A latent class analysis (LCA) found that the degree of chronic hand eczema may be helpful in identifying specific phenotypes of this condition, according to study results published in the Journal of the European Academy of Dermatology and Venereology.
In the study, investigators enrolled a total of 71 consecutive well-characterized patients with a chronic hand eczema diagnosis of ≥6 months. They conducted a personal and family medical history and assessed clinical severity of the condition using the modified Total Lesion Symptom Score and patch testing.
The researchers performed 2 independent LCAs integrating clinical severity, total Immunoglobulin E plasma level, transepidermal water loss, hydration index, interleukin-8 lesional skin level, Staphylococcus (aureus and epidermidis) colonization, filaggrin genotype, and expression of genes associated with the cornified envelope formation, encoding anti-microbial peptides and chemokines, filaggrin degradation and the natural moisturizing factor synthesis, or tight junctions’ structure and the desquamation process.
The majority of patients (81.7%) had eczema that affected both hands, with dry eczema with fissures having the highest clinical presentation frequency in 60.6%. Overall, the median duration of disease was 3 years (interquartile range, 1.1-16.1). The first LCA categorized patients into 2 classes of hand eczema (class A [49%] and class B [51%]).
Patients in class B had a higher modified Total Lesion Symptom Score, high S epidermidis and S aureus densities, and IL-8 on skin surface compared with patients in class A. In the second LCA, researchers categorized patients into class C (54%) and class D (46%). Patients in class D had a higher probability of transepidermal water loss and low levels of transcription of genes for proteins involved in natural moisturizing factors of the skin compared with patients in class C.
Study limitations include the small sample size and the performance of the gene expression study on only the upper epidermis layers.
According to their findings, the researchers concluded that an LCA “approach suggests that the degree of skin barrier dysfunction is the most important parameter to discriminate” patients with chronic hand eczema “whatever the etiological factors.”
Tauber M, Bérard E, Lourari S, et al. Latent class analysis categorises chronic hand eczema patients according to skin barrier impairment [published online November 17, 2019]. J Eur Acad Dermatol Venereol. doi:10.1111/jdv.16083