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Overview Necrotizing enterocolitis (NEC) is an inflammation in the intestines (usually the colon) that can be life-threatening if not treated right away. NEC may affect only the lining of the intestine or its entire thickness. The damage caused by NEC to the intestinal tissues can cause a hole in the …

Definition              Neuropathic pain is defined as pain caused by a lesion or dysfunction in the nervous system. There is no noxious (pain causing) stimulus that is causing the pain. Rather, the pain results from inappropriate signals in the nervous system. Unlike physiologic pain, which serves to warn and protect individuals …

Description Neurocysticercosis, the infection caused by the larval form of the tapeworm Taenia solium, is the most common parasitic disease of the central nervous system and the most common cause of acquired epilepsy worldwide. The larval cysts can infect various parts of the body causing a condition known as cysticercosis. …

Definition Niemann-Pick disease (NPD) is a group of inherited metabolic disorders in which harmful quantities of a fatty substance (lipids) accumulate in the spleen, liver, lungs, bone marrow, and brain. There is a deficiency of a lysosomal enzyme called acid sphingomyelinase or disturbance in cholesterol breakdown or transportation. This enzyme …

Definition Norovirus infection is the most common cause of infection in gastrointestinal outbreaks. It causes sudden onset of nausea, vomiting, and diarrhea.  Sometimes it may also cause stomach cramping. In addition, the person may feel tired, muscle ache, headache, and low-grade fever. Norovirus is a very contagious virus that can …

Definition Nephrotic syndrome is the state that the kidney excretes large amounts of protein in the urine. It is usually caused due to the damage in the cluster of blood vessels in the kidney that filters waste materials from the blood. It causes swelling (edema) in ankles, legs and feet. …

What is night blindness? Night blindness (Nyctalopia) is the inability to see well at night or in poor light. It is not a disease in itself, but rather a symptom of an underlying problem, usually a retina problem. It is common for patients who are myopic to have some difficulties …

Definition Nocardiosis is a rare infection caused by the Nocardia asteroides bacterium. This type of bacteria can be found in the soil and water of regions around the world. People may become infected with this bacteria when they inhale it or when the bacteria enter an open wound. The infection …