Skin Conditions: Lichen Planus, Erythema Multiforme, Tinea Versicolour, Psoriasis, and Ringworm

Lichen planus is an inflammatory skin condition that affects both cutaneous and mucosal surfaces. It is characterized by flat-topped plaques and papules with a purple hue and white striae. Topical steroids and immunomodulators are used to treat it, as it can increase the risk of squamous cell carcinoma if left untreated.

Erythema multiforme is a skin condition that presents with targetoid lesions with a central depression, usually starting on the acral extensor surfaces. It can be caused by medications, infections, or underlying conditions such as sarcoidosis and non-Hodgkin’s lymphoma.

Tinea versicolour, also known as pityriasis versicolor, is a fungal skin infection that causes pale or dark patches on the arms, neck, and trunk. It does not involve mucosal surfaces.

Psoriasis is an autoimmune chronic skin condition that presents with erythematous plaques with overlying grey scale on the extensor surfaces of extremities. It is not associated with intra-oral mucosal lesions.

Ringworm, also known as tinea corporis, is a fungal skin infection that causes erythematosus, scaly patches on the skin surface of the trunk, back, and extremities. It is not usually seen on the scalp, groin, palms, and soles. The patches progressively enlarge and worsen, and can lead to the formation of pustules or vesicles. Following central resolution, the lesions can remain annular.

Differentiating Skin Conditions: A Brief Overview

Psoriasis is a skin condition characterized by a rash with typical histology and location. The Koebner phenomenon, where lesions occur at sites of trauma, is a common feature of psoriasis. Treatment involves exposure to ultraviolet light, tar-based treatments, and immunosuppressant drugs. Pruritus is not always present.

Seborrhoeic dermatitis presents as itchy, ill-defined erythema and greasy scaling on the scalp, nasolabial folds, or post-auricular skin in adults and adolescents.

Lichen planus is characterized by flat-topped, pruritic, polygonal, red-to-violaceous papules or plaques. Lesions are often located on the wrist, with papules demonstrating central dimpling.

Atopic dermatitis is a chronic inflammatory skin disease characterized by itchy, red rashes often found in the flexor areas of joints.

Tinea corporis is a ringworm infection characterized by expanding patches with central clearing and a well-defined active periphery. The active periphery is raised, pruritic, moist, erythematosus, and scaly, with papules, vesicles, and pustules.

Common Skin Infections and Conditions

Carbuncles, cellulitis, furuncles, infected sebaceous cysts, and necrotising fasciitis are all common skin infections and conditions that can cause discomfort and pain. Carbuncles are collections of pus that discharge to the surface via multiple sinuses and are usually caused by staphylococcal infection. Cellulitis is a bacterial infection of the lower dermis and subcutaneous tissue, presenting with a localised area of painful, red, swollen skin and fever. Furuncles are perifollicular abscesses, also typically caused by staphylococcal infection. Infected sebaceous cysts are round, dome-shaped, encapsulated lesions containing fluid or semi-fluid material. On the other hand, necrotising fasciitis is a serious bacterial infection of the soft tissue and fascia that can result in extensive tissue loss and death if not promptly recognised and treated with antibiotics and debridement. It is important to seek medical attention if any of these conditions are suspected, especially in patients with diabetes or those who are immunosuppressed. Clinical assessment and appropriate diagnostic tests should be conducted to ensure proper treatment and management.

Bullous Pemphigoid

Bullous pemphigoid is a skin condition that is characterized by the presence of tense bullae, which are filled with clear fluid and appear on normal or erythematosus skin. Unlike pemphigus vulgaris, which causes blisters at the dermal-epidermal junction, bullous pemphigoid causes blistering at the subepidermal level, resulting in the formation of tense blisters. In contrast, pemphigus vulgaris causes thin-walled and fragile blisters that are rarely intact.

To differentiate bullous pemphigoid from other skin conditions, such as pemphigus vulgaris, a skin biopsy for routine and direct immunofluorescence is necessary. This test helps to identify the presence of linear basement membrane zone deposition of immunoglobulin and complement, which are of the IgG type.

