Does autonomic dysfunction play a role in atopic dermatitis?

Arriving at SKINTED (Surgery of the Knee, Injury to the Infrapatellar Branch of the Saphenous Nerve, Traumatic Eczematous Dermatitis): A Case Report

Surgery of the knee, injury to the infrapatellar branch of the saphenous nerve, traumatic eczematous dermatitis (SKINTED) is a postsurgical localized dermatitis specifically linked to total knee arthroplasty (TKA). It is due to autonomic denervation following surgically inflicted nerve injury. It develops several months to years following a surgical trauma. It is being referred to by various names in the literature. Locoregional immune dysfunction due to lymphatic injury after surgery is the currently accepted theory. It must be distinguished from atopic dermatitis, allergic contact dermatitis/sensitization induced by topical medications or implanted metal hypersensitivity dermatitis, and post-traumatic eczema/dermatitis. We present a case of an elderly female patient in her 50s with dry eczematous lesions over the lateral aspect of the surgical incision over both knees developed three months following bilateral total knee replacement (TKR) done in view of osteoarthritis. The patient responded well to topical corticosteroid and emollient treatment. We have also reviewed the literature to provide an overview of potential concepts of etiopathogenesis described in the literature and to clear up any ambiguity surrounding various labels given to this entity.

Investigating causal relationships between obesity and skin barrier function in a multi-ethnic Asian general population cohort

BACKGROUND

Skin diseases impact significantly on the quality of life and psychology of patients. Obesity has been observed as a risk factor for skin diseases. Skin epidermal barrier dysfunctions are typical manifestations across several dermatological disturbances.

OBJECTIVES

We aim to establish the association between obesity and skin physiology measurements and investigate whether obesity may play a possible causal role on skin barrier dysfunction.

METHODS

We investigated the relationship of obesity with skin physiology measurements, namely transepidermal water loss (TEWL), skin surface moisture and skin pH in an Asian population cohort (n = 9990). To assess for a possible causal association between body mass index (BMI) and skin physiology measurements, we performed Mendelian Randomization (MR), along with subsequent additional analyses to assess the potential causal impact of known socioeconomic and comorbidities of obesity on TEWL.

RESULTS

Every 1 kg/m2 increase in BMI was associated with a 0.221% (95%CI: 0.144-0.298) increase in TEWL (P = 2.82E-08), a 0.336% (95%CI: 0.148-0.524) decrease in skin moisture (P = 4.66E-04) and a 0.184% (95%CI: 0.144-0.224) decrease in pH (P = 1.36E-19), adjusting for age, gender, and ethnicity. Relationships for both TEWL and pH with BMI remained strong (Beta 0.354; 95%CI: 0.189-0.520 and Beta -0.170; 95%CI: -0.253 to -0.087, respectively) even after adjusting for known confounders, with MR experiments further supporting BMI's possible causal relationship with TEWL. Based on additional MR performed, none of the socioeconomic and comorbidities of obesity investigated are likely to have possible causal relationships with TEWL.

CONCLUSION

We establish strong association of BMI with TEWL and skin pH, with MR results suggestive of a possible causal relationship of obesity with TEWL. It emphasizes the potential impact of obesity on skin barrier function and therefore opportunity for primary prevention.

Beneficial effects of oral supplementation with ferulic acid, a plant phenolic compound, on the human skin barrier in healthy men

Ferulic acid (FA) is a phytochemical compound with various physiologic functions. To clarify the effect of FA intake on skin barrier function (SBF), we conducted a placebo-controlled double-blind pilot trial. Sixteen healthy subjects were divided into 2 groups (n = 8) and ingested capsules containing either FA (200 mg) or placebo daily for 2 weeks. Two measures of SBF, transepidermal water loss and stratum corneum hydration, were assessed before and 2 weeks after the start of the study. Autonomic nervous activity, which is suggested to be related to SBF, was also measured. Compared with the values obtained before the start of the study, FA intake significantly reduced transepidermal water loss (from 6.1 ± 1.1 to 4.8 ± 1.0 g/m²/h, p = 0.005) and increased stratum corneum hydration (from 30.1 ± 7.6 to 32.3 ± 8.1 a.u., p = 0.027) after 2 weeks. In addition, the amount change in sympathetic nervous activity was significantly reduced after ingesting the FA capsules compared with the placebo capsules (-0.7 ± 1.6 vs. 1.1 ± 1.4, p = 0.035). These findings suggest that FA supplementation decreases sympathetic nervous activity and strengthens SBF in healthy men.

