Thursday, August 6, 2009


van1sh1ng b0n3 Disease

0r Gorham's disease (GD) is an extremely rare bone disorder; 0nly 8 cases are reported in the medical literature sinc3 1883. It is characterized by bone loss (osteolysis) often associated with swelling or abnormal blood vessel growth (angiomatous proliferation). Bone loss can occur in just one bone or spread to soft tissue and adjacent bones.

Although the disease may strike any of the bones of the body, it is more often recognized earlier when the bones at the top of the head (calvarium) and/or the mandibles are involved.

Because of its rarity, the disorder often goes unrecognized. As a result of that, coupled with a lack of agreement on how best to treat Gorham’s disease once it is recognized, treatment may often be delayed. The cause of Gorham’s disease is unknown.

What causes Gorham's disease?

The cause or exact nature of this mysterious disorder remains unknown and it is not usually recognized by clinicians until a fracture occurs, with subsequent improper bone healing. Several theories have been proposed postulating the role of osteoclastic activity. Some studies report that osteoclastosis is not associated with Gorham's disease and that angiomatosis might be the cause. Recently, it has been reported that elevated levels of IL-6 were detected early on in the course of the disease leading to suggest osteoclastic activity. The exact cause of Gorham's disease is controversial to this day. Focused research is needed to determine the exact cause of Gorham's disease.

Who has Gorham's disease?

Gorham's disease is extremely rare and may occur at any age. It has been cited many times that "there are fewer than 200 cases reported in medical literature". It is most often recognized in children and young adults, without gender, race predilection, or inheritance pattern. Because it is so rare, and commonly misdiagnosed, it is not known exactly how many people are affected by this disease.

What are the symptoms of Gorham's disease?

Gorham's disease presents as progressive osteolysis of one bone or contiguous bones around one focus, without respect of anatomical boundaries. It may affect any part of the skeleton, but most commonly involved sites are the skull, mandible, shoulder, rib cage, and pelvis. The degree of complications ranges from mild to severe, even death depending on the site of bony involvement.

During the acute onset, patients may experience localized pain, swelling, or pathological fracture as the disease process occurs. Others however may be asymptomatic. The rate of progression is unpredictable and the prognosis can be difficult. The disease can stabilize after a number of years, go into spontaneous remission, or prove fatal. Recurrence of the disease can also occur. Involvement of the spine and skull base may cause a poor outcome from neurological complications. In many cases, the end result of Gorham's disease is severe deformity and functional disability.

If the disease is present in the ribs, scapula, or thoracic vertebrae, it may lead to the development of chylous pleural and pericardial effusions from the direct extension of the lesion into the pleural cavity or invasion of the thoracic duct. This can have serious consequences, including loss of protein, malnutrition, and respiratory distress and failure.

Xeroderma pigmentosa,

or XP, is an autosomal recessive genetic disorder of DNA repair in which the ability to repair damage caused by ultraviolet (UV) light is deficient.[1]:574 This disorder leads to multiple basal cell carcinomas (basaliomas) and other skin malignancies at a young age. In severe cases, it is necessary to avoid sunlight completely. The two most common causes of death for XP victims are metastatic malignant melanoma and squamous cell carcinoma[2]. XP is about six times more common in Japanese people[2] than in other groups.

The most common defect in xeroderma pigmentosum is an autosomal recessive genetic defect whereby nucleotide excision repair (NER) enzymes are mutated, leading to a reduction in or elimination of NER.[3] Unrepaired damage can lead to mutations, altering the information of the DNA in individual cells. If mutations affect important genes, such as tumour suppressor genes (e.g. p53) or proto oncogenes, then this disorder may lead to cancer. Patients exhibit elevated risk of developing cancer, such as basal cell carcinoma.

Normally, damage to DNA in epidermal cells occurs during exposure to UV light. The absorption of the high energy light leads to the formation of pyrimidine dimers, namely CPDs (cyclobutane-pyrimidine-dimers) and 6-4PPs (pyrimidine-6-4-pyrimidone photoproducts). The normal repair process entails nucleotide excision. The damage is excised by endonucleases, then the gap is filled by a DNA polymerase and "sealed" by a ligase.


