophila did not protect against staurosporine-induced apoptosis. C. trachomatis infection causes Golgi apparatus fragmentation and redirects post-Golgi sphingomyelin transport to the inclusion; both were absent from W. chondrophila-infected cells. When host cells were infected with both species, growth of both species was reduced. This study highlights differences between bacterial species that both depend on obligate intracellular replication inside an inclusion. Some features seem principally dispensable for intracellular development of Chlamydiales in vitro but may be linked to host adaptation of Chlamydia and the higher virulence of C. trachomatis.

Synergistic Costimulatory Effect of Chlamydia pneumoniae with Carbon Nanoparticles on NLRP3 Inflammasome-Mediated Interleukin-1β Secretion in Macrophages

The obligate intracellular bacterium Chlamydia pneumoniae is not only a causative agent of community-acquired pneumonia but is also associated with a more serious chronic disease, asthma, which might be exacerbated by air pollution containing carbon nanoparticles. Although a detailed mechanism of exacerbation remains unknown, the proinflammatory cytokine interleukin-1β (IL-1β) is a critical player in the pathogenesis of asthma. C. pneumoniae induces IL-1β in macrophages via NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome activation and Toll-like receptor 2/4 (TLR2/4) stimulation. Carbon nanoparticles, such as carbon nanotubes (CNTs), can also evoke the NLRP3 inflammasome to trigger IL-1β secretion from lipopolysaccharide-primed macrophages. This study assessed whether costimulation of C. pneumoniae with CNTs synergistically enhanced IL-1β secretion from macrophages, and determined the molecular mechanism involved. Enhanced IL-1β secretion from C. pneumoniae-infected macrophages by CNTs was dose and time dependent. Transmission electron microscopy revealed that C. pneumoniae and CNTs were engulfed concurrently by macrophages. Inhibitors of actin polymerization or caspase-1, a component of the inflammasome, significantly blocked IL-1β secretion. Gene silencing using small interfering RNA (siRNA) targeting the NLRP3 gene also abolished IL-1β secretion. Other inhibitors (K(+) efflux inhibitor, cathepsin B inhibitor, and reactive oxygen species-generating inhibitor) also blocked IL-1β secretion. Taken together, these findings demonstrated that CNTs synergistically enhanced IL-1β secretion from C. pneumoniae-infected macrophages via the NLRP3 inflammasome and caspase-1 activation, providing novel insight into our understanding of how C. pneumoniae infection can exacerbate asthma.

Emendation of the family Chlamydiaceae: proposal of a single genus, Chlamydia, to include all currently recognized species

The family Chlamydiaceae (order Chlamydiales, phylum Chlamydiae) comprises important, obligate intracellular bacterial pathogens of humans and animals. Subdivision of the family into the two genera Chlamydia and Chlamydophila has been discussed controversially during the past decade. Here, we have revisited the current classification in the light of recent genomic data and in the context of the unique biological properties of these microorganisms. We conclude that neither generally used 16S rRNA sequence identity cut-off values nor parameters based on genomic similarity consistently separate the two genera. Notably, no easily recognizable phenotype such as host preference or tissue tropism is available that would support a subdivision. In addition, the genus Chlamydophila is currently not well accepted and not used by a majority of research groups in the field. Therefore, we propose the classification of all 11 currently recognized Chlamydiaceae species in a single genus, the genus Chlamydia. Finally, we provide emended descriptions of the family Chlamydiaceae, the genus Chlamydia, as well as the species Chlamydia abortus, Chlamydia caviae and Chlamydia felis.

