Antibodies to hair follicles in alopecia areata

Deciphering the Complex Immunopathogenesis of Alopecia Areata

Alopecia areata (AA) is an autoimmune-mediated disorder in which the proximal hair follicle (HF) attack results in non-scarring partial to total scalp or body hair loss. Despite the growing knowledge about AA, its exact cause still needs to be understood. However, immunity and genetic factors are affirmed to be critical in AA development. While the genome-wide association studies proved the innate and acquired immunity involvement, AA mouse models implicated the IFN-γ- and cytotoxic CD8+ T-cell-mediated immune response as the main drivers of disease pathogenesis. The AA hair loss is caused by T-cell-mediated inflammation in the HF area, disturbing its function and disrupting the hair growth cycle without destroying the follicle. Thus, the loss of HF immune privilege, autoimmune HF destruction mediated by cytotoxic mechanisms, and the upregulation of inflammatory pathways play a crucial role. AA is associated with concurrent systemic and autoimmune disorders such as atopic dermatitis, vitiligo, psoriasis, and thyroiditis. Likewise, the patient's quality of life (QoL) is significantly impaired by morphologic disfigurement caused by the illness. The patients experience a negative impact on psychological well-being and self-esteem and may be more likely to suffer from psychiatric comorbidities. This manuscript aims to present the latest knowledge on the pathogenesis of AA, which involves genetic, epigenetic, immunological, and environmental factors, with a particular emphasis on immunopathogenesis.

Inhibition of T-cell activity in alopecia areata: recent developments and new directions

Alopecia areata (AA) is an autoimmune disease that has a complex underlying immunopathogenesis characterized by nonscarring hair loss ranging from small bald patches to complete loss of scalp, face, and/or body hair. Although the etiopathogenesis of AA has not yet been fully characterized, immune privilege collapse at the hair follicle (HF) followed by T-cell receptor recognition of exposed HF autoantigens by autoreactive cytotoxic CD8+ T cells is now understood to play a central role. Few treatment options are available, with the Janus kinase (JAK) 1/2 inhibitor baricitinib (2022) and the selective JAK3/tyrosine kinase expressed in hepatocellular carcinoma (TEC) inhibitor ritlecitinib (2023) being the only US Food and Drug Administration-approved systemic medications thus far for severe AA. Several other treatments are used off-label with limited efficacy and/or suboptimal safety and tolerability. With an increased understanding of the T-cell-mediated autoimmune and inflammatory pathogenesis of AA, additional therapeutic pathways beyond JAK inhibition are currently under investigation for the development of AA therapies. This narrative review presents a detailed overview about the role of T cells and T-cell-signaling pathways in the pathogenesis of AA, with a focus on those pathways targeted by drugs in clinical development for the treatment of AA. A detailed summary of new drugs targeting these pathways with expert commentary on future directions for AA drug development and the importance of targeting multiple T-cell-signaling pathways is also provided in this review.

Clinical characteristics and immune profiles of patients with immune-mediated alopecia associated with COVID-19 vaccinations

BACKGROUND

The clinical characteristics and pathomechanism for immune-mediated alopecia following COVID-19 vaccinations are not clearly characterized.

OBJECTIVE

We investigated the causality and immune mechanism of COVID-19 vaccines-related alopecia areata (AA).

STUDY DESIGN

27 new-onset of AA patients after COVID-19 vaccinations and 106 vaccines-tolerant individuals were enrolled from multiple medical centers for analysis.

RESULTS

The antinuclear antibody, total IgE, granulysin, and PARC/CCL18 as well as peripheral eosinophil count were significantly elevated in the patients with COVID-19 vaccines-related AA compared with those in the tolerant individuals (P = 2.03 × 10-5-0.039). In vitro lymphocyte activation test revealed that granulysin, granzyme B, and IFN-γ released from the T cells of COVID-19 vaccines-related AA patients could be significantly increased by COVID-19 vaccine excipients (polyethylene glycol 2000 and polysorbate 80) or spike protein (P = 0.002-0.04).

CONCLUSIONS

Spike protein and excipients of COVID-19 vaccines could trigger T cell-mediated cytotoxicity, which contributes to the pathogenesis of immune-mediated alopecia associated with COVID-19 vaccines.

Dermatologic manifestations of thyroid disease: a literature review

Introduction

Thyroid hormone is considered one of the key regulatory hormones for skin homeostasis. Multiple organs are affected by the release of peripheral thyroid hormones (T4 and T3) further regulating various functions at a cellular level. Specifically, skin is considered an important target organ in which the thyroid hormone has a significant impact. Multiple skin diseases are associated with thyroid hormone dysregulation. However, other striking dermatologic manifestations are seen in nails and hair as well. Hypothyroidism, hyperthyroidism, and thyroid cancer can have an array of cutaneous manifestations, and we present the recent updates in this field.

Methods

A PubMed search was performed for updates in any new skin disease findings and treatments between 2010 and 2022. Research published in the past decade and previously known foundational skin findings associated with thyroid disease were presented in this review.

Conclusion

Cutaneous manifestations of thyroid disease is one of the first notable signs of thyroid hormone dysregulation. This article reviews the recent updates on the thyroid and skin interplay, and it further discusses overt visible findings and various available treatment modalities.

