Pityriasis rubra pilaris: a review of diagnosis and treatment

Ophthalmic complication of pityriasis rubra pilaris

Pityriasis rubra pilaris (PRP) is a rare dermatological condition which may present with ocular manifestations. We report a case of recurrent cicatricial ectropion (CE) with topical beta-blocker use in the rare dermatological condition PRP. The patient underwent release of scar tissue, lateral tarsal strip and full-thickness supraclavicular skin graft for CE following immunosuppression with methotrexate for 3 months. Postoperatively, CE recurred, with skin graft shrinkage and resumption of periocular disease activity, 8 weeks following the introduction of topical timolol. The patient was referred for further immunosuppression and substitution of timolol before consideration for further surgery. PRP has a variety of potential ocular complications. Surgery has a high risk of recurrence and should be performed when the overall disease is quiescent and drugs, which could trigger reactivation, have been discontinued and/or substituted. Skin grafts should be oversized to off-set shrinkage.

Biologics for Treatment of Pityriasis Rubra Pilaris: A Literature Review

OBJECTIVE

To describe the published efficacy and adverse event rates associated with existing biologics for the treatment of pityriasis rubra pilaris (PRP).

DATA SOURCES

A literature review using the PubMed database (January 1990-July 2023) was conducted. Multiple search combinations were conducted using "pityriasis rubra pilaris" and various biologics as keywords to identify relevant articles.

STUDY SELECTION AND DATA EXTRACTION

Inclusion criteria included all study types that were published within the past 30 years in English and mentioned at least one biologic and PRP. A preliminary search yielded a total of 499 results. After screening using inclusion and exclusion criteria, 77 relevant articles (69 case reports, 5 case series, 2 clinical trials, and 1 retrospective analysis) were analyzed.

DATA SYNTHESIS

TNF-α inhibitors have been evaluated and are effective in treating PRP. However, recent treatment with anti-interleukin (IL)-17 and anti-IL-23 therapies such as ustekinumab, secukinumab, and ixekizumab are emerging as new treatment options with a mean improvement in PRP Area and Severity Index scores, change in severity of erythema, scaling, and thickness of PRP lesions. From initial clinical trials, secukinumab and ixekizumab are promising treatment options for achieving remission.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review compares the efficacy for numerous biologics and a discussion to guide clinicians on benefits and risks in choosing a biologic for PRP patients.

CONCLUSIONS

Biologics may be a favourable treatment option leading to greater patient adherence due to reduced dosing frequencies, improvement in quality of life, and reduction in frequency and severity of flares.

Updates on Pityriasis Rubra Pilaris: A Scoping Review

Pityriasis rubra pilaris (PRP) is a rare, inflammatory papulosquamous skin disease with unknown exact etiology. Historically, PRP has been challenging to diagnose, especially during the acute phase, and to treat, due to its unclear pathogenesis. To better inform clinical practice, a literature review was conducted employing a broad search strategy to capture PRP-related published studies between January 1, 2012 to October 31, 2022. Two hundred twenty-one studies were identified, which were categorized into 9 themes: (1) potential causes and triggering factors, (2) comorbidities, (3) diagnostic difficulties, (4) genetics, (5) clinical manifestations and laboratory values, (6) treatment, (7) treatment-related adverse events, (8) quality of life, and (9) other. COVID-19 infection, COVID-19 vaccination, and malignancy were the most commonly reported potential triggering factors. Misdiagnosis is very common during the early acute stages. Pathogenesis and genetic studies have further implicated caspase recruitment domain family member 14 (CARD14) mutations in the development of familial PRP (Type V) and have underlined the overlap between psoriasis and PRP. To date, there are currently no specific and validated scoring systems or tools to assess the severity of PRP. While large, randomized trials are still lacking, biologic agents remain the most effective therapy.