B-cell epitopes in GroEL of Francisella tularensis

The chaperonin protein GroEL, also known as heat shock protein 60 (Hsp60), is a prominent antigen in the human and mouse antibody response to the facultative intracellular bacterium Francisella tularensis (Ft), the causative agent of tularemia. In addition to its presumed cytoplasmic location, FtGroEL has been reported to be a potential component of the bacterial surface and to be released from the bacteria. In the current study, 13 IgG2a and one IgG3 mouse monoclonal antibodies (mAbs) specific for FtGroEL were classified into eleven unique groups based on shared VH-VL germline genes, and seven crossblocking profiles revealing at least three non-overlapping epitope areas in competition ELISA. In a mouse model of respiratory tularemia with the highly pathogenic Ft type A strain SchuS4, the Ab64 and N200 IgG2a mAbs, which block each other’s binding to and are sensitive to the same two point mutations in FtGroEL, reduced bacterial burden indicating that they target protective GroEL B-cell epitopes. The Ab64 and N200 epitopes, as well as those of three other mAbs with different crossblocking profiles, Ab53, N3, and N30, were mapped by hydrogen/deuterium exchange–mass spectrometry (DXMS) and visualized on a homology model of FtGroEL. This model was further supported by its experimentally-validated computational docking to the X-ray crystal structures of Ab64 and Ab53 Fabs. The structural analysis and DXMS profiles of the Ab64 and N200 mAbs suggest that their protective effects may be due to induction or stabilization of a conformational change in FtGroEL.

Could urine be useful for the diagnosis of Chlamydia trachomatis pneumonia in infancy?

A 9-week-old infant presented with respiratory distress. The presumptive diagnosis of Chlamydia trachomatis pneumonia was ultimately made in a novel manner by a positive nucleic acid amplification test on a urine sample.

Clinical features of endemic community-acquired psittacosis

Following a large outbreak of community-acquired psittacosis in 2002 in residents of the Blue Mountains, New South Wales, Australia, we reviewed new cases in this area over a 7-year period from 2003 to 2009. Using the 2010 criteria from the Centers for Disease Control National Notifiable Diseases Surveillance System, 85 patients with possible psittacosis were identified, of which 48 were identified as definite or probable infection. Clinical features of these cases are summarized. In addition to Chlamydia-specific serology, specimens, where available, underwent nucleic acid testing for chlamydial DNA using real-time PCR. Chlamydophila psittaci DNA was detected in samples from 23 patients. Four of 18 specimens were culture positive. This is the first description of endemic psittacosis, and is characterized in this location by community-acquired psittacosis resulting from inadvertent exposure to birds. The disease is likely to be under-diagnosed, and may often be mistaken for gastroenteritis or meningitis given the frequency of non-respiratory symptoms, particularly without a history of contact with birds. Clinical characteristics of endemic and outbreak-associated cases were similar. The nature of exposure, risk factors and reasons for the occurrence of outbreaks of psittacosis require further investigation.

Comparison of Five PCR Assays for DetectingChlamydophila pneumoniaeDNA

We compared five different polymerase chain reaction (PCR) assays for the detection of Chlamydophila pneumoniae DNA using highly purified elementary bodies (EBs) and peripheral blood mononuclear cells (PBMCs) from healthy blood donors. The primers were as follows; two targeting the 16S rRNA gene, one targeting the ompA gene, one targeting the Pst-I gene, and one targeting the 53 kDa outer membrane protein gene. The 16S rRNA touchdown enzyme time release (TETR) PCR, the ompA nested PCR and the 53 kDa nested PCR were the most sensitive assays and could detect one or more EB per assay. These three PCRs also had the same reproducibility, but the minimal amount of C. pneumoniae that could be reproducibly detected (10 of 10 testing positive) was 20 EBs. In a sample of specimens from healthy blood donors, we found 5 of 77 (6.5%) PBMCs specimens to have C. pneumoniae DNA according to the nested ompA PCR. Specimens with the 16S rRNA TETR and 53 kDa nested assays were found to have C. pneumoniae DNA 7 of 77 (9.1%) and 18 of 77 (23.4%) specimens, respectively. The other two assays failed to detect even a single positive. However, the detection rate decreased with repeated testing of the same samples. Our newly designed 53 kDa nested PCR may be as useful as the other four recommended PCR assays and may be a more useful assay for the detection of C. pneumoniae DNA from PBMCs.

What is the role of newer molecular tests in the management of CAP?

Community-acquired pneumonia (CAP) accounts for major morbidity and mortality in the United States. With improved broad-spectrum antibiotics, the implementation of diagnostic studies has declined and most patients do not have an etiologic pathogen of CAP identified. To enhance the appropriate use of antiviral agents and prevent overuse of antibiotics, the successful management of CAP requires rapid and accurate diagnosis of the etiologic agent of CAP. This article provides an overview of the new rapid molecular tests for the diagnosis of influenza, other respiratory viruses, and bacteria compared with nonmolecular tests and how their use for directed therapy can enhance and improve the management of CAP.

