PSORIASIS DESCRIPTION

There are several different types of psoriasis.

Psoriasis Vulgaris
This is the most common form of psoriasis. It is characterised by a symmetrical skin rash. The plaques may vary in size and shape and smaller lesions may merge into larger ones. Hair thinning may also be a feature.

Sites commonly affected include:

•	Scalp (does not tend to scar when healing);
•	Elbows;
•	Knees;
•	Lower back (lumbosacral);
•	Body flexures (skin folds) such as the armpits and under the breasts;
•	Genital areas.

Guttate psoriasis
Guttate psoriasis occurs two to three weeks following a streptococcal throat. It is usually seen in children and young adults with a genetic predisposition to psoriasis. It is characterised by numerous small (less than 1cm) psoriatic plaques that appear suddenly on the trunk and limbs. Guttate psoriasis usually disappears within three months but can recur.

Napkin psoriasis
In Napkin psoriasis the skin lesions are generally confined to the nappy area but may occur elsewhere. This type of psoriasis is self-limiting. Other types of psoriasis may develop later in life.

Unstable psoriasis
Unstable psoriasis may occur spontaneously or follow infection or stress. The Psoriatic plaques are bright red in colour and may lack the scaly surface associated with other forms of psoriasis. The plaques may itch or become tender.

Unstable psoriasis may progress to Erythrodermic or generalised Pustular psoriasis. Urgent assessment and inpatient treatment is necessary.

Erythrodermic psoriasis
Erythrodermic psoriasis usually develops in individuals with known psoriasis. More than 90 percent of the body surface is involved. Complications include:

• Difficulty controlling body temperature;
• Dehydration;
• Heart failure.

Left untreated, this type of psoriasis is life threatening.

Generalised Pustular psoriasis
Generalised Pustular psoriasis may be precipitated by the discontinuation of steroid therapy to treat Psoriasis Vulgaris. However, it may also occur in individuals with no previous evidence of psoriasis. It is a potentially lethal condition with the same complications as Erythrodermic Psoriasis. It is characterised by:

• Psoriatic plaques;
• Numerous small, sterile, yellow pustiles develop on a red background;
• Red, sore skin.

Erythrodermic psoriasis and Generalised Pustular psoriasis are dermatological emergencies and should be managed in hospital.

Palmplanter Pustulosis
This form of psoriasis is often associated with cigarette smoking. It is characterised by:
• Localisation of lesions to the palms of the hands and soles of the feet;
• Yellow pustules that later turn brown;
• Other parts of the body affected by psoriasis.

Nail psoriasis
50 percent of individuals with skin disease have nail psoriasis. However, nail psoriasis can appear in the absence of any skin disease. It is characterised by:
• Small pinhead sized pits on the nail;
• Discolouration of the nail bed;
• Thickening of the nails.

Psoriatic arthritis
Seven percent of patients with psoriatic skin disease also have psoriatic arthritis. However, psoriatic arthritis may occur in the absence of skin disease, particularly where there is a family history of psoriasis. Psoriatic arthritis can be severe and disabling in about 5 percent of patients.

PSORIASIS RELATED ITEMS

PSORIASIS DEFINITION	PSORIASIS TREATMENTS
PSORIASIS DESCRIPTION	PSORIASIS PROGNOSIS
PSORIASIS CAUSES	PSORIASIS INFORMATION
PSORIASIS SYMPTOMS	PSORIASIS PREVENTION
PSORIASIS DIAGNOSIS