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

Lichen Planus: A skin condition that affects cutaneous and mucosal surfaces, characterised by flat-topped plaques and papules with a purple hue and white striae. It can be treated with topical steroids and immunomodulators.

Erythema Multiforme: A skin condition characterised by targetoid lesions with a central depression, usually starting on the acral extensor surfaces and progressing to involve the trunk and back. It can be caused by medications, infections, or underlying conditions.

Psoriasis: An autoimmune chronic skin condition presenting with erythematous plaques and greyscale on the extensor surfaces of extremities. It is not associated with intra-oral mucosal lesions.

Ringworm: A fungal skin infection characterised by erythematous, scaly patches on the skin surface of the trunk, back, and extremities. It can lead to the formation of pustules or vesicles.

Tinea Versicolor: A fungal skin infection characterised by pale or dark, copper-coloured patches on the arms, neck, and trunk. It does not involve mucosal surfaces.

Understanding Different Skin Conditions

Skin cancer can take on different forms, including basal cell carcinoma (BCC), actinic keratosis, herpes zoster infection, melanoma, and squamous cell carcinoma (SCC). BCCs can appear on any part of the body and often produce a bloody crust. AKs are scaly or hyperkeratotic lesions that can become malignant and are common in individuals over 60 years old. Herpes zoster infection causes a rash that is usually unilateral and follows a dermatomal distribution. Melanoma is a malignant tumour that arises from cutaneous melanocytes and can take on different types. SCC is the second most common type of skin cancer and arises from the keratinocytes of the epidermis. It predominantly affects sun-exposed sites and has a firm, indurated appearance with surrounding inflammation. BCCs are commonly found in sun-exposed areas and have a pearly appearance with rolled edges and surrounding telangiectasia. Management for skin cancer varies depending on the type and severity, but removal through curettage or excision is common for BCCs.

Milia, which are often found on the face of newborns, are a normal occurrence and can be seen in up to 50% of babies. They typically disappear on their own within a few weeks.

Understanding Milia: Small, Benign Cysts on the Face

Milia are small cysts that are filled with keratin and are typically found on the face. These cysts are benign and are not harmful to one’s health. Although they can appear at any age, they are more commonly found in newborns. Milia are often described as small, white bumps that are painless and do not cause any discomfort.

While the exact cause of milia is unknown, they are thought to occur when dead skin cells become trapped in the skin’s surface. They can also develop as a result of using heavy skin care products or as a side effect of certain medications. In most cases, milia will disappear on their own without any treatment. However, if they persist or become bothersome, a dermatologist may recommend treatment options such as extraction or chemical peels.

To prevent the sebaceous cyst from recurring, it is necessary to surgically remove the entire structure. This can be done by a general practitioner or a surgical team, but funding for the procedure may be limited due to its lower clinical priority. Patients may opt to have the surgery done privately. Incision and drainage or fine needle aspiration may provide temporary relief, but the cyst is likely to return. Intralesional steroids are not recommended in this case, as there is no infection present. Oral antibiotics are also unnecessary. Complete surgical excision offers the best chance for long-term resolution of the patient’s symptoms.

Understanding Sebaceous Cysts

Sebaceous cysts refer to a group of cysts that include both epidermoid and pilar cysts. However, the term is not entirely accurate and should be avoided if possible. Epidermoid cysts occur when there is an overgrowth of epidermal cells in the dermis, while pilar cysts, also known as trichilemmal cysts or wen, originate from the outer root sheath of the hair follicle. These cysts can appear anywhere on the body, but are most commonly found on the scalp, ears, back, face, and upper arm, and will typically have a punctum.

To prevent recurrence, it is essential to remove the entire cyst wall during excision. While sebaceous cysts are generally harmless, they can become infected and cause discomfort or pain.

Understanding Autoimmune Blistering Conditions: Pemphigus Vulgaris and Bullous Pemphigoid

Pemphigus Vulgaris: Autoimmune Blistering Condition

Pemphigus vulgaris is an autoimmune blistering condition that primarily affects middle-aged patients. The condition is caused by Immunoglobulin G (IgG) autoantibodies against desmosomal components (desmogleins 1 and 3) of the superficial layers of the skin. This results in flaccid blisters that rupture easily, leading to erosions and scarring. The oral mucosa is often affected early, and Nikolsky’s sign is positive. Immunofluorescence reveals intra-epidermal circular deposits, and antibodies against desmosomes are usually positive. The condition requires aggressive treatment, with high-dose steroids initially used, and life-long maintenance doses often needed. Immunologicals are being trialled.

