Alles wat u moet weten over Pityriasis Rubra Pilaris

Rethinking pityriasis rubra pilaris as a paraneoplastic syndrome: Two cases of pityriasis rubra pilaris with concomitant underlying malignancy

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Pityriasis rubra pilaris (PRP) is a chronic papulosquamous dermatosis characterized by orange-salmon–colored plaques with scales, islands of sparing, palmoplantar keratoderma, and keratotic follicular papules.1, 2 There are 6 categories of PRP as follows: (1) classic adult type, (2) atypical adult type, (3) classic juvenile type, (4) circumscribed juvenile type, (5) atypical juvenile type, and (6) HIV-associated PRP. 1 , 2 Currently, PRP is not considered to be a paraneoplastic syndrome due to limited case numbers. We present 2 cases of paraneoplastic PRP, review the literature, and reevaluate the discussion of PRP as a paraneoplastic syndrome.

Clinical forms and patterns

One of the most important clinical aspects of psoriasis is represented by the evolution as chronic relapsing episodes of remission and exacerbation. The most characteristic form of psoriasis is psoriasis vulgaris, presented as well delimitated individual erythematous lesions, with a thick and silvery scale, sometimes diagnosed by Auspitz sign, in which forced elimination of scales leads to minimal areas of bleeding [1]. Psoriasis vulgaris has a tropism for extensors, due to Koebner (isomorphic) phenomenon (trauma related lesions), while inverse psoriasis involves the flexures, presenting shiny erythema and minor scales [1]. The involvement of the nail leads to thickening and yellow-brown discoloration of the nail plate, known as onychodystrophy. This lesion is rarely located in the mucosa, especially on the glans penis, this localization being related to uncircumcision [1]. Another form is guttate (small) psoriasis, as an acute variant mainly in children, manifested by erupted lesions on proximal extremities and trunk, as an immune-mediated reaction between streptococcal M protein and human cutaneous tissues [1]. Erythrodermic psoriasis is manifested as generalized erythema, with important scale shedding and skin vascular dilatation preventing thermoregulation [1].

Reiter’s syndrome tend to affect young men, being highlighted by the specific triad of urethritis (with negative urethral cultures), arthritis, and conjunctivitis, which is complete only in one-third of patients. Specific lesions comprise mucocutaneous forms as keratoderma blenorrhagicum (psoriasiform eruption of the palms and soles), balanitis circinata (penile eruption), geographic tongue (ulcerative or erosive oral lesions), and subungual pustules with oncholysis [1]. Moreover, it has been associated with different gut and genital infectious agents, like: Shigella flexneri, Yersinia enterocolitica, Campylobacter jejuni, Chlamydia trachomatis, Ureaplasma urealyticum, and Mycoplasma [3].

Histopathological features

In this regard, there are used hematoxylin-eosin (H&E) staining, as well as acid periodic-Schiff reactive (PAS) staining, for the assessment of the basement membrane and the presence of fungal organisms. Other special stainings are sometimes necessary for the diagnosis of inflammatory dermatoses, such as: fibrin staining (Martius-Scarlet blue), acid mucin staining (colloidal iron Hale’s), iron staining (Prussian blue), mast cells staining (toluidine blue), melanin staining (Fontana Masson), elastin staining (Orcein), demonstration of calcium deposits (Von Kossa staining), amyloid staining (Congo red). Bacteria and fungi can also be evidentiated with Gram and Gomori stainings [21]. Immunohistochemistry and electron microscopy have a limited value in diagnosis of inflammatory psoriasiform dermatoses (unless they are important for differential diagnostic with other related conditions), while immunofluorescence is specific for vesiculobullous diseases [21].

