BACKGROUND: Chlamydia pneumoniae (Cpn) IgG and IgA has been strongly linked to lung cancer, but its impact on patients\' quality of life remains unclear. Our objective was to investigate the relationship between pre-treatment Cpn IgG and IgA and time to deterioration (TTD) of the HRQoL in patients with primary lung cancer.
METHODS: A prospective hospital-based study was conducted from June 2017 to December 2018, enrolling 82 patients with primary lung cancer admitted to the First Affiliated Hospital of Fujian Medical University for questionnaire surveys. Cpn IgG and IgA was detected by microimmunofluorescence method. HRQoL was assessed at baseline and during follow-up using the EORTC Quality of Life Questionnaire version 3.0 (EORTC QLQ-C30) and EORTC Quality of Life Questionnaire-Lung Cancer (EORTC QLQ-LC13). HRQoL scores were calculated using the QoLR package, and TTD events were determined (minimum clinically significant difference = 5 points). Cox regression analysis was used to evaluate the effect of Cpn IgG and IgA on HRQoL.
RESULTS: We investigated the relationship between Cpn IgG and IgA and quality of life in patients with primary lung cancer. The study was found that 75.61% of cases were Cpn IgG + and 45.12% were Cpn IgA + . Cpn IgA + IgG + was 41.46%. For EORTC QLQ-C30, Physical function (PF) and Pain (PA) TTD events on the functional scale and Symptom scale were the most common during follow-up. After adjusting for gender and smoking status, Pre-treatment Cpn IgA + was found to signifcantly delay TTD of Physical functioning(HR = 0.539, 95% CI: 0.291-0.996, P = 0.048). In addition, Cpn IgG + before treatment significantly delayed TTD in Emotional functioning (HR = 0.310, 95% CI: 0.115-0.836, P = 0.021). For EORTC QLQ-LC13, deterioration of dyspnea (LC-DY) was the most common event. However, Cpn IgG and IgA before treatment had no effect on the TTD of EORTC QLQ-LC13 items.
CONCLUSIONS: According to EORTC QLQ-C30 and EORTC QLQ-LC13, Cpn IgA delayed TTD in Physical functioning and Cpn IgG delayed TTD in Emotional functioning.

UNASSIGNED: Rosacea is a skin chronic inflammation with an unknown cause and cure. Environmental and genetic factors could not entirely explain the disease pathogenesis. Recently, infections like Chlamydia pneumoniae are of more attention in the rosacea progression. This study investigated the relationship between the C. pneumoniae seropositivity and the rosacea disorder.
UNASSIGNED: We aimed at a cohort of 100 patients with the rosacea disorder (60 active and 40 inactive) and from 100 sex- and age-matched healthy controls in Isfahan and determined the immunoglobulin M (IgM)/IgG antibodies titers to C. pneumoniae in the serum using the enzyme-linked immunosorbent assay method. The groups were compared using the analysis of variance procedure at the significant level of P < 0.05, statistically.
UNASSIGNED: The mean of IgG in the controls was significantly higher than the levels in both the active and the inactive rosacea patients (p < 0.022). Also, the titer of serum IgM to C. pneumoniae in the controls was different, compared with the active (p < 0.019) and the inactive (p < 0.02) rosacea patients. In addition, the median titer of serum IgG (not IgM) to C. pneumoniae in the females with the inactive rosacea disorder was lower than the active rosacea disorder (p < 0.019) and controls women (p < 0.008). Furthermore, the serum level of IgG or IgM to C. pneumoniae in the controls males was higher than the males with the rosacea disorder (p < 0.05) and (p < 0.02), alternatively.
UNASSIGNED: C. pneumoniae seropositivity in the rosacea patients and controls was insignificant.

