Gastrointestinal Comorbidities Associated with Atopic Dermatitis-A Narrative Review

The current understanding of atopic dermatitis (AD) seems to be extending beyond a skin-confined condition frequently associated with allergic comorbidities, as in a number of epidemiological studies, the prevalence rate of a range of illnesses has been determined to be greater in patients with AD, or inversely. In most cases, the reasons for this are vague. A subset of these conditions are gastrointestinal disorders, including food sensitization (FS) and food allergy (FA), eosinophilic esophagitis (EoE) (it is of mixed background, both IgE-dependent and independent), food protein-induced enterocolitis syndrome (FPIES) (it exemplifies an IgE-independent food allergy), Crohn's disease (CD), colitis ulcerosa (CU), celiac disease, irritable bowel syndrome (IBS), and gastroesophageal reflux disease (GERD). In this review, we performed a comprehensive search of the literature using the PubMed database. We addressed the epidemiology of the increased co-occurrence of these diseases with AD and discussed potential causes for this subject. Multiple gastroenterological comorbidities appear to be more common in patients with AD, according to our review. The mechanisms that underlie this phenomenon are largely unknown, highlighting the need for further study in this field.

Potential Role of IL-37 in Atopic Dermatitis

Interleukin 37 (IL-37) is a recently discovered member of the IL-1 cytokine family that appears to have anti-inflammatory and immunosuppressive effects in various diseases. IL-37 acts as a dual-function cytokine, exerting its effect extracellularly by forming a complex with the receptors IL-18 α (IL-18Rα) and IL-1R8 and transmitting anti-inflammatory signals, as well as intracellularly by interacting with Smad3, entering the nucleus, and inhibiting the transcription of pro-inflammatory genes. Consequently, IL-37 is linked to IL-18, which plays a role in the pathogenesis of atopic dermatitis (AD), consistent with our studies. Some isoforms of IL-37 are expressed by keratinocytes, monocytes, and other skin immune cells. IL-37 has been found to modulate the skewed T helper 2 (Th2) inflammation that is fundamental to the pathogenesis of AD. This review provides an up-to-date summary of the function of IL-37 in modulating the immune system and analyses its potential role in the pathogenesis of AD. Moreover, it speculates on IL-37's hypothetical value as a therapeutic target in the treatment of AD.

Erythrodermic Presentation of Atopic Dermatitis in a Patient with Secondary Adrenal Insufficiency Caused by Oral Glucocorticosteroid Abuse