Stratification of alopecia areata reveals involvement of CD4 T cell populations and altered faecal microbiota

Alopecia areata (AA) is an immune-mediated disease that causes non-scarring hair loss. Autoreactive CD8 T cells are key pathogenic effectors in the skin, and AA has been associated both with atopy and with perturbations in intestinal homeostasis. This study aimed to investigate mechanisms driving AA by characterizing the circulating immunophenotype and faecal microbiome, and by stratifying AA to understand how identified signatures associated with heterogeneous clinical features of the condition. Flow cytometric analyses identified alterations in circulating B cells and CD4 T cells, while 16S sequencing identified changes in alpha and beta diversity in the faecal microbiome in AA. The proportions of transitional and naïve B cells were found to be elevated in AA, particularly in AA samples from individuals with >50% hair loss and those with comorbid atopy, which is commonly associated with extensive hair loss. Although significant changes in circulating CD8 T cells were not observed, we found significant changes in CD4+ populations. In individuals with <50% hair loss higher frequencies of CCR6+CD4 ("Th17") and CCR6+CXCR3+CD4 ("Th1/17") T cells were found. While microbial species richness was not altered, AA was associated with reduced evenness and Shannon diversity of the intestinal microbiota, again particularly in those with <50% hair loss. We have identified novel immunological and microbial signatures in individuals with alopecia areata. Surprisingly, these are associated with lower levels of hair loss, and may therefore provide a rationale for improved targeting of molecular therapeutics.

Is there a link between alopecia areata and gut?

BACKGROUND

There may be an association between increased intestinal permeability and the progression of alopecia areata (AA).

OBJECTIVE

The present study aimed to investigate the role of intestinal permeability in the etiopathogenesis of AA and its association with the severity of the disease.

METHODS

Serum zonulin levels of 70 patients with AA who were not receiving any systemic treatment and of 70 healthy control subjects were measured.

RESULTS

The median serum zonulin level in the patient group (46.38 ng/mL) did not differ significantly from that in the control group (50.34 ng/mL) (p = 0.828). Moreover, there was no significant relationship between serum zonulin levels and the severity of the disease (p = 0.549).

LIMITATIONS

The present study had a cross-sectional design, and it did not include patients with alopecia totalis (AT) or alopecia universalis (AU).

CONCLUSION

We did not observe an increase in intestinal permeability secondary to zonulin expression in patients with AA. However, in order to generalize this result to all patients with AA, serum zonulin levels need to be evaluated in studies including more patients with severe disease, AT, and AU.

Autoantigen Discovery in the Hair Loss Disorder, Alopecia Areata: Implication of Post-Translational Modifications

Alopecia areata (AA) is a chronic, multifactorial, polygenic, and heterogeneous disorder affecting growing hair follicles in susceptible individuals, which results in a non-scarring and reversible hair loss with a highly unpredictable course. Despite very considerable research effort, the nature of the precipitating factor(s) responsible for initiating AA in any given hair follicle remains unclear, due largely to significant gaps in our knowledge of the precise sequence of the etiopathogenic events in this dermatosis. However, disease-related changes in the immune-competence of the lower growing hair follicle, together with an active immune response (humoral and cellular) to hair follicle-associated antigens, are key associated phenomena. Confirmation of the hair follicle antigen(s) implicated in AA disease onset has remained stubbornly elusive. While it may be considered somewhat philosophical by some, it is also unclear whether immune-mediated hair loss in AA results from a) an ectopic (i.e., in an abnormal location) immune response to native (unmodified) self-antigens expressed by the healthy hair follicle, b) a normal immune response against modified self-antigens (or neoantigens), or c) a normal immune response against self-antigens (modified/non-modified) that were not previously visible to the immune system (because they were conformationally-hidden or sequestered) but become exposed and presentable in an MHC-I/-II molecule-restricted manner. While some candidate hair follicle antigen target(s) in AA are beginning to emerge, with a potential role for trichohyalin, it is not yet clear whether this represents the initial and immunodominant antigenic focus in AA or is simply one of an expanding repertoire of exposed hair follicle tissue damage-associated antigens that are secondary to the disease. Confirmation of autoantigen identity is essential for our understanding of AA etiopathogenesis, and consequently for developing a more informed therapeutic strategy. Major strides have been made in autoantigen discovery in other autoimmune conditions. In particular, some of these conditions may provide insights into how post-translational modifications (e.g., citrullination, deamidation, etc.) of hair follicle-restricted proteins may increase their antigenicity and so help drive the anti-hair follicle immune attack in AA.

Clinical Translation of Microbiome Research in Alopecia Areata: A New Perspective?

The continuous research advances in the microbiome field is changing clinicians’ points of view about the involvement of the microbiome in human health and disease, including autoimmune diseases such as alopecia areata (AA). Both gut and cutaneous dysbiosis have been considered to play roles in alopecia areata. A new approach is currently possible owing also to the use of omic techniques for studying the role of the microbiome in the disease by the deep understanding of microorganisms involved in the dysbiosis as well as of the pathways involved. These findings suggest the possibility to adopt a topical approach using either cosmetics or medical devices, to modulate or control, for example, the growth of overexpressed species using specific bacteriocins or postbiotics or with pH control. This will favour at the same time the growth of beneficial bacteria which, in turn, can impact positively both the structure of the scalp ecosystem on the host’s response to internal and external offenders. This approach, together with a “systemic” one, via oral supplementation, diet, or faecal transplantation, makes a reliable translation of microbiome research in clinical practice and should be taken into consideration every time alopecia areata is considered by a clinician.

