Alopecia universalis (AU) is the most clinically debilitating manifestation of alopecia areata, an inflammatory disease of hair follicle. AU is distinguished from other forms of alopecia areata by a total loss of hair of the scalp and other parts of the body where hair normally grows.
The characteristic appearance of an alopecic scalp is a smooth, pinkish or normal colored area or plaque, with or without exclamation point hairs. The ease with which hair is plucked from the outer border of the plaque, as it were in other hair-bearing parts of the body, indicates an active disease condition and that progressive hair loss is imminent. The presence of one or several roundish denuded patches is common, without concomitant epidermal changes. Alopecia areata, is usually focal or may be diffused, mimicking telogen effluvium (TE) or female-pattern androgenetic alopecia.
Extensive hair loss and coalescing patches result in a reticular appearance. Bald areas located at the sides and back of the head make up the so-called ophiasis pattern or the opposite, sisaipho pattern when affected areas do not involve the sides and back of the head.
Dermoscopy, as simple and safe as it, is a recent development in the evaluation of hair loss. However, further study is needed in order to validate its reliability as a diagnostic tool . Yellow dots, a diagnostic feature of alopecia areata, have been reported in 95% of patients at various stages of the disease. These yellow dots are actually degenerated follicular keratinocytes and sebum contained within the ostium of hair follicles, seen in advanced male-pattern hair loss, but not in female-pattern hair loss, telogen effluvium and scarring alopecia. Other dermoscopic signs to aid diagnosis include presence of black dots, clustered short vellus hairs, broken hairs, and tapering hairs.
Male-pattern or female-pattern hair loss is readily diagnosed. Alopecia in young men with no family history of the disorder may be the result of the use of anabolic steroids and other drugs, with or without proper prescription. Hair loss in women with evidence of virilization may be accompanied by significant levels of testosterone or dehydroepiandrosterone sulfate.
Diffuse scalp hair loss may be subjected to the pull or pluck test. A group of 40 hair shafts (with the follicles or roots) each from 3 separate patches is pulled away gently. The number of hair shafts that are detached from the scalp are counted and the roots are examined under the microscope. Less than 3 telogen-phase hairs is normal, more than 4 to 6 per batch is positive and indicative of telogen effluvium.
The roots when examined microscopically can indicate the phase of growth and identify telogen or anagen defect or an occult pathological condition. Whereas anagen hairs have sheaths attached to their roots, telogen hairs have only tiny bulbs (not sheaths) at their roots. Normal hair consists of 85 to 90% in the anagen phase, about 10 to 15% in telogen phase, and < 1% are in catagen phase. Telogen effluvium is characterized by more that 20% telogen-phase hairs; whereas anagen effluvium is identified by a decrease in telogen-phase hairs and an increased number of broken hairs. Primary hair shaft abnormalities are readily detected by routine microscopy.
Scalp biopsy is appropriate for persistent and dubious cases of alopecia to differentiate scarring from nonscarring forms. Samples are taken from areas of active inflammation, usually the border of a bald patch where hair detaches easily. Cultures for fungal and bacterial pathogens are likewise recommended.
The patient can be instructed to monitor hair loss by daily hair counts each morning after combing or during washing. Hair is kept in clear plastic bags for 14 days and brought to the laboratory for microscopy. Scalp hair counts of > 100/day before shampooing are abnormal and 250 with shampooing is normal.
Cortisone: Oral cortisone is considered more effective than injection for the treatment of extensive alopecia although care must be taken to avoid the side effects of prolonged use. Healthy young persons can usually take cortisone with less adverse consequences. Regrown hair is liable to degenerate when cortisone is withdrawn.
Topical immunotherapy: This involves applying certain chemicals on the scalp to induce an allergic rash or allergic contact dermatitis on the scalp . Diphencyprone (DPCP), dinitrochlorobenzene (DNCB) or squaric acid dibutyl ester (SADBE) produces an allergic reaction resembling that caused by poison ivy or oak. It has been shown that about 40% of patients experienced hair regrowth after six months of treatment. Others may need to continue the treatment to maintain hair regrowth. One drawback is prurigo during hot weather if the patient is wearing a wig. This is practiced in Canada and Europe but not in the United States.
Wigs: These are more appropriate in extensive alopecia (AT and AU) . Quality wig should be designed for comfort and esthetic reasons. For completely bare heads, suction caps and silicon base are installed to ensure good fit. The cost of these custom-built accessories is a consideration for the patient.
The clinical course of alopecia areata leaves much to be understood in terms of affected persons, causes pathogenesis and the role of predisposing factors. Majority of cases are limited to a few focal areas of hair loss, with spontaneous regrowth in less than a year. Less than 10% of patients have extensive alopecia and less than 1% have alopecia universalis, the least common but advanced type of alopecia.
Extensive long-standing cases of alopecia may not be able to experience long-lasting regrowth. Occurrence of atopy, nail abnormalities, early onset of the disorder, and severe forms of alopecia areata presage poor prognosis.
The etiology of alopecia universalis remains to be confirmed. It is presumed to be an autoimmune disease in which T lymphocytes are involved in a pathogenic process directed at hair follicles . There is evidence that both innate and adaptive immunity participate in this process. Likewise, genetics and environment may have a role in terms of susceptibility to and severity of the disorder .
Alopecia consists of various forms and manner of causation. The most common cause of alopecia is androgenic alopecia (male-pattern or female-pattern hair loss). This is hereditary and dihydrotestosterone-dependent. Eighty percent (80%) of white men in their 70s and 50% of all women are affected.
In summary, hair loss may be due to:
The over-all prevalence of alopecia universalis is 1-5:10 000 population .