Antibiotic therapy in nongastrointestinal MALT lymphoma: a review of the literature

Although antibiotic therapy has been established as the standard of care in patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, much less is known about the value of antibiotic therapy in nongastrointestinal (non-GI) MALT lymphomas. A computerized search (Medline) accompanied by a manual search to identify clinical reports on the topic of antibacterial therapy in patients with non-GI MALT lymphomas was performed. The majority of data were available for MALT lymphoma of the ocular adnexa (OAML) including a total of 131 patients in 4 retrospective studies, 3 prospective series (including 81 patients), and 1 case report. Treatment was exclusively targeting Chlamydophila psittaci (CP), using doxycycline in all but 2 studies. The median follow-up for these studies was 25 months, and both CP-positive as well as CP-negative patients responded. Complete remission was achieved in 23 patients (18%), 36 (27%) had a partial remission, 55 (42%) had stable disease, and 8 patients (6%) had progressive disease accounting for an overall response rate of 45%. In the largest study, a better response was suggested in CP-positive patients. By contrast, only scattered reports could be found for other non-GI localizations, allowing no conclusion about the benefit of antibiotic therapy and probably resulting in a publication bias toward positive cases. Based on these results, antibiotic therapy using doxycycline appears to be a reasonable first-line therapy for patients with OAML. Antibiotics, however, remain experimental for the time being in patients with other non-GI MALT lymphomas. Further preclinical studies as well as large-scale therapeutic trials are warranted to define the role of antibiotic therapy in such patients.

[Microbiological diagnosis of infections due to Chlamydia spp. and related species]

Until recently the number of completed genomes belonging to Chlamydia trachomatis was very low, despite its importance in Public Health. Now, there are currently sixty-six completed genomes of C.trachomatis sequenced in different parts of the world. This genomic revolution has helped in understanding its biology, as well as improved the sensitivity and specificity in the diagnosis, and the development of epidemiological tools, not only for in C.trachomatis, but also for related species such as C.pneumoniae and C.psittaci. The diagnosis based on cell culture, serology and microimmunofluorescence is gradually being replaced by molecular techniques based on PCR or real-time PCR. This is because these molecular tests do not have cross-reactions problems and the procedures are easily standardised between laboratories. Moreover, molecular epidemiology tools described recently, such as Multi-Locus Sequence Typing (MLST) and Variable Number Tandem Repeat (VNTR), have increased our knowledge on local and global epidemiology. This article focuses on the impact of the genomics advances achieved over the last few years as applied to the diagnosis, epidemiology and biology of the family Chlamydiaceae family and related species.

Chlamydophila psittaci eradication with doxycycline as first-line targeted therapy for ocular adnexae lymphoma: final results of an international phase II trial

PURPOSE

The pathogenic association between Chlamydophila psittaci (Cp) and ocular adnexal marginal zone lymphoma (OAMZL) and the efficacy of doxycycline monotherapy have been investigated in retrospective series with variations in stage, management, and follow-up duration. To our knowledge, this is the first international phase II trial aimed at clarifying Cp prevalence and activity of first-line doxycycline in a homogeneous series of consecutive patients with newly diagnosed stage I OAMZL.

PATIENTS AND METHODS

Forty-seven patients were registered. Tumor tissue, conjunctival swabs, and peripheral blood from 44 patients were assessed for seven Chlamydiaceae infections by three polymerase chain reaction protocols. Thirty-four patients with measurable or parametrable disease were treated with doxycycline and assessed for chlamydial eradication and lymphoma response (primary end point).

RESULTS

Cp DNA was detected in biopsies of 39 patients (89%); no other Chlamydiaceae were detected. Twenty-nine patients had Cp DNA in baseline swabs and/or blood samples and were evaluable for chlamydial eradication, which was achieved in 14 patients (48%). Lymphoma regression was complete in six patients and partial in 16 (overall response rate, 65%; 95% CI, 49% to 81%); 11 had stable disease, and one had progressive disease. At a median follow-up of 37 months (range, 15 to 62 months), 20 patients remained relapse free (5-year progression-free survival [PFS] ± standard deviation, 55% ± 9%). Cp eradication was associated with improved response rate (86% v 47%; P = .02) and 5-year PFS (68% v 47%; P = .11).

