Search Results (480)

Sexually transmitted infections (STIs) are common and probably underreported causes of proctitis and colitis. Bacterial (chlamydia, gonorrhoea, syphilis, Mycoplasma genitalium), viral (herpes simplex virus, mpox), and amoebic (Entamoeba histolytica) pathogens can cause inflammatory proctitis or colitis, which, depending on the pathogen, can mimic inflammatory bowel disease both on endoscopy and histopathology. Rectal and colonic masses are uncommon, but important manifestations of these infections, especially with chlamydia, syphilis, and E. histolytica. Testing for HIV is important in this context, since it allows for the inclusion of opportunistic pathogens into the differential diagnosis. Chronic diarrhoea can be a feature of chronic HIV infection. Enteric pathogens, such as Salmonella spp., Shigella spp., or Campylobacter spp., can be transmitted during sex, especially during oral–anal contact (“rimming”). The most common STI, human papillomavirus, is not associated with colitis, but is important because of its causal association with genital warts and anal cancer. Full article

Tick-borne pathogens remain insufficiently investigated in donkeys, particularly in southeastern Europe. This study investigated the occurrence of piroplasms, Anaplasmataceae, and hemotropic Mycoplasma spp. in donkeys from Croatia and assessed the genetic diversity of detected Theileria equi. Blood samples from 135 apparently healthy donkeys originating from 15 herds in six Croatian counties were examined using PCR. Positive T. equi samples were further characterized by sequencing, haplotype determination, and phylogenetic analysis. Theileria equi DNA was detected in 31/135 animals (22.96%; 95% CI: 15.99–29.94%), whereas no Anaplasmataceae or hemotropic Mycoplasma spp. DNA was detected. Infection showed marked geographical and herd-level variation. The highest prevalence was recorded in Šibensko-Kninska County (17/34; 50.0%), while all positive animals originated from three herds in the Croatian littoral region. Prevalence differed significantly among herd-size categories (p = 0.012), with no positive animals detected in small herds. Sequence analysis identified three T. equi haplotypes: D was predominant (22/31; 70.97%), followed by A (8/31; 25.81%) and E (1/31; 3.23%). Phylogenetic analysis confirmed all Croatian sequences as T. equi and indicated the presence of multiple genetic lineages within the sampled donkey population. These findings provide new molecular epidemiological data on T. equi in Croatian donkeys and demonstrate a heterogeneous distribution of infection among the investigated regions and herds. Among the selected tick-borne pathogens investigated, T. equi was the only pathogen detected. Further studies integrating larger and longitudinal datasets with detailed management, environmental, and tick-vector data are needed to better understand the factors underlying the observed epidemiological patterns. Full article

The rising prevalence of macrolide and fluoroquinolone resistance in human pathogenic mycoplasmas, such as Mycoplasma pneumoniae and Mycoplasma genitalium, threatens global public health. Mutations in 23S rRNA and quinolone resistance-determining regions (QRDR) have compromised the first-line therapies, creating an urgent clinical need for alternatives. Consequently, novel antimicrobial agents (pleuromutilins, novel tetracyclines, topoisomerase inhibitors) have become a top research priority. However, standardized in vitro pharmacokinetic/pharmacodynamic (PK/PD) methodologies for mycoplasmas remain underdeveloped compared to typical bacteria. Key challenges include the lack of a cell wall, slow growth kinetics, and fastidious culture requirements, which invalidate standard colony-counting and susceptibility testing protocols. This review evaluates current in vitro PK/PD models, quantification techniques, and key indices, highlighting the potential of adapting the methodological frameworks established in veterinary mycoplasma research (e.g., Mycoplasma bovis, Mycoplasma hyopneumoniae) to human mycoplasma species. We specifically analyze the utility of propidium monoazide (PMA)-qPCR for viability assessment and hollow-fiber infection models (HFIM) configured for small-cell retention. We conclude that harmonizing these methodologies through a One Health approach is critical for optimizing dosing regimens, reducing resistance, and accelerating the development of novel antimicrobial agents for human use. Full article

