Graphic # 5: Psoriasis

Subjective Data

The graphic presents a patient with thick red lesions whose surface appears silvery.

Objective Data

The graphic presents scaly patches that appear delineated, raised and dry when compared to unaffected areas. They take an irregular to oval shape, differ in size and coalesce to form larger patches that appear flaky and crusty in appearance. The patches are rough, firm and erythematous. There is no evidence of bleeding in the affected areas.


Differential diagnosis:

  • Lichen Planus

The characteristics of lichen planus disqualify the disease as the probable diagnosis. Lichen planus presents as flat topped (planar), purple, pruritic, papules, plaques and polygonal lesions (Health & Matin, 2017). They often have white lines that appear reticular and lacy that are called (Wickham striae). And they appear in shiny clusters or lines in regions where skins has been scratched.

  • Nummular eczema,

This presents as an itchy rash that occurs as round, (often described as nickel, dime or coin size) shaped patches on the skin. With time, these lesions clear in the center and appear scaly (Poudel & Belbase, 2015). These coin shaped patches are pruritic and occur often on legs and arms as a result of dry skin.

  • Psoriasis Seborrheic dermatitis

This skin inflammation presents as red regions with white or yellow scales that appear greasy. It ranges from mildly flaky and can become red, inflamed and sensitive. In some body parts it appears as round well defined red patches that are scaly.

  • Mycosis

This is a fungoide that presents as erythematous patches that are slightly infiltrated and desquamating in a fine manner (Patel, et al. 2018). In later stages of this diseases, these patches thicken and become red. Diagnosis of this disease is dependent upon a biopsy.

Prospective diagnosis: Psoriasis.

This diagnosis is based on the peculiar morphologic elements that are characteristic of psoriatic plaques including erythema, desquamation, infiltration, distinct boundary, irregular to oval shape of the patches, coalescence, the distribution of the patches, and their flaky, scaly characteristic that appears silvery (Kim, et al. 2017; Sarac, et al. 2016; Watkins, 2016; Wiegle, & McBane, 2014).

Psoriasis is a significantly common immune-mediated inflammatory disease that affects the skin and joints predominantly (Watkins, 2016). The disease affects the skin and in some instances the nails and has been associated with several other comorbidities (Sarac, et al. 2016). Psoriasis presents as skin lesions that are localized or generalized which appear in most instances as red papules and plaques that are sharply demarcated and symmetrical (Sarac, et al. 2016). These are usually covered with silver scales. The most frequent form of psoriasis that is witnessed is the psoriasis vulgaris also called plaque psoriasis which manifests as erythematous plaques that have sharp boundaries that are covered with squamae that is pearlescent (silvery) (Sarac, et al. 2016). The lesions in psoriasis vulgaris are often symmetrically distributed and in most instances are localized in specific regions including the scalp, sacral region, elbows and knees. In most instances, these lesions may result from a traumatic incident

To exclude other dermatological disorders, a skin biopsy or scraping may be conducted. Scraping the surface of the psoriatic plaque with a blunt scalpel results in the falling off of squamae in the form of layers of white lamellae (Watkins, 2016). These squamae are coherent when removed, much in the same way that candle wax acts (Watkins, 2016). The desquamation characteristic to psoriasis is referred to as the “wax spot phenomenon” and is indicative of parakeratotic hyperkeratosis (Sarac, et al. 2016). When it is further scraped, the psoriatic plaque exhibits a wet layer that is adhesive to the lesion. This is a pathognomonic sign that is indicative of psoriasis and is known as the “last membrane phenomenon” (Sarac, et al. 2016). If the lesion is scraped further, an erythematous background is revealed with bleeding foci that appears as red pinpoints that are known as the “auspitz sign” (Sarac, et al. 2016).


Treatment of psoriasis is dependent on the severity of the disease. Psoriasis manifests as mild, moderate and severe (Wiegle & McBane, 2014). A large percentage of patients with psoriasis have mild and moderate psoriasis that affects the body surface to an extent that is five percent or less without any occurrence on the genitals, feet, face and hands. Topical therapies such as corticosteroids, tazarotene (tazorac), calcinueurin inhibitors and vitamin D analogs (Wiegle & McBane, 2014). Other uncommon therapies that can be used include topical therapies such as salicylic acid, non-medicated moisturizers, anthralin and coal tar (Kim, et al. 2017).

Often corticosteroids are used in the treatment of psoriasis and have been associated with increased improvements in the reduction of symptoms of psoriasis. These however have been associated with irritation, wound healing impairments and skin atrophy (Wiegle & McBane, 2014). Extended use of corticosteroids has also been associated with increased risk of these systemic effects. It is important to inform the patient that tapering the use of corticosteroids will result in recurrence of symptoms after weeks or months.

If the choice is vitamin D analogs, then calcitrol (vectical) and calcipotriene (donovex) are recommended as monotherapy or they can be used when combined with phototherapy as a treatment of psoriasis for individuals who have psoriasis that has extended five to twenty percent of the surface of the body (Kim et al. 2017). This is because while these medications may have slower action onsets, they have extended disease free intervals than the corticosteroids.

The teratogenic topical retinoid tazarotene can be used alongside corticosteroids or with moisturizers (Wiegle & McBane, 2014). Their effectiveness in extending the disease free interval is greater than that of the corticosteroids. Calcineurin inhibitors including pimecrolimus (Elidel) and tacrolimus (Protopic) are used especially in patients who are two years and older (Wiegle & McBane, 2014). They are associated with improved psoriasis symptoms with reduced skin atrophy when compared with corticosteroids and are recommended as first line treatments to be used in flexural and facial psoriasis.

Patients who have severe psoriasis that is symptoms covering more than 5 percent of the body and involves the feet, face, hands, and genitals are recommended treatment with phototherapy alongside systemic therapies (Wiegle & McBane, 2014). These systemic therapies include cyclosporine (sandimmune), methotrexate, acitretin (soritane), and other biological therapies (Wiegle & McBane, 2014).

Methotrexate is to be applied on a weekly basis alongside folate therapy to reduce adverse effects. Cyclosporine has been associated with rapid symptom alleviation but increased drug interactions and adverse effects when used in the long-term (Kim, et al. 2017). Therefore, it is used as a bridge therapy when other slower onset therapies are being introduced. Acitretin has a slow onset approximately taking three to six months and has been associated with hyperlipidemia, mucocutaneous lesions (Wiegle & McBane, 2014). Its effectiveness is witnessed when it is coupled with phototherapy. Biological therapies are most commonly used in the treatment of moderate and severe psoriasis. Infliximab, a biological therapy, has been associated with increased response to treatment (Wiegle & McBane, 2014).

All in all, the main purpose of treating psoriasis is to improve the skin, joint and nail lesions and to improve the patient’s quality of life. Treatment of psoriasis, depending on the severity, should also depend on the patients comorbidities. It should be individualized to include the preferences of the patient and in some instances of severity may involve consultation with a dermatologist.




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