A rare, but fatal infection of the central nervous system caused by Naegleria fowleri, an ameba that inhabits freshwater lakes, rivers and hot springs. The disease results when ameba-contaminated water incidentally enters the nose during aquatic activities and amebas migrate to the brain. Symptoms can include headache, fever, stiff neck and seizures. Most cases occur in the summer and among children. High water temperature and lowered water level may lead to increased risk of infection. Recommendations for prevention include holding the nose shut or using nose clips when jumping or diving into bodies of fresh water.
- Primary amenorrhea
Absence of menstruation. Amenorrhea is conventionally divided into primary and secondary amenorrhea. With primary amenorrhea, menstruation never takes place. It fails to occur at puberty. With secondary amenorrhea, menstruation starts but then stops. The absence of menstruation during pregnancy is a form of physiologic amenorrhea, physiologic in the sense that it is completely normal and […]
- Primary amyloidosis
A disorder of plasma cells (special white blood cells that produce antibodies), this is one of a group of diseases (called amyloidosis) in which protein deposits (amyloid) accumulate in one or more organ systems in the body. Primary amyloidosis is the most common type of amyloidosis in many countries including the U.S. The protein deposits […]
- Primary atelectasis
Failure of the lung to expand fully at birth. In contrast to secondary atelectasis in which there is partial or complete collapse of a lung that once had expanded, as may happen after chest surgery.
- Primary biliary cirrhosis (PBC)
A liver disease caused by an abnormality of the immune system. Small bile ducts within the liver become inflamed and obliterated. Backup of bile causes intense skin itching and yellowing of the skin (jaundice). Lack of bile decreases absorption of calcium and vitamin D, leading to osteoporosis. Cirrhosis (scarring of the liver) develops over time.
- Primary care
A patient’s main source for regular medical care, ideally providing continuity and integration of health care services. All family physicians, and many pediatricians and internists, practice primary care. The aims of primary care are to provide the patient with a broad spectrum of preventive and curative care over a period of time and to coordinate […]