Pseudomembranous Colitis: Insights into Causes, Diagnostic Methods, and Treatment Approaches

Pseudomembranous colitis (PMC) is a severe inflammatory condition of the colon most commonly associated with Clostridioides difficile infection (CDI), typically occurring after disruption of normal gut microbiota due to antibiotic exposure. The condition is characterized by profuse watery diarrhea, abdominal pain, fever, and marked leukocytosis, with severe cases progressing to toxic megacolon, sepsis, or death. Although CDI accounts for the majority of cases, pseudomembranous colitis may also arise from non-clostridial infectious agents, inflammatory bowel disease, ischemia, and drug-induced mucosal injury. Diagnosis relies on a combination of clinical assessment and laboratory testing, including glutamate dehydrogenase antigen detection, toxin A/B assays, and nucleic acid amplification tests, with endoscopic evaluation reserved for selected cases. Current treatment strategies emphasize oral vancomycin or fidaxomicin as first-line therapy, while metronidazole is reserved for limited situations. Recurrent and severe disease remains a significant clinical challenge, particularly with the emergence of hypervirulent strains such as NAP1/027. Preventive strategies focusing on antibiotic stewardship and early recognition are essential to reduce disease burden. This review provides an updated overview of the etiological factors, diagnostic modalities, and evidence-based management approaches for pseudomembranous colitis, highlighting recent advances and ongoing challenges in clinical practice.