A Psoriasis. Clinical Presentation. 2 Types of Psoriasis. Plaque Psoriasis. 1 Introduction

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1 Clinical Presentation A Psoriasis Jennifer Soung, Mark Lebwohl Contents 1 Introduction 67 2 Types of Psoriasis 67 Plaque Psoriasis 67 Guttate Psoriasis 68 Pustular Psoriasis 69 Inverse Psoriasis 70 Erythrodermic Psoriasis 70 3 Specific Locations of Psoriasis 70 4 Keratoderma Blennorrhagicum (Reiter s Syndrome) 71 5 Conclusion 72 References 72 1 Introduction The clinical manifestations of psoriasis and its variants have been described for over two centuries. The diagnosis is typically made by the recognition of the classic and distinctive lesions well-demarcated erythematous plaques with adherent silvery scales. The most frequent areas of involvement include the elbows, knees, lower back, and buttocks but the disease can involve any cutaneous surface. Therefore, the evaluation of psoriasis should include a careful examination for the presence of lesions involving other areas including the perineum, scalp, nails, intertriginous areas, and genitalia. The disease varies widely in severity and extent of involvement as some patients present with a few isolated plaques and others can have complete coverage of their body surface. ariations in the morphology of psoriasis have been classified into several clinical subtypes, which will be described in the following section in further detail. Because psoriasis is usually a chronic, relapsing disease, it is important to appreciate that the clinical appearance is rarely stagnant and the lesions continually evolve [16]. 2 Types of Psoriasis Plaque Psoriasis More than 80% of patients who present with psoriasis have plaque psoriasis, also known as psoriasis vulgaris. The classic lesions are well circumscribed erythematous circular or ovoid plaques with adherent silvery scales (Fig. A1). Although psoriasis can affect any cutaneous surface, patients usually present as young adults with symmetric involvement of the extensor surfaces of the lower and upper extremities, gluteal cleft (Fig. A2), scalp and nailplates [13]. The lesions may begin as red, scaling papules that eventually evolve to form round-oval plaques, which can be easily differentiated from the surrounding normal skin. The plaques vary from a pink to red color and are usually covered by a thick silvery scale. The thickness of the scale can be quite variable depending on the site of involvement extremely dense in the scalp and more dispersed in the intertriginous areas. The diameter of the lesions can range

2 68 Chapter Clinical Presentation spares the palms, soles and face.although some patients are asymptomatic, approximately half of patients consider pruritus as the most distressing symptom [11]. Fig. A1. Note the sharply demarcated erythematous scaling oval plaques that typically affect the extensor surfaces Guttate Psoriasis Guttate psoriasis refers to the acute onset of generalized multiple small papules. This morphology most commonly affects children, adolescents, and young adults with no previous history of psoriasis but may also occur as an acute exacerbation of pre-existing plaque psoriasis. In many instances, an episode of guttate psoriasis is a sign of the patient s predisposition to develop generalized plaque psoriasis. Often, a history of streptococcal infection precedes this eruption by 1 or 2 weeks [15, 19]. The lesions in guttate psoriasis are easily distinguished as a distinct form of psoriasis. They are small, usually less than 1 cm in diameter, uniformly erythematous or pink papules with slightly less scale and induration than chronic lesions of plaque psoriasis (Fig. A3). Fig. A2. Classic plaque psoriasis of the intergluteal cleft from less than 1 cm to more than 10 cm. Small bleeding points may occur when the tightly adherent scales are removed from the surface of the plaque. This commonly noted clinical sign of psoriasis is called Auspitz sign and is neither sensitive nor specific for psoriasis [1]. Psoriasis is well known to develop at sites of physical trauma (scratching, sunburn or surgery), the isomorphic or Koebner s phenomenon [7]. The disease affects the extensor surfaces more than the flexor surfaces and usually Fig. A3. Guttate psoriasis. Multiple uniform small (less than 1 cm in diameter) lesions with less scale and induration compared to psoriasis vulgaris. Numerous papules appear abruptly on the trunk and extremities following recent streptococcal infection