Successful Treatment of Pityriasis Rubra Pilaris with Risankizumab in Children

Pityriasis rubra pilaris (PRP) is a rare inflammatory skin disease that affects men and women of all ages, including children. PRP is characterized by follicular and palmoplantar hyperkeratosis and salmon-colored scaling plaques. The exact pathogenesis of PRP is still unknown; most PRP cases are acquired, but some cases may show a familial occurrence, often associated with a mutation in the CARD14 gene. Due to the rarity of PRP, treatment recommendations are based mainly on case reports, small case series and expert opinions and still represent a major therapeutic challenge, especially in children. A growing number of reports on treatment with biologicals, particularly anti-TNFα, has been published. However, an involvement of the IL-23/Th17 axis in both psoriasis and PRP pathogenesis may suggest that this pathway may be a potential therapeutic target. Here, we present three pediatric patients with PRP successfully treated with risankizumab. All patients exhibited a severe course of PRP and lack of response to conventional therapy, including acitretin, cyclosporine and phototherapy. A single dose of 75 mg risankizumab resulted in almost complete clearance of skin lesions in case 1 and 2 at week 4. In patient 3, clear skin was achieved after the second administration of risankizumab (150 mg). All patients continue the treatment with risankizumab, and no adverse effects have been reported up to the present time. Our study demonstrates that risankizumab, an IL-23 blocker, shows good efficacy and safety among pediatric patients with PRP.

A Rare Post-infectious Rash: Pityriasis Rubra Pilaris After COVID-19 Infection

Pityriasis rubra pilaris (PRP) is a rare papulosquamous skin disorder that often presents with erythematous follicular-based hyperkeratotic papules that can become confluent and lead to erythroderma and electrolyte and thermoregulatory imbalances resulting from increased tissue perfusion and skin barrier breakdown. Due to this condition being uncommon, many specialties outside of dermatology are unfamiliar with this entity which poses unique diagnostic and management challenges. This case report involves a 55-year-old woman who presented to the emergency room with erythroderma secondary to PRP. It highlights the relevance of PRP in the context of in-hospital management by presenting the patient's clinical profile, diagnostic workup, and treatment plan. By emphasizing the distinctive clinical features and natural course of the disease, this report aims to enhance the understanding of this uncommon inflammatory skin condition.

Secukinumab for the treatment of adult-onset pityriasis rubra pilaris: a single-arm clinical trial with transcriptomic analysis

BACKGROUND

The pathogenesis of pityriasis rubra pilaris (PRP) is not completely understood, but interleukin (IL)-17 has been shown to play a critical role. There are no reliable immunomodulatory agents to treat PRP. We conducted an open-label, single-arm clinical trial of secukinumab, a monoclonal antibody that inhibits IL-17A, for the treatment of PRP.

OBJECTIVES

To evaluate the clinical efficacy of secukinumab and define the transcriptomic landscape of PRP and its response to IL-17A blockade.

METHODS

Twelve patients with PRP were recruited for an open-label trial of secukinumab. Patients received a 24-week course of secukinumab. The primary endpoint was a ≥ 75% reduction in Psoriasis Area and Severity Index (PASI 75) from baseline to week 28. Secondary endpoints included PASI 90, change in Physician's Global Assessment (PGA), and change in Dermatology Life Quality Index (DLQI). RNA sequencing was performed on lesional and nonlesional skin biopsies obtained at baseline and week 2. Sample groups were compared to identify differential gene expression and pathway enrichment. This trial was registered with ClinicalTrials.gov: 'Cosentyx (secukinumab) for the treatment of adult onset pityriasis rubra pilaris' - NCT03342573.

RESULTS

At week 28, six of 11 patients (55%) achieved PASI 75, and three patients (27%) achieved PASI 90. PGA (P = 0.008) and DLQI scores (P = 0.010) showed significant improvement with treatment. No serious treatment-related adverse events were encountered. Treatment with secukinumab normalized transcriptional differences between lesional and nonlesional skin. Transcriptomic data from nonresponsive patients suggest that overactivity of innate immune pathways may be driving resistance to secukinumab.

CONCLUSIONS

Secukinumab appears to be an effective treatment for PRP and warrants further investigation. PRP is a transcriptionally heterogeneous disease, reflecting its variable response to therapy. Agents targeting other IL-17 isoforms and innate immune mediators should be considered for future clinical trials. What is already known about this topic? The pathogenesis of pityriasis rubra pilaris is incompletely understood. Successful treatment has been reported with a variety of immunomodulatory agents, but disease is often refractory to therapy. Interleukin (IL)-17 is thought to drive keratinocyte proliferation and vascular dysfunction in this disease. A previous trial demonstrated efficacy of the anti-IL-17A drug ixekizumab for pityriasis rubra pilaris. What does this study add? Herein we describe the findings of a clinical trial of secukinumab, an anti-IL-17A monoclonal antibody, for the treatment of pityriasis rubra pilaris. Secukinumab was effective in treating pityriasis rubra pilaris. Our transcriptomic data give new insight into the expressional changes that occur in response to secukinumab and suggest mechanisms of treatment resistance.

