Psoriasis
Psoriasis is the best known of the group of erythematosquamous diseases. Although there are many different hypotheses about its aetiology, no definite cause has been found. A role for genetic factors is reported in 60–70% of patients, but the remaining group is entirely sporadic. How it is transmitted is not clear. Recently, some views hold that there are two separate groups – one with early onset (15–20) and one with late onset (50–55) – that have the same clinical findings but differ genetically. No single gene has been identified, and inheritance is accepted to be multifactorial. Among environmental factors, emotional influences receive the most attention. Stress, anxiety, depression and sudden grief can be triggers. The effect of such psychological factors is thought to be around 60–70%. They can play a role both at the onset of the disease and in its flare-ups. Psoriasis is not an itchy disease, but severe itching can occur at times, and this parallels the severity of the psychological disturbance rather than the severity of the disease. It is emphasised that patients are often people who lack self-confidence, are introverted and have weak social relationships, and most often that there are disturbances in the mother–child relationship. Another important secondary factor is trauma. The appearance of the disease’s lesions after mechanical, physical or chemical trauma is called the Koebner phenomenon and can also be seen in other diseases such as lichen planus and vitiligo. Scratching in particular can trigger the onset of small lesions. In some cases bacteria are also thought to have an aggravating effect. Streptococcal upper respiratory tract infections receive the most attention. A flare-up may be seen one to two weeks after the infection. Their effect is greater in the type with small lesions, called the guttate type, seen especially in children, and regression may be seen when the foci of infection are eliminated. Foci of infection may sometimes also play a role in the very rare generalised pustular types. An autoimmune mechanism has been widely investigated, but no clear clues or link have been found; however, it has not been completely ruled out either. Although they are not a direct cause, some medicines have been found to have serious triggering effects. Lithium comes first among these; beta-adrenergic blockers, ACE inhibitors, NSAIDs and salicylates can also be triggers.
Its frequency in the population is 1–3%. The disease is most common in white people and affects men and women equally. It is very rare in childhood and is most common between the ages of 10 and 35. Its location is determined mostly by triggering traumas; the knees, elbows and scalp are the most common sites. The most common type is called psoriasis vulgaris and is located on exposed areas of skin and extensor surfaces. These lesions take the form of dry, white scales on classic erythematous papules. Lesions that are small and drop-like at first may enlarge and thicken as they become older. Types located on the scalp are similar, but they are hard to recognise among the hair; in the short term they do not harm the hair, but if they persist for a very long time they can lead to weakening and thinning. On the palms and soles keratosis predominates and erythema becomes harder to see. In the skin folds, scales cannot adhere because of friction and moisture, and erythematous plaques without scale are seen. When the nails are involved, thickening and discolouration of the nails are seen. Small pits (pitting), orange-coloured spots (oil spots) and subungual keratosis are very typical.
The differential diagnosis has features depending on the region. Psoriasis vulgaris on exposed areas is most often confused with lichen simplex chronicus, pityriasis rosea, superficial fungal diseases, signs of secondary syphilis and pityriasis rubra pilaris. In the skin folds it is confused with superficial fungal diseases, erythrasma and intertrigo; scalp involvement especially with seborrhoeic dermatitis and types of chronic eczema; and palmoplantar involvement again with fungal diseases, lichen simplex chronicus and signs of secondary syphilis. Nail involvement may be confused primarily with fungal diseases and traumatic disorders.
The success of treatment depends on harmony between patient and doctor, and the important and active role lies with the doctor. Because of the strange scaly signs on their skin, patients feel dirty, guilty and excluded from society. Their relationships with people are weak and their self-confidence is very low. The doctor’s approach to the patient is very important; the doctor should approach the patient with a smile in a way that wins their trust and puts them at ease. During the examination, a gentle, caring and measured touch with the bare hand is very important for the patient; it shows that the patient is not found repulsive, is not excluded and is trusted. This approach increases the patient’s confidence in themselves and in the doctor and makes adherence to treatment easier. Patients should not be given expectations of miracles, but the doors of hope for improvement should certainly not be closed either. Psychiatric support is beneficial in almost all patients.
Psoriasis Vulgaris
Psoriasis vulgaris is the most common clinical form of the disease. Lesions are usually located on the knees, elbows, sacral region and, on the scalp, behind the ears. The morphology of psoriasis skin lesions is very variable.