Preeclampsia is one of the challenges associated with mother and baby health. Preeclampsia and atherosclerosis share certain similarities. Atherosclerosis has been previously linked to chronic Chlamydia pneumoniae infection. This investigation aimed to establish the role of chronic Chlamydia pneumoniae in the development and onset of preeclampsia. The research was conducted from October 1, 2018 to September 30, 2019 in the department of Obstetrics and Gynecology at Al-Yarmouk Teaching Hospital in Baghdad, Iraq. The study included 140 pregnant women divided into two groups: 70 women with early and late-onset preeclampsia and 70 women with late-onset preeclampsia. Group I (early-onset preeclampsia) included 35 singleton pregnant women who developed preeclampsia after 34 weeks with blood pressure>140/90 and proteinuria>1. Late-onset preeclampsia (group II) consisted of 35 singleton pregnant women who developed clinical preeclampsia after 34 weeks of pregnancy, with blood pressure>140/90 and proteinuria +1, and 70 healthy term pregnant women without complications who acted as the control group (Group III). Enzyme-Linked Immunosorbent Assay (ELISA) analyzers were utilized to measure serum Chlamydia pneumoniae IgG levels in all study groups. Women with early-onset preeclampsia had the highest median Chlamydia pneumonia IgG level, 0.3 U/ml, compared to 0.09 U/ml for women with late-onset preeclampsia and 0.19U/ml for healthy term pregnant women without complications; these differences were statistically significant (P=0.001). This study found that the IgG titer for Chlamydia pneumoniae was higher in early-onset preeclampsia than in late-onset preeclampsia and in healthy term pregnancy without complications. This substantial increase was a direct result of the onset of preeclampsia. This provided evidence for the pathophysiological connection between preeclampsia and the reactivation of a chronic or latent infection.

OBJECTIVE: To investigate the seroprevalence of the community-acquired bacterial that causes atypical pneumonia among confirmed severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) patients.
METHODS: In this cohort study, we retrospectively investigated the seroprevalence of Chlamydia pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila among randomly selected 189 confirmed COVID-19 patients at their time of hospital presentation via commercial immunoglobulin M (IgM) antibodies against these bacteria. We also carried out quantitative measurements of procalcitonin in patients\' serum.
RESULTS: The seropositivity for L. pneumophila was 12.6%, with significant distribution among patientsolder than 50 years (χ2 test, p=0.009), while those of M. pneumoniae was 6.3% and C. pneumoniae was 2.1%, indicating an overall co-infection rate of 21% among COVID-19 patients. No significant difference (χ2 test, p=0.628) in the distribution of bacterial co-infections existed between male and female patients. Procalcitonin positivity was confirmed amongst 5% of co-infected patients.
CONCLUSIONS: Our study documented the seroprevalence of community-acquired bacteria co-infection among COVID-19 patients. In this study, procalcitonin was an inconclusive biomarker for non-severe bacterial co-infections among COVID-19 patients. Consideration and proper detection of community-acquired bacterial co-infection may minimize misdiagnosis during the current pandemic and positively reflect disease management and prognosis.

UNASSIGNED: Stroke is considered as one of the most important concerns in health care centers around the world. By definition there are two types of stroke including ischemic stroke and hemorrhagic stroke. Approximately three-quarters of stroke cases are ischemic strokes, which occur due to several risk factors such as hypertension, obesity, atherosclerosis, diabetes mellitus, osteoarthritis, and inflammatory responses. In recent years, infectious diseases have noticed as a new risk factor for ischemic stroke. Given the importance of the issue, some bacteria that cause chronic infections, especially Chlamydia pneumonia, Helicobacter pylori, Mycoplasma pneumonia, Mycobacterium tuberculosis, and Coxiella burnetii have been considered.
UNASSIGNED: In the present meta-analysis, we reviewed 50 case-control studies and assessed the possible association of bacterial infections with the occurrence of ischemic stroke.
UNASSIGNED: We analyzed the information of 33,978 participants in several nested case-control studies, and ultimately showed that bacterial infections could increase the risk of ischemic stroke. Our results suggest that bacterial infections significantly increase in the risk of ischemic stroke (OR: 1.704; 1.57-1.84 with 95% CIs; p value = 0.01).
UNASSIGNED: In this meta-analysis, a significant relationship was observed between infection by three bacteria such as C. pneumoniae, H. pylori, and M. tuberculosis with the occurrence of ischemic stroke. Furthermore, due to the similarity between TLRVYK domain in β2-glycoprotein-I and TLRVYK peptide in various of microorganisms, produced antibodies against pathogens interact with β2-glycoprotein-I, hence the cross-reaction phenomenon increases the positive relationship between infectious diseases and ischemic stroke.