In summary, bullous pemphigoid is a skin condition that causes the formation of tense bullae on normal or erythematosus skin. It is important to differentiate it from other skin conditions, such as pemphigus vulgaris, through a skin biopsy for routine and direct immunofluorescence.

Differentiating Skin Rashes: A Comparison of Erythema Nodosum, Erythema Multiforme, Kaposi’s Sarcoma, Tinea Corporis, and Steven-Johnson’s Syndrome

Erythema nodosum is a rash characterized by painful red papules caused by inflammation of the subcutaneous fat. It is commonly seen on the extensor surfaces of the lower limbs and can be linked to various conditions such as streptococcal and tuberculous infection, inflammatory bowel disease, lymphoma, drug-related causes, and sarcoidosis.

Erythema multiforme, on the other hand, presents with typical target lesions on the extremities. It is an uncommon condition that can be mistaken for other skin rashes.

Kaposi’s sarcoma is an AIDS-defining malignancy caused by human herpes virus 8. It appears as red/purple papules on the skin or mucosal surfaces. However, the description of the rash, normal blood results, and an otherwise healthy patient make this diagnosis unlikely.

Tinea corporis, also known as ringworm, is a fungal infection transmitted from common pets or human-to-human. It presents as an erythematosus, scaly ring-like rash with central clearing.

Steven-Johnson’s syndrome is a severe form of erythema multiforme with multiple erythematosus macules on the face and trunk, epidermal detachment, and mucosal ulceration. It is a rare condition that can cause significant morbidity and mortality.

In summary, differentiating between these skin rashes is crucial for proper diagnosis and treatment. A thorough evaluation of the patient’s medical history, physical examination, and laboratory tests can help identify the underlying cause of the rash.

Napkin Rash: Causes and Treatment

Napkin rash, also known as nappy rash, is a common skin condition that affects infants. It is caused by a variety of factors, including contact dermatitis, bacterial and fungal infections, psoriasis, and atopic dermatitis. The condition is often exacerbated by the presence of infantile eczema, but it is not more common in boys or less common in soy-fed infants.

The primary cause of napkin rash is contact dermatitis, which occurs when the skin comes into contact with ammonia from urine. This can cause burning and irritation, leading to a rash. Infection with bacteria and Candida yeasts can also cause nappy rash, as can psoriasis and atopic dermatitis affecting the nappy area. Infection is often superimposed, making the condition more severe.

Prevention is the best treatment for napkin rash. Frequent nappy changing and fluid feeding early in the day can help lessen night-time urination, reducing the risk of contact dermatitis. Anti-fungal lotions may also be useful in treating the condition. By the causes and treatment options for napkin rash, parents can help their infants avoid this uncomfortable and painful condition.

Managing Eczema in Children: Treatment Options and Referral Considerations

When a child presents with eczema, the first step is often to use emollient cream to manage the symptoms. However, if the eczema persists or worsens, a topical corticosteroid cream may be necessary. It is important to use this sparingly and in conjunction with emollients. While oral corticosteroids may be considered in severe cases, they should be used with caution and ideally under the guidance of a dermatologist. Emollient ointments may also be helpful, but a short course of topical corticosteroids is often more effective for managing flare-ups. If symptoms continue to worsen despite treatment, referral to a dermatology clinic may be necessary. Watchful waiting is not appropriate in this situation.

Common Skin Infections and their Causes

Acne vulgaris is a prevalent skin condition among adolescents and young adults, particularly men. Hormonal changes stimulate the sebaceous glands to produce more sebum, leading to the formation of open comedones, which are inflamed follicles with a central dark plug of keratin. Propionibacterium acnes is responsible for breaking down complex lipids in sebum into free fatty acids, which cause inflammation of hair follicles. Treatment with antibiotics and 13-cis-retinoic acid can alleviate the symptoms of acne vulgaris.

Molluscum contagiosum is caused by the poxvirus, which leads to epidermal hyperplasia and ellipsoid molluscum bodies in the stratum corneum.

