Jarusa.Com - Fun Sites for Sore Eyes

Information on Disease


In common usage, a disease is any abnormal condition of the body or mind that causes discomfort or dysfunction. Often used metaphorically for pathological conditions of other things, as in disease of society. Stricter medical usage sometimes distinguishes a disease, which has a known specific cause or causes (called its etiology), from a syndrome, which is a collection of symptoms that often occur together but for which there is no known cause. Also, many medical terms that describe symptoms are often called "diseases", especially when the cause of the symptom is unknown.

The largest and best-known category, infectious diseases are those caused by transmissible infectious agents such as bacteria, fungi, parasites, viruses, and prions. Closely related though not infectious diseases in the strictest sense are parasitic diseases caused by protozoa and worms. There are also genetic diseases caused by the presence or absence of genes in the affected person's DNA; toxic diseases caused by exposure to environmental toxins such as heavy metals; nutritional diseases caused by lack or deficiency in certain nutrients; conditions caused by injury, malformation, or disuse of parts of the body; autoimmune diseases caused by immune system attacks on the body's own tissue; diseases caused by the patient's own beliefs; and diseases causes by combinations of these, and of course totally unknown causes.

The World Health Organization publishes a comprehensive list of diseases known as International Statistical Classification of Diseases and Related Health Problems (ICD).

See also:

External links

List of infectious diseases

Health Science > Medicine > Infectious Diseases

Human infectious diseases grouped by causative agent and alphabetically

Table of contents
1 Viral infectious diseases
2 Bacterial infectious diseases
3 Parasitic infectious diseases
4 Fungal infectious diseases
5 Prion infectious diseases
6 Infectious Disease Theory

Viral infectious diseases

AIDS -- AIDS Related Complex -- Chickenpox or Varicella -- Common cold -- Cytomegalovirus Infection -- Colorado tick fever -- Dengue fever -- Ebola haemorrhagic fever -- Epidemical parotitis -- Flu -- Hand, Foot and Mouth Disease -- Hepatitis -- Herpes zoster -- Influenza -- Lassa fever -- Measles -- Marburg haemorrhagic fever -- Mononucleosis -- Mumps -- Poliomyelitis -- Progressive multifocal leukencephalopathy -- Rabies -- Rubella -- SARS -- Smallpox or variola -- Viral meningitis -- West Nile disease -- Yellow fever

Bacterial infectious diseases

Anthrax -- Bacterial Meningitis -- Brucellosis -- Bubonic plague -- Campylobacteriosis -- Cholera -- Diphtheria -- Epidemic Typhus -- Gonorrhea -- Hansen's Disease -- Legionellosis -- Leprosy -- Leptospirosis -- Listeriosis -- Lyme Disease -- MRSA infection -- Nocardiosis -- Pertussis -- Pneumococcal pneumonia -- Psittacosis -- Q fever -- Rocky Mountain Spotted Fever or RMSF -- Salmonellosis -- Scarlet Fever -- Shigellosis -- Syphilis -- Tetanus -- Trachoma -- Tuberculosis -- Tularemia -- Typhoid Fever -- Typhus -- Whooping Cough

Parasitic infectious diseases

African trypanosomiasis -- Amebiasis -- Ascariasis -- Chagas Disease -- Clonorchiasis -- Cysticercosis -- Diphyllobothriasis -- Dracunculiasis -- Echinococcosis -- Enterobiasis -- Fascioliasis -- Fasciolopsiasis -- Filariasis -- Giardiasis -- Gnathostomiasis -- Hymenolepiasis -- Kala-azar -- Leishmaniasis -- Malaria -- Onchocerciasis -- Pediculosis -- Pinworm Infection -- Scabies -- Schistosomiasis -- Toxocariasis -- Toxoplasmosis -- Trichinellosis -- Trichinosis -- Trichuriasis -- Trypanosomiasis

Fungal infectious diseases

Aspergillosis -- Blastomycosis -- Candidiasis -- Coccidioidomycosis -- Cryptococcosis -- Cryptosporidiosis -- Histoplasmosis

Prion infectious diseases

Bovine Spongiform Encephalopathy -- Creutzfeldt-Jakob Disease -- Kuru

Infectious Disease Theory

Basic reproductive rate

Autoimmune disorder

An autoimmune disorder arises from an overactive immune response of the body against substances and tissues normally present in the body. The causes of autoimmune disorders are still obscure, and most of these disorders are probably the result of multiple circumstances: for example, a genetic predisposition triggered by an infection.

Women tend to be affected more often by autoimmune disorders, nearly 79% of autoimmune disease patients in the USA are women [1]. It is not known why this is the case, although hormone levels have been shown to affect the severity of the disease [1].

See also : Immune system.

Below is a listing of actual and suspected autoimmune disorders, with brief descriptions and pointers to full articles.

Disorders believed to be autoimmune disorders

  • Guillain-Barré syndrome (GBS), is an acquired immune-mediated inflammatory disorder of the peripheral nervous system (e.g. not the brain and spinal column). It is also called acute inflammatory demyelinating polyneuropathy, acute idiopathic polyradiculneuritis, acute idiopathic polyneuritis and Landry's ascending paralysis.

  • Lupus erythematosus is an is a chronic (long-lasting) autoimmune disease where the immune system, for unknown reasons, becomes hyperactive and attacks normal tissue. This attack results in inflammation and brings about symptoms.