Whole exome sequencing in Alopecia Areata identifies rare variants in KRT82

Alopecia areata is a complex genetic disease that results in hair loss due to the autoimmune-mediated attack of the hair follicle. We previously defined a role for both rare and common variants in our earlier GWAS and linkage studies. Here, we identify rare variants contributing to Alopecia Areata using a whole exome sequencing and gene-level burden analyses approach on 849 Alopecia Areata patients compared to 15,640 controls. KRT82 is identified as an Alopecia Areata risk gene with rare damaging variants in 51 heterozygous Alopecia Areata individuals (6.01%), achieving genome-wide significance (p = 2.18E−07). KRT82 encodes a hair-specific type II keratin that is exclusively expressed in the hair shaft cuticle during anagen phase, and its expression is decreased in Alopecia Areata patient skin and hair follicles. Finally, we find that cases with an identified damaging KRT82 variant and reduced KRT82 expression have elevated perifollicular CD8 infiltrates. In this work, we utilize whole exome sequencing to successfully identify a significant Alopecia Areata disease-relevant gene, KRT82, and reveal a proposed mechanism for rare variant predisposition leading to disrupted hair shaft integrity.

Common variants have been discovered to be associated with Alopecia Areata; however, rare variants have been less well studied. Here, the authors use whole-exome sequencing to identify associated rare variants in the hair keratin gene KRT82. Further, they find that individuals with Alopecia Areata have reduced expression of KRT82 in the skin and hair follicle.

The current state of knowledge of the immune ecosystem in alopecia areata

Alopecia areata (AA) is an autoimmune disease that affects approximately 2% of the general population. Patients with AA most commonly present with one or more patches of hair loss on the scalp in defined circular areas. A fraction of patients progress to more severe forms of the disease, in some cases with involvement of all body surfaces. The healthy anagen stage hair follicle is considered an immune privileged site, described as an environment that suppresses inflammatory immune responses. However, in AA, this immune privileged state collapses and marks the hair follicle as a target for the immune system, resulting in peri- and intrafollicular infiltration by lymphocytes. The complexity of the inflammatory ecosystem of the immune response to the hair follicle, and the relationships between the cellular and soluble participants, in AA remains incompletely understood. Many studies have demonstrated the presence of various immune cells around diseased hair follicles; however, often little is known about their respective contributions to AA pathogenesis. Furthering our understanding of the mechanisms of disease in AA is essential for the novel identification of targeted therapeutics that are efficacious and have few unintended effects.

Association between alopecia areata and thyroid dysfunction

Alopecia Areata is an inflammatory and T cell-mediated autoimmune reaction against unknown autoantigen of hair follicles characterized by patchy, non-scarring loss of hair follicles in the anagen phase. Although its etiology is minimally understood, genetic susceptibility, autoimmunity and stress are thought to be causative factors. It occurs in episodic and recurrent patterns with an incidence rate of 0.1-0.2% in the general population and 7-30 cases per 1000 dermatological patients with a lifetime risk of 1.7%. The lesions can be single and self-limiting or may be widespread. Autoimmune disorders such as Hashimoto's thyroiditis, Vitiligo, celiac disease, diabetes mellitus, psoriasis ad lupus erythematosus were observed as an associated comorbid disorder in AA patients, but hypothyroidism and Vitiligo have the strongest association. Its clinical course is unpredictable and shows no significant predilection to age, gender or race. AA is a heterogeneous variant of alopecia and has clinical types such as patchy alopecia, alopecia reticularis and alopecia totalis. Various epidemiological reports demonstrate an increased frequency of AA in thyroid disease patients. Contemporary research has shed spotlight on circulating auto-reactive cells in evolution of AA, which may play a role in ultimately linking these diseases. Comprehension of complex interplay between autoantigens and immune cells is still evolving. The present study will explore this association of Alopecia Areata in patients with thyroid dysfunction. This correlation was studied briefly with literature available in the medical database such as PubMed and Google Scholar.

Immunology of alopecia areata

Alopecia areata is a condition that affects hair follicles and leads to hair loss ranging from small well-defined patches to complete loss of all body hair. Despite its high incidence, the pathobiology is not fully understood, and no single concept could be universally accepted.

Alopecia areata is mostly considered to be an autoimmune disease, in which the collapse of hair follicle immune privilege plays a key role. Higher incidence rate in the female population and increased overall risk of other autoimmune disorders militate in favor of autoimmune hypothesis. Antibodies against multiple components of hair follicles almost exclusively attack in anagen phase, where melanogenesis takes place. It suggests involvement of melanogenesis-associated autoantigens as a target epitope.

Some investigators believed that alopecia areata is not a truly autoimmune disease but is only ‘consistent with’ autoimmune mechanisms. High frequency of a positive family history up to 42% may reflects the contribution of heredity factors. In addition, no specific target autoantigen has been identified so far, and autoantibodies to hair follicle-associated antigens are detectable in normal individuals.

Pathomechanisms of immune-mediated alopecia

The hair follicle (HF) is a complex mini-organ that constantly undergoes dynamic cycles of growth and regression throughout life. While proper progression of the hair cycle requires homeostatic interplay between the HF and its immune microenvironment, specific parts of the HF, such as the bulge throughout the hair cycle and the bulb in the anagen phase, maintain relative immune privilege (IP). When this IP collapses, inflammatory infiltrates that aggregate around the bulge and bulb launch an immune attack on the HF, resulting in hair loss or alopecia. Alopecia areata (AA) and primary cicatricial alopecia (PCA) are two common forms of immune-mediated alopecias, and recent advancements in understanding their disease mechanisms have accelerated the discovery of novel treatments for immune-mediated alopecias, specifically AA. In this review, we highlight the pathomechanisms involved in both AA and CA in hopes that a deeper understanding of their underlying disease pathogenesis will encourage the development of more effective treatments that can target distinct disease pathways with greater specificity while minimizing adverse effects.