The pathophysiological basis of alopecia areata is probably congruent in all types, but remains to be fully understood. There is, however, consensus on a direct effect on hair follicles by T-cell mediated autoimmune process with the participation of genetic and environmental factors .
There is likewise evidence that mediators of both innate and adaptive immunity are involved. Anti-hair follicle antibodies have been found in alopecia areata patients compared with the control group. Antibodies to anagen-phase hair follicles were found in 90% alopecia patients versus 37% of non-alopecia peers. The autoantibody is heterologous, attacking various structures of the hair follicle, in decreasing frequency, namely - the outer root sheath, the inner root sheath, the matrix, and the hair shaft. The exact nature of this phenomenon is not known.
Biopsy showed a perifollicular lymphocytic infiltrate surrounding hair follicles, consisting of T-helper cells and T-suppressor cells. In Dundee experimental bald rat (DEBR) model of alopecia areata, reduction of CD4+ and CD8+ cell counts was linked to complete or partial regrowth of hair. Conversely, hair loss occurred when the T-cell population was replenished. Other mechanisms may be involved in experimental animals that did not show complete regrowth. In this study, total counts of circulating T lymphocytes were monitored.
Nude (congenitally athymic) mice did not experience hair loss when serum from affected patients was injected IV into regrown patches of alopecia. The same study showed that mice injected with alopecia areata serum exhibited increased deposition of immunoglobulin and complement in hair follicles of both grafted and nongrafted skin; none was seen in mice injected with control serum. Alopecia has been induced in normal recipients of skin grafts from alopecia areata–affected mice. On the other hand, grafts from normal mice exhibited hair loss when transferred to alopecia mice.
The foregoing observations substantiate the role of immunologic factors in hair loss and/or growth in alopecia areata. A possible melanocytic target within the hair follicle is suggested.
Data indicate that there is a genetic predisposition for alopecia areata. It has been estimated that 10-20% of alopecia patients had a positive family history of the disorder versus 1.7% in the control group. Patients with fulminant disease comprised 16-18% of all cases compared with 7-13% of those with localized lesions. Alopecia areata has been reported in twins. Correlation between severity and type of alopecia among relatives has not been established. Human leukocyte antigen DQ3 (DQB1*03) was found in more than 80% of patients with alopecia areata, suggesting this to be a possible marker for susceptibility to alopecia. Furthermore, human leukocyte antigen DQ7 (DQB1*0301) and human leukocyte antigen DR4 (DRB1*0401) are being linked to patients with alopecia totalis and alopecia universalis .
Interleukin 1 receptor antagonist gene may be associated with severity of disease. The occurrence of alopecia areata in Down syndrome suggests a probable genetic predisposition involving chromosome 21.
Cultured hair follicles were treated in vitro with interleukin 1 (IL-1) and tumor necrosis factor (TNF). The results showed inhibition of hair growth and morphologic changes as seen by microscopy in clinical cases of alopecia areata.
Innervation and vasculature
Modification of perifollicular nerves is a case in point. The peripheral nervous system is probably involved when alopecia patients experience itching or pain on affected areas. The neuropeptide calcitonin gene-related peptide (CGRP) was shown to decrease in the circulation in 3 alopecia patients versus control. CGRP is known to have various functions in the immune system, such as chemotaxis, inhibition of mitogen-stimulated T-lymphocyte proliferation, and inhibition of Langerhans cell antigen presentation.
CGRP likewise increases endothelial proliferation and vasodilatation. Another study reported significant decrease in cutaneous levels of substance P and of CGRP in scalp biopsy specimens. Intradermal injection of CGRP in alopecia patients lowered basal blood flow and increased vasodilatation. More studies are needed to determine the implication of these observations in the pathogenesis of alopecia areata.
One can only anticipate but can not prevent the occurrence of alopecia. There are a multitude of factors that may predispose a person to the disorder. First consideration is to seek counselling from a knowledgeable health professional, then a specialist if signs and symptoms are evident.
Every case needs to be evaluated clinically and verified by available laboratory examinations. Several treatment modalities are presently available.
Alopecia universalis (AU) is the most severe form of alopecia areata, an autoimmune, inflammatory disorder of hair follicles resulting in loss of hair on the scalp and other hair-bearing parts of the body. Alopecia areata can be classified according to the pattern of hair loss:
The hair follicles remain viable in alopecia areata. In all cases, hair regrowth may occur with or without treatment for years.
Alopecia universalis (AU) is one of types of alopecia areata or hair loss. AU is the most severe type, characterized by the complete loss of hair on the scalp and other hair-bearing parts of the body. Most AU-affected persons do not experience any other signs and symptoms, except for a burning sensation or itchiness on affected areas, if at all.
The precise cause of alopecia universalis remains to be fully understood. Alopecia areata in general is presumed to be an autoimmune disorder in which the body's own immune system attacks hair follicles. Studies have shown that components of both innate and adaptive immunity are involved with the participation of genetic and environmental factors. A person may inherit the genetic predisposition to the condition, but may not develop the disorder unless triggered by some environmental stimuli.
Diagnosis of AU can be established on the basis of thorough physical and clinical evaluation. Sometimes a scalp biopsy may be needed to confirm the diagnosis.
Treatment of AU is limited to the use of oral corticosteroids to induce hair regrowth and topical applications on the scalp to relieve prurigo, at the discretion of a physician. Risk of side effects from prolonged use of steroids should be considered. About 40% of patients may experience regrowth within six months; others may have to continue for longer periods. Sometimes the hair will degenerate and fall out when the steroid is withdrawn.