Beyond plaque psoriasis - pathogenesis and treatment of other psoriasis phenotypes

PURPOSE OF REVIEW

Psoriasis vulgaris is the commonest presentation of psoriatic disease, but morphologic variants such as pustular psoriasis (PP) and a closely related disease, pityriasis rubra pilaris (PRP), have been known for a long time, have been associated with rheumatologic manifestations indistinguishable from psoriatic arthritis (PsA) that may go unrecognized, and often represent a therapeutic conundrum. There is recent evidence that underlying genetic and pathogenetic differences may provide the basis for newer therapeutic approaches.

RECENT FINDINGS

This narrative review highlights the clinical, genetic and pathogenetic characteristics of PP and PRP, their association with PsA and recent developments in their treatment, especially with biologic agents targeting IL-36 and other cytokines of pathogenic relevance.

SUMMARY

The clinical manifestations of PP and PRP are less well known to rheumatologists than those of psoriasis, and recent advances in our insight on their pathogenesis may eventually overcome the therapeutic difficulties faced by dermatologists and rheumatologists in the management of these diseases and their rheumatologic manifestations.

A case of classic adult pityriasis rubra pilaris successfully treated with a combination of acitretin and ustekinumab: A case report

Classic adult pityriasis rubra pilaris is a severe papulosquamous disease that tends to resolve in 3-5 years but can have a devastating impact on patients while active. It shares features with psoriasis, but treatment remains largely empiric, based on case reports and series. The condition is often refractory to treatment, especially initially, with topical corticosteroids and oral acitretin the more commonly employed agents. Relatively high doses of acitretin are needed for adequate response, and adverse events often limit adherence. Given the similarity to psoriasis, biologic agents approved for psoriasis have been used with good effect in classic adult pityriasis rubra pilaris and show better tolerance than other agents. In this report, we describe the successful use of a combination of acitretin and ustekinumab in a case of classic adult pityriasis rubra pilaris.

Deleterious side effects of nutritional supplements

Vitamin and mineral supplement consumption is widespread. They are taken for a variety of conditions, including dermatologic disorders. Although consumers often assume these supplements are safe, excessive consumption of supplements may have deleterious effects. Such vitamin supplements include vitamin A, niacin, biotin, vitamin D, and vitamin E, and specific mineral supplements include zinc, copper, and iron. These supplements may have a number of potential adverse effects.

Topographic Differential Diagnosis of Chronic Plaque Psoriasis: Challenges and Tricks

BACKGROUND

Psoriasis is an inflammatory skin disease presenting with erythematous and desquamative plaques with sharply demarcated margins, usually localized on extensor surface areas.

OBJECTIVE

To describe the common differential diagnosis of plaque psoriasis classified according to its topography in the scalp, trunk, extremities, folds (i.e., inverse), genital, palmoplantar, nail, and erythrodermic psoriasis.

METHODS

A narrative review based on an electronic database was performed including reviews and original articles published until 1 September 2020, assessing the clinical presentations and differential diagnosis for psoriasis.

RESULTS

Several differential diagnoses could be considered with other inflammatory, infectious, and/or neoplastic disorders. Topographical differential diagnosis may include seborrheic dermatitis, tinea capitis, lichen planopilaris in the scalp; lupus erythematosus, dermatomyositis, cutaneous T-cell lymphomas, atopic dermatitis, syphilis, tinea corporis, pityriasis rubra pilaris in the trunk and arms; infectious intertrigo in the inguinal and intergluteal folds and eczema and palmoplantar keratoderma in the palms and soles.

CONCLUSIONS

Diagnosis of psoriasis is usually straightforward but may at times be difficult and challenging. Skin cultures for dermatophytes and/or skin biopsy for histological examination could be required for diagnostic confirmation of plaque psoriasis.