Early, rapid, and accurate detection is essential for clinical management and epidemiological control of acute respiratory infections caused by pathogens. Traditional testing methods such as microbial culture, serological testing, and PCR are restrictive in terms of operation and logistics and are therefore not easily used in point-of-care settings. The CRISPR/Cas system is an adaptive prokaryotic immune system composed of clustered regularly interspaced short palindromic repeats and their associated proteins, which has been used as a nucleic acid diagnostic platform with programmable sequence-specific target recognition and signal-amplifying collateral cleavage activity. Existing reviews have mostly focused on the classification of Cas enzymes or amplification strategies; in this review, a pathogen-centric approach was taken, covering viral pathogens (SARS-CoV-2, influenza virus, RSV, HAdV and VZV), bacterial pathogens (Mycobacterium tuberculosis, Streptococcus pneumoniae, Mycoplasma pneumoniae and Staphylococcus aureus) and fungal pathogens (Aspergillus fumigatus and Pneumocystis jirovecii). Key technological advances, such as isothermal amplification coupling, single-vessel integrated reaction designs, amplification-free digital detection, and electrochemical biosensor integration, are evaluated for Cas9-, Cas12-, and Cas13-based systems, with their mechanistic bases outlined. The current challenges that hinder clinical translation, such as sample matrix interference, multiple signal cross-talk, crRNA off-target effects, and the lack of large-scale validation studies, are critically assessed. At the same time, future pathways for portable, integrated, and inexpensive diagnostic platforms are suggested. Full article

Background: Community-acquired pneumonia (CAP) remains a leading cause of pediatric morbidity and mortality worldwide, particularly in low-resource settings. Although antimicrobial therapy is the cornerstone of treatment, disease severity is often influenced not only by pathogen burden but also by dysregulated host inflammation. Systemic corticosteroids have therefore been investigated as adjunctive agents to reduce inflammation-mediated lung injury, but their role in children remains controversial. Methods: This narrative review summarizes current evidence on systemic corticosteroid use in pediatric pneumonia. The review focuses on biological mechanisms, clinical indications, patient selection, therapeutic regimens, timing and duration of therapy, clinical outcomes, and safety. Particular attention is given to severe CAP, Mycoplasma pneumoniae pneumonia, complicated pneumonia with parapneumonic effusion or empyema, viral pneumonia, wheezing-associated phenotypes, and immunocompromised children. Results: Available evidence suggests that corticosteroids may provide benefit in selected pediatric phenotypes characterized by severe inflammation, respiratory compromise, refractory disease, or airway hyperreactivity. Reported benefits include faster fever resolution, reduction in inflammatory markers, shorter hospital stay, more rapid clinical stabilization, and improved radiographic recovery, particularly in severe or refractory Mycoplasma pneumoniae pneumonia and selected complicated cases. However, findings are inconsistent, and treatment effects appear strongly dependent on etiology, disease severity, timing of administration, corticosteroid regimen, and patient phenotype. Routine use in uncomplicated CAP or unselected pediatric populations is not supported. Potential adverse effects include hyperglycemia, gastrointestinal and neurobehavioral symptoms, sleep disturbance, immunosuppression with an increased risk of secondary infection, delayed viral clearance in selected viral infections, and possible masking of inadequate anti-infective response or evolving complications. Conclusions: Current evidence supports a cautious, individualized, phenotype-driven approach to corticosteroid therapy in pediatric CAP. Well-designed pediatric randomized controlled trials are needed to define precise indications, optimal regimens, timing, and long-term safety. Full article

Mycoplasma bovis (M. bovis) is a major pathogen in cattle, primarily responsible for bovine respiratory disease complex (BRDC). Characterized by high infectivity and morbidity, M. bovis spreads rapidly within herds and is challenging to control and eradicate, underscoring the need for early and accurate diagnosis. To address this, we developed a competitive enzyme-linked immunosorbent assay (cELISA) for detecting M. bovis-specific antibodies in bovine sera. The assay uses recombinant MbovP579 protein (1 μg/mL) as the coating antigen and an HRP-conjugated 1A2 monoclonal antibody against MbovP579 (mAb, 0.35 μg/mL) as the competitor. With a cut-off value of 40.69% (percentage inhibition, PI), the cELISA demonstrated apparent sensitivity (90%; 95% CI: 78.64–95.65%) and specificity (96.15%; 95% CI: 90.53–98.49%) using the known background positive and negative sera. In addition, it yielded 100% positivity (9/9) against sera collected from 21 days post-immunization. The assay showed no cross-reactivity with other Mycoplasma species or two common bovine bacterial pathogens, confirming its high specificity. The intra- and inter-assay coefficients of variation (CVs) were below 10%. In clinical evaluations, this cELISA generated a 55.57% positivity rate for field samples (n = 1069) and exhibited 90.46% overall agreement (967/1069; 95% CI: 88.54–92.15%) with the commercial indirect ELISA kit, demonstrating strong diagnostic consistency. Discrepant specimens were further analyzed by a metabolic inhibition test (MIT), which suggested improved specificity, although further validation is required of this cELISA. Full article

Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are regarded as the most clinically and economically important avian Mycoplasma species, posing significant challenges to the poultry industry worldwide. In this study, MG and MS antibodies were detected by ELISA in 857 unvaccinated Chinese native chickens from 21 breeder flocks on four multi-age farms. The overall seropositive rates were 86.3% for MG and 98.4% for MS. Offspring from an infected breeder flock were reared under different environmental conditions, and serological monitoring was conducted over a 68-week production cycle. The antibody titers and seropositive rates of both mycoplasmas in birds reared in an isolation room were significantly lower than those in birds reared on the farm after maternal antibodies vanished. By adopting strict biosecurity measures, MG and MS infections were effectively controlled in an offspring flock derived from infected breeders, as evidenced by a substantial decrease in seropositive rates. The results suggested that MG and MS infections were prevalent in the breeder flocks of Chinese native chickens. Horizontal rather than vertical infection was the primary cause of high flock infection levels under field conditions. Strict biosecurity measures could be adopted to initially control MG and MS infections in offspring from the breeder flocks with high infection levels. Full article

Extraintestinal pathogenic Escherichia coli (ExPEC) are opportunistic pathogens in pigs and can cause systemic infections with neurological signs. Cases in suckling piglets have rarely been reported. In November 2024, suckling piglets aged 1–3 weeks on a commercial pig farm developed neurological signs, including altered consciousness, vertical nystagmus, ataxic gait, and recumbency. Within two affected batches comprising 1150 and 1200 piglets, 17 and 26 animals, respectively, developed clinical signs (morbidity 1.48% and 2.17%). Initial treatment with amoxicillin and dexamethasone was ineffective. Early administration of intramuscular enrofloxacin combined with dexamethasone was associated with clinical improvement in approximately 50% of affected piglets. Pathological examination revealed atelectatic lung regions, dilated small intestines with yellowish content, and moderate mesenteric vessel congestion. Histologically, the central nervous system of both piglets exhibited hyperemia, edema, disseminated diapedesis hemorrhages, thrombi, and intravascular rod-shaped bacteria. E. coli was isolated from the CNS, lungs, pericardium, and joints. Molecular analysis confirmed the presence of virulence-associated genes fimA, fimH, and iucD. Differential diagnostic PCRs for Streptococcus suis, Glaesserella parasuis, and Mycoplasma hyorhinis were negative. This case report documents the first occurrence of an ExPEC-like E. coli infection in this herd. The documented clinical, pathological, and molecular findings support the importance of considering ExPEC-like E. coli as a differential diagnosis in therapy-resistant neurological diseases in piglets. Full article

Bovine Mycoplasma bovis pneumonia (MBP) is an important component of bovine respiratory disease, and its management is complicated by persistent infection and antimicrobial stewardship concerns. Houttuynia cordata Thunb. has reported anti-inflammatory and immunomodulatory activities, but its potential host-directed mechanisms in MBP remain unclear. This in silico study used network pharmacology and molecular docking to identify candidate compounds, common drug–disease targets, enriched biological functions, and predicted ligand–target interactions. A total of 145 putative targets of H. cordata and 474 MBP-associated disease targets were obtained from TCMSP, GeneCards, OMIM, and CTD, yielding 43 common drug–disease targets. Dual-confidence STRING analysis, cytoHubba ranking, and MCODE module analysis prioritized TNF, IL6, IL1B, PTGS2, PPARG, IFNG, CASP3, and MMP9 as candidate core targets. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated convergence on cytokine-mediated signaling, inflammatory response, immune regulation, oxidative stress, IL-17 signaling, and TNF signaling. Molecular docking suggested favorable predicted interactions for quercitrin–PTGS2, quercetin–TNF, quercetin–IL6, and quercitrin–CASP3. These computational findings suggest that H. cordata may be associated with host inflammatory and immune-response modulation in MBP, mainly through flavonoid-related interactions with inflammation- and apoptosis-related targets. Further bovine-specific experimental validation is required before biological activity or practical application can be inferred. Full article

