Psoriasis diagnosis

Diagnosis of psoriasis is usually based on recognition of the characteristic plaque lesion, and not based on lab tests. 

The diagnosis is based on physical examination findings of the characteristic lesions of psoriasis. 

Psoriasis is a chronic skin and nail disease. About 10% of patients with psoriasis develop arthritis (PsA). Psoriasis may precede arthritis or vice versa. The diagnosis of PsA is based on landing psoriasis along with arthritis. 

Psoriasis is universal in occurrence. It is a disease of the skin characterized by variable clinical features. The cutaneous lesions are usually so distinct that a clinical diagnosis is easy to make. Psoriatic lesions are classified as erythrosquamous, which indicates that both the vasculature and the epidermis are involved.1... 

Figure 23-6 Seborrheic dermatitis in a classic distribution at hairline and between eyebrows and nasolabial folds. (From Habif TP. Psoriasis and other papulosquamous diseases. In Clinical dermatology, a color guide to diagnosis and therapy, ed. 4. Philadelphia Mosby, 2004 244.)...

About 2.1% of the U.S. population has psoriasis or more than 4.5 million adults in the U.S. Diagnosis usually is between ages 15 and 35. 

Psoriasis Multiple Sclerosis 1 9 after STD Shght increase in women men 3 1 undeveloped world Diagnosis usually 20-40yrs... 

A 55-year-old woman with psoriasis was treated with oral 5-methoxypsoralen and UVA photochemotherapy. After 40 treatments over 5 months she became unwell and complained of headaches, nausea, and abdominal pain. Laboratory tests confirmed a diagnosis of hepatitis. Six years earlier she had had flncloxacillin-indnced hepatitis. 

Abel EA (1992) Diagnosis of drug-induced psoriasis. Semin Dermatol, 11(4) 269-274. 

Methoxypsoralen and UVA (PUVA) caused photoallergic dermatitis in a psoriasis patient after 16 uneventful courses of PUVA treatment. The diagnosis of photoallergy was confirmed by reexposure to UVA and both oral and topical methoxypsoralen. UVB and UVC (< 290 nm) did not elicit the reaction and the photoallergy did not include trimethylpsoralen (Plewig et al. 1978). 

Skin A 56-year-old man with recalcitrant psoriasis treated with efalizumab developed multiple brown patches and papules, in the exact distribution of the previous psoriasis plaques the pathological diagnosis was seborrheic keratoses with overlapping features of solar lentigo [127 ]. 

Rule out nail involvement produced by dermatoses, such as psoriasis, atopic dermatitis, onychomycosis and lichen planus, which may present with an isolated symptom and lead to a false-positive diagnosis (Bennet 1975) in the absence of a thorough history and laboratory tests. 

Clinically, psoriasis of the hands presents as kerato-tic patches on the palms and often the bony prominences of the hands. The skin lesions on the palms do not display the classical features of psoriatic lesions elsewhere on the body. A high degree of suspicion is necessary to recognise the condition. The presence of psoriatic lesions elsewhere, e.g., on the elbows, knees, trunk and scalp, and the associated nail changes of psoriasis often help the physician to establish the diagnosis. 

Palmar psoriasis is often confused with chronic keratotic hand eczema. It is often difficult to differentiate it from a chronic eczema. Skin biopsies often show non-specific changes of an eczema rather than that of psoriasis, and the histological findings often do not help to confirm the diagnosis. 

Some skin conditions are more readily dis nos-able than others. Acne and psoriasis, for example, often do not necessitate further tests. The lesions, however, may he of an ambiguous nature or potentially malignant. In these cases, the physician takes a tissue sample (for example, a hiopsy or nail clippings) and submits it, usually with a differential diagnosis, to a laboratory. There, the sample undergoes a dermatopathological evaluation. 

Skin Eczema-like eruptions In a prospective cohort study in 92 patients treated with infliximab for a variety of disorders, with the exception of cutaneous psoriasis, 15 developed eczema [121 ]. In univariate analyses, a personal history of atopic symptoms was the only predictive factor (OR = 3.6) sex, age, principal diagnosis, dose and duration of infliximab, and concomitant use of other immunosuppressant had no effect. 

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