Symptoms of Crohn's disease develop gradually and may not be apparent during the early stage of the disease, explains Mayo Clinic. Common symptoms include a low-grade fever, fatigue, diarrhea, abdominal cramping and pain, and bloody stools.
Some patients with Crohn's disease develop mouth sores, lose weight due to a reduced appetite or experience drainage around the anus, according to Mayo Clinic. Abdominal pain and cramping can cause slight to severe discomfort that may gradually lead to vomiting and nausea. Severe symptoms of the disease include inflammation of the joints, eyes, skin, liver or bile ducts, and delayed sexual development or growth in children.