Clinical implications of immune-mediated diseases in children with Down syndrome

Children with Down syndrome have changes in their innate and adaptive immunity, which contribute to increased rates of infections, autoimmune diseases, and haematological malignancies. While improved care for congenital heart disease has decreased mortality and morbidity, complications related to immune-mediated diseases continue to limit the life expectancy in Down syndrome. Infectious diseases are common and have a significant effect on development, behaviour and quality of life. Infection frequency and severity are influenced by various anatomical and physiological alterations in addition to immunological changes in Down syndrome. Thus, prevention of respiratory tract infections requires a multifactorial approach. This could include additional active and/or passive immunizations, prophylactic antibiotics, immunoglobulin replacement and ear, nose and throat surgical interventions. Autoimmune conditions like coeliac disease, type I diabetes mellitus and thyroid disease are classically mentioned in the context of Down syndrome. However, autoinflammatory conditions are more prevalent as well. Screening for autoimmune diseases is required and immunosuppression has to be used with caution. Future studies should address optimal screening programmes for immune-mediated diseases in individuals with Down syndrome, as well as the effect of immune modulation, to further decrease morbidity and mortality, and improve the quality of life of individuals with Down syndrome.

Alopecia Areata: a Comprehensive Review of Pathogenesis and Management

Alopecia areata is a common hair loss condition that is characterized by acute onset of non-scarring hair loss in usually sharply defined areas ranging from small patches to extensive or less frequently diffuse involvement. Depending on its acuity and extent, hair loss is an important cause of anxiety and disability. The current understanding is that the condition represents an organ-specific autoimmune disease of the hair follicle with a genetic background. Genome-wide association studies provide evidence for the involvement of both innate and acquired immunity in the pathogenesis, and mechanistic studies in mouse models of alopecia areata have specifically implicated an IFN-γ-driven immune response, including IFNγ, IFNγ-induced chemokines and cytotoxic CD8 T cells as the main drivers of disease pathogenesis. A meta-analysis of published trials on treatment of alopecia areata states that only few treatments have been well evaluated in randomized trials. Nevertheless, depending on patient age, affected surface area and disease duration, an empiric treatment algorithm can be designed with corticosteroids and topical immunotherapy remaining the mainstay of therapy. The obviously limited success of evidence-based therapies points to a more important complexity of hair loss. At the same time, the complexity of pathogenesis offers opportunities for the development of novel targeted therapies. New treatment opportunities based on the results of genome-wide association studies that implicate T cell and natural killer cell activation pathways are paving the way to new approaches in future clinical trials. Currently, there are ongoing studies with the CTLA4-Ig fusion protein abatacept, anti-IL15Rβ monoclonal antibodies and the Janus kinase inhibitors tofacitinib, ruxolitinib and baricitinib. Ultimately, the options available for adapting to the disease rather than treating it in an effort to cure may also be taken into consideration in selected cases of long-standing or recurrent small spot disease.

Insignificant Correlation between Thyroid Hormone and Antithyroid Peroxidase Antibodies in Alopecia Areata Patients in Northern Rajasthan

Background

Alopecia areata (AA) is a common, recurrent form of nonscarring alopecia which often presents as circumscribed patches of spontaneous hair loss. The global prevalence of this disease varies from 0.1% to 0.2% in general population and 7-30 cases per 1000 dermatological patients. The etiology of AA still remains uncertain; however, genetic or environmental factor and autoimmunity are claimed responsible for it. Various autoimmune diseases, such as Hashimoto's thyroiditis, diabetes mellitus, vitiligo, and lupus erythematosus, have been reported in association with AA.

Aim

The index study was aimed at estimation of serum T3, T4, thyroid-stimulating hormone, and antithyroid peroxidase (TPO) antibodies.

Material and Methods

Similar age/sex-matched AA patients and controls (110 in each group). Enhanced chemiluminescence immunoassay for thyroid profile and anti-TPO antibody level estimation in veinous blood sample.

Observations

The mean/standard deviation (SD) of T3 was 3.30 ± 0.84 pg/ml in AA while 3.27 ± 0.67 pg/ml in controls (P = 0.302). Serum mean/SD of T4 level was1.23 ± 0.76 ng/dl in AA patients while 1.17 ± 0.34 ng/dl in controls (P = 0.522). The mean/SD of anti-TPO levels in AA patients was 21.52 ± 35.09 while 56.43 ± 140.72 in controls (P = 0.136).

Limitation

The limitation of this study was moderate number of AA patients and different genotype of study population.

Conclusion

Occurrence of thyroid dysfunction and evidence of anti-TPO antibodies in AA is rare event in this study population.

Association among Thyroid Dysfunction, Asthma, Allergic Rhinitis and Eczema in Children with Alopecia Areata

BACKGROUND

Alopecia areata is a non-scarring hair loss, which typically starts quickly. Atopy is one of the possible predisposing risk factors for this condition.

AIM

This study aimed to evaluate the prevalence of thyroid disease, atopic dermatitis and allergic diseases in children with alopecia areata and compare the results with healthy individuals.

METHODS

This case-control study was conducted on 50 patients with alopecia areata, diagnosed by a dermatologist, and 150 healthy individuals as the control group. Participants filled the questionnaires, and necessary tests were performed.

RESULTS

In this study, the mean age of the participants was 2.55 ± 14.26 and 3.19 ± 11.92 in the case and control groups, respectively. Prevalence of asthma was 22% in the case group and 12.5% in control group (P = 0.109). Also, allergic rhinitis and eczema were observed in 20% and 22% of the subjects of the case group, whereas they were reported to be 8% and 10% in the control group (PV = 0.03 and 0.175, respectively). Moreover, 28% and 8% of the participants in the case and control groups had a family history of atopy and allergic disorders, respectively (P = 0.046). A significant difference was observed between the two groups regarding gender, type of delivery and contact with animals.

