A culture of an infected personís stool sample can identify the Shigella bacteria. The laboratory can also do special tests to tell which species of Shigella the person has and which antibiotics would be best to treat it.
Although shigellosis is usually a self-limited illness, antibiotics can shorten the course, and in the most serious cases, might be life-saving. When therapy is indicated, a fluoroquinolone antibiotic is the recommended first-line treatment for non-pregnant adults, such as ciprofloxacin 500 mg twice daily for three days. Alternative antimicrobial agents include trimethoprim-sulfamethoxazole, azithromycin, and ceftriaxone. Antidiarrheal agents such as loperamide (Imodium) or diphenoxylate with atropine (Lomotil) are likely to make the illness worse and should be avoided.
While shigellosis usually resolves in 5 to 7 days, it may be several months before an affected personís bowel habits are entirely normal. In some persons, especially young children, the elderly, and immune compromised persons, the diarrhea can be so severe that the affected person needs to be hospitalized. It is estimated that over 6,000 hospitalizations for shigellosis occur each year in the U.S. Complications of shigellosis include severe dehydration, seizures in small children, rectal bleeding, and invasion of the blood stream by the bacteria. In the U.S., it is estimated that about 70 persons die yearly from shigellosis, with small children and the elderly at greatest risk of dying.