Types of Dysentery

Doctors split dysentery by the germ responsible, because the germ decides both the illness pattern and the medicine that ends it.

Bacillary dysentery (shigellosis). Caused by Shigella bacteria. This is the explosive form: sudden fever, cramping, and frequent small stools streaked with blood and mucus, with marked tenesmus. It is ferociously contagious - tiny infecting doses - so it moves through families and institutions fast. Children are hit hardest, and a febrile seizure can occasionally be the first sign in a small child. The illness usually peaks within a week but needs antibiotics to shorten it, reduce complications, and stop the patient spreading it to others.

Amoebic dysentery (amoebiasis). Caused by the parasite Entamoeba histolytica, swallowed as cysts in contaminated water or food. The bowel illness is usually slower and less feverish - colicky pain, bloody-mucoid stools, sometimes alternating with symptom-free stretches. Its defining danger is elsewhere: the amoeba can burrow into blood vessels and seed the liver, forming an abscess - fever, right-upper-abdominal pain, a tender enlarged liver, arriving weeks or even months after the bowel illness. Untreated amoebiasis can also smolder into chronic gut symptoms mistaken for irritable bowel. Treatment needs a two-step approach: a tissue-active drug (metronidazole) followed by a luminal agent that clears the cysts from the bowel - stopping after the first drug leaves the cysts behind.

Other dysentery-like infections. Campylobacter, invasive E. coli, Giardia and Balantidium can produce bloody or mucoid diarrhea that resembles dysentery; stool tests sort them out.

There is also a chronic, non-infective look-alike: ulcerative colitis and other inflammatory bowel diseases cause bloody mucoid stools too. When "dysentery" keeps recurring or never fully settles, the question changes from "which germ" to "is this infection at all" - and that question needs a gastroenterologist.