Irritable Bowel Syndrome (IBS) - a prevalent condition in India, gravely affects the life of individuals. IBS is a functional bowel disorder characterized by abdominal pain or discomfort associated with defecation, change in bowel habits – bowel frequency and consistency. 

IBS prevalence in India is 4.2-7.9%, and young males show a higher predilection – with predominant upper abdominal symptoms. The prevalence is greater in Western countries, where IBS is more common among young females – with predominant lower abdominal symptoms. 

Diagnosis – Rome IV Criteria

Recurrent abdominal pain – at least once a week over consequent 3 months – associated with 2/more of the following symptoms:

·        Related to defecation

·        Changes in stool frequency

·        Change is stool form/consistency or appearance

Symptom persistence over the past three months with onset at least, 6 months prior. 

Red Flag Signs

·        Age > 50 years, with a sudden change in bowel habits

·        Overt gastrointestinal (GI) bleeding – malena, hematochezia

·        Nocturnal pain/bowel motion

·        Unintentional weight loss

·        Family history of colorectal cancer or inflammatory bowel disease (IBD)

·        Palpable abdominal mass or lymphadenopathy

·        Iron deficiency anemia 

·        Positive for fecal occult blood 

The stool form can be categorized using theBristol Stool Chart – to ascertain the constipation/diarrhea type.

Pathogenesis

·        Physiology

·        Psychosocial environment

·        Genetic predisposition

·        Immune dysregulation

·        Brian-gut axis alteration

·        Altered gut microbiota or small intestinal bacterial overgrowth (SIBO)

·        Environmental pollution

·        Visceral hypersensitivity

·        Changes in GI motility

·        Intestinal motility

SIBO is characterized by excessive bacteria in the small intestine – >10³ CFU/ml. Treatment involves dietary modifications, antibiotics, probiotics, prokinetics, and fecal microbiota transplantation.

Comorbidities

IBS can present in patients with anxiety disorders. The diagnosis rate ranges from 54%-94%.

Treatment

Antispasmodics in IBS: 

·        Anticholinergics (improve abdominal pain and IBS symptom score) – Hyoscine, Dicyclonime, Clinidium

·        Calcium-channel blockers – Pepermint oil, Otilonium, Pinaverium

·        Sodium-channel blockers – Meberverine

·        Decreased GI spasticity and motility

Other pharmacological options:

·        SSRIs

·        Tricyclic antidepressants

·        Peppermint oil

In summary, IBS is diagnosed through a detailed history and symptom-based criteria that consider – abdominal pain/discomfort; relief with defecation; and changes in bowel frequency and consistency. The evaluation involves – assessing red-flag symptoms, ordering appropriate investigations, and a 6-week follow-up of the clinical and laboratory parameters. 

The therapy aims to alleviate symptoms. Individualized treatment strategies and patient counseling are warranted. Establishing patients’ trust and compliance are key to improving prognosis. The choice of intervention should be based on the predominant symptom, disorder severity, comorbidities, and the patient’s characteristics and preferences.