Impetigo is a bacterial infection of the skin caused by Staphylococcus aureus. It is highly contagious and often affects healthy children. The infection starts as a reddened macule and progresses to multiple serum-filled pustules that rupture and form a yellowish crust.

Papillomavirus causes warts or verrucae, which are common on the hands. They appear as several papules with a rough, irregular surface.

Tinea versicolor is caused by Malassezia furfur, a fungus that causes superficial fungal infections in the skin. Other forms of tinea are also caused by fungal infections.

Livedo Reticularis

Livedo reticularis is a skin condition characterized by a net-like pattern of blue or purple discoloration on the skin. This occurs due to the dilation of capillary blood vessels and the stagnation of blood within these vessels. The condition is more pronounced in cold weather and is commonly found on the legs, arms, and trunk.

Livedo reticularis can be idiopathic, meaning it has no known cause, or it can be secondary to other conditions such as malignancy, vasculitis, SLE, or cholesterol embolization. The condition is caused by the accumulation of blood in the capillaries, which leads to the discoloration of the skin.

In summary, livedo reticularis is a skin condition that causes a net-like pattern of blue or purple discoloration on the skin. It is caused by the accumulation of blood in the capillaries and can be idiopathic or secondary to other conditions. The condition is more pronounced in cold weather and is commonly found on the legs, arms, and trunk.

Medications and Psoriasis: Which Drugs to Avoid

Psoriasis is a chronic skin condition that can be triggered by various factors, including stress, infection, and certain medications. While sunlight can help alleviate psoriasis symptoms in most patients, it can worsen the condition in some individuals. Among the drugs that can exacerbate psoriasis are β blockers, antimalarials, lithium, and interferons. Therefore, if possible, people with psoriasis should avoid taking these medications. However, drugs such as clopidogrel, glyceryl trinitrate spray, low-molecular-weight heparin, and statins are not known to cause psoriasis flares. It is important to consult with a healthcare provider before taking any medication if you have psoriasis.

Common Skin Conditions: Acne Rosacea, Systemic Lupus Erythaematosus, Seborrhoeic Dermatitis, Acne Vulgaris, and Nodulocystic Acne

Skin conditions can be a source of discomfort and embarrassment for many people. Here are five common skin conditions and their features:

Acne Rosacea is a chronic rash that affects the central face, typically in those aged 30 to 60. Symptoms include facial flushing, telangiectasia, rhinophyma, papules, and pustules. Treatment options include topical metronidazole and oral antibiotics.

Systemic Lupus Erythaematosus is an autoimmune disorder that can affect various organs, including the skin. Common dermatological signs include a butterfly malar rash and discoid lupus.

Seborrhoeic Dermatitis is a chronic or relapsing form of eczema that mainly affects the scalp, face, and upper trunk. Symptoms include indurated hyperpigmented plaques and creases around the nose, behind ears, and within eyebrows.

Acne Vulgaris is a common variety of acne that affects the pilosebaceous unit. It is most common in young adults with high levels of sex hormones and is graded according to the number of comedones and inflammatory lesions seen.

Nodulocystic Acne is a severe form of acne that affects the face, chest, and back, mainly in men. Symptoms include multiple inflamed and uninflamed nodules and scars.

Pemphigoid: A Skin Condition Caused by Furosemide

Pemphigoid is a skin condition that typically affects elderly individuals, presenting as tense blisters on the arms and legs. The use of furosemide, a diuretic, is a common cause of this condition. While other diuretics can also cause pemphigoid, it is a rarer occurrence. A positive immunofluorescence test confirms the diagnosis, and treatment with steroids is usually successful.

It is important to differentiate pemphigoid from pemphigus, which presents in younger age groups and causes flaccid blisters that easily erupt, leading to widespread lesions. Overall, recognizing the signs and symptoms of pemphigoid and identifying its underlying cause can lead to effective treatment and management of this skin condition.

Common Skin Infections and Their Causes

Molluscum contagiosum is a viral infection that spreads through direct contact and causes pink papules with a central umbilicus. The lesions contain cheese-like material and can be treated with cryotherapy or imiquimod.