Psoriasis with extensive hyperkeratosis with horizontally confluent parakeratosis (HE, x50)

Introduction

Inflammatory dermatoses comprise a large spectrum of clinico-morphological entities, the most common, known as major forms of psoriasiform dermatoses, being: psoriasis, pustular psoriasis, Reiter’s syndrome, pityriasis rubra pilaris, lichen simplex chronicus, and large-plaque parapsoriasis (parapsoriasis en grandes plaques). Psoriasis represents the prototype of this category, which can be defined according to inflammation and epidermal changes, the histological mark being regular elongation of rete ridges, due to greater keratinocyte proliferation, partially or totally involving the epidermis [1]. Although the general histological features are shared by most of the inflammatory dermatoses, there are specific microscopical aspects which are pathognomonic for each major form of this disease, which highlight the differences between all inflammatory dermatoses in terms of clinical appearance, pathogenesis and histopathological characteristics related to the quality of scales and the distribution and composition of the inflammatory infiltrate [1].

The aim of our study is to review the main pathogenetic mechanisms and the clinico-histopathological diagnostic features of major form of psoriasiform dermatoses and to emphasize the characteristic microscopical differences between them, for a better approach of the diagnosis, as an important key for clinical and therapeutic management.

References

1. Fekete G.L., Boda D., Căruntu C., Fekete L. Paraneoplastic pityriasis rubra pilaris in association with prostate carcinoma: a case report and literature review. Exp Ther Med. 2019, 18 :5052–5055. doi: 10.3892/etm.2019.8169. [PMC free article] [PubMed] [CrossRef] [Google Scholar]

2. Griffiths W.A. Pityriasis rubra pilaris. Clin Exp Dermatol. 1980, 5 :105–112. doi: 10.1111/j.1365-2230.1980.tb01676.x. [PubMed] [CrossRef] [Google Scholar]

4. Batinac T., Kujundzić M., Peternel S., Cabrijan L., Troselj-Vukić B., Petranović D. Pityriasis rubra pilaris in association with laryngeal carcinoma. Clin Exp Dermatol. 2009, 34 :e917–e919. doi: 10.1111/j.1365-2230.2009.03701.x. [PubMed] [CrossRef] [Google Scholar]

5. Vance P., Wyles S., Alavi A. Paraneoplastic pityriasis rubra pilaris preceding leukemia. Adv Skin Wound Care. 2022, 35 :1–4. doi: 10.1097/01.ASW.0000826828.53117.8c. [PubMed] [CrossRef] [Google Scholar]

6. Lamberg O., Cao S., Sabater-Geib S., Lowe L., Elder J. A case of recurrent and paraneoplastic pityriasis rubra pilaris. JAAD Case Rep. 2021, 12 :74–76. doi: 10.1016/j.jdcr.2021.04.025. [PMC free article] [PubMed] [CrossRef] [Google Scholar]

7. Kwak R.B., Hafeez F., Lian C., Nambudiri V.E. Paraneoplastic pityriasis rubra pilaris heralding onset of new hematologic malignancy. Am J Hematol. 2021, 96 :272–274. doi: 10.1002/ajh.25897. [PubMed] [CrossRef] [Google Scholar]

8. Bar-Ilan E., Gat A., Sprecher E., Zeeli T. Paraneoplastic pityriasis rubra pilaris: case report and literature review. Clin Exp Dermatol. 2017, 42 :54–57. doi: 10.1111/ced.13009. [PubMed] [CrossRef] [Google Scholar]

9. Remedios I.M., Jensen J.D., Beckum K., McKay K., Kissel R. Paraneoplastic pityriasis rubra pilaris as the presenting manifestation of metastatic squamous cell carcinoma. J Drugs Dermatol. 2014, 13 :610–612. [PubMed] [Google Scholar]

10. Vitiello M., Miteva M., Romanelli P., et al. Pityriasis rubra pilaris: was it the first manifestation of colon cancer in a patient with pre-existing psoriasis? J Am Acad Dermatol. 2013, 68 :e43–e44. doi: 10.1016/j.jaad.2010.05.013. [PubMed] [CrossRef] [Google Scholar]