Candle-wax sign: Lesion scraped with a blunt object sheds its scales in white lamellae. This shedding is likened to the whitening and layer-by-layer peeling seen when scraping wax that has dripped onto a flat surface and dried, and so it is called the candle-wax sign.
Koebner phenomenon: A patient with active psoriasis develops typical psoriasis lesions in the area of an experimentally applied trauma 8–10 days later; this is called the Koebner phenomenon. The exact opposite is the so-called reverse Koebner phenomenon, in which a sudden rapid improvement is seen in all lesions after trauma.
Inverse Psoriasis
A type of psoriasis affecting the groin, vulva, armpits, gluteal cleft and other body folds. Scaling is greatly reduced or absent. The most commonly affected areas are the nappy area in babies and the armpits.
Guttate Psoriasis: A type that may appear especially after tonsil or throat infections. Widespread small drop-shaped plaques form on the body. Guttate psoriasis sometimes regresses after antibiotic treatment.
Pustular Psoriasis: In this type of psoriasis, yellow, pus-filled, pimple-like bumps are seen. Most often it occurs only on the palms and soles and remains confined to these areas. Much more rarely it can cause widespread redness and tiny yellow-tipped, pimple-like lesions on the body. This widespread type, called generalised pustular psoriasis, is a serious condition and therefore requires treatment in hospital.
Erythrodermic Psoriasis: A rare form. There is redness and peeling over the whole body surface. It is another severe type of the disease and needs to be treated in hospital with systemic medicines (given by mouth, as injections under the skin or as infusions).
Nail involvement
Nail involvement ranges from 10% to 50%. It is common in patients with psoriatic arthropathy. Nail bed findings include onycholysis, splinter haemorrhages, oil-drop discolouration, nail bed hyperkeratosis, pitting, leukonychia, red spots in the lunula, thickening of the nail plate and crumbling of the nail plate. NAPSI is the Nail Psoriasis Severity Index. The nail is divided into 4 quadrants and scored from 0 to 4 according to the presence or absence of matrix and nail bed findings. After the matrix and nail bed NAPSI values of the hands and feet have been assessed separately, the total is evaluated as the NAPSI (0–40 for each hand or foot).
Andrews’ Pustular Bacterid
In this disease, pus-filled, pimple-like lesions are seen on the palms and soles. Sometimes these lesions may also be filled with a clear fluid. They may sometimes merge to take on a honeycomb appearance. Usually no organism grows inside these pimple-like lesions; in other words, they are sterile.
The disease can develop after an infection of the teeth, tonsils or sinuses. It usually improves as this infection resolves.
The disease lasts for years with periods of flare-up and improvement. Antibiotics called tetracyclines and topical corticosteroid creams can be used in its treatment. In patients resistant to treatment, PUVA therapy or acitretin treatment can be used.
Infantile Acropustulosis
A disorder characterised by recurrent, intensely pruritic papulovesicular or vesiculopustular lesions appearing on the palms and soles, particularly in babies aged 2 to 10 months. It is seen predominantly in Black infants. Less often, the wrists, forearms, face and trunk, as well as the tops of the feet and hands, may also be affected. The lesions tend to appear at 2–4 week intervals and last 1 to 2 weeks. The disorder disappears spontaneously by the time the patient is 2 to 3 years old.
GPP of Pregnancy (Impetigo herpetiformis)
It appears in the last three months of pregnancy and in the postpartum period. It begins as erythematous plaques with pustules at their edges in the genito-inguinal and other flexural areas; the pustules are sterile and, while they spread outwards, those in the centre open, crust over and take on an impetigo-like appearance. Those spreading outwards lead to the development of exfoliative dermatitis. Rather than itching, the lesions burn and have an unpleasant smell. The picture may also be accompanied by systemic symptoms such as feeling generally unwell, fatigue, fever, chills, raised ESR, leucocytosis, nausea and vomiting. Death has rarely been encountered.
Seborrhoeic Dermatitis
It is an inflammatory and itchy disease usually located in the seborrhoeic areas of the skin, but its exact cause is not known. Its frequency in the population is around 1–3%.
It usually appears after puberty and lasts for many years with periods of worsening and improvement. The disease has a strong preference for the scalp and hairy areas and very often settles on the face, the middle of the chest and the back. Although its appearance may vary by region, the typical appearance is of greasy, rather large scales on a reddish-orange erythematous base.