CONCLUSION

Upfront doxycycline is a rational and active treatment for patients with stage I Cp-positive OAMZL. Lymphoma regression is consequent to Cp eradication, which can easily be monitored on conjunctival and blood samples. Prospective trials aimed at identifying more effective administration schedules for doxycycline are warranted.

Lack of association of conjunctival MALT lymphoma with Chlamydiae or Helicobacter pylori in a cohort of Chinese patients

BACKGROUND

This study was conducted to detect microbial pathogens in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma specimens in an attempt to determine possible associations between conjunctival MALT lymphoma and microbial infections.

MATERIAL/METHODS

Using PCR technique, freshly obtained tumor specimens from 16 cases of conjunctival MALT lymphoma, as confirmed by postoperative pathology, were analyzed for DNA of Chlamydia psittaci (C. psittaci), Chlamydia trachomatis (C. trachomatis), Chlamydia pneumoniae (C. pneumoniae) and Helicobacter pylori (H. pylori). Synthetic C. psittaci, C. trachomatis, C. pneumoniae and H. pylori DNA were used as positive control, and blank plasmid DNA as negative control.

RESULTS

Electrophoresis showed that no bands corresponding to the positive control were observed in the specimens, indicating that no DNA of the 4 microorganisms was detected in the specimens of the 16 cases of conjunctival MALT lymphoma.

CONCLUSIONS

The PCR technique was able to detect the positive control quickly and accurately, but the results of PCR in analyzing the 16 specimens were negative, indicating that there is no association between conjunctival MALT lymphoma and the 4 microorganisms in Chinese patients.

Increased prevalence of Chlamydophila DNA in post-mortem brain frontal cortex from patients with schizophrenia

Infection can initiate symptoms of mental illness. It has been shown previously that Chlamydophila DNA is present six times more often in the blood of patients with schizophrenia than in the blood of control individuals. Monocytes, the main targets of Chlamydiaceae infection, are microglia precursors. We identified Chlamydiaceae infection using blinded brain DNA samples derived from the frontal cortex. Using PCR and sequence analysis, we found Chlamydophila DNA to be four times greater in patients with schizophrenia than in controls (schizophrenia: N=34, microbial DNA frequency 23.5%; controls: N=35, microbial DNA frequency 5.7%; P=0.045, OR=5.08). Persistent Chlamydophila-infected microglia or neuronal cells may impair neuronal circuits and thus be a mechanism for causing psychiatric illness in these patients.

Chlamydophila pneumoniae attachment and infection in low proteoglycan expressing human lymphoid Jurkat cells

This study investigated the proteoglycan (PG)-dependent mechanism of Chlamydophila pneumoniae attachment to lymphocytic cells. Lymphoid Jurkat cells and epithelial HEp-2 cells were statically infected with C. pneumoniae (TW183). Transmission electron microscopy and assessment of inclusion-forming units indicated that the bacteria grew normally in Jurkat cells and were capable of producing secondary infection; however, they grew at a slower rate than in HEp-2 cells. RT-PCR analysis indicated that HEp-2 cells strongly expressed PG-core protein encoding genes, thereby sustaining glycosaminoglycans (GAGs), such as heparin, on the cellular surface. Similar gene expression levels were not observed in Jurkat cells, with the exception of glypican-1. Immunofluorescence analysis also supported strong heparin expression in HEp-2 cells and minimal expression in Jurkat cells, although heparan sulfate pretreatment significantly inhibited bacterial attachment to both cell types. Immunofluorescent co-staining with antibodies against chlamydial LPS and heparin did not identify bacterial and heparin co-localization on Jurkat cells. We also confirmed that when C. pneumoniae was statically infected to human CD4(+) peripheral blood lymphocytes known not expressing detectable level of heparin, the bacteria attached to and formed inclusion bodies in the cells. Thus, the attachment mechanism of C. pneumoniae to Jurkat cells with low PG expression is unique when compared with HEp-2 cells and potentially independent of GAGs such as heparin.

