Pap Smear

Pap Smear: A screening test for cervical cancer based on the examination of cells under the microscope. The cells are collected from the cervix, smeared on a slide and specially stained to reveal premalignant (before cancer) and malignant (cancer) changes as well as changes due to noncancerous conditions such as inflammation from infections. Also called a Pap smear.

The Pap technique was developed by and named after George Papanicolaou (1883-1962), a Greek-born physician and scientist who moved to the U.S. In 1923, while looking at vaginal smears from women with cervical cancer, Papanicolaou saw cancer cells. After two decades of research on this subject, he reported in 1943 that both cervical and uterine cancer could be detected in their early stages with this test that has, since its inception, saved innumerable lives.

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Chronic wasting disease

Chronic wasting disease: A transmissible spongiform encephalopathy (TSE) of North American deer and elk, a progressive neurodegenerative disorder that produces spongiform changes in the brain and chronic weight loss leading to the death of these animals. There is no known relationship between chronic wasting disease (CWD) and any other TSE of animals or people.

There are three main theories on the nature of the agent that causes CWD: (1) the agent is a prion, an abnormal form of a normal protein (known as cellular prion protein) most commonly found in the central nervous system. The abnormal prion protein “infects” the host by promoting the conversion of normal cellular protein to the abnormal form; (2) the agent is an unconventional virus; (3) the agent is a virino, or “incomplete” virus composed of nucleic acid protected by host proteins. The CWD agent is smaller than most viral particles and does not evoke any detectable immune response or inflammatory reaction in the host animal.

Most cases of CWD occur in adult animals. The disease is progressive and always fatal. The most obvious and consistent clinical sign of CWD is weight loss over time. Behavioral changes also occur in the majority of cases, including decreased interactions with other animals in the pen, listlessness, lowering of the head, blank facial expression, and repetitive walking in set patterns within the pen. In elk, behavioral changes may also include hyperexcitability and nervousness. Affected animals continue to eat grain but may show decreased interest in hay. Excessive salivation and grinding of the teeth are seen. Most deer show increased drinking and urination.

Diagnosis is confirmed by necropsy examination and testing. On microscopic examination, lesions of CWD in the central nervous system resemble those of other spongiform encephalopathies. In addition, using a technique called immunohistochemistry, scientists test brain tissues for the presence of the abnormal prion protein.

Species that have been affected with CWD include Rocky Mountain elk, mule deer, white-tailed deer, and black-tailed deer. Other ruminant species, including wild ruminants and domestic cattle, sheep, and goats, have been housed in wildlife facilities in direct or indirect contact with CWD-affected deer and elk. No cases of CWD or other TSE’s have been detected in these other ruminant species.

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Parkinson disease

Parkinson disease: A slowly progressive neurologic disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40. Also known as paralysis agitans and shaking palsy.

From a genetic viewpoint it is now clear that Parkinson disease is heterogeneous. It is not one, but a number of diseases. Genes appear to be involved in all forms of Parkinson disease. See also: Parkinson disease gene.

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Sneeze: 1. As a verb, to suddenly expel air through the nose and mouth by an involuntary contraction of the muscles of expiration.
2. As a noun, the act of sneezing.

Sneezing is commonly caused by irritation of the nasal passages, as from pollens, house dust, pepper, or other particles. The sound of the word “sneeze” suggests the act. See also: Achoo syndrome; Photic sneeze reflex.

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Milwaukee brace

Milwaukee brace: One of the two main types of braces used to treat the lateral curve of the spine in scoliosis. This brace can be worn to correct any curve in the spine.

The brace can be custom made or can be made from a pre-fabricated mold. All braces must be selected for the specific curve problem and fitted to each patient. To have their intended effect (to keep a curve from getting worse), the brace must be worn every day for the full number of hours prescribed by the doctor until the child stops growing.

The other type of brace for scoliosis is called a thoracolumbosacral orthosis (TLSO).

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Measles: An acute and highly contagious viral
disease characterized by fever, runny nose, cough, red eyes, and a
spreading skin rash. Measles, also known as rubeola, is a potentially
disastrous disease. It can be complicated by ear infections,
pneumonia, encephalitis (which can cause convulsions, mental
retardation, and even death), the sudden onset of low blood platelet
levels with severe bleeding (acute thrombocytopenic purpura), or a
chronic brain disease that occurs months to years after an attack of
measles (subacute sclerosing panencephalitis).