  • Multiple Sclerosis is a disorder of the central nervous system (brain and spinal cord), which is characterised by decreased nerve function due to myelin loss and secondary axonal damage.

  • Myasthenia gravis is a disorder of neuromuscular transmission leading to fluctuating weakness and fatigue. Weakness is caused by circulating antibodies that block acetylcholine receptors at the neuromuscular junction.

  • Optic neuritis is an inflammation of the optic nerve that may cause a complete or partial loss of vision.

  • Psoriasis is a skin disorder in which rapidly multiplying skin cells produce itchy, scaly inflamed patches on the skin.

  • Rheumatoid Arthritis is an autoimmune disorder that causes the body's immune system to attack the bone joints. It is a disabling condition, and often thought of as a disease.

  • Graves' disease is the commonest form of hyperthyroidism, and is caused by anti-thyroid antibodies that have the effect of stimulating the thyroid into overproduction of thyroid hormone

  • Type I Diabetes appears to be the result of an autoimmune attack on the islet cells of the pancreas.

  • Aplastic anemia may sometimes be caused by an autoimmune attack on the bone marrow.

  • Reiter's Syndrome seems to be an autoimmune attack on various body systems in response to a bacterial infection and the body's confusion over the HLA-B27 marker

  • Primary biliary cirrhosis appears to be an autoimmune disease that affects the biliary epithelial cells (BECs) of the small bile duct in the liver. The cause is yet to be determined but most of the patients (<90%) seem to have auto-mitochondrial antibodies (AMAs) against pyruvate dehydrogenase complex (PDC), an enzyme that is found in the mitochondria.

Disorders that might be autoimmune related

  • Crohn's disease is an inflammatory bowel disease characterized by chronic inflammation of the intestinal tract. Major symptoms include abdominal pain and diarrhea.

  • Interstitial cystitis is a urinary bladder disease characterised by pelvic pain, urinary frequency (as often as every 30 minutes), pain with sexual intercourse, but no pain with urination.

  • Neuromyotonia is spontaneous muscular activity resulting from repetitive motor unit action potentials of peripheral origin. It develops as a result of both acquired or hereditary diseases. The acquired form is more frequent and is usually caused by antibodies against neuromuscular junction.

  • Scleroderma is a chronic disease characterized by excessive deposits of collagen. Progressive systemic scleroderma, the serious type of the disease, can be fatal. The local type of the disease is not serious.

  • Vitiligo is the spontaneous loss of pigment from areas of skin. The pigment-free areas have few or no melanocytes. Researchers have detected anti-melanocyte antibodies in some cases of vitiligo, so it seems likely that at least some instances of this condition are the result of autoimmune problems.

  • Vulvodynia is used to describe pain in the vulva, often severe, of unknown cause. "Vulvar vestibulitis" is a related term.


Toxins are substances that cause either permanent or reversible injury to the health of a living thing on contact or absorption, typically by interacting with biological macromolecules such as enzymes and receptors. The term is usually reserved for naturally produced substances that kill rapidly in small quantities, such as the bacterial proteins that cause tetanus and botulism. The word "toxic" is used more loosely and often applied to non-biological materials, as in "toxic waste" and "toxicology."

Ingestable toxins are also often referred to as poisons, especially when intentionally administered by a human. Animal toxins that are delivered subcutaneously (e.g. by sting or bite) are also called venom. (In normal usage, a poisonous organism is one that is harmful to consume, but a venomous organism uses poison to defend itself while still alive. A single organism can be both.)

In most cases the quantity of material is related to its toxicity. Even a material such as water. which is normally considered non-toxic, can be toxic when ingested in sufficient quantity.

Toxicity is measured in terms of the amount of the particular material that is needed to kill half the organisms in the test, which is called the LD50 (Lethal dose for 50%).

Some trace minerals are actually nutrients for plants, animals, or humans at minute levels, but become toxic when the quantity is larger.

Many plants, animals and microorganisms generate toxins to discourage or kill predators. Food poisoning is a term for a broad range of illnesses that can result from eating food that is spoiled or tainted by bacterial toxins, such as botulinum and the so-called Shiga-like toxin secreted by the emergent E. coli strain E. coli O157:H7.

Naturally occurring or human-modified toxins may be intentionally released by humans in chemical warfare.

To see a list of biologically injurious substances, including toxins and other materials, as well as their effects, see poison.


Health Sciences > Medicine > Endocrinology

Endocrinology is a branch of medicine dealing with disorders of the endocrine system and its specific secretions called hormones. Doctors who specialize in treating such disorders are called endocrinologists.

More common endocrinological diseases are :

Neurological disorder

Neurological disorders are a group of disorders that involve the central nervous system (brain, brainstem and cerebellum), the peripheral nervous system (including cranial nerves), and the autonomic nervous system (parts of which are located in both central and peripheral nervous system). Major branches are headache, stupor and coma, dementia, seizure, sleep disorders, trauma, infections, neoplasms, neuroophthalmology, movement disorders, demyelinating diseases, spinal cord disorders, and disorders of peripheral nerves, muscle and neuromuscular junctions.

Many mental illnesses are believed to be neurological disorders of the central nervous system, but they are classified separately. They are not traditionally listed as neurological diseases because their causes are not definitely determined as biological, although there are good reasons to suspect that bipolar disorder and schizophrenia have neuro-chemical causes.

See also: List of neurological disorders

This page created and maintained by Jamie Sanderson.
© Jamie Sanderson 1999-2005.