Lab-tested diagnosis needed when treating patients with persistent diarrhea

(University of Texas Health Science Center at Houston) Persistent diarrhea, which is diarrhea that lasts at least 14 days, is an illness typically caused by parasites or bacteria and requires accurate diagnosis in order to determine what treatment to give, according to Herbert L. DuPont, M.D., director of the Center for Infectious Diseases at the University of Texas Health Science Center at Houston School of Public Health.