WAnorectal abscess
WAnismus
WBezoar
WBlind loop syndrome
WBowel infarction
WBowel obstruction
WCampylobacteriosis
WCholera
WChronic enteropathy associated with SLCO2A1 gene
WCoeliac disease
WCronkhite–Canada syndrome
WCryptitis
WCuffitis
WDistal intestinal obstruction syndrome
WDiversion colitis
WDuodenal atresia
WEnteric neuropathy
WEnteropathy-associated T-cell lymphoma
WEosinophilic gastroenteritis
WEpiploic appendagitis
WFecal incontinence
WForeign body in alimentary tract
WFundic gland polyposis
WGastrointestinal bleeding
WGlobus pharyngis
WHematochezia
WHirschsprung's disease
WInflammatory bowel disease
WIntestinal metaplasia
WIntestinal parasite infection
WIntestinal spirochetosis
WIschemic colitis
WKeriorrhea
WLower gastrointestinal bleeding
WMalabsorption
WMegacolon
WMelanosis coli
WMicrovillous inclusion disease
WNecrotizing enterocolitis
WNeurogenic bowel dysfunction
WPancolitis
WPerianal hematoma
WPeutz–Jeghers syndrome
WPharyngitis
WPneumatosis intestinalis
WProctocolitis
WProtein losing enteropathy
WRadiation proctitis
WSmall intestinal bacterial overgrowth
WStercoral perforation
WSuperior mesenteric artery syndrome
WUpper gastrointestinal bleeding
WWhipple's disease