Chlamydia psittaci Infection in nongastrointestinal extranodal MALT lymphomas and their precursor lesions

Extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) are associated with various infectious pathogens. We analyzed the presence of Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis DNA in 47 nongastrointestinal and 14 gastrointestinal MALT lymphomas, 37 nonmalignant control samples, and 27 autoimmune precursor lesions by polymerase chain reaction amplification and direct sequencing. In 47 nongastrointestinal MALT lymphomas, 13 (28%) were positive for C psittaci DNA compared with 4 (11%) of 37 nonmalignant control samples (P = .09). C psittaci was detected at variable frequencies in MALT lymphomas of different sites: lung, 100% (5/5; P < .01); thyroid gland, 30% (3/10; P > .05); salivary gland, 13% (2/15; P > .05); ocular adnexa, 15% (2/13); and skin, 25% (1/4). Of 27 autoimmune precursor lesions (11 Hashimoto thyroiditis and 16 Sjögren syndrome), 11 (41%) contained C psittaci DNA. Only 1 (7%) of 14 gastrointestinal MALT lymphomas was positive for C psittaci. All specimens were negative for C trachomatis and C pneumoniae. Besides ocular adnexal lymphomas, C psittaci infection is associated with nongastrointestinal MALT lymphomas and autoimmune precursor lesions, suggesting possible involvement of C psittaci-induced antigenic-driven MALT lymphomagenesis.

Ocular adnexal mucosa-associated lymphoid tissue lymphoma in Northern China: high frequency of numerical chromosomal changes and no evidence of an association with Chlamydia psittaci

Studies from different countries showed variations of genetic changes and association with Chlamydia psittaci in ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma. A total of 38 ocular adnexal MALT lymphoma cases from Northern China were studied. Genetic abnormalities were investigated in 28 cases by interphase FISH. C. psittaci and other infectious agents that are commonly-associated with chronic eye disease were screened in 38 cases by PCR. Genetic abnormalities were detected in 60.7% of cases. Among them, only one showed a break-apart of the IgH gene and all others showed numerical abnormalities, including trisomy 18 in 7 cases (25%), 3 copies of BCL6 gene in 12 cases (43%), and 3 copies of C-MYC gene in 2 cases (7%). C. pneumoniae was positive in two cases (5.3%), and C. psittaci, C. trachomatis, HSV1, HSV2, ADV8, and ADV19 were not detected in any cases. In conclusion, numerical abnormalities are frequent and the chromosomal translocations commonly associated with MALT lymphomas are rare in ocular adnexal MALT lymphoma of Northern China. C. psittaci and other infectious agents are not associated with ocular adnexal MALT lymphoma in these patients.

Isolation of Chlamydia pneumoniae from serum samples of the patients with acute coronary syndrome

BACKGROUND

Limited body of evidence suggests that lipopolysaccharide of C. pneumoniae as well as C. pneumoniae-specific immune complexes can be detected and isolated from human serum. The aim of this study was to investigate the presence of viable elementary bodies of C.pneumoniae in serum samples of patients with acute coronary syndrome and healthy volunteers.

MATERIAL AND METHODS

Serum specimens from 26 healthy volunteers and 56 patients with acute coronary syndrome were examined subsequently by serological (C.pneumoniae-specific IgA and IgG), PCR-based and bacteriological methods. Conventional, nested and TaqMan PCR were used to detect C.pneumoniae genetic markers (ompA and 16S rRNA) in DNA from serum specimens extracted with different methods. An alternative protocol which included culturing high-speed serum sediments in HL cells and further C.pneumoniae growth evaluation with immunofluorescence analysis and TaqMan PCR was established. Pellet fraction of PCR-positive serum specimens was also examined by immunoelectron microscopy.