BACKGROUND: Chlamydia pneumoniae is a common cause of atypical community acquired pneumonia (CAP). The diagnostic approach of chlamydial infections remains a challenge. Diagnosis of delayed chlamydial-associated complications, involving complex autoimmune pathophysiological mechanisms, is still more challenging. C. pneumoniae-related cardiac complications have been rarely reported, including cases of endocarditis, myocarditis and pericarditis.
METHODS: A 40-year old female was hospitalized for pleuropericarditis following lower respiratory tract infection. The patient had been hospitalized for CAP (fever, dyspnea, chest X-ray positive for consolidation on the left upper lobe) 5 weeks ago and had received ceftriaxone and moxifloxacin. Four weeks after her discharge, the patient presented with fever, shortness of breath and pleuritic chest pain and was readmitted because of pericardial and bilateral pleural effusions (mainly left). The patient did not improve on antibiotics and sequential introduction of colchicine and methylprednisolone was performed. The patient presented impressive clinical and laboratory response. Several laboratory and clinical assessments failed to demonstrate any etiological factor for serositis. Chlamydial IgM and IgG antibodies were positive and serial measurements showed increasing kinetics for IgG. Gold standard polymerase chain reaction of respiratory tract samples was not feasible but possibly would not have provided any additional information since CAP occurred 5 weeks ago. The patient was discharged under colchicine and tapered methylprednisolone course. During regular clinic visits, she remained in good clinical condition without pericardial and pleural effusions relapse.
CONCLUSIONS: C. pneumoniae should be considered as possible pathogen in case of pleuritis and/or pericarditis during or after a lower respiratory tract infection. In a systematic review of the literature only five cases of C. pneumoniae associated pericarditis were identified. Exact mechanisms of cardiovascular damage have not yet been defined, yet autoimmune pathways might be implicated.

Respiratory pathogens such as Chlamydia pneumoniae may activate osteoclast cells, thereby inducing bone resorption and joint inflammation. Herein is a case report of a young man with misdiagnosed persistent wrist pain without any major trauma. Investigation of the patient\'s medical history confirmed a recent systemic C. pneumoniae infection. Preoperative X-ray and magnetic resonance imaging (MRI) showed a substantial decrease in cancellous lunate bone compactness. A stepwise approach was undertaken considering the rapid onset of bone devascularisation and the clinical presentation. Wrist arthroscopy confirmed extensive joint inflammation associated with decreased osteochondral lunate solidity. Microbiological examination excluded joint infection. Histological analysis showed a diffuse inflammatory infiltration. Temporary mediocarpal K-wire stabilization and synovectomy were performed. Postoperative MRI confirmed lunate bone revascularization. At 6 and 12 months\' follow-up the young man was pain-free and had good recovery of range of motion. In vitro and in vivo studies demonstrate that inflammatory conditions may promote osteoclast cell activity and induce bone resorption. Moreover, infection with C. pneumoniae could activate specific \"osteoporotic\" bone pathways. To the authors\' knowledge, this is the first published case report of specific lunate bone loss induced by systemic C. pneumoniae infection. The authors proposed an etiologic explanation, and a stepwise approach was associated with good outcome.

OBJECTIVE: To provide some epidemiological data on Chlamydia pneumoniae infection rates in paediatric patients at a single centre in Wuxi, China.
METHODS: This was a retrospective analysis of serum samples from paediatric patients (<12 years) with a respiratory tract infection (RTI) and who had been admitted to the Department of Paediatrics, Wuxi No.2 People\'s Hospital, China, from 01 January 2015 to 31 December 2016. C. pneumoniae IgM antibodies had been analysed using enzyme-linked immunosorbent assay (ELISA).
RESULTS: Of the 3866 children (2073 boys, 1793 girls) with a RTI that provided serum samples, 19% were positive for C. pneumoniae IgM antibodies. Among these children, 56% were positive for other infections.
CONCLUSIONS: Children over 6 years of age with a RTI had a higher C.pneumoniae infection rate than younger children and the infection rate was more common in winter months compared with other times of the year.

