| Alopecia universalis | |
|---|---|
 | |
| Former association football referee Pierluigi Collina with alopecia universalis. | |
| Specialty | Dermatology  |
Alopecia universalis(AU), also known as alopecia areata universalis, is a medical condition involving the loss of all body hair, including eyebrows, eyelashes, chest hair, armpit hair, and pubic hair. It is the most severe form of alopecia areata (AA). [1] People with the condition are usually healthy and have no other symptoms and a normal life expectancy. [2]
Alopecia universalis can occur at any age, and is currently believed to be an autoimmune disorder, in which a person's immune system attacks the hair follicles. Genetic factors may contribute to AU, as about 20% of those affected have a family member with alopecia. [3]
Many treatments have been explored, including immunomodulatory agents such as imiquimod. [4] Tofacitinib citrate may also have benefits. In June 2014, a 25-year-old man with almost no hair on his body was reported to have grown a full head of hair, as well as eyebrows, eyelashes, and facial, armpit, and other hair, following eight months of treatment. [5]
Contact immunotherapy involves the use of contact allergens, such as diphencyprone and squaric acid dibutylester, to induce an immune response that is thought to oppose the action of cells causing hair loss. [6] [7] [8] A review that combined and analyzed the findings of 45 studies comprising 2,227 patients showed any hair regrowth in 54.5% and complete hair regrowth in 24.9% of patients with AT and AU using contact immunotherapy. [9] In addition to its helpful effects in treating AU, it can have side effects that can be very serious, such as severe dermatitis. [6] [10]
Topical and intralesional corticosteroids, such as clobetasol propionate, have also shown to be an effective treatment for AT and AU patients. [6] [7] A controlled study comprising 28 patients found positive terminal hair growth in eight of the patients (28.5%) using a 0.05% clobetasol propionate ointment. [11] This is very similar to the results obtained from immunotherapy treatment trials. Additionally, studies suggest that intralesional applications are much more effective than topical applications of steroids. However, the main side effect is increased risk of cutaneous atrophy at the site of treatment; [7] folliculitis is also an occasional complication. [8]
Janus kinase inhibitors, previously used in the treatment of cancer and other diseases, such as arthritis, have successfully shown to be effective in the initial trials of treatment for alopecia patients. [6] [7] [12] Multiple cases of treatments have been successful, one of them being of a 22-year-old man with a history of AU and atopic dermatitis (AD). This man was treated with JAK inhibitor tofacitinib, and after ten months, he experienced hair regrowth on all of his affected body parts and subsequent improvement of his AD. [13] [14] Current research and findings suggest that systemic JAK inhibitors eliminate and prevent the development of AA, while topical JAK inhibitors promote hair regrowth and reverse the established disease. [8] [15] Many clinical trials are ongoing involving JAK inhibitors such as ruxolitinib and tofacitinib. [6] [16]
Janus kinase (JAK) is a family of intracellular, non-receptor tyrosine kinases that transduce cytokine-mediated signals via the JAK-STAT pathway. They were initially named "just another kinase" 1 and 2, but were ultimately published as "Janus kinase". The name is taken from the two-faced Roman god of beginnings, endings and duality, Janus, because the JAKs possess two near-identical phosphate-transferring domains. One domain exhibits the kinase activity, while the other negatively regulates the kinase activity of the first.
Alopecia areata, also known as spot baldness, is a condition in which hair is lost from some or all areas of the body. It often results in a few bald spots on the scalp, each about the size of a coin. Psychological stress and illness are possible factors in bringing on alopecia areata in individuals at risk, but in most cases there is no obvious trigger. People are generally otherwise healthy. In a few cases, all the hair on the scalp is lost, or all body hair is lost. Hair loss can be permanent, or temporary.
Hair loss, also known as alopecia or baldness, refers to a loss of hair from part of the head or body. Typically at least the head is involved. The severity of hair loss can vary from a small area to the entire body. Inflammation or scarring is not usually present. Hair loss in some people causes psychological distress.
Clobetasol propionate is a corticosteroid used to treat skin conditions such as eczema, contact dermatitis, seborrheic dermatitis, steroid responsive dermatosis, and psoriasis.
Telogen effluvium is a scalp disorder characterized by the thinning or shedding of hair resulting from the early entry of hair in the telogen phase. It is in this phase that telogen hairs begin to shed at an increased rate, where normally the approximate rate of hair loss is 125 hairs per day.
The management of hair loss, includes prevention and treatment of alopecia, baldness, and hair thinning, and regrowth of hair.