In the aetiology of the disease, the most important factor on a predisposed background is Malassezia furfur. Although its onset is at puberty, when the sebaceous glands become active, its exact relationship with seborrhoea is not known. It increases and spreads with alcohol intake, intense emotional stress, atopy and many conditions in which the immune system is suppressed.
On the scalp, simple dandruff is the earliest and simplest sign of seborrhoeic dermatitis. This is followed by perifollicular erythema and redness, increased scaling, and merging and spreading of these areas. It can sometimes form thick layers on top of one another. As it becomes older it can spread over the whole scalp with larger, greasy scales. In chronic cases hair loss due to inflammation may be seen, but this is considered reversible. To what extent it affects androgenetic alopecia is not clear.
On the face there are finer scales on an erythematous base. The inner eyebrows, nose and cheeks are the most commonly involved areas. It is also common under the beard and moustache and regresses when the hair is shaved. Blepharitis is common, with red, scaly eyelid margins. There is erythema and typical scaling behind and inside the ears, and sometimes fissures may form in the fold.
On the trunk, particularly in men, it appears as sharply demarcated erythematous plaques with greasy scales in the middle of the chest and, less often, in the middle of the back; sometimes it may form circinate patterns like superficial fungal diseases. Rarely it occurs in the armpits and groin, where it can be misleading because it has no scales. In very rare cases generalised forms or an erythrodermic appearance may develop.
In the differential diagnosis it may be confused with diseases such as psoriasis, types of eczema, superficial fungal diseases and pityriasis rosea. All antimycotics effective against Malassezia furfur can be effective in treatment, but "ketoconazole" is the specific medicine. It is very good when used topically and can also be used systemically, but it has many side effects. Other imidazoles, ciclopirox olamine, terbinafine, selenium sulphide and zinc pyrithione are other effective medicines. Alcohol-based solutions should be avoided as they may cause irritation. Systemic itraconazole is also effective. Topical sulphur and tar are also effective, and recently benzoyl peroxide and lithium succinate have also been reported to be effective. Short-term topical steroids can be used only in very acute and severe types.
Lichen Planus
Lichen planus is an itchy skin disease that can last for years, mainly affecting the skin surface and the mucous membranes (such as the oral and genital mucosa), and more rarely the nails and hair. Lichen planus is not a form of cancer. It is not an infectious disease and is not contagious.
How is the disease treated?
There is no definitive treatment that completely eliminates lichen planus. However, the main aim in treating lichen planus, which is very itchy, is to relieve the itching and improve the patient’s clinical appearance until the disease runs its course. Because the pattern of involvement differs from patient to patient, there is no single treatment protocol. Treatment of lichen planus must always be planned by a dermatologist.
The medicines most often used in treating lichen planus include topical corticosteroid medicines and anti-itch tablets. In severe disease, immune-modulating medicines such as corticosteroid tablets, vitamin A derivatives and ultraviolet light treatments are used. In lichen planus, which is a long-lasting disease, skin care, avoiding trauma and follow-up are important. Do not deviate from your dermatologist’s recommendations, use your medicines regularly and do not miss your follow-up appointments.
Annular lichen planus: In lichen planus the papules are rarely completely ring-shaped. Annular lesions with atrophic centres may be found on the buccal mucosa.
Hypertrophic lichen planus: These lesions are extremely itchy. They are found particularly around the ankles and on the extensor surfaces of the lower limbs. Hypertrophic lesions are usually chronic; after the lesions heal, residual pigmentation and scarring may eventually remain.
Atrophic lichen planus: Atrophic lichen planus is characterised by ring-shaped hypertrophic lesions.
Actinic lichen planus: Also known as subtropical lichen planus, it occurs in regions such as Africa, the Middle East and India. These mildly itchy eruptions are usually seen on the nails, scalp and mucous membranes. The lesions are characterised by patches with a hypopigmented zone surrounding a hyperpigmented centre.
Lichen planus pigmentosus: This is a rare variant of lichen planus, but it may be seen more often in races with darkly pigmented skin, such as Latin Americans or Asians. It usually appears on the face and neck.
Lichen planus pemphigoides: This is a rare form of lichen planus. Lichen planus lesions develop after the blisters. Clinically, histopathologically and immunopathologically it has features of both lichen planus and bullous pemphigoid, but it has a better prognosis than pemphigoid.
Lichen Nitidus (Pinkus)
A chronic inflammatory disease characterised by shiny, flat-topped, mostly skin-coloured micropapules no bigger than a pinhead. In the early stages the lesions are localised, mainly on the lower abdomen, penis and inner thighs. As the disease progresses the distribution may become generalised.