3 A Psoriasis Jennifer Soung, Mark Lebwohl 69 These lesions tend to enlarge rapidly while remaining as single lesions and are generally found in crops on the trunk, buttocks, hips and extremities. The appearance of the guttate form with many small lesions may resemble other cutaneous conditions like pityriasis rosea or secondary syphilis. Pustular Psoriasis Unlike most psoriatic patients, those with this rare form of psoriasis (also called von Zumbusch psoriasis) can be systemically ill. The disease typically occurs in patients who have antecedent nonpustular psoriasis or a genetic predisposition and have recently withdrawn from systemic corticosteroids. Pustular psoriasis is the most severe form of psoriasis and can be life-threatening. In the generalized form, the trunk and extremities are covered with sterile pustules arising from the surface of large erythematous patches of skin (Fig. A4). The pustules on the affected skin eventually dry and peel. This condition results in a loss of the protective functions of the skin. In extremely ill patients, these pustules rapidly enlarge and become confluent, forming lakes of pus. Systemic symptoms include fever, diarrhea, arthralgias and chills. Less severe and localized variants of pustular psoriasis can occur on the palms and soles. This form is also known as palmar-plantar pustulosis. Patients with this type of psoriasis are typically females years of age. Palmar or plantar pustules develop which then turn dark brown and crust over creating a tender and diffusely eroded surface (Fig. A5). Although not life-threatening, this subtype can be particularly frustrating since affected patients have difficulty walking or using their hands. Patients with palmoplantar psoriasis experience greater functional and social disability than patients with psoriasis located elsewhere on the body [17]. A specific form of palmar plantar pustolosis is acrodermatitis continuea. These pustules are located on the fingertips or toes and are very painful and disabling. A final localized form of pustular psoriasis is often seen during an acute flare of psoriasis vulgaris as pustules on the surface of plaque type psoriasis. Fig. A4. Pustular psoriasis. Crops of sterile pustules arising on the surface of erythematous plaques cover the extremities Fig.A5. Pustular psoriasis. Sterile yellow pustules on the digits

4 70 Chapter Clinical Presentation Inverse Psoriasis This clinical subtype of psoriasis occurs in the flexural creases of the inguinal areas, submammary folds, gluteal fold, retroauricular fold, axillae, groin and genital regions. The presentation is the reverse of the classical presentation on extensor surfaces. Inverse psoriasis frequently occurs in patients who are obese. Lesions of inverse psoriasis are smooth with no visible scaling, unlike classical plaque psoriasis (Fig. A6). These deep red, well-demarcated plaques frequently contain moist white debris and extend to and stop at the junction of the skin folds. Infection, friction and heat may induce psoriasis in these flexural creases, a manifestation of the Koebner phenomenon. In the absence of visible scaling, this variant can be easily misdiagnosed as a fungal infection or erythrasma (a chronic superficial infection of the intertriginous areas of the skin) [8]. Erythrodermic Psoriasis Erythrodermic psoriasis is an acute, severe form of psoriasis characterized by generalized Fig. A7. Erythrodermic psoriasis. Note the inflamed red erythema of the plaque surface inflamed erythema and widespread scaling which affects more than 90% of the body surface area (Fig. A7). Like pustular psoriasis, the most common precipitating cause of erythrodermic form is withdrawal of systemic steroids and patients are usually systemically ill with fever, chills, rigors and arthralgias [2]. Patients usually suffer from extensive desquamation and generalized inflamed erythema resulting in a loss of the protective function of the skin. Multiple medical complications can develop including loss of the skin s ability to protect against infection, to maintain electrolyte balance, and to control body temperature. Therefore, loss of this barrier function making death from sepsis a well-known complication of erythrodermic psoriasis [6]. Fig. A6. Inverse psoriasis of the axilla. Note the absence of visible scales 3 Specific Locations of Psoriasis Although psoriasis favors certain areas, there are several other locations that should be examined in patients in whom the diagnosis of psoriasis is suspected. Nail involvement is characteristic of psoriasis and aids in diagnosis when characteristic skin changes are equivocal or absent. Psoriatic nail changes may occur alone but rarely in the absence of other cutaneous disease. Nail changes can affect some or all of the fingernails or toenails and may extend to the entire nail including the proximal and lateral nail folds and the hyponychium.

5 A Psoriasis Jennifer Soung, Mark Lebwohl 71 The most common stigma of nail psoriasis is pitting few to multiple tiny punched-out depressions on the nail plate surface. These pits result from psoriatic involvement of the nail matrix producing abnormal nail plate growth. Psoriasis of the nail bed can also cause separation of the nail from the nail matrix, referred to as onycholysis. These changes can then result in a nail losing its structural integrity and thick crumbling nails which can resemble a fungal infection (Fig. A8). In addition, a specific localized color change in the nail may occur that resembles the tan-brown color of new motor oil, the oil drop sign (Fig. A9). Nail involvement with psoriasis can be the most troublesome aspect for patients who relate significant quality of life issues [12]. Fig. A10. Psoriasis of the nails. The oil drop sign Psoriasis of the scalp is a common site of plaques similar to those of the skin except that the scale is more adherent (Fig. A10). Some individuals develop psoriasis on the palms and soles as the only sites involved or before other regions are affected. The patterns of presentation on the palms and soles can vary from superficial red plaques with thick brown scale to smooth, deep red plaques such as those found in the flexural areas. Uncommonly, psoriasis can also affect the oral mucosa [4]. 4 Keratoderma Blennorrhagicum (Reiter s Syndrome) Fig.A8. Scalp psoriasis. Sharply defined plaques characterized by erythema and silvery scale Patients with Reiter s syndrome, a reactive immune response characterized by urethritis and/or cervicitis, peripheral arthritis of more than 1 month s duration, can develop psoriasiform skin lesions 1 2 months after the onset of arthritis. The distinctive lesions, known as keratoderma blennorrhagica, appear on the soles, toes, legs, scalp and hands. The psoriasiform plaque has distinctive circular scaly borders that develop from fusion of papulovesicular plaques with thickened yellow scale. Similar variants of psoriasis can be found on the penis (balanitis circinata). Fig. A9. Onycholysis of the nails. Psoriatic involvement of the nail matrix results in poorly formed nails