Background/Objectives: Pediatric acute-onset neuropsychiatric syndrome (PANS) describes the rapid onset of obsessive–compulsive symptoms or severe food restriction, accompanied by neuropsychiatric or somatic features that are not better explained by another disorder. PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections) is a related, more narrowly defined construct in which symptoms are temporally associated with group A Streptococcus infection. This review examines clinical symptoms, infectious associations, proposed immune mechanisms, biomarker limitations, and treatment strategies for infection-associated PANS/PANDAS. Methods: A structured narrative search of PubMed/MEDLINE, Embase, the Cochrane Library, Google Scholar/publisher-indexed literature, ClinicalTrials.gov, and reference lists was performed up to 16 June 2026. Original cohorts, case series, systematic reviews, narrative reviews, consensus guidance, mechanistic studies, and registered prospective studies were prioritized. The review was not designed as a PRISMA-ScR scoping review; however, the methods were expanded to improve transparency and align with SANRA principles. Results: Group A Streptococcus remains the best characterized infectious association, although prospective studies have not uniformly demonstrated a consistent temporal relationship between streptococcal infection and neuropsychiatric exacerbations. Parent-reported surveys and case-based literature also describe temporal associations with Mycoplasma pneumoniae, influenza-like illnesses, upper respiratory infections, Borrelia burgdorferi, Epstein–Barr virus, and SARS-CoV-2. Proposed mechanisms include molecular mimicry, anti-D1R and anti-D2R antibodies, other antineuronal antibodies, calcium/calmodulin-dependent protein kinase II signaling, blood–brain barrier vulnerability, cytokine and Th17 effects, neuroinflammatory amplification, basal ganglia/CSTC circuit dysfunction, and gut–oral–brain immune interactions. None currently provides a definitive diagnostic biomarker. Conclusions: Infection-associated PANS is best approached as a clinically defined, heterogeneous neuroimmune presentation that requires rigorous differential diagnosis, multidisciplinary care, cautious treatment escalation, prospective biomarker validation, and large, multicenter treatment trials. Full article

Sexually transmitted infections remain a major public health concern among men who have sex with men (MSM), particularly due to the high frequency of coinfections and the limitations of syndromic management. This study aimed to describe the frequency of bacterial sexually transmitted and urogenital pathogens among symptomatic MSM attending two specialized sexual health clinics in Mexico City. A prospective cross-sectional study was conducted with 150 adult MSM presenting symptoms suggestive of urethritis. Urethral swab samples were analyzed using a multiplex real-time polymerase chain reaction (PCR) assay for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, Ureaplasma parvum, and Trichomonas vaginalis. At least one pathogen was detected in 91/150 participants (60.7%). N. gonorrhoeae was the most frequent pathogen (33.3%), followed by U. urealyticum (15.3%), M. genitalium (9.3%), and C. trachomatis (9.3%). Coinfections were identified in 15 participants, representing 10.0% of the total population and 16.5% of those with a positive PCR result. Most coinfections involved N. gonorrhoeae, particularly with C. trachomatis. These findings provide descriptive microbiological evidence on the frequency and coinfection patterns of bacterial sexually transmitted infections (STIs) associated pathogens among symptomatic MSM attending specialized sexual health clinics in Mexico City. The high detection rate and occurrence of concurrent infections highlight the limitations of syndromic management and support the value of timely multiplex molecular diagnostics to improve etiological characterization, antimicrobial stewardship, and clinical decision-making in this population. Full article

Objectives: To assess the prevalence of high-risk human papillomavirus (hrHPV) infection and selected genitourinary pathogens and to examine their co-detection patterns in sexually active adolescent females. Methods: In this single-center cross-sectional study, 167 consecutive outpatients aged 13–17 years with self-reported sexual initiation underwent multi-pathogen polymerase chain reaction (PCR) testing for hrHPV, Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU), Ureaplasma parvum (UP), and Mycoplasma genitalium (MG). Prevalence estimates are reported with 95% confidence intervals (CIs). Associations with hrHPV positivity were explored using univariable and parsimonious multivariable logistic regression; sensitivity analyses examined alternative age parameterization and exclusion of sparse variables. Results: The prevalence of hrHPV was 28.1% (47/167; 95% CI: 21.5–35.6). The prevalence of CT, UU, UP, and MG was 3.0%, 28.1%, 25.1%, and 0.6%, respectively. Any bacterial pathogen was detected in 61/167 participants (36.5%), while hrHPV–bacterial co-detection was observed in 24/167 (14.4%). In univariable analysis, UU was associated with hrHPV positivity (OR 2.55, 95% CI: 1.24–5.24; p = 0.013); this signal remained in the primary multivariable model (adjusted OR 2.46, 95% CI: 1.07–5.93; p = 0.035). A graded increase in hrHPV positivity was observed with increasing bacterial burden (p for trend = 0.018). Conclusions: Sexually active adolescent girls attending gynecologic outpatient care showed a substantial burden of hrHPV and bacterial genitourinary pathogen detection. This Central and Eastern European adolescent outpatient cohort contributes integrated multi-pathogen PCR-based epidemiologic data from a clinically relevant and underreported population. An exploratory association between UU and hrHPV positivity was observed; this signal is best interpreted as reflecting shared sexual exposure or the cervicovaginal microbial milieu rather than as evidence of an independent causal role for UU. The absence of vaccination status, behavioral, and longitudinal data represents a principal limitation. Prospective studies incorporating these variables are needed to clarify the epidemiology of hrHPV and co-detected pathogens in adolescents. Full article

