Conditions & Diseases, IMM-MAN
Whether we like it or not, living things are susceptible to any number of illnesses and conditions that can threaten or harm the health of those afflicted. Bacteria, viruses, and other microbiological agents are obvious challenges to health. Human disease may be acute, chronic, malignant, or benign, and it is usually indicated by signs and symptoms such as fever or vomiting. Additionally, diseases may be communicable (contagious) or noncommunicable; of the latter, the four major types identified by the World Health Organization are cancer, cardiovascular disease, chronic respiratory disease, and diabetes mellitus.
Conditions & Diseases Encyclopedia Articles By Title
immunodeficiency
immunodeficiency, defect in immunity that impairs the bodyâs ability to resist infection. The immune system may......
impact injury
impact injury, the damage caused by the collision of a body with a moving or stationary object. Impact injuries......
impetigo
impetigo, inflammatory skin infection that begins as a superficial blister or pustule that then ruptures and gives......
imposter syndrome
imposter syndrome, a persistent unjustified feeling that oneâs success is fraudulent. Imposter syndrome is characterized......
impotence
impotence, in general, the inability of a man to achieve or maintain penile erection and hence the inability to......
inborn error of metabolism
inborn error of metabolism, any of multiple rare disorders that are caused by an inherited genetic defect and that......
incidence
incidence, in epidemiology, occurrence of new cases of disease, injury, or other medical conditions over a specified......
Independent Living movement
The Independent Living movement promotes autonomy for people with disabilities to make decisions about their lives,......
infantile hemangioma
infantile hemangioma, a congenital benign tumour made up of endothelial cells (the cells lining the inner surface......
infarction
infarction, death of tissue resulting from a failure of blood supply, commonly due to obstruction of a blood vessel......
infection
infection, the process by which harmful microorganisms such as bacteria, viruses, fungi, or parasites enter cells......
infectious bovine keratoconjunctivitis
infectious bovine keratoconjunctivitis, an inflammation of the conjunctiva or the cornea of the eye in cattle as......
infectious disease
infectious disease, in medicine, a process caused by an agent, often a type of microorganism, that impairs a personâs......
- Introduction
- Rickettsias, Bacteria, Symptoms
- Fungal, Pathogens, Prevention
- Commensalism, Pathogens, Immunity
- Transmission, Prevention, Control
- Occupation, Commerce, Prevention
- Immune Response, Pathogens, Prevention
- Natural Immunity, Acquired Immunity
- Immunization, Prevention, Vaccines
- Polio Vaccine, Prevention, Eradication
- Hepatitis B, Vaccine, Prevention
inferiority complex
inferiority complex, a psychological sense of inferiority that is wholly or partly unconscious. The term has been......
infertility
infertility, the inability of a couple to conceive and reproduce. Infertility is defined as the failure to conceive......
inflammation
inflammation, a response triggered by damage to living tissues. The inflammatory response is a defense mechanism......
influenza
influenza, an acute viral infection of the upper or lower respiratory tract that is marked by fever, chills, and......
Influenza Pandemic of 1918â19 Chart
This infographic explains what influenza and pandemics are and how the influenza pandemic of 1918â19 spread. That......
insect bite and sting
insect bite and sting, break in the skin or puncture caused by an insect and complicated by introduction into the......
insomnia
insomnia, the inability to sleep adequately. Causes may include poor sleeping conditions, circulatory or brain......
intellectual disability
any of several conditions characterized by subnormal intellectual functioning and impaired adaptive behavior that......
intestinal squeeze
intestinal squeeze, pain and possible injury to the small or large intestine caused by expansion of trapped gases......
iodine deficiency
iodine deficiency, condition in which iodine is insufficient or is not utilized properly. Iodine is an element......
ionizing radiation injury
ionizing radiation injury, tissue destruction or changes caused by deeply penetrating electromagnetic waves of......
iron-deficiency anemia
iron-deficiency anemia, anemia that develops due to a lack of the mineral iron, the main function of which is in......
Is It Safe to Reopen Schools During the COVID-19 Pandemic?
This article was originally published on August 19, 2020, during the first year of the COVID-19 pandemic, when......
Is Spontaneous Human Combustion Real?
Late at night on Christmas Eve 1885, in the small farming town of Seneca, Illinois, a woman named Matilda Rooney......
Is There a Cure for HIV Infection?