RESULTS

Best efficiency of final PCR product recovery from serum specimens has been shown with specific C. pneumoniae primers using phenol-chloroform DNA extraction protocol. TaqMan PCR analysis revealed that human serum of patients with acute coronary syndrome may contain genetic markers of C. pneumoniae with bacterial load range from 200 to 2000 copies/ml serum. However, reliability and reproducibility of TaqMan PCR were poor for serum specimens with low bacterial copy number (<200 /ml). Combination of bacteriological, immunofluorescence and PCR- based protocols applied for the evaluating HL cells infected with serum sediments revealed that 21.0 % of the patients with acute coronary syndrome have viable forms C.pneumoniae in serum. The detection rate of C.pneumoniae in healthy volunteers was much lower (7.7%). Immunological profile of the patients did not match accurately C.pneumoniae detection rate in serum specimens. Elementary bodies of C.pneumoniae with typical ultrastructural characteristics were also identified in serum sediments using immunoelectron microscopy.

CONCLUSIONS

Viable forms C. pneumoniae with typical electron microscopic structure can be identified and isolated from serum specimens of the patients with acute coronary syndrome and some healthy volunteers. Increased detection rate of C. pneumoniae in serum among the patients with an acute coronary syndrome may contribute towards enhanced pro-inflammatory status in cardiovascular patients and development of secondary complications of atherosclerosis.

Chlamydophila pneumoniae

Chlamydophila pneumoniae is estimated to cause about 10% of community-acquired pneumonia (CAP) cases and 5% of bronchitis cases, although most patients with C pneumoniae infection are asymptomatic, and the course of respiratory illness is relatively mild. The incubation period of C pneumoniae infection is around 21 days, and such symptoms as cough and malaise show a gradual onset, yet may persist for several weeks or months despite appropriate antibiotic therapy. Diagnosis by nasopharyngeal specimen culture, serum antibody titers, or molecular techniques is usually delayed with respect to the onset of symptoms, antibiotic treatment, or disease resolution and there is no accurate, standardized, commercial US Food and Drug Administration-cleared diagnostic method available. Erythromycin, tetracycline, and doxycycline are used as first-line therapy, although some investigators report no clinical or survival benefits from treating CAP caused by atypical pathogens. Meanwhile, adequate prospective studies have met with ethical and logistic barriers. Despite these limitations, North American guidelines recommend the antimicrobial treatment of patients with acute C pneumoniae respiratory infection.

First-line therapy with doxycycline in ocular adnexal mucosa-associated lymphoid tissue lymphoma: a retrospective analysis of clinical predictors

This retrospective study was launched to evaluate the efficacy of doxycycline and to find independent predictors of a clinical response in patients with ocular adnexal lymphoma of mucosa-associated lymphoid tissue (OAML). Thirty-eight patients with newly diagnosed, localized OAML received doxycycline for 3 weeks (12 patients) or 6 weeks (26 patients). Clinical factors including absolute lymphocyte count (ALC) and neutrophil count (ANC) were compared between responders and non-responders. After a median follow-up of 26.4 months, doxycycline resulted in an overall response rate of 47% and a 3-year time-to-treatment failure (TTF) rate of 84%. Patients treated with doxycycline for 6 weeks versus 3 weeks tended to have a higher response rate (54%vs 33%). Absolute lymphocytosis (ALC > 3.01 x 10(9)/L) and absolute neutrophilia (ANC > 1.92 x 10(9)/L) were defined based on the median value of each count. Patients with (19 patients) versus without absolute lymphocytosis had significantly shorter 2-year TTF (70%vs 100%, P = 0.021) and a lower response rate (32%vs 63%, P = 0.051). Absolute lymphocytosis (odds ratio [OR] = 4.7; 95% confidence interval [CI], 1.1-20.8; P = 0.043) and non-conjunctival tumor (OR = 11.8; 95% CI, 1.1-122.5; P = 0.038) were negative predictors for response by multivariate analysis. Front-line doxycycline is effective particularly in localized OAML patients without absolute lymphocytosis but with conjunctival involvement.