Lichen Striatus
Lichen striatus, also known as linear lichenoid dermatosis or Blaschko linear dermatosis, is a rare, usually self-limiting inflammatory skin disease of unknown aetiology, most often seen in children. Its incidence is slightly higher in females than in males. It usually appears as linear violaceous papules on the limbs. Histopathology shows a lichenoid reaction that also involves the follicles and glands. Although the diagnosis is mainly clinical, it can be difficult to distinguish from other linear dermatoses such as blaschkitis and linear lichen planus, especially in adult patients. In this study, a case of adult-onset lichen striatus is presented in a 28-year-old woman who presented with linear erythematous papules extending from the ankle to the posteromedial leg. The findings that may be detected in cases of lichen striatus and the difficulties that may be encountered in diagnosis and differential diagnosis are discussed.
Pityriasis Rosea
Pityriasis rosea is a common skin condition, and its symptoms usually progress in three distinct stages. The first and second stages may be missed or may not occur in many patients.
The condition usually affects older children and adults aged 10–40, with peaks in the 25–30 age group. It is slightly more common in women, but the reason for this is unclear.
Elderly people over eighty and babies under 1 year of age are rarely affected. The exact cause of the condition is not known, but it is suspected that it may be caused by a viral infection.
The symptoms are described according to the stage of the condition.
Prodromal (early) symptoms of pityriasis rosea
These occur in fewer than half of affected individuals. In these individuals the symptoms may last for a week or so. They include:
- a high temperature or fever of 38ºC (100.4ºF) or above
- an upset stomach
- headache
- loss of appetite
- aching joints
- a general feeling of being unwell, known as malaise
Symptoms of the second stage of pityriasis rosea
The second stage is the start of the rash. It begins with a red, oval patch of scaly skin, 2 to 10 cm (0.8–4 inches) in size, called the "herald patch". It usually appears on the trunk, on the abdomen or chest.
Less commonly, the herald patch may occur at other sites such as the genitals, scalp or face. The herald patch gradually grows over the following days.
Generalised skin rash
After this, a generalised skin rash appears. This usually occurs from a few days to two weeks after the herald patch first appears.
This rash consists of small, raised, red patches 0.5–1.5 cm in size. They appear on the chest, abdomen, arms, legs (thighs), neck and so on. The face is usually not affected.
The patches are distributed in a typical ‘Christmas tree’ or V-shaped pattern on the upper back and chest. The rash extends down the sides in slanting triangular rows, giving the appearance of a pine or Christmas tree.
In patients with fair or light skin the rash looks pinkish or red. In people with dark skin these patches may look grey, dark brown or black. The rash is usually not painful, but it may be itchy in about three quarters of all cases.
In some people the itching may be mild, while others develop severely itchy lesions. The itching gets worse when the person is hot, sweating, wearing tight clothing or comes into contact with water.
Rarely, plaques, patches and ulcers may develop inside the mouth in some patients. Both the herald patch and the secondary rash usually clear within three months, or about 12 weeks. In some cases the symptoms persist for up to six months. After the rash has healed there may be darkening or lightening of the skin. This usually returns to normal without treatment within a few months. There is no scarring with pityriasis rosea.
When should you seek medical help?
Medical help should be sought if the itching is troublesome or interferes with sleep or daily activities.
Medical help should be sought immediately if:
- the symptoms have lasted for more than five months
- the rash covers the arms and legs but not the trunk
- the rash is spreading rapidly over the body
- the patches are leaking clear fluid, blood or pus
This is because these symptoms may indicate a rash other than pityriasis rosea.
Other skin conditions, such as psoriasis and the skin signs of syphilis, a sexually transmitted infection (STI), may need to be ruled out in this situation.
Pityriasis Lichenoides et Varioliformis Acuta
Pityriasis lichenoides et varioliformis acuta (PLEVA), also known as Mucha-Habermann disease, is a rare lymphoproliferative skin disease of unknown aetiology that most often affects children and young adults. Clinically it is characterised by erythematous, scaly papules, often accompanied by haemorrhagic and papulonecrotic lesions. Although the aetiology of PLEVA is unknown, the literature reports that medicines and infectious agents may be triggers. Foremost among these are upper respiratory tract infections. Systemic antibacterial agents, phototherapy and topical corticosteroids are used in treatment. Immunosuppressive or immunomodulatory agents are recommended only in the febrile ulceronecrotic form of the disease.