CONCLUSIONS

According to the results of this study, a significant association was observed between the prevalence of alopecia areata and atopic conditions, such as allergic rhinitis and history of atopic dermatitis.

Mechanisms of tolerance and potential therapeutic interventions in Alopecia Areata

This review aims to address the mechanisms of compromised immune tolerance contributing to the development and maintenance of Alopecia Areata (AA). Our goal is to also highlight future treatment opportunities and therapeutics that will safely and efficiently restore hair growth and maintain patients in remission. AA is a presumptive autoimmune disorder that coincides and genetically clusters to several other autoimmune diseases. In this review, we pay attention to the learnings from the mechanistic research and drug development in these other autoimmune conditions. Interestingly, most of these diseases have been linked to compromised central and peripheral tolerance, and increased intestinal inflammation with enhanced gut permeability. Break of tolerance and priming of the autoreactive T-cells to attack antigenic epitopes in the hair follicle most likely requires several steps which include escape from negative selection and compromised peripheral tolerance. Local skin-related changes are also of importance due to the patchy manifestation of the skin areas with loss of hair, particularly in the early disease. Here, we discuss the defective mechanisms of tolerance, both central and peripheral, and hypothesize that the disease is driven by areas of tolerance break, and that these could be targeted for successful therapeutic interventions.

Angioedema After Squaric Acid Treatment in a 6-Year-Old Girl

Alopecia areata (AA) involves the immune-related destruction of hair follicles, resulting in patches of complete hair loss, most often on the scalp. The topical sensitizer squaric acid dibutylester (SADBE) is a popular treatment option given its low side-effect profile, hair regrowth potential, and lack of cross-reactivity with other chemicals. We describe a unique case of a 6-year-old girl who developed angioedema after SADBE treatment for AA.

Transient Efficacy of Tofacitinib in Alopecia Areata Universalis

Alopecia areata is a common autoimmune disorder that targets hair follicles. Swarms of lymphocytes surround the basis of the follicles, inducing loss of pigmented terminal hair and subsequently inhibit further hair growth. Depending on the extent of involvement, alopecia areata can be associated with a dramatic reduction of quality of life. Currently, no targeted treatment option is available, and topical immune therapies or immunosuppressive drugs are typically used with mixed success. Recently, several cases of alopecia areata responding to Janus kinase inhibitors were published. Here, we report on a businessman with alopecia areata universalis who was treated with tofacitinib. We observed initial signs of hair regrowth in the same timeframe as previously reported, but efficacy quickly waned again, leading to renewed effluvium. Thus, even though tofacitinib and ruxolitinib are a promising new treatment option, we have yet to learn more about their potential role in each particular patient's individual treatment strategy.

The Frequency of Autoimmune Thyroid Disease in Alopecia Areata and Vitiligo Patients

Aim. Many studies demonstrated that alopecia areata (AA) and vitiligo are commonly associated with autoimmune thyroid diseases. We aimed to investigate the frequency of thyroid dysfunctions and autoimmunity related with vitiligo and AA. Material and Methods. 200 patients, 92 AA and 108 vitiligo diagnosed, were surveyed retrospectively. The control population was in reference range and from Konya, central Anatolian region of Turkey. Thyroid function tests (free T₃, free T₄, and TSH) and serum thyroid autoantibody (anti-TG, anti-TPO) levels were evaluated in all patients. Results. In vitiligo patients, 9 (8.3%) had elevated anti-TG levels and 16 (14.8%) had elevated anti-TPO, and in 17 patients (15.7%) TSH levels were elevated and 3 (2.8%) patients had elevated fT₄ levels and 5 (4.6%) had elevated fT₃ levels. Within AA patients, 2 (2.2%) had anti-TG elevation and 13 (14.1%) had anti-TPO elevation, in 7 patients (7.6%) TSH were elevated, and in 1 patient (1.1%) fT₄ were elevated and 5 (5.4%) patients had elevated fT₃ levels. Conclusion. In our study, impaired thyroid functions and thyroid autoantibodies in vitiligo and AA patients were identified at lower rates than the previous studies. According to results of this study there is no need for detailed examination in alopecia areata and vitiligo patients without clinical history.

Disease risk factors identified through shared genetic architecture and electronic medical records

Genome-wide association studies have identified genetic variants for thousands of diseases and traits. We evaluated the relationships between specific risk factors (for example, blood cholesterol level) and diseases on the basis of their shared genetic architecture in a comprehensive human disease-single-nucleotide polymorphism association database (VARIMED), analyzing the findings from 8962 published association studies. Similarity between traits and diseases was statistically evaluated on the basis of their association with shared gene variants. We identified 120 disease-trait pairs that were statistically similar, and of these, we tested and validated five previously unknown disease-trait associations by searching electronic medical records (EMRs) from three independent medical centers for evidence of the trait appearing in patients within 1 year of first diagnosis of the disease. We validated that the mean corpuscular volume is elevated before diagnosis of acute lymphoblastic leukemia; both have associated variants in the gene IKZF1. Platelet count is decreased before diagnosis of alcohol dependence; both are associated with variants in the gene C12orf51. Alkaline phosphatase level is elevated in patients with venous thromboembolism; both share variants in ABO. Similarly, we found that prostate-specific antigen and serum magnesium levels were altered before the diagnosis of lung cancer and gastric cancer, respectively. Disease-trait associations identify traits that could serve as future prognostics, if validated through EMR and subsequent prospective trials.