Bullous Pemphigoid: Another Autoimmune Blistering Condition

Bullous pemphigoid is another autoimmune blistering condition that typically affects older patients. The condition is caused by antibodies directed to the deeper basement membrane of the skin. This results in tense, firm, often haemorrhagic blisters that do not rupture easily. Oral lesions are rare, and Nikolsky’s sign is negative. Immunofluorescence reveals linear IgG and C3 deposits along the basement membrane of the skin, and antibodies against hemidesmosomes may be positive. The condition carries significantly less morbidity than pemphigus vulgaris, and topical steroid cream (ex: clobetasol propionate usually suffices).

No Link to Other Conditions

There is no link between pemphigus vulgaris or bullous pemphigoid and other conditions such as alopecia, positive HIV serology, or psoriasis. It is important to understand the differences between these autoimmune blistering conditions to ensure proper diagnosis and treatment.

Keratoacanthoma is a benign lesion, but urgent excision is advised due to difficulty in clinically excluding squamous cell carcinoma.

Understanding Keratoacanthoma

Keratoacanthoma is a type of non-cancerous tumor that affects the epithelial cells. It is more commonly found in older individuals and is rare in young people. The tumor is characterized by a dome-shaped papule that resembles a volcano or crater. As it grows, it becomes filled with keratin and develops a central crater. While spontaneous regression of keratoacanthoma is common within three months, it often results in scarring. Therefore, it is important to urgently remove such lesions as it is difficult to clinically differentiate them from squamous cell carcinoma. Removal may also prevent scarring.

Scarring alopecia can be caused by various factors such as trauma/burns, radiotherapy, discoid lupus, tinea capitis, and lichen planus. However, out of these options, lichen planus is the only cause that leads to scarring alopecia. The remaining causes, including alopecia areata, carbimazole, trichotillomania, and telogen effluvium, result in non-scarring alopecia.

Input:
Alopecia may be divided into scarring (destruction of hair follicle) and non-scarring (preservation of hair follicle). Scarring alopecia can be caused by trauma, burns, radiotherapy, lichen planus, discoid lupus, and untreated tinea capitis. Non-scarring alopecia can be caused by male-pattern baldness, drugs such as cytotoxic drugs, carbimazole, heparin, oral contraceptive pill, and colchicine, nutritional deficiencies such as iron and zinc deficiency, autoimmune conditions such as alopecia areata, telogen effluvium, hair loss following a stressful period such as surgery, and trichotillomania.

Output:
– Alopecia can be categorized into scarring and non-scarring types.
– Scarring alopecia is caused by trauma, burns, radiotherapy, lichen planus, discoid lupus, and untreated tinea capitis.
– Non-scarring alopecia is caused by male-pattern baldness, drugs such as cytotoxic drugs, carbimazole, heparin, oral contraceptive pill, and colchicine, nutritional deficiencies such as iron and zinc deficiency, autoimmune conditions such as alopecia areata, telogen effluvium, hair loss following a stressful period such as surgery, and trichotillomania.

Molluscum Contagiosum: Myths and Facts

Molluscum contagiosum is a common skin infection caused by a poxvirus. However, there are several myths surrounding this condition that need to be debunked. Firstly, it is not true that the condition resolves spontaneously. While most cases do clear up on their own within 6-9 months, some can last up to 4 years. Secondly, molluscum contagiosum is highly infectious and can be transmitted through contact with infected persons or objects, including swimming pools. Sexual transmission is also possible.

Another myth is that patients can treat themselves by squeezing the spots. This is not recommended as it can lead to scarring. Additionally, molluscum contagiosum is not limited to children. While it does present mainly in young children, there is also a later peak in young adults, some of which is attributable to sexual transmission.

Finally, piercing the lesions with an orange stick dipped in phenol is not the treatment of choice. In fact, the condition usually requires no treatment and resolves on its own. Treatment may be recommended for adults or older children with particularly unsightly spots or in the immunosuppressed, where it can take several years to resolve. Topical applications such as benzyl peroxide or potassium hydroxide, as well as curettage and cryotherapy, can be used to treat the condition.

In conclusion, it is important to separate fact from fiction when it comes to molluscum contagiosum. While it is a common and often harmless condition, it is important to seek medical advice if you have concerns or if the spots are causing discomfort or affecting your quality of life.

The tear-drop scaly papules that have suddenly appeared on the patient’s trunk and limbs suggest guttate psoriasis. This type of psoriasis is commonly seen in children and young adults who have recently had a Streptococcus infection, such as the tonsillitis infection that this patient had. The rash is characterized by multiple small scaly and red patches that have a teardrop shape.