Pityriasis rubra pilaris type 6: A case report in an AIDS patient

A 24-year-old woman, known to be human immunodeficiency virus positive for 6 years, presented with an itchy rash on the body. She had dull erythematous to hyperpigmented scaly plaques over the body, with extensor predominance. Inflammatory papules and nodules were noted on the face. Follicular hyperkeratotic papules were seen on the shins, giving a “nutmeg grater” feel. All her nails were dystrophic. Histopathology was consistent with the clinical diagnosis of pityriasis rubra pilaris. CD4 counts had dropped to 192 cells/μl, so she was started on antiretroviral therapy along with acitretin to which she responded well within 2 months.

A Case of Meningococcal and HSV-2 Meningitis in a Patient Being Treated with Ustekinumab for Pityriasis Rubra Pilaris

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous dermatosis affecting both adults and children. Six subtypes of PRP have been described. Recently, the management of PRP with biologic immunosuppressive agents regularly used in psoriasis has been supported by several case reports and series. Ustekinumab is an anti-IL12/23 IgG1 kappa human monoclonal antibody. It has been approved for the treatment of Crohn’s disease, plaque psoriasis, psoriatic arthritis and ulcerative colitis. It has also been reported to be effective as an off-label treatment for PRP. Current data are equivocal regarding infectious disease risk with ustekinumab administration. We describe a case of meningococcal and HSV-2 infection of the central nervous system in a patient being treated with ustekinumab for PRP.

Erythrodermic psoriasis secondary to systemic corticosteroids

Erythroderma is an uncommon, potentially life-threatening condition, which has many causes, including uncontrolled psoriasis. We present a 58-year-old woman with psoriasis who, after an abrupt discontinuation of systemic corticosteroids, developed erythrodermic psoriasis with extensive body surface involvement requiring hospital admission. Erythrodermic psoriasis requires a high index of suspicion to diagnose it in a timely fashion and treat it to prevent complications.

Pityriasis rubra pilaris-like graft-vs-host disease following allogeneic stem cell transplant in two patients

Chronic cutaneous graft-vs-host disease (GVHD) has several atypical variants. We describe two cases of GVHD with clinical and histopathologic features of pityriasis rubra pilaris (PRP), which responded to additional immunosuppression. Recognition of this newly described PRP-like clinical presentation of GVHD may prompt early consideration of additional steroid-sparing therapies.

Acantholytic pityriasis rubra pilaris associated with topical use of imiquimod 5%: case report and literature review

Topical use of immune response modifiers, such as imiquimod, has increased in dermatology. Although its topical use is well tolerated, it may be associated with exacerbations of generalized cutaneous inflammatory diseases, possibly through the systemic circulation of pro-inflammatory cytokines. This report describes a case of development of pityriasis rubra pilaris, a rare erythematous-papulosquamous dermatosis, in a woman aged 60 years during treatment with imiquimod 5% cream for actinic keratosis. It evolved with erythrodermic conditions and palmoplantar keratoderma, presenting progressive clinical resolution after the introduction of methotrexate. The authors emphasize the importance of recognizing possible systemic reactions associated with the topical use of imiquimod.

Use of Biologics in Pityriasis Rubra Pilaris Refractory to First-Line Systemic Therapy: A Systematic Review [Formula: see text]

Pityriasis rubra pilaris (PRP) is an uncommon, inflammatory, papulosquamous skin disease. Treatment of PRP is challenging as the disease is often refractory to conventional therapies, such as retinoids and methotrexate. There has been an increasing number of studies reporting the successful use of biologic therapy in patients with PRP; however, the data on the efficacy and safety are limited. Our objective was to evaluate the existing evidence for utilizing biologics, whether alone or in combination with established systemic therapies, in patients with treatment-resistant PRP. We systematically reviewed evidence within Medline and Pubmed databases between January 1, 2000, to March 31, 2019. Articles consisted of patients diagnosed with PRP who have failed to respond sufficiently to first-line systemic therapies, or who had comorbidities that precluded their use. In total, 363 unique articles were identified, 56 of which were considered relevant to the clinical question. Of the 56 articles highlighted, 35 met the inclusion criteria and were limited to case series and case studies. Therapy with biologics was found to be successful for both monotherapy (81.1% [27/33]) and when used in combination with existing systemic therapies (87.5% [14/16]). The existing evidence suggests that biologics may be regarded as a tool for PRP treatment alone or in combination therapy with existing treatments, although large-scale randomized clinical trials are necessary to better assess their efficacy and safety.

