In most cases, diagnosis of psoriasis is fairly straightforward.
- Physical exam and medical history. Your doctor usually can diagnose psoriasis by taking your medical history and examining your skin, scalp and nails.
- Skin biopsy. Rarely, your doctor may take a small sample of skin (biopsy) that's examined under a microscope to determine the exact type of psoriasis and to rule out other disorders. A skin biopsy can generally be done in a doctor's office after application of a local anesthetic.
Conditions that can look like psoriasis
Other conditions that may look like psoriasis or may occur at the same time as psoriasis include:
Apr. 11, 2014
- Seborrheic dermatitis. This type of dermatitis is characterized by greasy, scaly, itchy, red skin. It's often found on oily areas of the body, such as the face, upper chest and back. Seborrheic dermatitis can also appear on the scalp as stubborn, itchy dandruff.
- Lichen planus. This is an inflammatory, itchy skin condition that appears as rows of itchy, flat-topped bumps (lesions) on the arms and legs.
- Ringworm of the body (tinea corporis). Ringworm is caused by a fungal infection on the top layer of your skin. The infection often causes a red, scaly ring or circle of rash.
- Pityriasis rosea. This common skin condition usually begins as one large spot (herald patch) on your chest, abdomen or back, which then spreads. The rash of pityriasis rosea often extends from the middle of the body, and its shape resembles drooping pine tree branches.
- Bolognia JL, et al. Dermatology. 3rd ed. Philadelphia, Penn.: Saunders Elsevier: 2012. https://www.clinicalkey.com. Accessed Dec. 6, 2013.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Dec. 6, 2013.
- Papadakis MA, et al. Current Medical Diagnosis & Treatment 2013. 52nd ed. New York, N.Y.: The McGraw-Hill Companies; 2013. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=1. Accessed Dec. 6, 2013.
- Psoriasis. National Institute of Arthritis and Musculoskeletal and Skin Diseases. http://www.niams.nih.gov/Health_Info/Psoriasis/.Accessed Dec. 8, 2013.
- Weigle N, et al. Psoriasis. American Family Physician. 2013;87:626.
- Feldman SR, et al. Epidemiology, clinical manifestations, and diagnosis of psoriasis. http://www.uptodate.com/home. Accessed Dec. 6, 2013.
- Armstrong AW, et al. The association between psoriasis and obesity: A systematic review and meta-analysis of observational studies. Nutrition and Diabetes. 2012;2:1.
- Korman N. Comorbid disease in psoriasis. http://www.uptodate.com/home. Accessed Nov. 16, 2013.
- Azfar RS, et al. Increased risk of diabetes mellitus and likelihood of receiving diabetes mellitus treatment in patients with psoriasis. Archives of Dermatology. 2012;148:995.
- Armstrong AW, et al. Coronary artery disease in patients with psoriasis referred for coronary angiography. American Journal of Cardiology. 2012;109:976.
- Ahlehoff, et al. Psoriasis and risk of atrial fibrillation and ischaemic stroke: a Danish nationwide cohort study. European Heart Journal. 2012;33:2054.
- Yeung H, et al. Psoriasis severity and the prevalence of major medical comorbidity: A population-based study. JAMA Dermatology. 2013;149:1173.
- Wan J, et al. Risk of moderate to advanced kidney disease in patients with psoriasis: population based cohort study. BMJ. 2013;347:1.
- Papoutsaki M, et al. Treatment of psoriasis and psoriatic arthritis. Biodrugs. 2013;27:3.
- Feldman SR, et al. Treatment of psoriasis. http://www.uptodate.com/home. Accessed Dec. 6, 2013.
- Almutawa F, et al. Systematic review of UV-based therapy for psoriasis. American Journal of Clinical Dermatology. 2013;14:87.
- De Migeul R, et al. Efficacy, safety, and cost of Goeckerman therapy compared with biologics in the treatment of moderate to severe psoriasis. International Journal of Dermatology. 2009;48:653.
- Garcia-Perez ME, et al. New therapies under development for psoriasis treatment. Current Opinion in Pediatrics. 2013;25:480.
- Korteum KR, et al. Results of Goeckerman treatment for psoriasis in children: A 21-year retrospective review. Pediatric Dermatology. 2010;27:518.
- Aloe. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Dec. 9, 2013.
- Fish oil. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Dec. 9, 2013.
- Oregon grape. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Dec. 9, 2013.
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