Disseminated varicella zoster, pityriasis rosea, and pityriasis versicolor are not likely diagnoses for this patient. Disseminated varicella zoster causes a different type of rash that includes macular, papular, and vesicular lesions that crust over time. Pityriasis rosea presents with a large round herald patch on the chest, abdomen, or back, and is thought to be triggered by viral or bacterial infections. Pityriasis versicolor is a fungal infection that causes patches that are paler than the surrounding skin, and is commonly found on the upper limbs and neck. However, exposure to heat and moisture can increase the risk of developing this rash.

Guttate psoriasis is a type of psoriasis that is more commonly seen in children and adolescents. It is often triggered by a streptococcal infection that occurred 2-4 weeks prior to the appearance of the lesions. The name guttate comes from the Latin word for drop, as the lesions appear as small, tear-shaped papules on the trunk and limbs. These papules are pink and scaly, and the onset of the condition is usually acute, occurring over a few days.

In most cases, guttate psoriasis will resolve on its own within 2-3 months. There is no clear evidence to support the use of antibiotics to treat the underlying streptococcal infection. Treatment options for guttate psoriasis include topical agents commonly used for psoriasis and UVB phototherapy. In cases where the condition recurs, a tonsillectomy may be necessary.

It is important to differentiate guttate psoriasis from pityriasis rosea, another skin condition that can present with similar symptoms. Guttate psoriasis is often preceded by a streptococcal sore throat, while pityriasis rosea may be preceded by a respiratory tract infection. The appearance of guttate psoriasis is characterized by tear-shaped papules on the trunk and limbs, while pityriasis rosea presents with a herald patch followed by multiple oval lesions with a fine scale. While guttate psoriasis resolves within a few months, pityriasis rosea typically resolves after around 6 weeks.

Acne vulgaris is a common skin condition that typically affects adolescents, with the face, neck, and upper trunk being the most commonly affected areas. It is characterized by the obstruction of hair follicles with keratin plugs, leading to the formation of comedones, inflammation, and pustules. The severity of acne can be classified as mild, moderate, or severe, depending on the presence and extent of inflammatory lesions, papules, and pustules.

The management of acne vulgaris typically involves a step-up approach, starting with single topical therapy such as topical retinoids or benzoyl peroxide. If this is not effective, topical combination therapy may be used, which includes a topical antibiotic, benzoyl peroxide, and topical retinoid. Oral antibiotics such as tetracyclines may also be prescribed, but they should be avoided in pregnant or breastfeeding women and children under 12 years of age. Erythromycin may be used in pregnancy, while minocycline is now considered less appropriate due to the possibility of irreversible pigmentation. Oral antibiotics should be used for a maximum of three months and always co-prescribed with a topical retinoid or benzoyl peroxide to reduce the risk of antibiotic resistance.

Combined oral contraceptives (COCP) are an alternative to oral antibiotics in women, and Dianette (co-cyrindiol) may be used as it has anti-androgen properties. However, it has an increased risk of venous thromboembolism compared to other COCPs, so it should generally be used second-line and for only three months. Oral isotretinoin is a potent medication that should only be used under specialist supervision, and it is contraindicated in pregnancy. Finally, there is no evidence to support dietary modification in the management of acne vulgaris.

Blistering is not a characteristic of polymorphic eruption of pregnancy.

Skin Disorders Associated with Pregnancy

During pregnancy, women may experience various skin disorders. The most common one is atopic eruption of pregnancy, which is characterized by an itchy red rash. This condition does not require any specific treatment. Another skin disorder is polymorphic eruption of pregnancy, which is a pruritic condition that usually appears during the last trimester. The lesions often first appear in abdominal striae, and management depends on the severity of the condition. Emollients, mild potency topical steroids, and oral steroids may be used. Pemphigoid gestationis is another skin disorder that causes pruritic blistering lesions. It usually develops in the peri-umbilical region and later spreads to the trunk, back, buttocks, and arms. This condition is rarely seen in the first pregnancy and usually presents in the second or third trimester. Oral corticosteroids are usually required for treatment.

Understanding Bullous Pemphigoid

Bullous pemphigoid is an autoimmune disease that causes blistering of the skin due to the development of antibodies against hemidesmosomal proteins BP180 and BP230. This condition is more common in elderly patients and is characterized by itchy, tense blisters that typically appear around flexures. However, the blisters usually heal without scarring, and there is usually no mucosal involvement.