Role of antimicrobial peptides in atopic dermatitis

Host defense peptides (HDPs) or antimicrobial peptides (AMPs) are short cationic amphipathic peptides of divergent sequences, which are part of the innate immune system and produced by various types of cells and tissues. The predominant role of HDPs is to respond to and protect humans against infection and inflammation. Common human HDPs include defensins, cathelicidin, psoriasin, dermcidin, and ribonucleases, but these peptides may be dysregulated in the skin of patients with atopic dermatitis (AD). Current evidence suggests that the antimicrobial properties and immunomodulatory effects of HDPs are involved in AD pathogenesis, making HDPs research a promising area for predicting disease severity and developing novel treatments for AD. In this review, we describe a potential role for human HDPs in the development, exacerbation, and progression of AD and propose their potential therapeutic benefits.

Toward the Existence of a Sympathetic Neuroplasticity Adaptive Mechanism Influencing the Immune Response. A Hypothetical View-Part II

In the preceding work, a hypothesis on the existence of a specific neural plasticity program from sympathetic fibers innervating secondary lymphoid organs was introduced. This proposed adaptive mechanism would involve segmental retraction and degeneration of noradrenergic terminals during the immune system (IS) activation followed by regeneration once the IS returns to the steady-state. Starting from such view, this second part presents clinical and experimental evidence allowing to envision that this sympathetic neural plasticity mechanism is also operative on inflamed non-lymphoid peripheral tissues. Importantly, the sympathetic nervous system regulates most of the physiological bodily functions, ranging from cardiovascular, respiratory and gastro-intestinal functions to endocrine and metabolic ones, among others. Thus, it seems sensible to think that compensatory programs should be put into place during inflammation in non-lymphoid tissues as well, to avoid the possible detrimental consequences of a sympathetic blockade. Nevertheless, in many pathological scenarios like severe sepsis, chronic inflammatory diseases, or maladaptive immune responses, such compensatory programs against noradrenergic transmission impairment would fail to develop. This would lead to a manifest sympathetic dysfunction in the above-mentioned settings, partly accounting for their underlying pathophysiological basis; which is also discussed. The physiological/teleological significance for the whole neural plasticity process is postulated, as well.

Sympathetic dysfunction dermatitis in a revascularised upper extremity after near-total amputation - A case report and review of literature

Commonly reported complications after revascularisation or replantation of extremity are vascular thrombosis leading to complete or partial failure, bony non-union or malunion, joint stiffness and incomplete or abnormal sensory recovery. Sympathetic dysfunction dermatitis is an unreported complication after revascularisation or replantation surgery which results due to denervation of the extremity. We report a case of a young adult who developed eczematous dermatitis over the revascularised upper limb and discuss the role of sympathetic dysfunction in the development of these skin lesions. The patient was successfully treated with a short course of oral and topical steroids. Sympathetic dysfunction dermatitis is a rare form of skin eruptions occurring in the revascularised or replanted part of an extremity due to abnormal sympathetic function in the affected part.

Acupuncture for Histamine-Induced Itch: Association With Increased Parasympathetic Tone and Connectivity of Putamen-Midcingulate Cortex

Previous studies have suggested that acupuncture is effective for ameliorating itch intensity. However, factors associated with the antipruritic effects of acupuncture have yet to be clarified. In a randomized, sham-controlled, crossover trial, we investigated the antipruritic effects of acupuncture against histamine-induced itch in healthy volunteers. Autonomic changes using heart rate variability (HRV) and brain connectivity using functional magnetic resonance imaging (fMRI) were also assessed to identify physiological factors associated with the acupuncture response. Acupuncture significantly reduced itch intensity and skin blood perfusion as assessed by laser Doppler perfusion imaging compared to sham control, indicating the antipruritic effects of acupuncture. In responder and non-responder analysis, the power of normalized high frequency (HF norm) was significantly higher, while the power of normalized low frequency (LF norm) and LF/HF ratio were significantly lower in responders compared to non-responders, suggesting the acupuncture response involved parasympathetic activation. In fMRI analysis, the putamen and the posterior part of the midcingulate cortex (pMCC) were positively connected to itch and negatively correlated with itch intensity in responders. These results suggest that parasympathetic activity and functional connectivity of the putamen and pMCC could be associated with antipruritic response to acupuncture.

