Atopic Dermatitis-like Genodermatosis: Disease Diagnosis and Management

A case of peeling skin syndrome type 1 with novel CDSN gene variation successfully treated with upadacitinib

Peeling skin syndrome type 1 (PSS1) is an autosomal recessive genodermatosis caused by the CDSN gene loss-of-function mutation and characterized by widespread superficial skin peeling and erythroderma with unbearable pruritus. Because of its ultra-rarity and unclear mechanism, this rare disease has no established treatment regimen. Herein, we reported a Chinese woman who presented with congenital generalized pruritic erythroderma and exfoliation, notable for significantly elevated IgE levels. The whole exome sequencing identified an unpublished homozygous variant (c.295C>T, p.Gln99*) in the CDSN gene, confirming the diagnosis of PSS1. Immunohistochemistry analysis of the affected skin confirmed the lack of corneodesmosin expression, revealed the overexpression of T helper 2 (Th2)-related cytokines harboring interleukin (IL) 4 and IL-13. After Janus kinase 1 (JAK1) inhibitor upadacitinib administration, both the patient's skin rashes and itching symptoms were significantly alleviated. Our work expanded the PSS1-related CDSN gene mutation spectrums, substantiated the hypothesis regarding the overexpression of Th2-related cytokines, and uncovered the important role of JAK1 underlying PSS1. JAK1 signaling may dominate the pathogenesis in PSS1 and represent a potential therapeutic target.

[A case of neonatal Netherton syndrome]

A male infant, aged 6 days, was admitted to the hospital due to respiratory distress and systemic desquamative rash after birth. The infant presented with erythema and desquamative rash, respiratory failure, recurrent infections, chronic diarrhea, hypernatremic dehydration, and growth retardation. Comprehensive treatment, including anti-infection therapy, intravenous immunoglobulin administration, and skin care, resulted in improvement of the rash, but recurrent infections persisted. Second-generation sequencing revealed a homozygous mutation in the SPINK5 gene, consistent with the pathogenic variation of Netherton syndrome. The family opted for palliative care, and the infant died at the age of 2 months after discharge. This report documents a case of Netherton syndrome caused by the SPINK5 gene mutation in the neonatal period, and highlights multidisciplinary diagnosis and therapy for this condition.

Diseases from the Spectrum of Dermatitis and Eczema: Can "Omics" Sciences Help with Better Systematics and More Accurate Differential Diagnosis?

Researchers active in the field of inflammatory skin diseases from the spectrum of dermatitis and eczema are well aware of a considerable overlap in the clinical pictures and proposed sets of diagnostic criteria for these diseases, which can hardly be overcome through the clinical or epidemiological research. In effect, patients are included in studies based on vague and overlapping criteria, while heterogeneous study populations may, in turn, lead to non-representative outcomes and continued confusion. In this narrative review, a systematics of diseases from the spectrum of dermatitis and eczema is proposed based on the origins of causative factors and the pathomechanisms involved. Difficulties in differentiating between these diseases are discussed, and the extent to which advances in the "omics" sciences might help to overcome them is considered. Of all the "omics" research in this field, more than 90% of the published papers were devoted to atopic dermatitis, with a striking underrepresentation of other diseases from the spectrum of dermatitis and eczema, conditions which collectively exceed the rates of atopic dermatitis by far. A greater "omics" research effort is urgently needed to tackle other dermatitides, like allergic, irritant and protein contact dermatitis, as well as radiation, seborrheic, stasis or autoimmune dermatitis. Atopic dermatitis findings should be validated not only against healthy donors but also other dermatitides. A clinic-oriented approach is proposed for future "omics" studies in the field of dermatitis and eczema.

[Holocarboxylase synthetase deficiency induced by HLCS gene mutations: a rare disease study]

A boy, aged 16 months, attended the hospital due to head and facial erythema for 15 months and vulva erythema for 10 months with aggravation for 5 days. The boy developed perioral and periocular erythema in the neonatal period and had erythema and papules with desquamation and erosion in the neck, armpit, and trigone of vulva in infancy. Blood gas analysis showed metabolic acidosis; the analysis of amino acid and acylcarnitine profiles for inherited metabolic diseases and the analysis of organic acid in urine suggested multiple carboxylase deficiency; genetic testing showed a homozygous mutation of c.1522C>T(p.R508W) in the HLCS gene. Finally the boy was diagnosed with holocarboxylase synthetase deficiency and achieved a good clinical outcome after oral biotin treatment. This article analyzes the clinical data of a child with holocarboxylase synthetase deficiency and summarizes the etiology, diagnosis, and treatment of this child, so as to provide ideas for clinicians to diagnose this rare disease.