To diagnose bullous pemphigoid, a skin biopsy is necessary, and immunofluorescence shows IgG and C3 at the dermoepidermal junction. Treatment for this condition involves referral to a dermatologist for biopsy and confirmation of diagnosis, as well as the use of oral corticosteroids as the mainstay of treatment. Topical corticosteroids, immunosuppressants, and antibiotics may also be used.

It is worth noting that while mucosal involvement is seen in some patients, it is not a classic feature of bullous pemphigoid and is therefore not always mentioned in exam questions. Overall, understanding the symptoms, diagnosis, and treatment of bullous pemphigoid is crucial for healthcare professionals to provide appropriate care for patients with this condition.

Tear-drop scaly papules suddenly appearing on the trunk and limbs may indicate guttate psoriasis.

Guttate psoriasis is a type of psoriasis that is more commonly seen in children and adolescents. It is often triggered by a streptococcal infection that occurred 2-4 weeks prior to the appearance of the lesions. The name guttate comes from the Latin word for drop, as the lesions appear as small, tear-shaped papules on the trunk and limbs. These papules are pink and scaly, and the onset of the condition is usually acute, occurring over a few days.

In most cases, guttate psoriasis will resolve on its own within 2-3 months. There is no clear evidence to support the use of antibiotics to treat the underlying streptococcal infection. Treatment options for guttate psoriasis include topical agents commonly used for psoriasis and UVB phototherapy. In cases where the condition recurs, a tonsillectomy may be necessary.

It is important to differentiate guttate psoriasis from pityriasis rosea, another skin condition that can present with similar symptoms. Guttate psoriasis is often preceded by a streptococcal sore throat, while pityriasis rosea may be preceded by a respiratory tract infection. The appearance of guttate psoriasis is characterized by tear-shaped papules on the trunk and limbs, while pityriasis rosea presents with a herald patch followed by multiple oval lesions with a fine scale. While guttate psoriasis resolves within a few months, pityriasis rosea typically resolves after around 6 weeks.

Acne vulgaris is a common skin condition that typically affects adolescents, with the face, neck, and upper trunk being the most commonly affected areas. It is characterized by the obstruction of hair follicles with keratin plugs, leading to the formation of comedones, inflammation, and pustules. The severity of acne can be classified as mild, moderate, or severe, depending on the presence and extent of inflammatory lesions, papules, and pustules.

The management of acne vulgaris typically involves a step-up approach, starting with single topical therapy such as topical retinoids or benzoyl peroxide. If this is not effective, topical combination therapy may be used, which includes a topical antibiotic, benzoyl peroxide, and topical retinoid. Oral antibiotics such as tetracyclines may also be prescribed, but they should be avoided in pregnant or breastfeeding women and children under 12 years of age. Erythromycin may be used in pregnancy, while minocycline is now considered less appropriate due to the possibility of irreversible pigmentation. Oral antibiotics should be used for a maximum of three months and always co-prescribed with a topical retinoid or benzoyl peroxide to reduce the risk of antibiotic resistance.

Combined oral contraceptives (COCP) are an alternative to oral antibiotics in women, and Dianette (co-cyrindiol) may be used as it has anti-androgen properties. However, it has an increased risk of venous thromboembolism compared to other COCPs, so it should generally be used second-line and for only three months. Oral isotretinoin is a potent medication that should only be used under specialist supervision, and it is contraindicated in pregnancy. Finally, there is no evidence to support dietary modification in the management of acne vulgaris.

Understanding Topical Treatments for Skin Conditions

Athlete’s foot is a common fungal infection that affects the toe webs and is often caused by excess moisture. The first-line treatment for this condition is a topical antifungal such as miconazole or terbinafine cream, which should be used twice daily for four weeks. If there is no improvement, further investigations may be required, and oral antifungals may be prescribed. It is important to advise patients on foot hygiene and to avoid walking barefoot in communal areas.

Dithranol is a topical treatment for psoriasis, a condition that presents as large, scaly plaques with a symmetrical distribution. This is different from athlete’s foot, which is characterized by a moist, peeling rash between the toes. Emollients, which are topical moisturizers, are used for atopic eczema management and have no role in treating athlete’s foot.

Oral terbinafine is reserved for severe or extensive fungal infections that cannot be treated with topical antifungal agents. Finally, while an antifungal/topical steroid combination may reduce symptoms more rapidly in cases of inflamed tissue, it has no overall benefit. Moderately potent topical steroids such as eumovate are more appropriate for managing atopic eczema.