Angiotensin converting enzyme activity in alopecia areata

Background. Alopecia areata (AA) is a chronic inflammatory disease of the hair follicle. The exact pathogenesis of AA remains unknown, although recent studies support a T-cell mediated autoimmune process. On the other hand, some studies have proposed that the renin-angiotensin-aldosterone system (RAAS) may play a role in autoimmunity. Therefore, we assessed serum activity of angiotensin converting enzyme (ACE), a component of this system, in AA. Methods. ACE activity was measured in the sera of 19 patients with AA and 16 healthy control subjects. In addition, the relationship between severity and duration of the disease and ACE activity was evaluated. Results. Serum ACE activity was higher in the patient group (55.81 U/L) compared to the control group (46.41 U/L), but the difference was not statistically significant (P = 0.085). Also, there was no correlation between ACE activity and severity (P = 0.13) and duration of disease (P = 0.25) in the patient group. Conclusion. The increased serum ACE activity found in this study may demonstrate local involvement of the RAAS in the pathogenesis of AA. Assessment of ACE in a study with a larger sample size as well as in tissue samples is recommended in order to further evaluate the possible role of RAAS in AA.

Thyroid disorders associated with alopecia areata in egyptian patients

CONTEXT

Alopecia areata (AA) is a common form of localized, non-scarring hair loss. The etiopathogenesis of the disease is still unclear, but the role of autoimmunity is strongly suggested. AA is commonly associated with various autoimmune disorders; the most frequent among them is autoimmune thyroid disorders.

AIM

To determine whether AA is associated with thyroid autoimmunity or thyroid function abnormalities in Egyptian patients.

MATERIALS AND METHODS

Fifty subjects with AA (37 males and 13 females) without clinical evidence of thyroid disorders were selected from Dermatology Outpatient Clinic, Menoufiya University Hospital, Menoufiya Governorate, Egypt, during the period from June 2009 to February 2010. They were divided into 3 groups according to severity of AA. Fifty age and sex-matched healthy volunteers (35 males and 15 females) were selected as a control group. Every case and control were subjected to history taking, complete general and dermatological examination. Venous blood samples were taken from cases and controls after taking their consents for measurement of thyroid stimulating hormone (TSH), free T3, freeT4 and detection of Anti-thyroglobulin Antibody (Tg-Ab) and Anti-thyroid Peroxidase Antibody (TPO-Ab).

RESULTS

Subclinical hypothyroidism was detected in 16% of cases. There were statistically significant differences between cases and controls regarding levels of TSH, free T3 and free T4. There were significant differences between cases and controls regarding the presence of Tg-Ab and TPO-Ab.

CONCLUSIONS

Every patient with AA should be screened for thyroid functions and presence of thyroid autoantibodies even in absence of clinical manifestations suggestive of thyroid affection.

What causes alopecia areata?

The pathobiology of alopecia areata (AA), one of the most frequent autoimmune diseases and a major unsolved clinical problem, has intrigued dermatologists, hair biologists and immunologists for decades. Simultaneously, both affected patients and the physicians who take care of them are increasingly frustrated that there is still no fully satisfactory treatment. Much of this frustration results from the fact that the pathobiology of AA remains unclear, and no single AA pathogenesis concept can claim to be universally accepted. In fact, some investigators still harbour doubts whether this even is an autoimmune disease, and the relative importance of CD8(+) T cells, CD4(+) T cells and NKGD2(+) NK or NKT cells and the exact role of genetic factors in AA pathogenesis remain bones of contention. Also, is AA one disease, a spectrum of distinct disease entities or only a response pattern of normal hair follicles to immunologically mediated damage? During the past decade, substantial progress has been made in basic AA-related research, in the development of new models for translationally relevant AA research and in the identification of new therapeutic agents and targets for future AA management. This calls for a re-evaluation and public debate of currently prevalent AA pathobiology concepts. The present Controversies feature takes on this challenge, hoping to attract more skin biologists, immunologists and professional autoimmunity experts to this biologically fascinating and clinically important model disease.

Pili annulati coincident with alopecia areata, autoimmune thyroid disease, and primary IgA deficiency: case report and considerations on the literature

Pili annulati is a rare autosomal dominant hair disorder clinically characterized by a pattern of alternating bright and dark bands of the hair, the bright bands appearing dark if observed by transmitted light. This pattern is due to the periodic occurrence of air-filled cavities along the hair cortex which scatter and reflect the light while precluding its transmission. A susceptibility region, including a possibly responsible Frizzled gene, has been mapped to the telomeric region of chromosome 12q, although a specific mutation has not been identified. The condition has sometimes been observed in concurrence with alopecia areata, and in this paper we report a case in whom the concomitant severe alopecia areata was associated with autoimmune thyroid disease and primary IgA deficiency - a quadruple complex which, to our knowledge, has never been previously described. The occurrence of multiple immune disorders in the same patient affected by pili annulati could represent a key to understanding the high prevalence of alopecia areata in this condition. Specifically, in individuals predisposed to autoimmune disease, the molecular alterations that cause the anatomical changes of pili annulati could prompt the immune response against the hair root that underlies alopecia areata.

Regrowth of black hair in two red-haired alopecia areata patients

The occurrence of alopecia areata (AA) in a red-haired individual is considered to be rare. We report two cases of red-haired men who were afflicted with patch-type AA. Astonishingly, the hair regrowth was coloured black, in contrast to the surrounding red hair, an event which has been reported only once in the past after cyclophosphamide administration. This phenomenon raises some interesting questions regarding the significance of pigmentation and the melanocortin-1 receptor in AA pathogenesis.