Prurigo Nodularis
Prurigo nodularis is a chronic skin disease characterised by severely itchy papules and nodules. Although lesions can form anywhere on the body, they are most often located on the extensor surfaces of the limbs, the face and the trunk. Psychological factors such as stress, depression and anxiety, as well as other psychiatric illnesses, play an important role in the onset of pruritic and psychosomatic diseases, including prurigo nodularis. The psychological factors in the aetiology of prurigo nodularis and the accompanying psychiatric illnesses are important because they make it necessary to focus the treatment approach mainly on psychotherapeutic approaches rather than on dermatological treatment alone.
Erythema Annulare Centrifugum
Although there are many diseases that present with red, ring-shaped rashes, one of the most common of these is erythema annulare centrifugum. Others are annular erythema, erythema gyratum repens, erythema gyratum perstans and erythema figuratum perstans.
What are the symptoms of the disease?
The rash can appear at any age. Usually a small pink spot slowly expands outwards and grows into a ring shape, with a pale centre. The ring expands by 2–5 mm a day, usually until it reaches 6–8 cm. Sometimes the rash may be half-ring shaped. Several rashes may be seen together. The rash is usually on the buttocks and legs but may also be seen on the face, trunk and arms. There may be mild itching, but usually there are no symptoms.
What causes erythema annulare centrifugum?
Often no cause for the rash is found. However, there may sometimes be an underlying disease. These include:
Bacterial, fungal and viral diseases (tuberculosis, sinusitis, candidiasis)
Medicines such as the antimalarials chloroquine and hydroxychloroquine, oestrogen and penicillin
Cancer (especially in the type called erythema gyratum repens, in which the findings resemble a wood-grain pattern)
Foods, especially blue cheese and tomatoes
Recurrent appendicitis
Some liver disorders
Some thyroid diseases
When the underlying disease resolves or the causative medicine is stopped, the condition regresses on its own.
How is erythema annulare centrifugum treated?
Erythema annulare centrifugum usually regresses on its own. The rash may last for several months or years. Treatment is usually not needed. However, topical corticosteroid creams are helpful if there is itching.
Wells Syndrome
Wells syndrome was first described by Wells in 1971 as recurrent granulomatous dermatitis with eosinophilia and was later named eosinophilic cellulitis. This rare dermatosis is characterised by itchy, erythematous, indurated, cellulitis-like plaques. Erythematous papules, nodules and bullae may develop. Although peripheral blood eosinophilia is present during active disease in about half of the cases reported in the literature, it is not required for diagnosis. Multiple recurrences are typically seen.
Histopathologically, the acute phase shows oedema in the dermis and an infiltrate rich in eosinophils. In the subacute phase, flame figures form through degranulation of eosinophils surrounding collagen bundles, and phagocytic histiocytes are then seen around the flame figures. There are no signs of vasculitis. Flame figures are characteristic of eosinophilic cellulitis but are not diagnostic. The diagnosis of Wells syndrome is based on typical clinical and histopathological findings. Most reported cases are adults. Fewer than twenty cases in children have been reported. There is no known racial or sex predilection. Lesions can develop anywhere on the body, but involvement of the face is rare. Systemic symptoms such as fever, malaise and arthralgia are seen in only a small proportion of patients. Bone marrow eosinophilia has been described in some cases. A case of eosinophilic cellulitis with recurrent leg lesions and its successful treatment is presented here.
Graft-versus-Host Disease
Graft-versus-host disease (GVHD) is a complex clinical syndrome leading to organ dysfunction as a result of a severe immunological reaction mediated by healthy T lymphocytes taken from the donor and given to the patient together with stem cells; it is considered the most important cause of mortality and morbidity after allogeneic stem cell transplantation (SCT). Chronic GVHD appears late (usually more than 3 months after SCT) and is the single main factor determining the long-term outcomes of SCT and quality of life. After allogeneic SCT it is the most important cause of mortality apart from late relapse. The risk of developing cGVHD within 2 years of transplantation is 50–60%, and the greatest risk factor is a history of previous acute GVHD. In patients with cGVHD, shiny, pinkish-silver, raised skin lesions known as a lichenoid rash are often seen at the beginning. In advanced cases, fibrosis of the skin and subcutaneous tissue, resulting restriction of joint movement, and dry eyes and mouth accompany the picture.