Aim: To explore the relationship between Chlamydia pneumonia (Cpn) infection and lung cancer using integrative methylome and transcriptome analyses. Methods: Twelve primary lung cancer patients who were positive for Cpn and twelve patients who were negative were selected for demographic, clinicopathological, and lifestyle matching. Genomic DNA and RNA were extracted and DNA methylation and mRNA levels were detected using the Infinium Human Methylation 450 Beadchip array and mRNA + lncRNA Human Gene Expression Microarray. We identified differentially expressed methylation and genes profiles. Results: Integrative analysis revealed an inverse correlation between differentially expressed genes and DNA methylation. Cpn-related lung cancer methylated genes (target genes) were introduced into the gene ontology and KEGG, PID, BioCarta, Reactome, BioCyc and PANTHER enrichment analyses using a q-value cutoff of 0.05 to identify potentially functional methylation of abnormal genes associated with Cpn infection. Gene sets enrichment analysis was evaluated according to MsigDB. Levels of differentially expressed methylated sites were quantitatively verified. The promoter methylation sites of 62 genes were inversely related to expression levels. According to the quantitative analysis of DNA methylation, the methylation level of the RIPK3 promoter region was significantly different between Cpn-positive cancerous and adjacent tissues, but not between Cpn-negative cancerous and adjacent tissues. Conclusion:  Hypomethylation of the RIPK3 promoter region increases RIPK3 expression, leading to regulated programmed necrosis and activation of NF-κB transcription factors, which may contribute to the development and progression of Cpn-related lung cancer.

BACKGROUND: Hajj pilgrimage is the biggest and longest mass gathering in the Muslim world. Annually, about 50% of more than 2.5 million pilgrims participating in this ritual get involved in severe devastating coughs. Most coughs continue, so the pilgrims turn back home and transmit them to family members and other people. Despite the high prevalence of coughs for many years, what causes them remains unknown. Considering the pertussis-like clinical picture of the so-called \"hajj coughs\", the researchers conducted a study to measure antibodies against three known common atypical bacteria, namely Bordetella Pertussis, Chlamydia Pneumonia and Mycoplasma Pneumonia.
METHODS: The study was done on three out of eleven groups of pilgrims from Yazd province, central Iran. The sample was selected randomly and consisted of 202 pilgrims who completed an informed consent. Their blood samples were taken, and the plasma was separated and then stored at -70 °C. After turning back from the journey, the pilgrims had their second blood samples taken. As many as 52 pilgrims failed to come for the second sampling, and two samples were broken during transportation. The final analysis was performed on the remaining 148 pairs of samples.
RESULTS: Antibodies were already elevated in many pilgrims before the journey probably due to their old age (causing more exposure to pathogens) or unplanned pertussis vaccination. After their return, antibody elevation was only mild, again probably due to the old age of the participants (i.e. due to their weaker immune systems). Some antibodies even fell down without any known reason. In this study, previous hajj journey was assumed as a prophylactic factor, due to acquisition of immunity. Coughs with a prolonged pertussis-like picture were also presumed to be more related than other types of coughs to atypical pathogens. Statistical tests showed that the history of previous journeys had no prophylactic effect. Also, no correlation was found between the clinical pictures of coughs and infection with atypical bacteria.
CONCLUSIONS: Even though some rises and falls occurred in the antibodies titer, the variations could hardly be attributed to coughs in this study. Indeed, the variation of antibodies had no meaningful relationship with clinical factors. In this regard, further studies are needed to clarify the reason for the so-called \"hajj coughs\", but epidemiological studies will be difficult to do until easier and more reliable methods become available for accurate diagnosis.