مقالات پذیرفته شده در نهمین کنگره بین المللی زیست پزشکی
Challenges and Advances in the Diagnosis and Management of Clostridioides difficile and Klebsiella pneumoniae Infections and colonization: A Narrative Review
Challenges and Advances in the Diagnosis and Management of Clostridioides difficile and Klebsiella pneumoniae Infections and colonization: A Narrative Review
Yasaman Latifi,1,*Atena Mohammadzadeh,2
1. Islamic Azad University of Medical Sciences 2. Islamic Azad University of Medical Sciences
Introduction: Public health faces a global threat posed by Clostridioides difficile (CDI) and Klebsiella pneumoniae (Kp) infections, picked up at hospitals. We currently face the medical dilemma of differentiating between asymptomatic colonization and invasive infection, the said process being influenced by host factors, microbial ecology, and bacterial genomics. This narrative review integrates clinical, microbiome, and genomic information, with an emphasis on new diagnostic platforms and predictive tutorials to close the gap between colonization and infection.
Methods: This study is a narrative review of the literature on CDI and Kp infections. Published studies, including clinical reports, microbiome analyses, genomic investigations, and emerging diagnostic technologies, were reviewed. Emphasis was placed on integrating information from clinical, laboratory, microbiome, and genomic perspectives. Databases including Google Scholar, PubMed Central (PMC), Directory of Open Access Journals (DOAJ) and ResearchGate were used to identify relevant articles, focusing on publications that discuss atypical presentations, diagnostic challenges, and predictive strategies
Results: Speaking of CDI, we face a major challenge in the diagnosis of atypical cases, especially the ones without diarrhea. Routine laboratory protocols often choose to exclude these cases from testing, which results in delayed recognition, higher mortality, and increased need for surgical intervention. Using non-specific markers such as fever and leukocytosis tends to result in the failure of timely diagnosis. At the same time, imaging and colonoscopy, even though useful, fail to achieve expected specificity. Diagnostic schemes involving multiple steps in which glutamate dehydrogenase (GDH) screening is combined with enzyme immunoassays (EIA) or nucleic acid amplification tests (NAATs) improve diagnostic performance, but the use of NAATs stands the risk of overdiagnosing colonized patients. Emerging technologies like CRISPR-Cas12a in combination with recombinase polymerase amplification, highly sensitive immunodiagnostics like Single Molecular Array (SIMOA), and NanoBiT luciferase assays allow fast, portable, and accurate detection of toxins. Machine learning-assisted MALDI-TOF-MS also enables ribotype discrimination that is relevant to epidemiological monitoring. Thus, the above evidence shows the necessity for protocols that recognize nondiarrheal patients and integrate multi-modal diagnostic strategies. Likewise, Kp also demonstrates the range from colonization to infection, specifically when multidrug-resistant (MDR), carbapenem-resistant (CRKp), and hypervirulent (hvKp) strains are being studied. Up to 77% of hospitalized patients carry Kp in the gut, with possible infections growing endogenously. Older age, hypoalbuminemia, ICU admission, and carriage of resistant traits are identified as risk factors by clinical prediction models, with machine learning (such as Random Forests) achieving high predictive precision. Microbiome analysis shows that gut community, including the population of Kp and reduction in commensal members like Akkermansia, influences infection risk. Genomic data shows the role of capsule groups, siderophores, and plasmid-borne carbapenemases, with epidemic strains ST11 and ST258 dominant in Asian ICUs. Importantly, lineages carrying both resistance and virulence plasmids show the convergence of two threats with outbreak potential. With prevention strategies—routine colonization screening, infection control, and antimicrobial stewardship—on the foundation, bacteriophage therapy and capsule-based vaccines are being studied. For both pathogens, the same issue stands: the insufficiency of single-domain approaches. For CDI, trusting diarrhea as a precondition for a test underestimates fulminant cases. For Kp, not taking colonization dynamics into account downplays the infection threat. Together, multi-step laboratory protocols, new molecular diagnostics, microbiome profiling, and genomic analysis with predictive models offer an improved guide for early treatment and detection. But putting the said technique to work is limited by small cohort sizes, absent real-time microbiome surveillance, and the challenge of the trade-off between sensitivity and medical interpretability
Conclusion: CDI and Kp showcase the complicated relation between colonization, infection, and clinical outcome. Developments in immunoassays, machine learning, and molecular diagnostics promise potential, but they must be used within systemic algorithms regulated for atypical presentations, microbial ecology, and host susceptibility. This review claims that there is a need for integrated conceptual frameworks to connect clinical, laboratory, and genomic paradigms in an effort to improve early diagnosis, reduce unnecessary antibiotic use, and face the worldwide healthcare issue of nosocomial CDI and Kp infections.