Etiopathogenesis of alopecia areata: Why do our patients get it?

Alopecia areata (AA) is a nonscarring, inflammatory skin disease that results in patchy hair loss. AA is unpredictable in its onset, severity, and duration making it potentially very stressful for affected individuals. Currently, the treatment options for AA are limited and the efficacy of these treatments varies from patient to patient. The exact etiology of AA is unknown. This article provides some insights into the etiopathogenesis of AA and why some people develop it. The current knowledge on the pathogenesis of AA is summarized and some of the recent hypotheses and studies on AA are presented to allow for a fuller understanding of the possible biological mechanisms of AA.

Alopecia areata in Eringer cows

Alopecia areata is a hair loss disorder in humans, dogs and horses with a suspected autoimmune aetiology targeting anagen hair follicles. Alopecia areata is only sporadically reported in cows. Recently, we observed several cases of suspected alopecia areata in Eringer cows. The aim of this study was to confirm the presumptive diagnosis of alopecia areata and to define the clinical phenotype and histopathological patterns, including characterization of the infiltrating inflammatory cells. Twenty Eringer cows with alopecia and 11 Eringer cows without skin problems were included in this study. Affected cows had either generalized or multifocal alopecia or hypotrichosis. The tail, forehead and distal extremities were usually spared. Punch biopsies were obtained from the centre and margin of alopecic lesions and normal haired skin. Histological examination revealed several alterations in anagen hair bulbs. These included peri- and intrabulbar lymphocytic infiltration, peribulbar fibrosis, degenerate matrix cells with clumped melanosomes and pigmentary incontinence. Mild lymphocytic infiltrative mural folliculitis was seen in the inferior segment and isthmus of the hair follicles. Hair shafts were often unpigmented and dysplastic. The large majority of infiltrating lymphocytes were CD3(+) T cells, whereas only occasional CD20(+) lymphocytes were present in the peribulbar infiltrate. Our findings confirm the diagnosis of T-cell-mediated alopecia areata in these cows. Alopecia areata appears to occur with increased frequency in the Eringer breed, but distinct predisposing factors could not be identified.

Alopecia areata is not associated with Helicobacter pylori

Background:

Alopecia areata (AA) is an immune-mediated form of hair loss that occurs in all ethnic groups, ages, and both sexes. Helicobacter pylori has been associated with many extra-digestive dermatological conditions. The causal relation between alopecia areata and Helicobacter pylori is discussed in this study.

Materials and Methods:

We have screened for the presence of H. pylori in patients with AA, in order to determine any potential role in its patho-physiology. We have prospectively studied 31 patients with alopecia areata and 24 healthy volunteers of similar gender, for the presence of H. pylori stool antigen (HpSAg).

Results:

Optical density values for H. pylori infection was positive in 18 of the 31 patients evaluated (58.1%), while in 13 patients, the values did not support H. pylori infection (41.9%). In the control group, 10 of the 24 (41.7%) had positive results. Within the group of alopecia areata, there was no significant difference between HpSAg positive and negative patients.

Conclusions:

The results have shown that a relation between Helicobacter pylori and alopecia areata is not supported. We advise that H. pylori detection need not to be included in the laboratory work up of alopecia areata.

Alopecia Areata Associated with Localized Vitiligo

Alopecia areata is a common cause of noncicatricial alopecia that occurs in a patchy, confluent or diffuse pattern. It may occur as a single, self-limiting episode or may recur at varying intervals over many years. The association of alopecia areata with localized vitiligo has not been reported. The association of alopecia areata with localized vitiligo in the same patient is documented here; it is the first of its kind.

Alopecia areata update: part I. Clinical picture, histopathology, and pathogenesis

Alopecia areata (AA) is an autoimmune disease that presents as nonscarring hair loss, although the exact pathogenesis of the disease remains to be clarified. Disease prevalence rates from 0.1% to 0.2% have been estimated for the United States. AA can affect any hair-bearing area. It often presents as well demarcated patches of nonscarring alopecia on skin of overtly normal appearance. Recently, newer clinical variants have been described. The presence of AA is associated with a higher frequency of other autoimmune diseases. Controversially, there may also be increased psychiatric morbidity in patients with AA. Although some AA features are known poor prognostic signs, the course of the disease is unpredictable and the response to treatment can be variable. Part one of this two-part series on AA describes the clinical presentation and the associated histopathologic picture. It also proposes a hypothesis for AA development based on the most recent knowledge of disease pathogenesis.

LEARNING OBJECTIVES

After completing this learning activity, participants should be familiar with the most recent advances in AA pathogenesis, recognize the rare and recently described variants of AA, and be able to distinguish between different histopathologic stages of AA.

Alopecia areata: evidence-based treatments

Alopecia areata is a common condition causing nonscarring hair loss. It may be patchy, involve the entire scalp (alopecia totalis) or whole body (alopecia universalis). Patients may recover spontaneously but the disorder can follow a course of recurrent relapses or result in persistent hair loss. Alopecia areata can cause great psychological distress, and the most important aspect of management is counseling the patient about the unpredictable nature and course of the condition as well as the available effective treatments, with details of their side effects. Although many treatments have been shown to stimulate hair growth in alopecia areata, there are limited data on their long-term efficacy and impact on quality of life. We review the evidence for the following commonly used treatments: corticosteroids (topical, intralesional, and systemic), topical sensitizers (diphenylcyclopropenone), psoralen and ultraviolet A phototherapy (PUVA), minoxidil and dithranol.