The management and genetic background of pityriasis rubra pilaris: a single-centre experience

BACKGROUND

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory dermatosis with multifactorial aetiology. It is known that particular caspase recruitment domain family member 14 (CARD14) gene mutations are associated with familial PRP and certain forms of psoriasis. Additionally, few data are available about the role of CARD14 gene variants in sporadic PRP. The clinical picture is variable for the different types of PRP, therefore choosing the adequate treatment is often difficult, furthermore there are no specific guidelines for therapy.

OBJECTIVE

Our aim was to survey the efficacy of the applied therapies and to screen the CARD14 gene variants in our PRP patients.

METHODS

In this retrospective study, patients diagnosed with PRP between 2006 and 2016 at our clinic were involved. Besides the follow-up study of the treatments, the genetic analysis of CARD14 gene was performed.

RESULTS

We analysed 19 patients, among whom 17 were diagnosed with type I, one with type III, and one with type V PRP. The majority of the patients were successfully treated with acitretin in combination with systemic corticosteroids, and the remaining patients were treated with other systemic therapies with diverse effects. The genetic screening of CARD14 gene revealed two previously described mutations (rs114688446, rs117918077) and six polymorphisms (rs28674001, rs2066964, rs34367357, rs11653893, rs11652075, rs2289541). Ten of 19 patients carried different CARD14 genetic variants either alone or in combination.

CONCLUSION

Based on our experience, we propose that acitretin and an initial combination of short-term systemic corticosteroid therapy could be a successful treatment option for PRP. Although we identified several CARD14 variants in almost half of our cases, we did not find a correlation between the therapeutic response and the genetic background. Our data support the previous observation that CARD14 genetic variants are not specific to PRP, although they may indicate chronic inflammation.

Systemic therapies of pityriasis rubra pilaris: a systematic review

Pityriasis rubra pilaris (PRP) is a rare papulosquamous disorder. Treatment is challenging; the armamentarium consists of topical corticosteroids, phototherapy, classic systemic treatments such as retinoids or immunosuppressive drugs, and most recently biologicals. However, the relative effectiveness of therapies is unclear. Our objective was to review the published literature on systemic treatment of PRP. A systematic review was conducted on PubMed and the Cochrane Library up to 5 September 2017. Studies evaluating any systemic treatments of PRP (except for historical treatments) were included. Overall, 182 studies met the predefined inclusion criteria, and reported on 475 patients and 652 courses of treatment. 42.0 % (225/514) of all patients treated with retinoids achieved an excellent response (isotretinoin: 61.1 % [102/167], etretinate: 47 % [54/115], and acitretin: 24.7 % [43/174]) compared to an excellent response rate of 33.1 % (53/160) with methotrexate. Therapy with biologicals was successful in 51.0 % of patients (71/133) (ustekinumab: 62.5 % [10/16], infliximab: 57.1 % [28/49], etanercept: 53.3 % [16/30], and adalimumab: 46.4 % [13/28]). This review balances effectiveness, side effects, experience, and drug costs in order to suggest a treatment regimen starting with isotretinoin as first-line, methotrexate as second-line and biologicals as third-line treatment for this difficult-to-treat dermatosis.

Erythroderma

Erythroderma, often described as generalized exfoliative dermatitis, is a condition in which erythema involves greater than 90% of the body surface, often as a result of an underlying inflammatory skin condition, which can result in a variety of systemic manifestations and potentially lead to life-threatening complications.

Nuclear Factor κB Activation in a Type V Pityriasis Rubra Pilaris Patient Harboring Multiple CARD14 Variants

