P

Palmoplantar Pustulosis

Groups of sterile pustules occur in crops on one or both hands and/or feet. They are associated with thickened, scaly, red skin, which easily develops painful cracks (fissures). The condition varies in severity and may persist for many years. It is not known what causes exacerbations or remissions. Palmoplantar pustulosis is not infectious to other people and does not influence one's general health. However the discomfort can be considerable, interfering with working and leisure activities. Walking for prolonged periods may cause exacerbations on the feet. If the palms are involved, manual activities may be uncomfortable, and injuries may aggravate the disorder. Certain occupations are therefore inadvisable for affected individuals. It is much more common in those who smoke (or have smoked in the past), sometimes runs in families and rarely occurs before adulthood. Some affected persons also have psoriasis, when it is known as pustular psoriasis of the palms and soles. Dermatitis and tinea pedis (a fungus infection) may appear similar, but require different treatment.

Papular Urticaria

Papular urticaria is a skin condition, which most commonly affects children. Crops of very itchy red bumps, 0.2 - 2 cm in diameter, appear every few days. Sometimes each spot develops a fluid-filled blister up to one centimeter in diameter. They are most often on the legs and other uncovered areas such as forearms and face but sometimes they are scattered in small groups all over the body. It is difficult not to scratch the spots, which become crusted and may get infected - they are then pussy and sore. Sometimes one new spot provokes all the old ones to come up again and itch intensely. The spots seem to remain for a few days to a few weeks and can leave persistent marks or scars, especially if they have been scratched deeply.

Pemphigus

Pemphigus (pemphigus vulgaris) is an auto-immune disease in which the body produces antibodies to the skin cells in the epidermis resulting in flacid blisters of the skin and mucous membranes. This may result in serious complications and requires the use of oral immunosupressive drugs, including prednisone.

Pemphigoid

Pemphigoid ( balluous pemphigoid vulgaris) is an auto-immune disease in which the body produces antibodies to the basement membrane (the underlying layer of the skin) resulting in tense blisters. This is less serious than pemphigus and tends to occur in older patients.

Perioral Dermatitis

Perioral dermatitis is a common facial skin problem. It rarely occurs in men. Groups of itchy or tender small red spots appear most often around the mouth. They spare the skin bordering the lips (which then appears pale) but develop on the chin, upper lip and cheeks. The skin surface becomes dry and flaky. Often the skin around the nose is affected too, and sometimes that around the eyes. Patients who are susceptible to perioral dermatitis tend to have an oily face, at least in the affected areas.

Photosensitivity

Some people develop a rash because their skin is sensitive to sunlight; this is known as Photosensitivity. Patients may not associate their skin complaint with the light. It is not always the bright summer sun, which is responsible; some people also react to winter daylight, and very sensitive subjects may even be affected by fluorescent lamps indoors. Photosensitivity occurs for a variety of reasons. Some known causes include:

• Medicines taken internally.
• Chemicals, fragrances or plant materials in contact with the skin.
• A metabolic disorder such as Porphyria.
• Autoimmune disease (self-allergy), such as Lupus Erythematosus.

Phototherapy

Phototherapy is a treatment using certain types of electromagnetic radiation for skin disorders.

Pitted Keratolysis

Pitted keratolysis is a descriptive title for a skin condition affecting the soles of the feet. It affects those who sweat profusely (hyperhidrosis) especially if they wear occlusive shoes or boots for long periods. Corynebacteria, and/or possibly the bacteria Dermatophilus congolensis is the cause of it. The. The result is very smelly feet, due to infection of the soles. Either the forefoot or the heel or both become white with clusters of punched-out pits. The appearance is more dramatic when the feet are wet. Very rarely, the fingers are similarly affected. There is a variant of pitted keratolysis where there are more diffuse red areas on the soles.

Pityriasis Alba

Pityriasis alba is a common skin condition affecting children and occasionally young adults. Several round or oval slightly scaly pink patches appear, leaving pale marks when the redness has faded. Pityriasis alba patches are more apparent in summer, especially in dark-skinned children, because they don't tan as well as the surrounding skin. Pityriasis alba is a mild form of dermatitis of unknown cause. It will clear up after a few months, or in some cases persist two or three years. The color gradually returns completely to normal.

Pityriasis Rosea

Pityriasis rosea is a common harmless viral infection of the skin which is characterized by pink to red oval rose petal shaped lesions on the torso, arms, and legs sparing the hands, feet and face. typically there is an intial "herald patch" which precedes the generalized rash. There maybe some itchiness associated with it and it can be treated with steroid creams and light therapy. It typically occurs only once in a lifetime.