The recommended treatment for venous ulceration is compression bandaging, which is appropriate for this patient who exhibits typical signs of the condition such as hyperpigmentation and an ulcer located above the medial malleolus. Before initiating compression treatment, an ABPI was performed to rule out arterial disease, which was normal. Hydrocolloid dressings have limited benefit for venous ulceration, while flucloxacillin is used to treat cellulitis. Diabetic foot ulcers are painless and tend to occur on pressure areas, while arterial ulcers have distinct characteristics and are associated with an abnormal ABPI.

Venous Ulceration and its Management

Venous ulceration is a type of ulcer that is commonly seen above the medial malleolus. To assess for poor arterial flow that could impair healing, an ankle-brachial pressure index (ABPI) is important in non-healing ulcers. A normal ABPI is usually between 0.9 – 1.2, while values below 0.9 indicate arterial disease. Interestingly, values above 1.3 may also indicate arterial disease, particularly in diabetics, due to false-negative results caused by arterial calcification.

The only treatment that has been shown to be of real benefit for venous ulceration is compression bandaging, usually four-layer. Oral pentoxifylline, a peripheral vasodilator, can also improve the healing rate. There is some small evidence supporting the use of flavonoids, but little evidence to suggest benefit from hydrocolloid dressings, topical growth factors, ultrasound therapy, and intermittent pneumatic compression. Proper management of venous ulceration is crucial to promote healing and prevent complications.

Understanding Pityriasis Versicolor

Pityriasis versicolor, also known as tinea versicolor, is a fungal infection that affects the skin’s surface. It is caused by Malassezia furfur, which was previously known as Pityrosporum ovale. This condition is characterized by patches that may be hypopigmented, pink, or brown, and it is most commonly found on the trunk. The patches may become more noticeable following a suntan, and scaling is a common symptom. Mild pruritus may also occur.

Pityriasis versicolor can affect healthy individuals, but it is more likely to occur in those who are immunosuppressed, malnourished, or have Cushing’s syndrome. Treatment typically involves the use of topical antifungal medications, with ketoconazole shampoo being the recommended option due to its cost-effectiveness for larger areas. If topical treatment fails, alternative diagnoses should be considered, and oral itraconazole may be prescribed. Scrapings may also be sent for confirmation of the diagnosis. Understanding the features, predisposing factors, and management of pityriasis versicolor can help individuals recognize and effectively treat this common fungal infection.

Management of Erythroderma in an Elderly Patient Living Alone

Erythroderma is a dermatological emergency that requires urgent treatment. In elderly patients who are frail and live alone, hospital admission is necessary. This is the case for an 86-year-old man with a history of psoriasis who presents with erythroderma. Topical emollients and steroids are key in management, but this patient requires intravenous fluids and close monitoring for infection and dehydration. Oral antibiotics are not indicated unless there are signs of infection. A topical steroid with a vitamin D analogue may be appropriate for psoriasis, but urgent assessment by Dermatology in an inpatient setting is necessary. An outpatient appointment is not appropriate for this patient due to his age and living situation.

Psoriasis and Psoriatic Arthropathy: Nail Changes

Psoriasis is a skin condition that can also affect the nails. The changes in the nails do not necessarily indicate the severity of psoriasis, but they are often associated with psoriatic arthropathy. In fact, around 80-90% of patients with psoriatic arthropathy have nail changes.

The nail changes that may occur in psoriasis include pitting, onycholysis (separation of the nail from the nail bed), subungual hyperkeratosis, and loss of the nail. These changes can affect both the fingers and toes. It is important to note that while nail changes may not be a reliable indicator of psoriasis severity, they can be a sign of psoriatic arthropathy, which is a type of arthritis that can occur in people with psoriasis.

The patient exhibits typical signs of a venous ulcer and appears to be in good overall health without any indications of infection. The recommended treatment for venous ulcers involves the use of compression dressings, but it is crucial to ensure that the patient’s arterial circulation is sufficient to tolerate some level of compression.

Venous Ulceration and its Management

Venous ulceration is a type of ulcer that is commonly seen above the medial malleolus. To assess for poor arterial flow that could impair healing, an ankle-brachial pressure index (ABPI) is important in non-healing ulcers. A normal ABPI is usually between 0.9 – 1.2, while values below 0.9 indicate arterial disease. Interestingly, values above 1.3 may also indicate arterial disease, particularly in diabetics, due to false-negative results caused by arterial calcification.

The only treatment that has been shown to be of real benefit for venous ulceration is compression bandaging, usually four-layer. Oral pentoxifylline, a peripheral vasodilator, can also improve the healing rate. There is some small evidence supporting the use of flavonoids, but little evidence to suggest benefit from hydrocolloid dressings, topical growth factors, ultrasound therapy, and intermittent pneumatic compression. Proper management of venous ulceration is crucial to promote healing and prevent complications.

