Localized disease diseases. Some diseases are capable of changing from local to disseminated diseases. Pneumonia, for example, is generally confined to one or both lungs but can become disseminated through sepsis, in which the microbe responsible for the pneumonia "seeds" the bloodstream or lymphatic system and is transported to distant sites in the body. When that occurs, the process is no longer described as a localized disease, but rather as a disseminated disease. Localized disease A localized disease is an infectious or neoplastic process that originates in and is confined to one organ system or general area in the body, such as
Gastrointestinal disease an endoscopy might be used to examine or take a biopsy from the stomach. The small and large intestines may be affected by infectious, autoimmune, and physiological states. Inflammation of the intestines is called enterocolitis, which may lead to diarrhea. Acute conditions affecting the bowels include infectious diarrhoea and mesenteric ischaemia. Causes of constipation may include faecal impaction and bowel obstruction, which may in turn be caused by ileus, intussusception, volvulus. Inflammatory bowel disease is a condition of unknown aetiology, classified as either Crohn's disease or ulcerative colitis, that can affect the intestines and other parts of the gastrointestinal tract.