Pityriasis rubra pilaris (PRP) is a rare papulosquamous skin disorder, which is phenotypically related to psoriasis. Some familial PRP cases show autosomal dominant inheritance due to CARD14 mutations leading to increased nuclear factor κB (NFκB) activation. Moreover, CARD14 polymorphisms have also been implicated in sporadic PRP. A Hungarian PRP patient with childhood onset disease showing worsening of the symptoms in adulthood with poor therapeutic response underwent genetic screening for the CARD14 gene, revealing four genetic variants (rs117918077, rs2066964, rs28674001, and rs11652075). To confirm that the identified genetic variants would result in altered NFκB activity in the patient, functional studies were carried out. Immunofluorescent staining of the NFκB p65 subunit and NFκB-luciferase reporter assay demonstrated significantly increased NFκB activity in skin samples and keratinocytes from the PRP patient compared to healthy samples. Characterization of the cytokine profile of the keratinocytes and peripheral blood mononuclear cells demonstrated that the higher NFκB activation in PRP cells induces enhanced responses to inflammatory stimuli. These higher inflammatory reactions could not be explained solely by the observed CARD14 or other inflammation-related gene variants (determined by whole exome sequencing). Thus our study indicates the importance of investigations on other genetic factors related to PRP and their further functional characterization to bring us closer to the understanding of cellular and molecular background of disease pathogenesis.

A Review on Pityriasis Rubra Pilaris

Pityriasis rubra pilaris (PRP) is an idiopathic, papulosquamous inflammatory dermatosis. It is characterized by hyperkeratotic follicular papules coalescing into orange-red scaly plaques, islands of sparing, and palmoplantar keratoderma. PRP can be subdivided into six clinical subtypes according to Griffiths' classification, based on age of onset, disease extent, prognosis, and other associated features. The sixth subtype of PRP occurs in individuals affected by HIV infection, and retroviral screening in all de novo cases of PRP is advised. Other reported associations include various infections, autoimmunity, drugs, and malignancies, although the true significance of these is still unclear. The genetic basis for familial cases, most commonly categorized under the fifth subtype, has been mapped to gain of function mutations in the caspase recruitment domain family, member 14 (CARD14) gene. Treatment of PRP remains a challenge to this day due to a paucity of high-quality evidence. Therapeutic regimens have been guided mostly by case reports and case series, with the mainstay of treatment being oral retinoids. Recently, biologics have emerged as a promising treatment for PRP. We present a review of the clinicopathologic features, pathogenesis, associated disorders, and treatment of PRP, with an emphasis and critical appraisal of the existing literature on the latter.

Pityriasis rubra pilaris-like erythroderma secondary to phosphoinositide 3-kinase inhibition

BACKGROUND

Phosphoinositide 3-kinase (PI3K) inhibitors are a class of small-molecule inhibitors approved for the treatment of certain leukaemias and lymphomas. Their dermatological adverse event profile is poorly described.

AIM

To characterize a rare cutaneous adverse event from PI3K inhibitors in order to help dermatologists and oncologists identify and effectively manage such eruptions.

METHODS

This was a retrospective analysis of patients receiving PI3K inhibitors referred to the Skin Toxicities Program in The Center for Cutaneous Oncology.

RESULTS

Three patients on PI3K inhibitors for treatment of malignancy developed diffuse erythroderma and keratoderma. Clinical and histopathological findings were consistent with pityriasis rubra pilaris (PRP)-like reactions. All patients improved with topical and oral corticosteroids, oral acitretin, and drug discontinuation.

CONCLUSIONS

PRP-like cutaneous eruptions may develop secondary to PI3K inhibition. Early dermatological evaluation of cutaneous toxicities to PI3K inhibitors as well as rapid initiation of disease-specific treatments may help keep patients on life-prolonging anti-cancer therapies.

Recurrent Pityriasis Rubra Pilaris: A Case Report

Pityriasis rubra pilaris (PRP) is an uncommon papulosquamous dermatosis characterized by follicular, erythematous, hyperkeratotic papules coalescing to salmon-coloured plaques with islands of sparing. The disease tends to be self-limited and resolves spontaneously after a few years. In some cases, the disease is persistent. However, recurrence of this disease has rarely been described. An 8-year-old male was diagnosed with type III (classic juvenile) PRP. He was treated with acitretin, and his skin was clear after 6 months. He remained disease free for 6 years. At 14 years old, he was diagnosed again with type III PRP. His cutaneous manifestations were highly similar to his initial presentation. He was treated with acitretin and methotrexate concurrently and achieved skin clearance. Recurrence of type III PRP is possible although rarely described in the literature. Acitretin ± methotrexate therapy is effective at achieving skin clearance.