6 72 Chapter Clinical Presentation 5 Conclusion t Recognition of the variation in the clinical presentations of psoriasis is important for many reasons. First, some forms of psoriasis such as pustular or erythrodermic psoriasis can be life-threatening and must be managed aggressively. Second, different forms of psoriasis respond differently to different treatments. For example, mild topical corticosteroids or topical immunomodulators are highly effective in inverse psoriasis but much less effective on thick plaques of the elbows or knees. Similarly, guttate psoriasis often responds well to phototherapy with ultraviolet B, at times giving long remissions that are not as easily achieved with a typical patient who has generalized plaque psoriasis. Finally, as the genetic basis of psoriasis is better understood, it will be interesting to see if different forms of the disease correspond to variations in genetic susceptibility or to differences in gene expression. As we get closer to the identification of genetic defects in psoriasis, variations in the clinical manifestations of the disease may be easier to understand and lead to better therapeutic outcomes. References 1. Bernhard JD (1990) Auspitz sign is not sensitive or specific for psoriasis. J Am Acad Dermatol 22 : Boyd AS, Menter A (1989) Erythrodermic psoriasis. J Am Acad Dermatol 21 : Brockbank JE, Schentag C, Rosen C, Gladman DD (2001) Psoriatic arthritis (PsA) is common among patients with psoriasis and family medicine clinical attendees. Arthritis Rheum 44 : S94 4. Bruce AJ (2003) Oral psoriasis. Dermatol Clin 21 : Christophers E, Kiene P (1995) Guttate and plaque psoriasis. Dermatol Clin 13 : Green MS, Prystowsky JH, Cohen SR, Cohen JI, Lebwohl MG (1996) Infectious complications of erythrodermic psoriasis. J Am Acad Dermatol 34 : Habif TP (1996) Clinical dermatology: Diagnosis and therapy. Mosby-Year Book, St. Louis, pp Holdiness MR (2002) Erythrasma and common bacterial skin infections. Am Fam Physician 67 : Jones SM, Armas JB, Cohen MG, Lovell CR, Evison G, McHugh NJ (1994) Psoriatic arthritis: outcome of disease subsets and relationship of joint disease to nail and skin disease. Br J Rheumatol 33 : Kane D, Greaney T, Bresnihan B, Gibney R, FitzGerald O (1999) Ultrasonography in the diagnosis and management of psoriatic dactylitis. J Rheumatol 26: Koo J (1996) Population-based epidemiologic study of psoriasis with emphasis on quality of life assessment. Dermatol Clin 14 : Larko O (1995) Problem sites: scalp, palm and sole, and nails. Dermatol Clin 13 : Lebwohl MG (2003) Psoriasis. Lancet 361 : Moll JM, Wright (1973) Psoriatic arthritis. Semin Arthritis Rheum 3 : Naldi L (2001) Family history of psoriasis, stressful life events, and recent infectious disease are risk factors for a first episode of acute guttate psoriasis: results of a case-control study. J Am Acad Dermatol 44 : Nevitt GJ, Hutchinson PE (1996) Psoriasis in the community: prevalence, severity and patients beliefs and attitudes towards the disease. Br J Dermatol 135 : Pettey AA, Balkrishnan R, Rapp SR, Fleischer AB, Feldman SR (2003) Patients with palmoplantar psoriasis have more physical disability and discomfort than patients with other forms of psoriasis: implications for clinical practice. J Am Acad Dermatol 49 : Ruderman EM (2003) Evaluation and management of psoriatic arthritis: The role of biologic therapy. J Am Acad Dermatol 49 : Telfer NR, Chalmers RJ, Whale K, Coleman G (1992) The role of streptococcal infection in the initiation of guttate psoriasis. Arch Dermatol 128 : Winchester R (1995) Psoriatic arthritis. Dermatol Clin 13 :