Dear Editor, A 41-year-old man presented to the Department of Dermatology for the first time due to an exacerbation of atopic dermatitis (AD) in the form of erythroderma. The patient had a history of atopic diseases, with being AD active from infancy. On clinical examination, generalized erythematous skin lesions causing acute pruritus and accompanied by severe skin exfoliation and dryness were present. On closer examination, the patient had a collection of signs and symptoms characterizing Cushing syndrome that included a round and full face (''moon face''), supraclavicular fat pads, and proximal muscle atrophy. The patient stated that AD had exacerbated six years earlier. He had received systemic treatment consisting of methotrexate followed by cyclosporine in another medical facility. However, both medications had proven ineffective and caused malaise. Only oral glucocorticosteroids had proven successful. The patient had been satisfied with the quick and observable effects, and, as he stated, he refrained from regular dermatological visits for six years. During that time, he consistently took 4 mg of methylprednisolone twice daily. Laboratory tests showed undetectably low levels of cortisol, triacylglycerols (TAG) at 288 mg/dL, and total cholesterol levels (CHC) of 81 mg/dL. Based on laboratory findings, clinical presentation, and histopathological evaluation of the skin biopsy, the diagnoses were secondary adrenal insufficiency caused by oral glucocorticosteroid abuse and AD in the form of erythroderma. The endocrinologist suggested a progressive reduction of the dose of methylprednisolone, starting at 2 mg twice daily. Total and sudden drug withdrawal was unacceptable, as it could cause an adrenal crisis. Methylprednisolone was eventually discontinued after being administered for 5 months while the blood levels of ACTH, cortisol, ionized sodium, and ionized potassium were monitored every 4 weeks. 25 mg of hydroxycortisol in divided doses was the actual treatment for adrenal insufficiency, with plans to also gradually reduce the dose. Since the commencement of endocrinological treatment, the dose was reduced to 15 mg after 5 months and to 10 mg after 7 months. Following an 8-month period, the patient began taking 10 mg as needed, usually a few times each month. Calcium carbonate in a dose of 1000 mg taken once daily before a meal for 5 months and vitamin D3 protected the patient from osteoporosis, another manifestation of Cushing syndrome. An initial dose of 4000 IU was prescribed. It is vital to emphasize that all dose adjustments in the endocrinological treatment of Cushing syndrome were a direct consequence of laboratory testing that was performed. In terms of erythrodermic AD management, the patient was treated with cyclosporin, which was once again ineffective. The patient was then prepared for the introduction of dupilumab. A 300 mg dose of the medication was subcutaneously administered every 2 weeks for over a year with positive outcomes, with an initial dose of 600 mg. The patient developed gynecomastia at the beginning of the treatment, initially categorized as another manifestation of Cushing syndrome. However, due to its unilateral nature, it was later identified a benign adverse event of dupilumab, as described in the literature (1). Due to a decline in effectiveness, the treatment was recently switched from dupilumab to baricitinib, with positive outcomes. Erythroderma, which the patient presented in our case, is an acute condition characterized by erythema and scaling that involves more than 90% of the skin's surface area (2,3). It can be potentially fatal due to electrolyte imbalance, fluid loss from capillary dilation, and significant heat dissipation (3). According to estimates, erythroderma is relatively rare, affecting approximately 1-2 patients for every 100,000 people per year, with AD comprising 8.7% of all cases of erythroderma (2,4). Despite growing therapeutic possibilities for AD, corticosteroids remain the drug of choice in severe exacerbations, including erythroderma, when we cannot afford to wait for the effects of therapy. Oral glucocorticosteroids can be an effective treatment for acute flares of AD (5). However, there is a lack of evidence for the long-term efficacy and safety of oral glucocorticosteroids in the treatment of AD (5). Reported side-effects include endocrine disturbances, gastric ulcers, cardiovascular disorders (arterial hypertension, atherosclerotic disease), osteoporosis, glaucoma, cataracts, and an increased risk of infections. Corticosteroids also have an undesired action on the skin that can result in steroid acne, skin atrophy, striae, telangiectasias, hypertrichosis, and impaired wound healing. The psychological adverse effects of steroid treatment can be quite severe and include depression and psychosis (6), The therapy should only be applied in the short-term, not exceeding one week, due to the occurrence of the abovementioned side-effects, which presented in as Cushing syndrome our patient (5). However, glucocorticoids are one of the most commonly used drugs in clinical dermatology practice, raising concerns about the risk of their misuse, which can lead to secondary adrenal insufficiency, among other complications (7). When no other treatment options are available, it should be noted that many of the side-effects of oral glucocorticosteroids can be mitigated through close monitoring and the implementation of appropriate preventive measures (7).

How to Understand Personalized Medicine in Atopic Dermatitis Nowadays?

Atopic dermatitis (AD) is a heterogeneous disease in terms of its phenotypical, barrier, and immunological presentation. Emerging therapies are undoubtedly contributing to a new chapter in the treatment of AD, bringing an excellent possibility of individualization, and thereby creating a tailored approach. The two most promising substance groups are biological drugs (dupilumab, tralokinumab, lebrikizumab, nemolizumab) and Janus kinase inhibitors (JAKis) (baricitinib, upadacitinib, and abrocitinib). The vision that certain well-defined phenotypes and endotypes, as well as personal preferences, may guide the future treatment of AD is both tempting and appealing, but not yet reality. The accessibility of new drugs such as biologics and small molecules has opened up the discussion regarding personalized medicine, referring to the complex nature of AD as well as the experiences from clinical trials and real-world evidence. We have now reached the point of creating new strategies and AD treatment goals by increasing the amount of new information concerning the efficacy and safety of new drugs. This article has reviewed the novel treatment options for AD in the light of the heterogeneity of this disease and proposes a broader vision on the strategy of personalized treatment of AD.