Some of the most common symptoms of XP include:

  • An unusually severe sunburn after a short sun exposure. The sunburn may last for several weeks. The sunburn usually occurs during a child's first sun exposure.
  • Development of many freckles at an early age
  • Irregular dark spots on the skin
  • Thin skin
  • Excessive dryness of skin
  • Rough-surfaced growths (solar keratoses), and skin cancers
  • Eyes that are painfully sensitive to the sun and may easily become irritated, bloodshot, and clouded
  • Blistering or freckling on minimum sun exposure
  • Premature aging of skin, lips, eyes, mouth and tongue
  • Crusting skin
  • Spidery blood vessels
  • Scaly skin
  • Oozing raw skin surface
  • Limited growth of hair on chest and legs
Spinocerebellar degeneration disease


Spinocerebellar ataxia (SCA) is one of a group of genetic disorders characterized by slowly progressive incoordination of gait and often associated with poor coordination of hands, speech, and eye movements. Frequently, atrophy of the cerebellum occurs, and different ataxias are known to affect different regions within the cerebellum. [2]

As with other forms of ataxia, SCA results in unsteady and clumsy motion of the body due to a failure of the fine coordination of muscle movements, along with other symptoms.

The symptoms of an ataxia vary with the specific type and with the individual patient. Generally, a person with ataxia retains full mental capacity but may progressively lose physical control.

Treatment and prognosis

There is no known cure for spinocerebellar ataxia, which is a progressive disease (it gets worse with time), although not all types cause equally severe disability.

Treatments are generally limited to softening symptoms, not the disease itself. The condition can be irreversible. A person with this disease will usually end up needing to use a wheelchair, and eventually they may need assistance to perform daily tasks.

The treatment of incoordination or ataxia, then mostly involves the use of adaptive devices to allow the ataxic individual to maintain as much independence as possible. Such devices may include a cane, crutches, walker, or wheelchair for those with impaired gait; devices to assist with writing, feeding, and self care if hand and arm coordination are impaired; and communication devices for those with impaired speech.

Many patients with hereditary or idiopathic forms of ataxia have other symptoms in addition to ataxia. Medications or other therapies might be appropriate for some of these symptoms, which could include tremor, stiffness, depression, spasticity, and sleep disorders, among others.

Both onset of initial symptoms and duration of disease can be subject to variation. If the disease is caused by a polyglutamine trinucleotide repeat CAG expansion, a longer expansion may lead to an earlier onset and a more radical progression of clinical symptoms.

The following is a list of some, not all, types of Spinocerebellar ataxia. The first ataxia gene was identified in 1993 for a dominantly inherited type. It was called “Spinocerebellar ataxia type 1" (SCA1). Subsequently, as additional dominant genes were found they were called SCA2, SCA3, etc. Usually, the "type" number of "SCA" refers to the order in which the gene was found. At this time, there are at least 29 different gene mutations which have been found (not all listed).

Many SCAs below fall under the category of polyglutamine diseases, which are caused when a disease-associated protein (ie. ataxin-1, ataxin-3, etc.) contains a glutamine repeat beyond a certain threshold. In most dominant polyglutamine diseases, the glutamine repeat threshold is approximately 35, except for SCA3 which is beyond 50. Polyglutamine diseases are also known as "CAG Triplet Repeat Disorders" because CAG is the codon which codes for the amino acid glutamine. Many prefer to refer to these also as polyQ diseases since "Q" is the one-letter reference for glutamine.


(US: /ˌvaɪdlˈaɪgoʊ/, /ˌvɪdlˈaɪgoʊ; -ˈigoʊ/, UK: /ˌvɪtɪˈlʌɪgəʊ/) is a chronic disorder that causes depigmentation in patches of skin. It occurs when the melanocytes, the cells responsible for skin pigmentation which are derived from the neural crest, die or are unable to function. The precise pathogenesis, or cause, of vitiligo is complex and not yet fully understood. There is some evidence suggesting it is caused by a combination of autoimmune, genetic, and environmental factors. It is also common in people with thyroid disorders. The population incidence worldwide is considered to be less than 1 percent.[1] Non-segmental vitiligo has a greater prevalence than the disorder's other form(s).