Quantity and quality of sweating in atopic dermatitis

Sweat may be an important factor in triggering an exacerbation of atopic dermatitis. It was the aim of this study to evaluate a possible correlation between atopic patients and hyperhidrosis-measured by a questionnaire-and to find out whether there are qualitative differences in sweat response-measured by sudomotor activity (sympathetic skin response test, SSR). Included were 100 study participants, of whom 50 were patients with atopic dermatitis and 50 were serving as control group. The frequency of hyperhidrosis is higher in atopic patients than in the control group (30 vs. 16%), but has no statistical significance. In addition, patients with hyperhidrosis and atopic dermatitis have a significantly higher exacerbation rate of atopic dermatitis in summertime. The group of atopic patients shows a statistically significant prolonged SSR latency period, which indicates an insufficient sympathetic innervation. In our tests, type IV allergic patients showed clear differences in terms of SSR latency and amplitude. Atopic patients have a higher incidence of hyperhidrosis. The study clearly shows that there is a dysfunction of sudomotor activity in the sympathetic nervous system of atopic patients. Our findings suggest that a deficient innervation of sweat glands in atopic patients may lead to an increase in the development of type IV allergies.

The Counterbalance of Skin Metabolism on Orbits and Diseases

Human organ functions are regulated by the nervous system. When human cells receive a message, this message is transmitted to the nervous system through a series of signal transmission processes. Skin conditions that occur after applying skin cream are closely related to signal transmission and nervous regulation. We determined the connection between signal regulation and natural rhythmic operations. The diurnal variations resulting from the earth’s rotation and indicate the relative relationships between the sympathetic nervous system and the parasympathetic nerve system. A spectrum was developed to assess neural transmission conditions by using skin signals which from Fourier transformation of the waves and established the association between the spectrum and diseases. The results could explain the relationships between the neurological illnesses and established spectrum. The objective was to promote the use of this spectrum as a new tool for conducting the nervous system tests in the future.

Pupillometric assessment of autonomic nervous system in children with allergic rhinitis

OBJECTIVE

The purpose of this study was to investigate autonomic nervous system dysfunction by measuring pupil sizes in pediatric patients with allergic rhinitis.

SUBJECTS AND METHODS

The study group consisted of 60 children (28 girls and 32 boys) who were age and gender matched with the control group, which also consisted of 60 children (26 girls and 34 boys). The diagnosis of allergic rhinitis was based on the history, physical examination and skin prick test performed by an allergologist. Pupil diameter measurements were performed using the pupillometer incorporated in the NİDEK OPD-Scan.

RESULTS

In the allergic rhinitis group, mean photopic and mesopic pupil diameters were 3.52 ± 0.07 and 5.98 ± 0.21, respectively, while in the control group, corresponding measurements were 4.03 ± 0.18 and 6.55 ± 0.16. There was a significant difference for photopic and mesopic pupil diameter between the groups (p < 0.001).

CONCLUSION

This study showed that the pupil size in response to a light stimulus in children with allergic rhinitis was smaller than that of the control group and may indicate parasympathetic hyperactivity and sympathetic hypoactivity.

Increased frequency of restless legs syndrome in atopic dermatitis

BACKGROUND

Restless legs syndrome (RLS) is characterized by an unpleasant sensation in the legs, which is difficult to describe, but produces an urge to move the legs frequently.

AIM

To assess the prevalence and severity of RLS in patients with atopic dermatitis (AD) and patients with psoriasis, and to investigate the factors potentially associated with RLS.

METHODS

In total, 253 people were enrolled (120 with AD, 50 with psoriasis and 83 healthy controls). A diagnosis of RLS was made according to the criteria of the International RLS Study Group (IRLSSG), and severity was assessed using the IRLSSG severity scale.

RESULTS

RLS was significantly more common in patients with AD (40.8%) than in patients with psoriasis (18.0%) or in controls (10.8%) (P<0.01 and P<0.001, respectively). Prevalence of RLS was higher in patients with active AD than in those with inactive AD (55.3% vs. 23.6%) or controls. There was a significant difference in RLS prevalence between patients with active and those with iactive AD, between patients with active AD and healthy controls, between patients with active AD and patients with psoriasis, and between patients with inactive AD and healthy controls (P<0.001, P<0.001, P<0.001, P=0.04, respectively). There was no significant difference in RLS prevalence between patients with active AD and patients with psoriasis, or between patients with psoriasis and healthy controls (P>0.05). Of patients who were positive for RLS, 56.9% had a family history of atopy and 40.3% had a family history of RLS, and there was a significant relationship between the presence of RLS and family history of atopy or RLS (P<0.001 for both).

CONCLUSIONS

RLS is common in patients with AD, particularly in those with active disease.

The investigation of autonomic functions in patients with psoriasis

BACKGROUND

Psoriasis is a common Th1-mediated skin disease whose etiology remains obscure. Loss of sweating caused by retention hyperkeratosis is seen in psoriasis plaques, which is likely to have resulted from autonomic dysfunction.

OBJECTIVE

In the present study, we aimed to evaluate autonomic nervous system (ANS) functions with regard to psoriasis and to examine whether there is an underlying ANS dysfunction.