Pityrosporum Folliculitis

Pityrosporum folliculitis is a condition where the yeast, pityrosporum (also called Malassezia furfur), gets down into the hair follicles and multiplies, setting up an itchy, acne-like eruption. This yeast is a normal skin inhabitant, different from the yeast, which causes thrush, and from baker's or food yeast. Everyone has it on his or her skin but in most cases it causes no problem. The condition affects young to middle-aged adults of either sex. It is associated with a tendency to seborrhoeic eczema or severe dandruff. The rash consists of tiny itchy dome-shaped pink papules with an intermingling of small pustules. The spots are located mainly on the upper back, shoulders and chest. Sometimes spots are found on the forearms, back of the hands, lower legs and face. The tendency to scratch spots is greatest on the forearms, face and scalp. Most patients have oily skins.

Plant Dermatitis

Plant dermatitis is caused by reaction to skin contact with certain plants. It is not always obvious which plant is responsible for a flare-up of dermatitis. Sometimes a rash may develop without direct contact with the plant; the juices on clothing etc may be enough, or transmitted from the fingers. The rash may take various forms. Some plants only cause a rash if the sun is shining on the skin at the same time (phytophotodermatitis). Big blisters appear on exposed parts, which have been in contact with the plant. Anyone can get this kind of plant dermatitis, which settles leaving brown marks, which may last several months. Plant dermatitis is not contagious and the blister fluid does not spread the rash. The rash appears between four hours and 10 days after exposure to the plant, depending on individual sensitivity and the amount of contact. Sometimes more rash appears after treatment has begun due to blood stream spread of the allergy to other areas.

Pompholyx

Pompholyx is also known as, vesicular hand and/or foot eczema. It is a common type of eczema affecting the hands (cheiropompholyx), and sometimes the feet (pedopompholyx). The condition may be mild with only a little peeling, or very severe with big blisters and cracks, which prevent work. The first (acute) stage shows tiny blisters (vesicles) deep in the skin, associated with itching and a burning feeling. The later and more chronic stage shows more peeling, cracking, or crusting. Some patients will have mostly one stage, and some patients will have mostly the other. Some times both stages occur at the same time. Secondary infection with Staphylococcal bacteria is not infrequent. The result is pain, redness, swelling and crusting or pustules. Pompholyx of the hands is aggravated by contact with irritants such as water, detergents and solvents. Contact with them must be avoided as much as possible and protective gloves worn.

Porphyria Cutanea Tarda

Porphyria cutanea tarda is the most common type of porphyria. Prophyria cutanea tarda (PCT) is due to a defective enzyme in the liver (uroporphyrinogen decarboxylase) involved in synthesis of the red pigment in blood cells (haem). The results is an increase in porphyrins in the skin, resulting in photosensitivity i.e. the skin is damaged by light. Affected individuals develop fragile skin, sores (erosions), blisters (vesicles and bullae), and tiny cysts (milia) on the sun-exposed areas i.e. the back of the hands and the forearms. They may notice that they sunburn easily. Some people develop mottled brown patches around the eyes and increased facial hair. Occasionally the skin becomes hardened (sclerodermoid) on the neck, face or chest. There may be small areas of permanent baldness (alopecia) or ulcers. There is a genetic predisposition to PCT. It generally begins in mid-adult life after exposure to certain chemicals, which increase the production of porphyrins (precursors of haem) in the liver.

Pseudofolliculitis Barbae

Pseudofolliculitis barbae is also known as shaving rash or razor bumps. It is a foreign-body inflammatory reaction surrounding ingrown facial hair, which results from shaving. The problem occurs more commonly in people who have curly hair.

Psoriasis

Psoriasis is a disorder of the skin, which typically consists of red patches covered by silvery-white scales. These red scaly patches are usually found on the elbows, knees, lower back, and scalp although not infrequently patches appear elsewhere including the nails. When psoriasis involves the groin, armpits, and genital area and beneath the breasts it tends to be less scaly and have a glazed appearance. Psoriasis infrequently affects the face. It does not cause scarring and rarely results in hair loss. Psoriasis is very common. Approximately 2% of adults have psoriasis. Its exact cause is unknown but the result is skin, which grows about seven times more quickly and thickly than usual. It is thought to be due, at least in part, to an abnormal immune reaction against some component of the skin. Genetic factors play a part; only some families develop the condition, and about half those affected know of someone else in the family with it. The rash often seems to start after some sort of trigger factor. This may be emotional stress, skin injury (cuts and scratches for example), a streptococcal sore throat, hormones (it often first occurs at puberty), or rarely, certain medications. These factors should be avoided whenever possible by people with psoriasis. Psoriasis is not an allergy, nor is it infectious to others.