The development of PMC is strongly linked to the disruption of normal intestinal flora, which most often occurs after broad-spectrum antibiotic therapy. Clindamycin, cephalosporins, fluoroquinolones, and penicillins are frequently linked to C. difficile because they can kill the good bacteria in the stomach, providing an environment conducive to its growth. This bacteria produces two main toxins: toxin A (an enterotoxin) and toxin B (a cytotoxin), which damage the colonic lining, causing cell death, inflammation and the creation of pseudomembranes. PMC is most often encountered in hospitalized or elderly people, particularly when receiving long or numerous doses of antibiotics. Other risk factors include immunosuppression, use of proton pump inhibitors (PPIs), and underlying gastrointestinal disorders.

Clinical manifestations of PMC range from mild diarrhea to severe colitis with systemic signs. Patients usually experience profuse watery diarrhea, which may be accompanied by stomach upset, cramping, and pain. Other symptoms include fever, nausea and malaise. In extreme situations, patients can suffer from dehydration, electrolyte imbalance, hypoalbuminemia and considerable weight loss. PMC should be suspected in people who develop new diarrhea while taking antibiotics or shortly after they finish. The disorder is also linked to an increase in the number of white blood cells (leukocytosis) and an increase in inflammatory markers. In its most severe forms, PMC can cause toxic megacolon, colon perforation, and sepsis, all of which can be fatal if not treated promptly. PMC is diagnosed using a variety of clinical presentations, laboratory tests, and imaging. A stool test for C. difficile toxins, or nucleic acid amplification tests (NAATs), is commonly used to confirm the presence of the bacteria and its toxins. Endoscopy can reveal the distinctive pseudomembranes, although it is often reserved for situations where the diagnosis is uncertain or there is suspicion of serious disease.

The main goal of PMC treatment is to stop the offending drug if possible, then follow up with the use of specific antibiotics effective against C. difficile, such as oral vancomycin or fidaxomicin. Metronidazole can be used in milder situations, although it is ineffective against serious infections. In cases of severe diarrhea, it is essential to rehydrate and control electrolytes. In recurrent or refractory cases, fecal microbiota transplantation has emerged as a viable therapy to restore normal intestinal flora. Immunotherapy and monoclonal antibodies, such as bezlotoxumab, can also help prevent recurrence by targeting C. difficile toxins. PMCs can cause major problems such as toxic megacolon, colon perforation, and shock. Rapid detection and treatment are essential to achieve positive outcomes. The prognosis is mainly determined by the patient's age, comorbidities and the severity of the infection. Most patients recover with adequate care.. Preventative strategies, such as prudent use of antibiotics and infection control policies, are essential to reduce the prevalence of PMC in hospital settings.

In conclusion, pseudomembranous colitis (PMC) is a dangerous gastrointestinal illness caused mostly by broad-spectrum antibiotics disrupting intestinal flora.The condition causes symptoms ranging from moderate diarrhoea to life-threatening consequences including toxic megacolon and sepsis. Rapid diagnosis is crucial, as is immediate treatment, which often consists of removing the causative antibiotic, giving specific medication, and correcting hydration and electrolyte imbalances. Advanced medicines, provide treatments for recurring instances. Most patients recover with adequate care, but preventative strategies such as judicious antibiotic usage and tight infection control measures are still critical to reducing the burden of PMC in hospital settings.

References:

PMC, E. (2021). Europe PMC. [online] europepmc.org. Available at: https://europepmc.org/article/NBK/nbk1377.

Surawicz, C.M. and McFarland, L.V. (1999). Pseudomembranous colitis: causes and cures. Digestion, [online] 60(2), pp.91–100. doi:https://doi.org/10.1159/000007633.

Mayo Clinic (2019). Pseudomembranous colitis - Symptoms and causes. [online] Mayo Clinic. Available at: https://www.mayoclinic.org/diseases-conditions/pseudomembranous-colitis/symptoms-causes/syc-20351434.

Ellis, R.R. (n.d.). What Is Pseudomembranous Colitis? [online] WebMD. Available at: https://www.webmd.com/ibd-crohns-disease/ulcerative-colitis/pseudomembranous-colitis.