Canine vector-borne pathogens (CVBPs) pose a major challenge in shelter medicine, yet data from shelter populations in Vietnam remain unknown. This study determined the prevalence, and risk factors of CVBPs in shelter dogs in northern Vietnam. Blood samples from 300 apparently healthy dogs from three shelters in Hanoi were screened by PCR for Babesia vogeli, Hepatozoon canis, Rickettsia spp., and Mycoplasma spp. Representative positive amplicons underwent Sanger sequencing and BLAST analysis. Sequence analysis showed 96.07–100% identity with reference strains, with phylogenetic trees confirming clustering within B. vogeli, H. canis, M. haemocanis and R. felis clades. Overall, 43.7% (131/300) of dogs were infected with at least one pathogen, with shelter-level prevalence ranging from 38.0 to 52.0%. Single infections accounted for 35.0%, dominated by R. felis (25.7%) and M. haemocanis (24.0%), B. vogeli and H. canis were low (1.3% each). Co-infections were found in 8.7% of dogs, primarily R. felis and M. haemocanis (8.3%). No evaluated host factors (age, sex, breed, body size, housing style) significantly associated with infection (p > 0.05). This study provides the first molecular evidence of canine vector-borne pathogen circulation in Vietnamese shelter dogs, emphasizing the need of ectoparasite control and One Health-oriented surveillance. Full article

Vector-borne pathogens (VBPs) can affect equine health, welfare, and productivity, with potential implications for animal management and trade. However, data on their occurrence in North Africa remain limited. The present study aimed to estimate the molecular occurrence of selected equine VBPs in clinically healthy horses from Algeria. Specifically, a cross-sectional molecular survey was conducted between May and November 2024 on 241 clinically healthy horses selected using convenience sampling from three ecologically distinct regions of Algeria (Tiaret, Laghouat, and Tlemcen). Demographic and management data were collected at sampling, and blood samples were spotted onto filter paper for DNA preservation. Genomic DNA was extracted using a modified Chelex/InstaGene Matrix protocol, followed by conventional and nested PCR assays targeting piroplasms, Anaplasmataceae, filarioid helminths, Rickettsia spp., Trypanosomatidae, haemotropic Mycoplasma spp., and Bartonella spp. Positive amplicons were subjected to sequence and phylogenetic analysis. Theileria equi (T. equi) DNA was detected in 4.98% (12/241) of examined horses, and one animal (0.41%; 1/241) tested positive for Theileria capreoli (T. capreoli). T. equi genotypes A and B were identified via molecular characterisation, but no amplification was obtained for Anaplasmataceae, Babesia caballi, Rickettsia spp., haemotropic Mycoplasma spp., Bartonella spp., Trypanosomatidae, or filarioid helminths. These findings should be interpreted cautiously, given the convenience sampling design, the clinically healthy status of the sampled animals, and the known limitations of PCR-based detection in low-parasitaemia infections. Nevertheless, this study provides preliminary molecular data on equine VBPs in Algeria and supports the need for broader epidemiological investigations using complementary molecular and serological approaches. Full article

Ovine Respiratory Complex is a multifactorial disease involving interactions between pathogens, host factors, and environmental conditions. This study investigated associations between selected bacterial agents, including Mycoplasma ovipneumoniae infection and members of the Pasteurellaceae family, and clinical, auscultatory, ultrasonographic, and post-mortem findings in Lacaune fattening lambs. A total of 80 animals were evaluated using clinical examination, thoracic auscultation, ultrasonography, post-mortem assessment, bacteriological culture, and quantitative PCR (qPCR) for Mycoplasma ovipneumoniae. Associations between microbial detection and disease severity scores were analyzed. Mycoplasma ovipneumoniae was the most frequently detected organism (50%), followed by Pasteurella multocida (32.9%) and Trueperella pyogenes (27.8%). Detection of specific microorganisms was more frequently observed in animals with increased disease severity across multiple diagnostic modalities. Coinfection was identified in 60.8% of animals and was significantly associated with increased severity according to clinical, auscultatory, ultrasonographic, and post-mortem scores. These findings underscore the polymicrobial nature of ORC and emphasise the necessity of employing complementary diagnostic approaches for disease evaluation. Full article