The features described suggest acne rosacea, with episodic flushing, papules and pustules with telangiectasia on the nose, cheeks and forehead. Other conditions such as acne vulgaris, systemic lupus erythematosus, seborrhoeic dermatitis and shingles are unlikely based on the described symptoms.

Understanding Rosacea: Symptoms and Management

Rosacea, also known as acne rosacea, is a chronic skin condition that has no known cause. It typically affects the nose, cheeks, and forehead, and the first symptom is often flushing. Over time, telangiectasia (visible blood vessels) may appear, followed by persistent redness with papules and pustules. In some cases, rhinophyma (enlarged nose) may develop, and there may be ocular involvement, such as blepharitis. Sunlight can exacerbate symptoms.

Mild cases of rosacea may be treated with topical metronidazole, while topical brimonidine gel may be used for patients with predominant flushing but limited telangiectasia. More severe cases may require systemic antibiotics like oxytetracycline. Patients are advised to apply high-factor sunscreen daily and use camouflage creams to conceal redness. Laser therapy may be appropriate for those with prominent telangiectasia, and patients with rhinophyma should be referred to a dermatologist.

Overall, understanding the symptoms and management of rosacea can help individuals manage their condition and improve their quality of life.

Understanding Genital Herpes and Treatment Options

Genital herpes is a sexually transmitted infection caused by the herpes simplex viruses (HSV-1 or HSV-2). It presents as clusters of papules and vesicles on the outer genitals in both men and women, usually appearing 4-7 days after sexual exposure to HSV for the first time. Unfortunately, there is no cure for genital herpes, but treatment with aciclovir can reduce the duration of symptoms. Other treatment options include antibiotics like azithromycin and clindamycin for bacterial infections, antifungal agents like fluconazole for fungal infections, and metronidazole for anaerobic bacteria and protozoa. It is important to seek medical attention and start treatment as soon as possible to manage symptoms and prevent transmission to others.

Diagnostic Testing for Lichen Planus: Understanding Skin Patch Testing, Skin Prick Testing, and RAST

Lichen planus is a clinical diagnosis that can be made based on the characteristic appearance of the rash. However, in some cases, a biopsy may be helpful if the presentation is atypical. The diagnosis is typically made without the need for further testing, and treatment can be started promptly.

Skin patch testing and skin prick testing are not useful for diagnosing lichen planus, as they are mainly used for different types of hypersensitivity reactions. Skin patch testing is used for contact dermatitis and other type IV hypersensitivity reactions, while skin prick testing is used for type I hypersensitivity reactions, such as food allergies and pollen allergies.

Radioallergosorbent testing (RAST) is also unsuitable for diagnosing lichen planus, as it is used to determine the amount of immunoglobulin E (IgE) that reacts specifically with suspected or known allergens. RAST is useful for food allergies, inhaled allergens (such as pollen), and wasp/bee venom.

In summary, diagnostic testing is not typically required for lichen planus, as it can be diagnosed clinically. Skin patch testing, skin prick testing, and RAST are not useful for diagnosing lichen planus and are mainly used for different types of hypersensitivity reactions.

Topical corticosteroids can lead to patchy depigmentation in patients with darker skin, which is a potential adverse effect. These medications are commonly used to reduce inflammation in skin conditions like psoriasis and eczema. However, if used for an extended period or in high doses, they can cause local side effects such as skin thinning, excessive hair growth, and depigmentation. Therefore, the correct answer is depigmentation. Dry skin is not a typical side effect of topical steroid use, but it can occur with other topical preparations like benzoyl peroxide and topical retinoids. While systemic side effects like weight gain, hyperglycemia, hypertension, and mood changes are possible with corticosteroids, they are rare with topical use. Hyperglycemia is therefore an incorrect answer. Reduced hair growth at the application site is also incorrect, as corticosteroids can actually increase hair growth and may be used to treat alopecia.

Topical Steroids for Eczema Treatment

Eczema is a common skin condition that causes red, itchy, and inflamed skin. Topical steroids are often used to treat eczema, but it is important to use the weakest steroid cream that effectively controls the patient’s symptoms.

To determine the appropriate amount of topical steroid to use, the finger tip rule can be used. One finger tip unit (FTU) is equivalent to 0.5 g and is sufficient to treat an area of skin about twice the size of an adult hand.
The British National Formulary (BNF) recommends specific quantities of topical steroids to be prescribed for a single daily application for two weeks. These recommendations vary depending on the area of the body being treated. It is important to follow these guidelines to ensure safe and effective use of topical steroids for eczema treatment.

