Acquired Idiopathic Generalized Anhidrosis (AIGA) and Its Complications: Implications for AIGA as an Autoimmune Disease.

Acquired idiopathic generalized anhidrosis (AIGA) is a rare disorder in which systemic anhidrosis/hypohidrosis occurs without causative dermatological, metabolic or neurological disorder. Most cases of AIGA have been reported in Asia, especially in Japan, but there have been only a few reports in Europe and the United States. Severe AIGA may result in heatstroke and can reduce quality of life due to restriction of exercise and outdoor works. AIGA is often accompanied by cholinergic urticaria (CholU), and it is thought that AIGA and CholU with anhidrosis/hypohidrosis belong to the same spectrum of the disease. However, the pathophysiology of AIGA has not yet been clarified. Decreased expression of cholinergic receptor M3 on the epithelial cells of eccrine sweat glands is often accompanied by T cell infiltration around eccrine apparatus, suggesting an immunological mechanism of disordered perspiration. AIGA is occasionally associated with various complications indicative of autoimmune disorders. The association of autoimmune complications further suggests that AIGA is an autoimmune disorder. Studies on complications may lead to a better understanding of the pathophysiology of AIGA.

Hypohidrosis as an immune-related adverse event of checkpoint inhibitor therapy.

Background: Immune checkpoint blockade therapies including cytotoxic-T-lymphocyte antigen 4 (CTLA-4) and programmed cell death protein-1 (PD-1) inhibitors have become indispensable tools for treating melanoma and other cancers. An increasing number of diverse cutaneous adverse reactions to immunotherapy have been documented in the literature and have been reported to affect up to 40% of patients treated with targeted therapies. Method & results: Herein, we report a case of a patient with metastatic melanoma treated with checkpoint inhibitor therapy who developed vitiligo, gastritis and hepatitis, all identified as adverse immune events and attributable to his immunotherapy regimen. He subsequently developed acquired idiopathic generalized hypohidrosis with biopsy of lesional skin demonstrating a peri-eccrine lymphocytic infiltrate. Conclusion: These findings suggest this acquired generalized hypohidrosis represents a lymphocyte-mediated adverse immune event related to this patient's checkpoint inhibitor therapy.

Is Ross Syndrome an Autoimmune Entity? A Case Series of 11 Patients.

BACKGROUND: Ross syndrome is diagnosed by the presence of segmental anhidrosis, areflexia, and tonic pupils. Fewer than 60 cases have been described in literature so far. There have been reports of presence of antibodies in such patients, suggesting an autoimmune pathogenesis. METHODS: We describe the clinical profile in this case series of 11 patients with Ross syndrome and discuss the current status of autoimmunity in its pathogenesis and the management. RESULTS: Of the 11 patients with Ross syndrome there was an almost equal sex distribution (male:female ratio was 1.17:1) and the mean age of onset of symptoms was 26 years. Patients took an average of 6 years to present to a tertiary center. Sixty-three percent of the patients presented with complaints of excessive sweating, whereas only 27% had complaints of decreased sweating over a particular area of the body. Only 45% of the patients had the complete triad of Ross syndrome, which included segmental anhidrosis, tonic pupil, and absent reflexes. Eighty-nine percent of the patients had documented absent sympathetic skin response on electromyography. The various markers of autoimmunity were negative in all patients who were investigated for the same in this series. Ninety percent of the patients were managed conservatively. CONCLUSIONS: These findings suggest that, in Ross syndrome, generalized injury to ganglion cells or their projections are not purely autoimmune-mediated.

Congenital insensitivity to pain and anhidrosis: Case report and review of findings along neuro-immune axis in the disorder.

Congenital insensitivity to pain and anhidrosis (CIPA) is one of the hereditary autonomic and sensory neuropathies. Typically presenting in infancy, it manifests as hyperpyrexia from defects in sweating (autonomic) and self-mutilating injuries from pain insensitivity (sensory). CIPA being rare in North America, diagnosis is often missed due to variable presentation. Subsequent management of its complications is therefore delayed. We report an unusual presentation in a 2-year-old girl with preexisting diagnosis of CIPA who was evaluated for bilateral upper extremity paresis of insidious onset. MRI revealed a mass compressing her cervical spine as the cause, and work up suggested immune dysfunction as possible etiology. To our knowledge, this complication has not been reported before in association with the disease. We introduce the disease by explaining the molecular pathology behind its presenting features. The neurological findings, documented in association with CIPA, are summarized and serve as a reference for the various presentations of this rare disorder. Since this disease is known to affect the immune system, immune defects in CIPA are discussed with recommendations for surveillance of patient's immune status.

Abberant Sudomotor Functions in Sjögren's Syndrome: Comparable Study with Atopic Dermatitis on Dry Skin Manifestation.