Biologics for pityriasis rubra pilaris treatment: A review of the literature

Pityriasis rubra pilaris (PRP) is a rare inflammatory papulosquamous skin disease that is often refractory to conventional therapies. The off-label use of biologics, such as anti-tumor necrosis factor, anti-interleukin (IL) 12/IL-23, and anti-IL-17 agents, has been proven successful in the past 2 decades for PRP treatment. Our aim was to analyse the literature for the use of biologics in PRP treatment. We conducted a review by performing PubMed and ClinicalTrials.gov searches. Sixty-eight articles met our selection criteria and are herein discussed. Out of 86 PRP patients, the vast majority were treated with anti-tumor necrosis factor, anti-IL-12/IL-23, or anti-IL-17 biologics, either alone or in combination therapy. A marked-to-complete response was observed in 50%-78%, a partial response in 11%-25%, and no or poor response in 11%-25%. This review has several limitations, including small sample sizes and the lack of shared study design criteria. In some instances, PRP might have resolved spontaneously. Further, the presence of concomitant therapy or the lack of detailed data on previous treatments, makes it difficult to strictly define a therapeutic role per se of specific biologics in PRP. This review shows that biologics may be regarded as a tool for PRP treatment alone or in combination therapy although clinical trials are needed to better assess their efficacy and safety.

HIV-Associated Psoriasis

Human immunodeficiency virus (HIV) prevalence is increasing worldwide as people on antiretroviral therapy are living longer. These patients are often susceptible to debilitating inflammatory disorders that are frequently refractory to standard treatment. Psoriasis is a systemic inflammatory disorder, associated with both physical and psychological burden, and can be the presenting feature of HIV infection. In this population, psoriasis tends to be more severe, to have atypical presentations and higher failure rates with the usual prescribed treatments. Management of moderate and severe HIV-associated psoriasis is challenging. Systemic conventional and biologic agents may be considered, but patients should be carefully followed up for potential adverse events, like opportunist infections, and regular monitoring of CD4 counts and HIV viral loads.

[Pityriasis rubra pilaris]

Pityriasis rubra pilaris is a rare heterogeneous dermatosis associating three clinical signs to different degrees: follicular corneal papules, reddish-orange palmoplantar keratoderma and erythematosquamous lesions that may in some cases be very extensive, interspersed with patches of healthy skin. The aetiology is unclear, and in most cases, the trigger factors consist of trauma or infection, probably in subjects with an existing predisposition. In other cases, the condition is associated with immunological disorders or, in familial cases, genetic keratinisation abnormalities similar to ichthyosis. Given the widely varying signs, several classifications have been proposed, based on clinical criteria and outcomes. The outcome varies in accordance with the clinical forms involved. Therapeutic approaches are poorly qualified and there have been no clinical trials due to the rarity of the disease. However, the best results appear to have been obtained using oral retinoids, with second-line therapy comprising methotrexate and cyclosporine. The landscape of therapeutic strategy seems to be changing with the advent of new anti-tumour necrosis factor and anti-interleukin-12/23 antibodies.

Methotrexate treatment in a case of juvenile pityriasis rubra pilaris

An 8-year-old boy who was initially diagnosed with plaque psoriasis failed management with topical therapies and skin biopsy confirmed the suspected diagnosis of juvenile pityriasis rubra pilaris (PRP). Pityriasis rubra pilaris is a rare inflammatory disorder of the skin characterized by follicular keratotic papules coalescing into plaques, along with palmoplantar keratoderma. Treatment modalities include topical and systemic therapies, although previous studies have not shown much benefit with methotrexate in children. We present a case in which methotrexate led to significant improvement of the skin findings in a child with type IV juvenile pityriasis rubra pilaris.

Erythrodermic Psoriasis in a Man with Monoclonal B-cell Lymphocytosis

Erythroderma is characterized by erythema involving greater than 90% of the body surface area and may be caused by several etiologies, including erythrodermic psoriasis. Psoriasis is an autoimmune skin and systemic condition characterized by erythematous and scaly plaques. Monoclonal B-cell lymphocytosis is an asymptomatic hematological disorder diagnosed by elevated, small, clonal B-cell counts in the peripheral blood. The characteristics of a 71-year-old man with new onset of erythrodermic psoriasis and concurrent monoclonal B-cell lymphocytosis are presented. The simultaneous development of these two conditions raises the possibility that they may share a related pathogenesis.