MATERIALS AND METHODS

Fifty adult patients with plaque-type psoriasis and 20 healthy controls were enrolled in the present study. RESULTS  In this study, R-R interval variation (RRIV) was used to evaluate the parasympathetic system. No statistically significant difference was detected when RRIV values of the patient and the control groups were evaluated during normal and deep breathing (P > 0.05). It was determined that parasympathetic activity in the patient group remained unaffected. The sympathetic skin response (SSR) method was used for the evaluation of the sympathetic system. It was found that SSR latency and amplitude values of upper and lower extremities of the patient group were prolonged in comparison to those of the control group. The change in SSR latency of the upper extremity was found to be statistically significant (P < 0.05), whereas the changes in hand amplitude, foot latency, and foot amplitude values were not statistically significant (P > 0.05). It was determined that sympathetic activity in the patient group was affected.

CONCLUSION

In conclusion, we detected that a dysfunction was present in sympathetic nervous systems of patients with psoriasis. The parasympathetic nervous system functions were normal in patients with psoriasis.

Autonomic dysfunction and clinical severity of disease in children with allergic rhinitis

OBJECTIVES

The involvement of autonomic imbalance has been reported in the pathogenesis of allergic diseases.

PURPOSE

To investigate the association between the clinical severity of childhood allergic rhinitis and autonomic nervous system (ANS) dysfunction, to define whether the severity of disease correlates with ANS activity.

METHODS

In this cross-sectional, case-control study, we evaluated the ANS testing by measuring sympathetic skin response (SRR) and heart rate (R-R) interval variation (RRIV) in 55 children with perennial allergic rhinitis (PAR), aged 7-12 yrs without any chronic co-morbidity, and the results were compared with 40 sex- and age-matched control subjects. The patients were divided into two groups according to the severity of allergic rhinitis.

RESULTS

There were significant increase in calculated RRIV variables during at rest and deep breathing in children with PAR compared to controls, which reflect parasympathetic nervous system (PNS) activity (p<0.005). The mean amplitude of SSR in patients, which reflect sympathetic nervous system (SNS) activity was smaller compared with the controls, but this difference was not significant (0.61±0.35 μV vs controls 0.94±0.46, p>0.05). Lower RRIV and the prolonged SSR latencies in children with AR were closely correlated with disease severity (r=-0.65, p<0.05, and r=-0.59, p<0.05 respectively).

CONCLUSION

Combined use of these two tests, allows separate testing of PNS and SNS function, and are very sensitive methods in assessing of severity of disease in children with PAR.

Autonomic nervous system dysfunction and their relationship with disease severity in children with atopic asthma

The involvement of autonomic imbalance has been reported in the pathogenesis of allergic diseases. The aim of this study was to investigate the association between the clinical severity of childhood asthma with autonomic nervous system (ANS) dysfunction and to define whether the severity of asthma correlates with ANS activity. In this case-control study, we evaluated the ANS activity by testing heart rate variability (HRV) and sympathetic skin response (SRR) in 77 asthmatic children, age 7-12 yrs, who had no co-morbidity and compared them with 40 gender- and age-matched control subjects. According to the severity of their asthma, study subjects were further divided into three groups: I (mild asthmatics), II (moderate asthmatics), and III (severe asthmatics). Inter-group ANS scale scores differed significantly (p<0.01) between Groups I and III and between Groups II and III. Combined use of HRV and SSR provides a higher degree of sensitivity for assessing disease severity in cases of pediatric asthma.

Psychoneuroimmunology of psychological stress and atopic dermatitis: pathophysiologic and therapeutic updates

Atopic dermatitis is a chronic inflammatory skin disease characterized by impaired epidermal barrier function, inflammatory infiltration, extensive pruritus and a clinical course defined by symptomatic flares and remissions. The mechanisms of disease exacerbation are still poorly understood. Clinical occurrence of atopic dermatitis is often associated with psychological stress. In response to stress, upregulation of neuropeptide mediators in the brain, endocrine organs, and peripheral nervous system directly affect immune and resident cells in the skin. Lesional and non-lesional skin of patients with atopic dermatitis demonstrates increased mast cells and mast cell-nerve fiber contacts. In the setting of stress, sensory nerves release neuromediators that regulate inflammatory and immune responses, as well as barrier function. Progress towards elucidating these neuroimmune connections will refine our understanding of how emotional stress influences atopic dermatitis. Moreover, psychopharmacologic agents that modulate neuronal receptors or the amplification circuits of inflammation are attractive options for the treatment of not only atopic dermatitis, but also other stress-mediated inflammatory skin diseases.