Alopecia totalis is the loss of all hair on the head and face. Its causes are unclear, but believed to be autoimmune. Research suggests there may be a genetic component linked to developing alopecia totalis; the presence of DRB1*0401 and DQB1*0301, both of which are human leukocyte antigens (HLA), were found to be associated with long-standing alopecia totalis.
Ophiasis is a form of alopecia areata characterized by the loss of hair in the shape of a wave at the circumference of the head.
Madarosis is a condition that results in the loss of eyelashes, and sometimes eyebrows. The term "madarosis" is derived from the ancient Greek "madaros", meaning "bald". It originally was a disease of only losing eyelashes but it currently is the loss of both eyelashes and eyebrows. Eyebrows and eyelashes are both important in the prevention of bacteria and other foreign objects from entering the eye. A majority of patients with madarosis have leprosy, and it was reported that 76% of patients with varying types of leprosy had madarosis.
Non scarring hair loss, also known as noncicatricial alopecia is the loss of hair without any scarring being present. There is typically little inflammation and irritation, but hair loss is significant. This is in contrast to scarring hair loss during which hair follicles are replaced with scar tissue as a result of inflammation. Hair loss may be spread throughout the scalp (diffuse) or at certain spots (focal). The loss may be sudden or gradual with accompanying stress.
Antonella Tosti is an Italian physician and scientist with major contributions in the field of dermatology, including developing dermoscopy for the diagnosis and care of hair diseases, a world recognized expert in hair disorders. Her contributions to knowledge about nails include research about videodermoscopy of the hyponychium and the nail plate.
A Janus kinase inhibitor, also known as JAK inhibitor or jakinib, is a type of immune modulating medication, which inhibits the activity of one or more of the Janus kinase family of enzymes, thereby interfering with the JAK-STAT signaling pathway in lymphocytes.
The growth of human hair occurs everywhere on the body except for the soles of the feet, the palms of the hands, the inside of the mouth, the lips, the backs of the ears, some external genital areas, the navel, and, apart from eyelashes, the eyelids. Hair is a stratified squamous keratinized epithelium made of multi-layered flat cells whose rope-like filaments provide structure and strength to the hair shaft. The protein called keratin makes up hair and stimulates hair growth. Hair follows a specific growth cycle with three distinct and concurrent phases: anagen, catagen, and telogen. Each phase has specific characteristics that determine the length of the hair.
Tofacitinib, sold under the brand Xeljanz among others, is a medication used to treat rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, polyarticular course juvenile idiopathic arthritis, and ulcerative colitis. It is a janus kinase (JAK) inhibitor, discovered and developed by the National Institutes of Health and Pfizer.
Diphenylcyclopropenone (diphencyprone) is a topically administered experimental drug intended for treating alopecia areata and alopecia totalis. Topical immunotherapy using diphenylcyclopropenone may also be an effective treatment option for recalcitrant warts. It is not approved by either the Food and Drug Administration or the European Medicines Agency.
Baricitinib, sold under the brand name Olumiant among others, is an immunomodulatory medication used for the treatment of rheumatoid arthritis, alopecia areata, and COVID-19. It acts as an inhibitor of janus kinase (JAK), blocking the subtypes JAK1 and JAK2.
In the field of dermatology, the Renbök phenomenon is a phenomenon where one skin condition inhibits another. It is also known as the reverse Koebner phenomenon. The term was first used by Happle et al. in 1991. The word "Renbök" is a neologism, made from a reversal of the letters of the name "Köbner".
Janus kinase 3 inhibitors, also called JAK3 inhibitors, are a new class of immunomodulatory agents that inhibit Janus kinase 3. They are used for the treatment of autoimmune diseases. The Janus kinases are a family of four nonreceptor tyrosine-protein kinases, JAK1, JAK2, JAK3, and TYK2. They signal via the JAK/STAT pathway, which is important in regulating the immune system. Expression of JAK3 is largely restricted to lymphocytes, while the others are ubiquitously expressed, so selective targeting of JAK3 over the other JAK isozymes is attractive as a possible treatment of autoimmune diseases.
Frictional alopecia is the loss of hair that is caused by rubbing of the hair, follicles, or skin around the follicle. The most typical example of this is the loss of ankle hair among people who wear socks constantly for years. The hair may not grow back even years after the source of friction has ended.
Angela M. Christiano is a molecular geneticist in the field of dermatology. Her research focuses on genes involved in hair and skin growth, as well as treatments for hair loss and skin cancers. She is the Richard and Mildred Rhodebeck Professor of Dermatology and Professor of Genetics and Development at Columbia University Vagelos College of Physicians and Surgeons.