Rectal bleeding can have various causes, and it is crucial to differentiate between them as the treatments and prognosis can differ significantly. By utilizing signs and examinations, one can eliminate possibilities. If there are no masses, weight loss, or changes in bowel habits, rectal or colon cancer is less probable. Similarly, if there are no changes in bowel habits, abdominal pain, or weight loss, Crohn’s disease is less likely. This narrows down the possibilities to Louis-Bar syndrome and hereditary haemorrhagic telangiectasia. Louis-Bar syndrome, also known as ataxia telangiectasia, is a rare neurodegenerative disorder that typically manifests in early childhood with severe ataxia and other neurological symptoms.

Understanding Hereditary Haemorrhagic Telangiectasia

Hereditary haemorrhagic telangiectasia, also known as Osler-Weber-Rendu syndrome, is a genetic condition that is inherited in an autosomal dominant manner. It is characterized by the presence of multiple telangiectasia on the skin and mucous membranes. While 80% of cases have a family history, 20% occur spontaneously without prior family history.

There are four main diagnostic criteria for HHT. If a patient has two of these criteria, they are said to have a possible diagnosis of HHT. If they meet three or more of the criteria, they are said to have a definite diagnosis of HHT. These criteria include spontaneous, recurrent nosebleeds (epistaxis), multiple telangiectases at characteristic sites such as the lips, oral cavity, fingers, and nose, visceral lesions such as gastrointestinal telangiectasia (with or without bleeding), pulmonary arteriovenous malformations (AVM), hepatic AVM, cerebral AVM, and spinal AVM, and a first-degree relative with HHT.

In summary, HHT is a genetic condition that is characterized by multiple telangiectasia on the skin and mucous membranes. It can be diagnosed based on the presence of certain criteria, including nosebleeds, telangiectases, visceral lesions, and family history.

Palmoplantar pustulosis is often accompanied by psoriasis on other areas of the body and is strongly linked to smoking. Unlike pompholyx eczema, the connection to high temperatures and humidity is not as significant. Scabies, which is caused by the parasite Sarcoptes scabiei, results in severe itching of the hands and web spaces but is typically not a recurring issue. Symptoms include linear burrows and erythematous papules rather than vesicles.

Understanding Pompholyx Eczema

Pompholyx eczema, also known as dyshidrotic eczema, is a type of skin condition that affects both the hands and feet. It is often triggered by high temperatures and humidity, such as sweating. The main symptom of pompholyx eczema is the appearance of small blisters on the palms and soles, which can be intensely itchy and sometimes accompanied by a burning sensation. Once the blisters burst, the skin may become dry and crack.

To manage pompholyx eczema, cool compresses and emollients can be used to soothe the affected areas. Topical steroids may also be prescribed to reduce inflammation and itching. It is important to avoid further irritation by wearing gloves or protective footwear and avoiding exposure to irritants. With proper management, the symptoms of pompholyx eczema can be controlled and minimized.

The National Institute for Clinical Excellence updated its guideline for hypertension management in 2011, placing emphasis on the use of ambulatory blood pressure monitoring (ABPM) to confirm hypertension in individuals with elevated clinic readings. ABPM involves taking two measurements per hour during waking hours and using the average of at least 14 measurements to confirm a diagnosis of hypertension. Secondary causes of hypertension should be investigated in patients under 40 without traditional risk factors, those with other symptoms of secondary causes, and those with resistant hypertension. Hyperaldosteronism is the most common cause of secondary hypertension, and a trial of spironolactone may be used for both therapeutic and diagnostic purposes. Drug treatment for essential hypertension involves ACE inhibitors for those under 55 and calcium channel blockers for those over 55 or of black African or Caribbean origin. Step 2 involves using both ACE inhibitors and calcium channel blockers, while step 3 adds a thiazide-like diuretic. Further diuretics, beta-blockers, or alpha blockers may be considered in step 4, with expert advice sought.

NICE released updated guidelines in 2019 for the management of hypertension, building on previous guidelines from 2011. These guidelines aimed to classify hypertension into stages and recommend the use of ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM) to accurately diagnose hypertension. This is important because some patients experience white coat hypertension, where their blood pressure rises in a clinical setting, leading to potential overdiagnosis of hypertension. ABPM and HBPM allow for a more accurate assessment of a patient’s overall blood pressure and can prevent overdiagnosis.

