Clinical profile of childhood-onset psoriasis and prevalence of HLA-Cw6: a hospital-based study from India

A Systematic Review of Follicular Psoriasis: A Unique but Under-Recognized Entity

Background

Follicular psoriasis (FP) is a rare and under-recognized subtype of psoriasis that affects hair follicles and can be frequently misdiagnosed due to its unique presentation.

Objective

We aimed to analyze the frequently reported clinical, histological, and dermatoscopic features of FP, as well as their treatment options.

Methods

We conducted a systematic review of the PubMed/MEDLINE database using the search terms "follicular" and "psoriasis." Fourteen studies were included yielding information on 44 patients (27 adults [61.4%] and 17 children [38.6%]).

Results

Adult FP showed a female predominance (M:F = 1:2.7), frequent involvement of lower extremities (81.5%), association with metabolic syndrome including diabetes mellitus (22.2%), and a predilection for skin of color (SOC:White = 8:1). On the contrary, juvenile FP revealed male predominance (M:F = 1:0.6), frequent involvement of the trunk (41.2%), and exclusive involvement in skin of color (SOC:White = 11:0). In addition to its unique presentation, FP tends to be misdiagnosed due to its low incidence of concomitant psoriasis (31.8%), and rare personal (18.2%) or family history (6.8%) of psoriasis. Reported histopathological features include keratotic plugging, follicular parakeratosis with or without neutrophils, psoriasiform acanthosis, hypogranulosis, and neutrophilic infiltration of follicular epithelium. Dermatoscopic findings include folliculocentric lesions with normal appearing terminal hairs, perifollicular white scale, and various vascular structures.

Conclusion

Once correctly diagnosed, patients with FP showed improvement or resolution of symptoms with various combinations of topical and systemic therapies. Understanding the demographic features and clinical presentations of FP can help address under-recognition of this clinical variant of psoriasis.

Disorders in Children

Pediatric dermatoses can present at birth or develop over time. When managing dermatology conditions in children, caregiver involvement is important. Patients may have lesions that need to be monitored or need assistance with therapeutic administration. The following section provides a subset of pediatric dermatoses and notable points for presentation in skin of color patients. Providers need to be able to recognize dermatology conditions in patients of varying skin tones and provide therapies that address the condition and any associated pigmentary alterations.

Recommendations for Management of Childhood Psoriasis

Childhood psoriasis is recognized as a potential multisystem disorder and hence it is imperative to optimize disease management to arrest progression, minimize psychological burden and evolution of metabolic syndrome. Clinical practice recommendations are necessary to assist practitioners in appropriate decision making based on available evidence. Owing to the lack of Indian recommendations on childhood psoriasis, the SIG Pediatric Dermatology under IADVL Academy undertook an evidence-based approach based on published literature on the topic, between January 2000 and July 2020 to frame the recommendations.

Limited clinical utility of HLA-Cw6 genotyping for outcome prediction in psoriasis patients under ustekinumab therapy: a monocentric, retrospective analysis

Purpose

Several studies have suggested that an HLA-Cw6+ allele can predict an improved outcome of treatment in psoriasis patients. The aim of the study was to assess whether the published association between HLA-Cw6 allele carriers and response to ustekinumab has the potential to impact treatment decisions.

Patients and methods

Differences in Psoriasis Activity and Severity Index 50, 75, and 90; Nail Psoriasis Severity Index; and Dermatology Life Quality Index at 16 weeks were evaluated between HLA-Cw6 allele carriers vs. non-carriers. Thirty patients with moderate-to-severe psoriasis under treatment with ustekinumab were included in our study.

Results

There was no difference between the two groups with respect to Psoriasis Activity and Severity Index 50, 75, and 90 or in terms of change in Nail Psoriasis Severity Index or Dermatology Life Quality Index.

Conclusion

In our retrospectively analyzed cohort, we could not detect the previously reported better response in HLA-Cw6+ vs. HLA-Cw6- patients.

The HLA-C*06 allele as a possible genetic predisposing factor to psoriasis in South Indian Tamils

Psoriasis is a multi-factorial heritable prototypical immune-mediated inflammatory disease, characterized by hyperproliferation of keratinocytes in the affected skin. There are no studies till date, to the best of our knowledge, about the association of HLA-C*06, the risk variant in the PSORS 1 susceptibility locus that confers the greatest risk for early onset of psoriasis, with the disease in South Indian Tamil patients with psoriasis. The present study was performed to determine the association of HLA-C*06 with psoriasis in the South Indian Tamil ethnic population. Three hundred and fifty-five cases of psoriasis and 360 healthy controls were included in this case-control study. Severity grading according to psoriasis area severity index (PASI) scoring was done in patients with psoriasis. PCR assays with sequence-specific primers (PCR-SSP) were used for specific detection of HLA-C*06. PCR with analysis of restriction fragment length polymorphism was used to distinguish between patients homozygous and heterozygous for HLA-C*06. We observed that those with the HLA-C*06-positive allele had a 3.5 times higher odds of having psoriasis compared to those without, [p < 0.0001, OR 3.5, 95 % CI (2.59-4.79)]. Among cases of psoriasis, it was noted that there was a significant association of HLA-C*06 positivity with female psoriatics [p = 0.006; OR 2.49 (1.28-4.87)] and early age of onset of psoriasis [p = 0.002; OR 2.04 (1.29-3.20)]. Our results suggest that the HLA-C*06 allele is positively associated with susceptibility to psoriasis, female gender and early onset of psoriasis in South Indian Tamils.