This chapter summarizes recent advances in the pathogenesis and management of Sjögren's syndrome (SS). Major topics are newly described pathomechanisms and cutaneous manifestations of SS, with special references to hypohidrosis and related mucocutaneous manifestations. Although the significance of cutaneous manifestations in SS has been gradually recognized in rheumatologists, sudomotor function has not been fully evaluated and recognized in the diagnosis of SS except by dermatologists. SS is a relatively underestimated collagen disease in contrast to systemic lupus erythematosus, systemic sclerosis, or dermatomyositis, and special care is needed not to misdiagnose SS when we see patients with common skin diseases such as drug eruption, infectious skin disease, or xerosis in daily practice. In contrast to SS, the reduced sweating function seen in atopic dermatitis (AD) is restricted only to axon reflex-induced indirect sweating, which is usually restored to normal levels after improvement of the dermatitis. Therefore, the xerotic skin lesions seen in SS and AD might be attributable to different pathomechanisms with similar dry skin manifestations. It is well known that dry skin is occasionally seen in SS, and clinical use of muscarinic M3-receptor agonists occasionally improves this condition through recovery of sweating function. Therefore, this M3-receptor agonist might be a promising drug and should be evaluated for the treatment of impaired sweating in AD complicated with or without SS.

New Etiology of Cholinergic Urticaria.

Cholinergic urticaria (CholU) is characterized by pinpoint-sized, highly pruritic wheals occurring upon sweating. Both direct and indirect theories in the interaction of acetylcholine (ACh) with mast cells have been put forward in the sweating-associated histamine release from mast cells. In the mechanism of indirect involvement of ACh, patients are hypersensitive to sweat antigen(s) and develop wheals in response to sweat substances leaking from the syringeal ducts to the dermis, possibly by obstruction of the ducts. Some patients with CholU exhibit a positive reaction to intradermal injection of their own diluted sweat, representing 'sweat allergy (hypersensitivity)'. Regarding the direct interaction theory between ACh and mast cells, we found that CholU with anhidrosis and hypohidrosis lacks cholinergic receptor M3 (CHRM3) expression in eccrine sweat gland epithelial cells. The expression of CHRM3 is completely absent in the anhidrotic areas and lowly expressed in the hypohidrotic areas. In the hypohidrotic area, where CholU occurs, it is hypothesized that ACh released from nerves cannot be completely trapped by cholinergic receptors of eccrine glands and overflows to the adjacent mast cells, leading to wheals.

Serum carcinoembryonic antigen (CEA) as a clinical marker in acquired idiopathic generalized anhidrosis: a close correlation between serum CEA level and disease activity.

BACKGROUND: Hypohidrosis/anhidrosis are congenital or acquired sweating impairments. Among them, acquired idiopathic generalized anhidrosis/hypohidrosis (AIGA) is the most common, and characterized by favourable response to systemic corticosteroid, however, no clinical markers for disease severity or activity have been developed. OBJECTIVE: Our aim was to verify the usefulness of serum carcinoembryonic antigen (CEA) level monitoring as a clinical marker for disease activity of AIGA. METHODS: Ten cases of AIGA diagnosed at Asahikawa Medical University, from 1980 to 2014 were included in the study. CEA and/or CEACAM1 expression level was analysed using immunohistochemistry and enzyme-linked immunosorbent assay. RESULT: CEA expression was restricted to the apical membrane of glandular cells in eccrine sweat glands in most of the three types of cases we examined [healthy control, patients with atopic dermatitis (AD) or urticaria]. However, CEA expression was detected diffusely and much more intensively in eight of the 10 AIGA cases included in this study. CEACAM1-expression was much more restricted on the apical membrane of glandular cells of both the AIGA cases and the other control subjects. While serum CEA levels increased in all five AIGA cases examined (5.8-43.2 ng/mL), it remained within normal limits in all control subjects: nine healthy individuals; 10 cases of AD; 10 cases of idiopathic urticaria; four cases of normohidrotic cholinergic urticaria (Mann-Whitney's U-test, P < 0.05). The increased serum CEA levels in AIGA decreased in conjunction with improved sweating during methyl prednisolone pulse therapy or repeated bathing. CONCLUSION: Serum CEA level may serve as a clinical marker for AIGA activity.

Correlation of disease activity and serum level of carcinoembryonic antigen in acquired idiopathic generalized anhidrosis: A case report.

Hypohidrosis and anhidrosis are congenital or acquired conditions which are characterized by inadequate sweating. Acquired idiopathic generalized hypohidrosis/anhidrosis (AIGA) includes idiopathic pure sudomotor failure (IPSF), which has the following distinct features: sudden onset in youth, increased serum immunoglobulin E and responds favorably to systemic corticosteroid. No clinical markers reflecting the disease severity or activity have been established. Here, we report a case of AIGA in a Japanese patient successfully treated with repeated methylprednisolone pulse therapy. In this case, serum carcinoembryonic antigen (CEA) levels increased up to 19.8 ng/mL along with aberrant CEA immunoreactivity of eccrine sweat glands. Interestingly, the serum CEA level normalized as sweating improved with repeated methylprednisolone pulse therapy. Therefore, serum CEA level may serve as a useful clinical marker of hypohidrosis or anhidrosis.

Investigation of antimuscarinic receptor autoantibodies in patients with acquired idiopathic generalized anhidrosis.