The role of T cells in cutaneous autoimmune disease

T cells assume a fundamental function in immunosurveillance and maintenance of the cutaneous immune barrier, yet derangement of their requisite role effects a range of cutaneous autoimmune diseases with significant associated morbidity. While blistering skin diseases, such as pemphigus vulgaris (PV), pemphigus foliaceus (PF) and bullous pemphigoid (BP) are mediated by antibodies directed against autoantigens found in the skin, recent evidence has shown that T cell activation is crucial for the initiation and coordination of this humoral response. Non-blistering skin diseases, such as alopecia areata (AA), vitiligo (VL) and psoriasis (PS) are increasingly believed to be directly mediated by the activities of autoreactive T cells. Here, we examine T lymphocyte control of antibody-mediated and cell-mediated processes involved in the pathoimmunology of the above mentioned skin diseases.

Alopecia areata and autoimmunity: a clinical study

Alopecia areata (AA) frequently occur in association with other autoimmune diseases such as thyroid disorders, anemias and other skin disorders with autoimmune etiology. Despite numerous studies related to individual disease associations in alopecia areata, there is paucity of literature regarding comprehensive studies on concomitant cutaneous and systemic diseases. The present study has been designed to determine if there is a significant association between alopecia areata and other autoimmune diseases. This study covers 71 patients with the diagnosis of alopecia areata as the case group and 71 patients with no evidence of alopecia areata as the control group. Among the cutaneous diseases associated with AA, atopic dermatitis (AD) showed maximum frequency with an O/E ratio of 2.5, which indicates that it is two to three times more common in patients with alopecia areata. In our study, thyroid disorders showed the highest frequency with on O/E ratio of 3.2 and a P value of 0.01, which is statistically highly significant. Among the thyroid disorders, hypothyroidism was the most frequent association (14.1%) in our study. Since systemic involvement is not infrequent in patients with alopecia areata, it is imperative to screen these patients for associated disorders, particularly atopy, thyroid diseases, anemias and other autoimmune disorders, especially if alopecia areata is chronic, recurrent and extensive.

Alopecia areata

Alopecia areata (AA) is a nonscarring, autoimmune, inflammatory, hair loss on the scalp, and/or body. Etiology and pathogenesis are still unknown. The most common site affected is the scalp. Histopathology is characterized by an increased number of the catagen and telogen follicles, the presence of inflammatory lymphocytic infiltrate in the peribulbar region ("swarm of bees"). Corticosteroids are the most popular drugs for the treatment of this disease. Etiologic and pathogenic mechanisms, as well as other current treatments available will be discussed in this article.

Use of the pulsed infrared diode laser (904 nm) in the treatment of alopecia areata

BACKGROUND

Alopecia areata is a rapid and complete loss of hair in one or several patches, usually on the scalp, affecting both males and females equally. It is thought to be an autoimmune disease which is treated with different modalities with variable success. Laser treatment of different wavelengths has been used in the management of this problem.

OBJECTIVE

To study the effect of the pulsed infrared diode laser (904 nm) in the treatment of alopecia areata.Methods. Sixteen patients with 34 resistant patches that had not responded to different treatment modalities for alopecia areata were enrolled in this study. In patients with multiple patches, one patch was left as a control for comparison. Patients were treated on a four-session basis, once a week, with a pulsed diode laser (904 nm) at a pulse rate of 40/s. A photograph was taken of each patient before and after treatment.

RESULTS

The treated patients were 11 males (68.75%) and five females (31.25%). Their ages ranged between 4 and 50 years with a mean of 26.6+/-SD of +/-13.8, and the durations of their disease were between 12 months and 6 years with a mean of 13.43+/-SD of +/-18.34. Regrowth of hair was observed in 32 patches (94%), while only two patches (6%) failed to show any response. No regrowth of hair was observed in the control patches. The regrowth of hair appeared as terminal hair with its original color in 29 patches (90.6%), while three patches (9.4%) appeared as a white villous hair. In patients who showed response, the response was detected as early as 1 week after the first session in 24 patches (75%), while eight patients (25%) started to show response from the second session.

CONCLUSION

The pulsed infrared diode laser is an effective mode of therapy with a high success rate for resistant patches of alopecia areata.

Evaluation of the profile of alopecia areata and the prevalence of thyroid function test abnormalities and serum autoantibodies in Iranian patients

BACKGROUND

The study aimed at evaluating the prevalence of thyroid function abnormalities in patients with alopecia areata (AA) and its association with other autoimmune diseases and various autoimmune antibodies.

METHOD

We retrospectively analyzed medical records of 123 patients with AA. The main site of involvement, pattern, and extent of alopecia as well as presence of the similar disease in first-degree family members and serologic status of patients were recorded.

RESULTS

Participating in the study were 57 males and 66 females (6 to 59 years old). In the majority of patients (69.9%) the disease was manifested in the first two decades of life. Patients with family members having alopecia were recorded in 24.4%. Thyroid function abnormalities were found in 8.9% of patients. Positive autoimmune antibodies were associated with AA in 51.4% of patients with no significant association between the severity and duration of disease and presence of these antibodies.

CONCLUSION

The incidence of positive auto-immune antibodies in Iranian patients is higher than previous reports. Concerning the female:male ratio, thyroid function tests and the prevalence of alopecia in first-degree relatives, our results are compatible with previous data obtained from different ethnic populations. Previous reports documented that a greater severity and longer duration of AA were seen in the early onset forms; however our result are relatively different which could be explained by differences in genetic factors.