No, there is no cure yet for infection with HIV, or human immunodeficiency virus. In fact, despite multiple reports......
Itard, Jean-Marc-Gaspard
Jean-Marc-Gaspard Itard was a French physician noted for his work with the deaf and with the âwild boy of Aveyron.â......
itching
itching, a stimulation of free nerve endings, usually at the junction of the dermis and epidermis of the skin,......
Janet, Pierre
Pierre Janet was a French psychologist and neurologist influential in bringing about in France and the United States......
joint disease
joint disease, any of the diseases or injuries that affect human joints. Arthritis is no doubt the best-known joint......
kala-azar
kala-azar, infectious disease that is a type of leishmaniasis...
Kaposi sarcoma
Kaposi sarcoma, rare and usually lethal cancer of the tissues beneath the surface of the skin or of the mucous......
Kawasaki syndrome
Kawasaki syndrome, rare, acute inflammatory disease of unknown origin that is one of the leading causes of acquired......
keloid
keloid, benign tumour and chronic skin disorder in which excessive scar tissue (mainly collagen) forms a smooth......
keratitis
keratitis, inflammation of the cornea, the transparent domelike portion of the eyeball in front of the iris and......
keratosis
keratosis, any protuberance on the skin resulting from the overdevelopment of the horny outermost covering of the......
Kerlin, Isaac Newton
Isaac Newton Kerlin was an American physician and administrator who was a strong proponent of institutionalizing......
kernicterus
kernicterus, severe brain damage caused by an abnormal concentration of the bile pigment bilirubin in brain tissues......
ketosis
ketosis, metabolic disorder marked by high levels of ketones in the tissues and body fluids, including blood and......
kidney failure
kidney failure, partial or complete loss of kidney function. Kidney failure is classified as acute (when the onset......
kidney stone
kidney stone, concretion of minerals and organic matter that forms in the kidneys. Such stones may become so large......
kingâs evil
kingâs evil, scrofula (q.v.), or struma, a tuberculous swelling of the lymph glands, once popularly supposed to......
kleptomania
kleptomania, recurrent compulsion to steal without regard to the value or use of the objects stolen. Although widely......
Klinefelter syndrome
Klinefelter syndrome, disorder of the human sex chromosomes that occurs in males. Klinefelter syndrome is one of......
knee injuries
knee injuries, the common afflictions of the knee, a relatively fragile joint, as it is exposed to stress in daily......
Korsakoff syndrome
Korsakoff syndrome, neurological disorder characterized by severe amnesia (memory loss). Many cases result from......
Kraepelin, Emil
Emil Kraepelin was a German psychiatrist, one of the most influential of his time, who developed a classification......
kuru
kuru, infectious fatal degenerative disorder of the central nervous system found primarily among the Fore people......
kwashiorkor
kwashiorkor, condition caused by severe protein deficiency. Kwashiorkor is most often encountered in developing......
labyrinthitis
labyrinthitis, inflammation, either acute or chronic, of the inner ear (the labyrinth). It is often a complication......
laceration
laceration, tearing of the skin that results in an irregular wound. Lacerations may be caused by injury with a......
lactose intolerance
lactose intolerance, inability to digest lactose, the predominant sugar in dairy products. It affects people by......
laryngeal cancer
laryngeal cancer, malignant disease of the larynx (voice box). The most common type of malignant tumor identified......
Lathrop, Julia Clifford
Julia Clifford Lathrop was an American social welfare worker who was the first director of the U.S. Childrenâs......
lead poisoning
lead poisoning, deleterious effect of a gradual accumulation of lead in body tissues, as a result of repeated exposure......
learning disabilities
learning disabilities, Chronic difficulties in learning to read, write, spell, or calculate, which are believed......
Legionnaire disease
Legionnaire disease, form of pneumonia caused by the bacillus Legionella pneumophila. The name of the disease (and......
leishmaniasis
leishmaniasis, human protozoal infection spread by the bite of a sand fly (subfamily Phlebotominae). Leishmaniasis......
lens dislocation
lens dislocation, abnormal position of the crystalline lens of the eye. The dislocation, which may be congenital,......
leprosy
leprosy, chronic infectious disease that affects the skin, the peripheral nerves (nerves outside the brain and......
leptospirosis
leptospirosis, acute systemic illness of animals, occasionally communicable to humans, that is characterized by......