Cellulitis is a bacterial infection that affects the lower dermis and subcutaneous tissue, causing red, swollen, and painful skin. It is commonly caused by Streptococcus pyogenes and Staphylococcus aureus.

Folliculitis is an inflammation of the hair follicles, often caused by staphylococcal infections.

Impetigo is a bacterial infection that results in pustules and honey-colored, crusted erosions. It is commonly caused by S. aureus.

Necrotizing fasciitis is a severe bacterial infection that affects soft tissue and fascia. The bacteria release toxins and enzymes that lead to thrombosis and destruction of soft tissue and fascia. Bacterial causes include S. aureus and Clostridium perfringens, among others.

Overview of Common Skin Infections and Their Causes

Investigating Pruritus in a Male Patient

Pruritus, or itching, can be a symptom of various underlying conditions. In the case of a male patient without apparent cause of pruritus, an HIV antibody test would be the most appropriate first-line investigation, along with other tests such as blood sugar, thyroid profile, and urea and electrolytes. This is because HIV infection can present with intractable pruritus before other symptoms appear. Allergen skin tests may be used in suspected allergic reactions, but they would be inappropriate in this case as there is no indication of such a reaction. The anti-M2 antibody test is used for primary biliary cirrhosis, which is a rare possibility in this case. A chest x-ray is not a useful first-line test as there is no indication of malignancy. Kidney diseases can give rise to pruritus, but there is no mention of kidney disease here. It is important to consider the patient’s medical history, including any potential risk factors such as IV drug abuse, which may be the source of infection. Further investigations may be necessary depending on the results of initial tests.

The patient’s nail signs suggest a diagnosis of clubbing, which is commonly seen in various internal conditions such as cardiac issues like infective endocarditis and cyanotic congenital heart disease, respiratory problems like bronchial cancer, tuberculosis, sarcoidosis, cystic fibrosis, and pulmonary fibrosis, gastrointestinal issues like inflammatory bowel disease, biliary cirrhosis, and malabsorption, and other conditions like thyroid acropachy. The presence of Osler’s nodes, painful nodules caused by immune complex deposition, further supports a diagnosis of infective endocarditis, which is commonly associated with this symptom. Although the patient has a history of potential asbestos exposure, the history of heart valve replacement, current symptoms, and nail signs point towards infective endocarditis as the likely diagnosis. Other conditions like inflammatory bowel disease, pulmonary fibrosis, sarcoidosis, and tuberculosis can cause clubbing but not Osler’s nodes.

Common Skin Conditions and Associated Antibodies

Lichen Planus: This skin condition is associated with viral hepatitis, specifically hepatitis B and C. Antibodies may indicate the presence of hepatitis and other conditions such as erythema multiforme, urticaria, polyarteritis nodosa, cryoglobulinemia, and porphyria cutanea tarda.

Chronic Hepatitis B: A negative anti-HBc antibody status suggests that the patient has not been exposed to the hepatitis B virus. A positive anti-HBs antibody status may indicate vaccination.

Dermatitis Herpetiformis: This condition is characterized by extremely itchy papulovesicles on the elbows, knees, upper back, and buttocks. It is often associated with gluten-sensitive enteropathy. Autoantibodies such as anti-gliadin, anti-endomysial, and anti-tissue transglutaminase may be present.

Essential Mixed Cryoglobulinemia: This condition presents with palpable purpura and arthritis, among other signs of systemic vasculitis. It is also associated with hepatitis C virus infection, and rheumatoid factor is usually positive.

Dermatomyositis: Gottron’s papules, which are violet, flat-topped lesions, are associated with dermatomyositis and the anti-Jo-1 autoantibody. They are typically seen over the metacarpophalangeal or interphalangeal joints.