OBJECTIVE: The autoimmune mechanism is considered to play an important role in the development of acquired idiopathic generalized anhidrosis (AIGA), and muscarinic M3 receptors (M3Rs) on eccrine glands are possible autoimmune targets. We investigated the existence of autoantibodies against M3Rs in AIGA patients. METHODS: We immunostained M3R-expressing cultured cells with the serum of 12 AIGA patients (mean age: 35.0±11.7 years, mean disease duration: 26.6±25.8 months) and 10 healthy subjects (mean age: 32.4±10.4 years). RESULTS: The surface of the M3R-expressing cells was stained by the serum obtained from one of the 12 AIGA patients but not by the serum obtained from the remaining 11 patients or healthy subjects. CONCLUSION: The presence of M3R autoantibodies may therefore be related to the underlying mechanism of disease in a subset of AIGA patients.

Four cases of atopic dermatitis complicated by Sjögren's syndrome: link between dry skin and autoimmune anhidrosis.

We report four adult cases of atopic dermatitis (AD) complicated by Sjögren's syndrome (SS). The patients fulfilled diagnostic criteria for AD and SS. All cases showed persistent itchy dry skin and eczematous lesions complicated by sicca symptoms including dry eyes and dry mouth with moderate joint pain. One case manifested annular erythema and another manifested widespread discoid erythema. To investigate the underlying cause of dry skin in these cases, sweating function was evaluated using a quantitative sudomotor axon reflex test (QSART) in which the axon reflex is stimulated by acetylcholine iontophoresis. The sweating latency time was significantly prolonged in eczematous skin of AD and AD/SS compared to normal controls. Axon reflex (AXR) sweat volume was also significantly reduced in AD (normal and eczematous skin) and AD/SS (normal and eczema) compared to normal control. In contrast, the direct sweat volume of lesional or non-lesional AD skin induced by direct stimulation with acetylcholine was only slightly reduced compared to that in normal controls, but not in SS and lesional skin of AD/SS patients. These results suggest that the impaired sweat response in AD is attributable to an abnormal sudomotor axon reflex, which is accelerated and modulated when complicated by SS resulting in dry skin in the present cases.

Timed NF-kappaB inhibition in skin reveals dual independent effects on development of HED/EDA and chronic inflammation.

We have shown earlier that inhibiting NF-kappaB activity in murine basal keratinocytes leads to hyperproliferation, inflammation, and cancer in a tumor necrosis factor receptor 1 (TNFR1)-dependent manner. We report here the outcomes of NF-kappaB abrogation at different stages of epidermal morphogenesis using a conditional IkappaBalpha transgenic mouse model. We find that blocking NF-kappaB during embryogenesis mimics the epidermal and glandular defects seen in the human disease hypohidrotic/anhidrotic ectodermal dysplasia (HED/EDA), independently of the inflammatory phenotype and TNFR1. The onset of transgene expression after birth correlates with nuclear exclusion of the NF-kappaB p50 subunit, hyperplasia, and development of a chronic inflammation initiated and dominated by macrophages. In this model, macrophages are important producers of the vascular endothelial growth factor A (VEGFA), whose inhibition attenuates the excessive angiogenesis otherwise observed. The inflammatory reaction requires the continuous suppression of NF-kappaB in keratinocytes, indicating that an immune cell attractant(s) is directly induced in response to NF-kappaB inhibition. As TNFalpha upregulation is a late event in this model, good candidates for such chemoattraction are the monocyte chemotactic proteins 1, 2, and 3 (MCP-1-2-3), which are upregulated in the epidermal compartment concomitantly with the onset of NF-kappaB inhibition.

Sudomotor testing predicts the presence of neutralizing botulinum A toxin antibodies.

The increasing number of patients being treated with botulinum toxin A complex (BoNT/A) has led to a higher incidence of neutralizing anti-BoNT/A antibodies (ABAs). Because BoNT/A is known to inhibit sweating, here we report sudometry as a possibility for predicting the presence of ABA. Sixteen patients suffering from spasmodic torticollis were selected: in 2 patients, BoNT/A treatment continued to be effective, in 9 patients, the treatment effect was impaired, and in 5 patients, secondary treatment failure developed. BoNT/A (100 mouse units, Dysport; Ipsen Pharma, Berkshire, United Kingdom) was injected subcutaneously into the lateral calves. Sweating was visualized with iodine starch staining. In addition, quantitative sudomotor axon reflex testing was performed at the injection site. Individual ABA titers were determined with a mouse bioassay. Results of sudometry significantly correlated with the BoNT/A treatment success. The quantitative sudomotor axon reflex testing was 0.58 +/- 0.63 fraction of the normal mean in patients with treatment failure, 0.18 +/- 0.13 fraction of the normal mean in those who responded partially, and 0 in responders (p < 0.01). Accordingly, the areas of the anhidrotic skin after subcutaneous injections were 4.5 +/- 10.3 cm(2), 32.7 +/- 16.5 cm(2), and 62 cm(2) (p < 0.01). Discrimination analysis indicated that the presence of ABA (6 ABA-positive and 10 ABA-negative) could be predicted correctly in all patients from the results of sudometry. Therefore, sudometry is a useful tool for identifying patients with neutralizing ABAs and might be helpful for identifying reasons for BoNT/A treatment failure.