Lesch-Nyhan syndrome
Lesch-Nyhan syndrome, hereditary metabolic disorder affecting the central nervous system and characterized by incoordination,......
lesion
lesion, in physiology, a structural or biochemical change in an organ or tissue produced by disease processes or......
leukemia
leukemia, a cancer of the blood-forming tissues characterized by a large increase in the numbers of white blood......
leukocytosis
leukocytosis, abnormally high number of white blood cells (leukocytes) in the blood circulation, defined as more......
leukopenia
leukopenia, abnormally low number of white blood cells (leukocytes) in the blood circulation, defined as less than......
leukoplakia
leukoplakia, precancerous tumour of the mucous membranes, usually seen in the mouth or on the tongue or cheeks,......
leukorrhea
leukorrhea, flow of a whitish, yellowish, or greenish discharge from the vagina of the female that may be normal......
lipid storage disease
lipid storage disease, any of a group of relatively rare hereditary disorders of fat metabolism, characterized......
List of Deadliest Diseases
Throughout history, certain diseases have left an indelible mark on humanityâclaiming millions of lives, straining......
List of Most Contagious Diseases
Infectious diseases have played a powerful role in shaping human history and still affect lives todayâfrom sweeping......
List of Vaccine-Preventable Diseases
Vaccines are among the most effective tools available in modern medicine, offering protection against a wide range......
listeriosis
listeriosis, disease caused by the bacterium Listeria monocytogenes. The bacterium has been isolated from humans......
liver cancer
liver cancer, any of several forms of disease characterized by tumors in the liver. Benign liver tumors remain......
louping ill
louping ill, viral disease mainly of sheep and red grouse, causing inflammation of the brain and spinal cord. The......
lumbago
lumbago, pain in the lower (lumbar) portion of the back. Lumbago is considered by health professionals to be an......
lung cancer
lung cancer, disease characterized by uncontrolled growth of cells in the lungs. Lung cancer was first described......
lung congestion
lung congestion, distention of blood vessels in the lungs and filling of the alveoli with blood as a result of......
lung infarction
lung infarction, death of one or more sections of lung tissue due to deprivation of an adequate blood supply. The......
lupus erythematosus
lupus erythematosus, an autoimmune disorder that causes chronic inflammation in various parts of the body. Three......
Luria, A R
A.R. Luria was a Soviet neuropsychologist. After earning degrees in psychology, education, and medicine, he became......
lycanthropy
lycanthropy, (from Greek lykos, âwolf â; anthropos, âmanâ), mental disorder in which the patient believes that......
Lyme disease
Lyme disease, tick-borne bacterial disease that is named for the town in the U.S. state of Connecticut in which......
lymphangitis
lymphangitis, bacterial infection of the lymphatic vessels. The condition is caused by streptococcus or staphylococcus......
lymphedema
lymphedema, an abnormal condition in which poor function of the lymphatic system allows fluid to build up in the......
lymphocytic choriomeningitis
lymphocytic choriomeningitis, inflammation of the meninges (membranes covering the central nervous system) and......
lymphogranuloma venereum
lymphogranuloma venereum, infection of lymph vessels and lymph nodes by the microorganism Chlamydia trachomatis.......
lymphoma
lymphoma, any of a group of malignant diseases of the lymphatic system, usually starting in the lymph nodes or......
lysogeny
lysogeny, type of life cycle that takes place when a bacteriophage infects certain types of bacteria. In this process,......
Machiavellianism
Machiavellianism, the political theory of the Italian statesman and writer NiccolĂČ Machiavelli (1469â1527), as......
macroglossia
macroglossia, enlargement of the tongue, due to overdevelopment of the muscle or the accumulation of material within......
macular degeneration
macular degeneration, group of blinding disorders that cause the gradual deterioration of the retina in the eye.......
magnesium deficiency
magnesium deficiency, condition in which magnesium is insufficient or is not utilized properly. Magnesium is a......
major depressive disorder
major depressive disorder, mental disorder characterized by persistent hopelessness, disinterest in and lack of......
malaria
malaria, serious relapsing infection in humans, characterized by periodic attacks of chills and fever, anemia,......
Malformation
Malformation, in biology, irregular or abnormal structural development. Malformations occur in both plants and......
malnutrition
malnutrition, physical condition resulting either from a faulty or inadequate diet (i.e., a diet that does not......
mandibulofacial dysostosis
mandibulofacial dysostosis, a rare, genetic disorder, inherited as an autosomal-dominant trait and characterized......