Skin Conditions and Their Antibody Associations

Cutaneous Larva Migrans and Other Skin Conditions: A Differential Diagnosis

Cutaneous larva migrans is a common skin condition caused by the migration of nematode larvae through the skin. It is typically found in warm sandy soils and can be diagnosed based on the history and appearance of serpiginous lesions. Treatment involves the use of thiobendazole. Other skin conditions, such as impetigo, tinea pedis, and photoallergic dermatitis, have different causes and presentations and are less likely to be the correct diagnosis. Larva currens, caused by Strongyloides stercoralis, is another condition that can cause itching and skin eruptions, but it is typically associated with an intestinal infection and recurrent episodes. A differential diagnosis is important to ensure proper treatment and management of these skin conditions.

Skin Conditions Associated with Various Diseases

Pyoderma gangrenosum is a skin condition associated with Crohn’s disease. It is diagnosed based on clinical history and examination, and treatment options include topical or systemic steroid therapy. Coeliac disease is not associated with pyoderma gangrenosum, but is linked to dermatitis herpetiformis, which causes itchy papules on the scalp, shoulders, buttocks, or knees. Pretibial myxoedema is a skin condition associated with Grave’s disease, characterized by waxy, discolored induration on the Pretibial areas. SLE is not associated with pyoderma gangrenosum, but is linked to a facial butterfly rash. T1DM is not associated with pyoderma gangrenosum, but is linked to necrobiosis lipoidica and granuloma annulare, which cause tender patches and discolored plaques, respectively.

Treatment Options for Localised Plaque Psoriasis

Localised plaque psoriasis is a chronic skin condition that causes red, scaly patches on the skin. There are several treatment options available, including Dovobet®, Infliximab, Methotrexate, Photochemotherapy (PUVA), and Retinoids.

Dovobet® is an ointment or gel that contains both calcipotriol and betamethasone dipropionate. It works synergistically to relieve the symptoms of localised plaque psoriasis. However, it is contraindicated for patients with certain conditions and precautions should be taken in prescribing for certain patients.

Infliximab is an anti-TNF alpha biologic agent that is used in systemic arthritis, particularly psoriatic arthritis. It is not used for localised plaque psoriasis.

Methotrexate is an antifolate immunosuppressant and chemotherapy agent. It would not be a first-line therapy for localised psoriasis.

Photochemotherapy (PUVA) is a type of ultraviolet radiation treatment that can be used for localised psoriasis but would not be first line.

Retinoids are derived from vitamin A and cause proliferation and reduced keratinisation of skin cells. They would not be first line for localised psoriasis.

In conclusion, the choice of treatment for localised plaque psoriasis depends on the severity of the condition, the patient’s medical history, and other factors. It is important to consult with a healthcare professional to determine the best course of treatment.

Common Skin Conditions: Causes, Symptoms, and Treatments

Acne Rosacea:
Acne rosacea is a chronic skin condition that typically affects women and people with fair skin between the ages of 30-50. The exact cause is unknown, but environmental factors such as alcohol, caffeine, heat, and stress can aggravate the condition. Symptoms include a persistent erythematosus rash on the face, particularly over the nose and cheeks, with associated telangiectasia. Treatment involves lifestyle modifications and pharmacological interventions with topical or oral antibiotics.

Acne Vulgaris:
Acne vulgaris is an inflammatory response to Propionibacterium acnes, a normal skin commensal. It commonly affects adolescents and presents with a variety of lesions ranging from comedones to cysts and scars. It predominantly affects areas with high concentrations of sebaceous glands, such as the face, back, and chest.

Discoid Lupus Erythematosus:
Discoid lupus erythematosus is a cutaneous form of lupus erythematosus that affects sun-exposed areas of the skin. It typically presents in women between the ages of 20-40 and presents as red patches on the nose, face, back of the neck, shoulders, and hands. If left untreated, it can cause hypertrophic, wart-like scars.

Pityriasis Rosea:
Pityriasis rosea is a self-limiting skin condition that affects young adults, mostly women. It presents with salmon-pink, flat or slightly raised patches with surrounding scale known as a collarette. The rash is usually symmetrical and distributed predominantly on the trunk and proximal limbs.

Psoriasis:
Psoriasis is an autoimmune skin condition that presents with red scaly patches on the extensor surfaces of the limbs and behind the ears. Treatment involves topical or systemic medications to control symptoms and prevent flares.