Geographic variation and environmental conditions as cofactors in Chlamydia psittaci association with ocular adnexal lymphomas: a comparison between Italian and African samples

A particular extra-nodal lymphoma type arises from B cells of the marginal zone (MZ) of mucosa-associated lymphoid tissue (MALT). The aetiology of MZ lymphomas suggests that they are associated with chronic antigenic stimulation by microbial pathogens, among which Helicobacter pylori-associated gastric MALT lymphoma is the best studied. Recently, MALT lymphomas have been described in the context of chronic conjunctivitis, which can be associated with Chlamydia spp. infection. Studies from Italy showed the presence of Chlamydia psittaci in 87% of ocular adnexal lymphomas (OAL), and C. psittaci has been described in a large part of samples from Austria and Korea as well. However, this finding was not always confirmed by other studies, suggesting that the association with C. psittaci may depend on geographic heterogeneity. Interestingly, none of the studies up to now has been carried out in the African population, where a strong association between infectious agents and the occurrence of human neoplasms has been reported. This study was designed to investigate the possible association of Chlamydia psittaci in cases retrieved from Kenya, compared to cases from Italy. Our results showed that there was a marked variation between the two geographical areas in terms of association with C. psittaci, as 17% (5/30) of the samples from Italy were positive for C. psittaci, whereas no association with this pathogen was observed in any of the African samples (0/9), suggesting that other cofactors may determine the OAL occurrence in those areas. OAL cases are often characterized by down-regulation of p16/INK4a expression and promoter hypermethylation of the p16/INK4a gene. Our results showed a partial methylation of p16/INK4a promoter in C. psittaci-negative cases, whereas no hypermethylation of this gene was found in C. psittaci-positive cases, suggesting that mechanisms other than promoter hypermethylation lead to p16/INK4a silencing in C. psittaci-positive cases. We may conclude that the role of epidemiologic, environmental and genetic factors, must be considered in the aetiology of this disease.

Chlamydial infection: the link with ocular adnexal lymphomas

Chlamydiae are obligate intracellular bacteria that grow in eukaryotic cells and cause a wide spectrum of diseases. They can establish persistent infections, are mitogenic in vitro, promote polyclonal cell proliferation in vivo and induce resistance to apoptosis in infected cells-properties that might contribute to tumorigenesis. In fact, Chlamydophila psittaci (Cp) has been linked to the development and maintenance of ocular adnexal marginal zone B-cell lymphoma (OAMZL). In this indolent malignancy, Cp is transported by monocytes and macrophages and causes both local and systemic infection. Cp elementary bodies are viable and infectious in the conjunctiva and peripheral blood of patients with OAMZL. Bacterial eradication with antibiotic therapy is often followed by lymphoma regression. Despite recent advances in the understanding of this bacterium-lymphoma association, several questions remain unanswered. For instance, prevalence variations among different geographical areas and related diagnostic and therapeutic implications remain a major investigational issue. We will focus on clinical and therapeutic implications of chlamydial infections in patients with lymphomas and summarize the current knowledge on the association between Cp infection and OAMZL. Available data on the epidemiology, biology and pathogenesis of this association are analyzed and new investigative and clinical approaches are discussed.

Low prevalence ofChlamydia psittaciin ocular adnexal lymphomas from Cuban patients

Most ocular adnexal lymphomas (OAL) are extranodal marginal zone B-cell lymphomas (EMZL) of mucosa-associated lymphoid tissue (MALT)-type. Chronic antigen stimulation has been suggested to have a pathogenetic role in EMZL and Chlamydia psittaci chronic infection has been recently associated with the development of OAL in a series of patients from Italy. To assess this association, an evaluation of the presence of C. psittaci was made in a different OAL population. DNA samples were obtained from formalin-fixed, paraffin-embedded sections samples of 26 patients with OAL, 20 non-OAL and 20 benign ocular lesions, diagnosed and treated between 1998 and 2003 at National Institute of Oncology in Havana, Cuba. All samples were histologically reviewed by an expert pathologist. Fluorescence in situ hybrization (FISH) analysis of translocations involving MALT1 was performed. The presence of bacterial DNA was assessed with a multiplex touchdown enzyme time release polymerase chain reaction. DNA sequencing was performed to confirm suspicious bands. Seventy-three percent of the OAL cases were EMZL and 81% were in stage IE. FISH analysis was performed in 13 OAL cases and none of them evidenced MALT1 translocations. DNA of C. psittaci was detected in 11% of the 46 lymphomas: two orbital EMZL and three non-OAL. All 20 benign ocular lesions were negative for C. psittaci. The low prevalence of C. psittaci in OAL suggests geographical differences in the etiology of this entity. International studies are needed to clarify the role of C. psittaci in OALs.