Signs and symptoms

The most notable symptom of vitiligo is depigmentation of patches of skin that occurs on the extremities. Although patches are initially small, they often enlarge and change shape. When skin lesions occur, they are most prominent on the face, hands and wrists. Depigmentation is particularly noticeable around body orifices, such as the mouth, eyes, nostrils, genitalia and umbilicus. Some lesions have hyperpigmentation around the edges. Vitiligo is similar in appearance to leprosy, and as such (in countries where leprosy is prevalent), individuals with vitiligo can be stigmatized for the similarities in appearance.[2] In regards to psychological damage, vitiligo can have a significant effect on the mental health of a patient.[3] Psychological stress may even result in an individual becoming more susceptible to vitiligo. Patients who are stigmatised for their condition may experience depression and similar mood disorders.[4]


Acquired immune deficiency syndrome or acquired immunodeficiency syndrome (AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV).[1][2][3]

This condition progressively reduces the effectiveness of the immune system and leaves individuals susceptible to opportunistic infections and tumors. HIV is transmitted through direct contact of a mucous membrane or the bloodstream with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid, and breast milk.[4][5]

This transmission can involve anal, vaginal or oral sex, blood transfusion, contaminated hypodermic needles, exchange between mother and baby during pregnancy, childbirth, breastfeeding or other exposure to one of the above bodily fluids.

AIDS is now a pandemic.[6] In 2007, it was estimated that 33.2 million people lived with the disease worldwide, and that AIDS had killed an estimated 2.1 million people, including 330,000 children.[7] Over three-quarters of these deaths occurred in sub-Saharan Africa,[7] retarding economic growth and destroying human capital.[8]

Genetic research indicates that HIV originated in west-central Africa during the late nineteenth or early twentieth century.[9][10] AIDS was first recognized by the U.S. Centers for Disease Control and Prevention in 1981 and its cause, HIV, identified in the early 1980s.[11]

Although treatments for AIDS and HIV can slow the course of the disease, there is currently no vaccine or cure. Antiretroviral treatment reduces both the mortality and the morbidity of HIV infection, but these drugs are expensive and routine access to antiretroviral medication is not available in all countries.[12] Due to the difficulty in treating HIV infection, preventing infection is a key aim in controlling the AIDS pandemic, with health organizations promoting safe sex and needle-exchange programmes in attempts to slow the spread of the virus.


A generalized graph of the relationship between HIV copies (viral load) and CD4 counts over the average course of untreated HIV infection; any particular individual's disease course may vary considerably. CD4+ T Lymphocyte count (cells/mm³) HIV RNA copies per mL of plasma

The symptoms of AIDS are primarily the result of conditions that do not normally develop in individuals with healthy immune systems. Most of these conditions are infections caused by bacteria, viruses, fungi and parasites that are normally controlled by the elements of the immune system that HIV damages.

Opportunistic infections are common in people with AIDS.[13] HIV affects nearly every organ system.

People with AIDS also have an increased risk of developing various cancers such as Kaposi's sarcoma, cervical cancer and cancers of the immune system known as lymphomas. Additionally, people with AIDS often have systemic symptoms of infection like fevers, sweats (particularly at night), swollen glands, chills, weakness, and weight loss.[14][15] The specific opportunistic infections that AIDS patients develop depend in part on the prevalence of these infections in the geographic area in which the patient lives.


Scanning electron micrograph of HIV-1, colored green, budding from a cultured lymphocyte.

AIDS is the most severe acceleration of infection with HIV. HIV is a retrovirus that primarily infects vital organs of the human immune system such as CD4+ T cells (a subset of T cells), macrophages and dendritic cells. It directly and indirectly destroys CD4+ T cells.[34]

Once HIV has killed so many CD4+ T cells that there are fewer than 200 of these cells per microliter (µL) of blood, cellular immunity is lost. Acute HIV infection progresses over time to clinical latent HIV infection and then to early symptomatic HIV infection and later to AIDS, which is identified either on the basis of the amount of CD4+ T cells remaining in the blood, and/or the presence of certain infections, as noted above.[35]

In the absence of antiretroviral therapy, the median time of progression from HIV infection to AIDS is nine to ten years, and the median survival time after developing AIDS is only 9.2 months.[36] However, the rate of clinical disease progression varies widely between individuals, from two weeks up to 20 years.

Many factors affect the rate of progression. These include factors that influence the body's ability to defend against HIV such as the infected person's general immune function.[37][38] Older people have weaker immune systems, and therefore have a greater risk of rapid disease progression than younger people.

Poor access to health care and the existence of coexisting infections such as tuberculosis also may predispose people to faster disease progression.[36][39][40] The infected person's genetic inheritance plays an important role and some people are resistant to certain strains of HIV. An example of this is people with the homozygous CCR5-Δ32 variation are resistant to infection with certain strains of HIV.[41] HIV is genetically variable and exists as different strains, which cause different rates of clinical disease progression.[42][43][44]

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