During pregnancy,
exposure to the measles virus may trigger miscarriage or premature

Treatment includes rest, calamine lotion or other anti-
itching preparations to soothe the skin, non-aspirin pain relievers
for fever, and in some cases antibiotics. Measles can often be
prevented through vaccination. Also known as hard measles, seven-day
measles, eight-day measles, nine-day measles, ten-day measles,

See also measles encephalitis; measles immunization;
measles syndrome, atypical; MMR.

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Rabies: A potentially fatal viral infection that attacks the central nervous system. Rabies is carried by wild animals (particularly bats and raccoons) and finds its way to humans by many routes. Most cases of rabies can be traced to animal bites, but cases have been documented in which the virus was inhaled in bat caves, contracted in lab accidents, or received from transplanted donor tissue. Symptoms include fever, aching muscles, and headache, potentially progressing to inflammation of the brain, confusion, seizures, paralysis, coma, and death. There is no cure for rabies after it has settled in the brain, so immediate emergency care for any suspicious animal contact is imperative. Rabies immunoglobulin shots, antibiotics, and rabies vaccine may be used immediately after contact with a suspected rabies carrier. To prevent rabies, pets should be vaccinated against the virus, and people should avoid contact with wild or unknown animals. A human rabies vaccine is available, but it is recommended only for those in high-risk occupations (such as game wardens, zookeepers, and animal control officers).

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Plague: The plague is an infectious disease due to a
bacteria called Yersinia pestis.

Y. pestis mainly infects rats and other rodents. Rodents are the
prime reservoir for the bacteria. Fleas function as the prime vectors
carrying the bacteria from one species to another. The fleas bite the
rodents infected with Y. pestis and then they bite people and so
transmit the disease to them.

Transmission of the plague to people can also occur from eating
infected animals such as squirrels (e.g., in the southeastern U.S.)
Once someone has the plague, they can transmit it to another person
via aerosol droplets.

HistoryYersinia is named after a Swiss bacteriologist Alexandre-
Emile-Jean Yersin (1863-1943) who identified it in 1894 after a trip
to Hong Kong looking for the agent that was killing thousands of
people in southern China. The same discovery was made at the same
time by a Japanese bacteriologist Shibasaburo Kitasako.

The plague has been responsible for devastating epidemics. The
disease occurs endemically (at a consistent but low level) in many
countries including the United States. “La Peste” (The
Plague), a novel (1947) by the Nobel Prize-winning French writer
Albert Camus (1913-1960) is set in the Algerian city of Oran overrun
by a deadly epidemic of the plague.

Bioterrorism — The General Accounting Office, the investigative arm of the US Congress, in a 1999 report considered plague to be a “possible, but not likely” biologic threat for terrorism, as it is difficult to acquire a suitable strain of Y. pestis and to weaponize and distribute it. Seed stock is difficult to acquire and to process and heat, disinfectants and sunlight render it harmless.

The plague is also known as pest and pestis.

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Herpes: A family of viruses. Herpes also refers to infection with one of the human herpesviruses, especially herpes simplex types 1 and 2.

Herpes simplex type 1, also known as human herpesvirus 1 (HHV-1), causes cold sores and fever blisters in the mouth and around it.

Herpes simplex type 2, also known as human herpesvirus 1 (HHV-1), causes genital herpes, a sexually transmitted disease (STD). Genital herpes is characterized by sores in the genital area.

Both herpes simplex types 1 and 2 are capable of causing systemic disease including encephalitis (infection of the brain) in someone who is immunodeficient.

The treatment of most infections with herpes simplex infections is by topical or oral anti-viral medication, although intravenous therapy is required to treat infections of the brain (encephalitis).

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Ewing sarcoma

Ewing sarcoma: A malignant tumor that arises in a primitive nerve cell within bone or soft tissue and affects children and adolescents, especially between ages 10 and 20. Ewing sarcoma usually appears in the large bones of the arms and legs and the flat bones of the pelvis, spine, and ribs. Treatments include chemotherapy, surgery, and radiation therapy. The primitive nerve cell from which Ewing sarcoma arises also gives rise to a number of tumors, known as the Ewing family of tumors, which include Ewing sarcoma of bone, extraosseus (nonbone) Ewing sarcoma, primitive neuroectodermal tumor (PNET), and Askin tumor (PNET of the chest wall). Most Ewing family tumors have a translocation between chromosomes 11 and 22 that results in the fusion of the EWS gene on chromosome 22 with the transcription factor gene FLI1 on chromosome 11, leading to the production of a chimeric (fusion) protein. The remaining tumors in the Ewing family engage the EWS gene in other translocations that lead to formation of chimeric proteins. In all cases the chimeric protein is oncogenic; that is, it is responsible for the malignancy.

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