NICE recommends measuring blood pressure in both arms when considering a diagnosis of hypertension and repeating measurements if there is a difference of more than 20 mmHg between arms. If the blood pressure is >= 140/90 mmHg, NICE suggests offering ABPM or HBPM to confirm the diagnosis. If the blood pressure is >= 180/120 mmHg, referral for specialist assessment is recommended if there are signs of retinal haemorrhage or papilloedema or life-threatening symptoms. If target organ damage is identified, antihypertensive drug treatment may be started immediately.

ABPM involves taking at least 2 measurements per hour during the person’s usual waking hours and using the average value of at least 14 measurements. If ABPM is not tolerated, HBPM should be offered. HBPM involves taking two consecutive measurements at least 1 minute apart, twice daily for at least 4 days, and using the average value of all remaining measurements.

Interpreting the results of ABPM/HBPM is important for determining treatment. If the average blood pressure is >= 135/85 mmHg (stage 1 hypertension), treatment may be considered for patients under 80 years of age with target organ damage, established cardiovascular disease, renal disease, diabetes, or a 10-year cardiovascular risk equivalent to 10% or greater. In 2019, NICE also recommended considering antihypertensive drug treatment for adults under 60 with stage 1 hypertension and an estimated 10-year risk below 10%. If the average blood pressure is >= 150/95 mmHg (stage 2 hypertension), drug treatment should be offered regardless of age.

Angular cheilitis can also be caused by a lack of vitamin B2 (riboflavin).

Understanding Zinc Deficiency and Acrodermatitis Enteropathica

Zinc deficiency is a condition that can lead to a range of symptoms, including acrodermatitis, which is characterized by red, crusted lesions that appear in an acral distribution, peri-orificial, perianal, and alopecia. Other symptoms of zinc deficiency include short stature, hypogonadism, hepatosplenomegaly, geophagia (ingesting clay/soil), cognitive impairment, and more.

One specific type of zinc deficiency is known as acrodermatitis enteropathica, which is a recessively inherited partial defect in intestinal zinc absorption. This condition can lead to a range of symptoms, including the characteristic skin lesions, as well as other physical and cognitive impairments. It is important to recognize the signs of zinc deficiency and seek appropriate treatment to prevent further complications. With proper management, individuals with zinc deficiency can lead healthy and fulfilling lives.

If treatment for acne is required during pregnancy, oral erythromycin is a suitable option, as the other medications are not recommended.

Acne vulgaris is a common skin condition that typically affects adolescents, with the face, neck, and upper trunk being the most commonly affected areas. It is characterized by the obstruction of hair follicles with keratin plugs, leading to the formation of comedones, inflammation, and pustules. The severity of acne can be classified as mild, moderate, or severe, depending on the presence and extent of inflammatory lesions, papules, and pustules.

The management of acne vulgaris typically involves a step-up approach, starting with single topical therapy such as topical retinoids or benzoyl peroxide. If this is not effective, topical combination therapy may be used, which includes a topical antibiotic, benzoyl peroxide, and topical retinoid. Oral antibiotics such as tetracyclines may also be prescribed, but they should be avoided in pregnant or breastfeeding women and children under 12 years of age. Erythromycin may be used in pregnancy, while minocycline is now considered less appropriate due to the possibility of irreversible pigmentation. Oral antibiotics should be used for a maximum of three months and always co-prescribed with a topical retinoid or benzoyl peroxide to reduce the risk of antibiotic resistance.

Combined oral contraceptives (COCP) are an alternative to oral antibiotics in women, and Dianette (co-cyrindiol) may be used as it has anti-androgen properties. However, it has an increased risk of venous thromboembolism compared to other COCPs, so it should generally be used second-line and for only three months. Oral isotretinoin is a potent medication that should only be used under specialist supervision, and it is contraindicated in pregnancy. Finally, there is no evidence to support dietary modification in the management of acne vulgaris.

The patient’s symptoms and medical history suggest a diagnosis of lichen planus, a skin condition with an unknown cause that is likely immune-mediated. The rash is typically itchy and appears as papules with a shiny, purplish color in areas such as the palms, soles, genitalia, and flexor surfaces of the arms. The rash often has a polygonal shape and may have white lines known as Wickham’s striae. Over time, the papules flatten and are replaced by hyperpigmentation. Oral involvement is common, with a white-lace pattern on the buccal mucosa. Management usually involves topical steroids, but more severe cases may require oral steroids or immunosuppressants. Atopic eczema, irritant eczema, molluscum contagiosum, and psoriasis are different skin conditions that do not fit the patient’s symptoms.