Dermatology Flashcards

Question

HPS is often triggered by?

Answer 1

upper airway infection or gastroenteritis.

Answer 2

most common in children under the age of 10 years.

Answer 3

Purpura (100%), Joint pain (75%), Abdominal pain (50%) Renal involvement (50%) - IgA nephritis

Answer 4

The rash is caused by inflammation and leaking of blood from small blood vessels under the skin, forming purpura. Purpura are red-purple lumps under the skin containing blood.

Answer 5

They are red-purple in colour and are palpable under the skin. Typically they start on the legs and spread to the buttocks. They can also affect the trunk and arms. In severe cases, skin ulceration and necrosis can develop. Purpura are seen in practically 100% of patients with HSP

Answer 6

arthralgia or arthritis mostly affecting the knees and ankles. The joints can become swollen and painful, with a reduced range of movement.

Answer 7

gastrointestinal haemorrhage, intussusception and bowel infarction.

Answer 8

HSP affects the kidneys in around 50% of patients, causing an IgA nephritis. This is sometimes referred to as **HSP nephritis.** This can lead to microscopic or macroscopic **haematuria** and **proteinuria**

Answer 9

**Full blood count** and **blood film** for thrombocytopenia, sepsis and leukaemia **Renal profile** for kidney involvement **Serum albumin** for nephrotic syndrome **CRP** for sepsis **Blood cultures** for sepsis **Urine dipstick** for proteinuria **Urine protein:creatinine ratio** to quantify the proteinuria **Blood pressure** for hypertension

Answer 10

There are many different sets of criteria for diagnosing HSP, the most recent being the EULAR/PRINTO/PRES criteria from 2010. This requires the patient to have palpable purpura (not petichiae) + at least one of: * Diffuse abdominal pain * Arthritis or arthralgia * IgA deposits on histology (biopsy) * Proteinuria or haematuria

Answer 11

The most important initial step is to exclude other serious pathology, such as **meningococcal septicaemia** and **leukaemia**. **Idiopathic thrombocytopenic purpura** and **haemolytic uraemic syndrome** are also differentials for a non-blanching rash

Answer 12

Management is supportive, with simple analgesia, rest and proper hydration.

Answer 13

Abdominal pain usually settles within a few days. Patients without kidney involvement can expect to fully recover within 4 to 6 weeks. A third of patients have a recurrence of the disease within 6 months. A very small proportion of patients will develop end stage renal failure.

Answer 14

Idiopathic thrombocytopenic purpura (ITP) is a condition characterised by idiopathic (spontaneous) thrombocytopenia (low platelet count) causing a purpuric rash (non-blanching rash).

Answer 15

ITP is caused by a **type II hypersensitivity reaction.** It is caused by the production of **antibodies** that target and destroy **platelets**. This can happen spontaneously, or it can be triggered by something, such as a viral infection.

Answer 16

diopathic thrombocytopenic purpura usually present in children under 10 years old. Often there is a history of a recent viral illness. The onset of symptoms occurs over 24 – 48 hours: * **Bleeding**, for example from the gums, epistaxis or menorrhagia * **Bruising** * **Petechial** or **purpuric rash**, caused by bleeding under the skin

Answer 17

The condition can be confirmed by doing an **urgent full blood count** for the **platelet count.** Other values on the FBC should be normal. Other causes of a low platelet count should be excluded, for example **heparin induced thrombocytopeni**a and **leukaemia**.

Answer 18

Treatment may be required if the patient is actively bleeding or severe thrombocytopenia (platelets below 10): * Prednisolone * IV immunoglobulins * Blood transfusions if required * Platelet transfusions only work temporarily * Platelet transfusions only work temporarily because the antibodies against platelets will begin destroying the transfused platelets as soon as they are infused.

Answer 19

* Avoid contact sports * Avoid intramuscular injections and procedures such as lumbar punctures * Avoid NSAIDs, aspirin and blood thinning medications * Advice on managing nosebleeds * Seek help after any injury that may cause internal bleeding, for example car accidents or head injuries

Answer 20

* Chronic ITP * Anaemia * Intracranial and subarachnoid haemorrhage * Gastrointestinal bleeding

Answer 21

Psoriasis is a chronic autoimmune condition that causes recurrent symptoms of psoriatic skin lesions.

Answer 22

There is a large variation in how severely patients are affected with psoriasis. There appears to be a genetic component but no clear genetic inheritance has been established. Around a third of patients have a first degree relative with psoriasis. The symptoms start in childhood in a third of patients.

Answer 23

Patches of psoriasis are **dry, flaky, scaly**, faintly **erythematous** skin lesions that appear in **raised** and **rough** plaques, commonly over the extensor surfaces of the **elbows** and **knees** and on the scalp

Answer 24

Plaque psoriasis Guttate psoriasis Pustular psoriasis Erythrodermic psoriasis

Answer 25

Pustular psoriasis Erythrodermic psoriasis

Answer 26

Plaque psoriasis

Answer 27

Guttate psoriasis

Answer 28

n children the distribution and presentation of psoriasis may differ from adults. Guttate psoriasis is more common in children, often triggered by a throat infection. Plaques of psoriasis are likely to be smaller, softer and less prominent. There are a few specific signs suggestive of psoriasis: * **Auspitz sign** refers to small points of bleeding when plaques are scraped off * **Koebner phenomenon** refers to the development of psoriatic lesions to areas of skin affected by trauma * **Residual pigmentation** of the skin after the lesions resolve

Answer 29

The treatment options include: * Topical steroids * Topical vitamin D analogues (calcipotriol) * Topical dithranol * Topical calcineurin inhibitors (tacrolimus) are usually only used in adults * Phototherapy with narrow band ultraviolet B light is particularly useful in extensive guttate psoriasis

Answer 30

* Dovobet * Enstilar

Answer 31

Nail psoriasis Psoriatic arthritis depression and anxiety obesity hyperlipidaemia hypertension type 2 diabetes.

Answer 32

Erythema nodosum is a condition where red lumps appear across the patient’s shins. Erythema means red and nodosum directly translates from Latin as “knots”, referring to lumps.

Answer 33

It is caused by inflammation of the subcutaneous fat on the shins. Inflammation of fat is called panniculitis. It is caused by a hypersensitivity reaction. In around half of patients there is no identifiable cause. It is associated with a number of triggers and underlying conditions.

Answer 34

Erythema nodosum is caused by a hypersensitivity reaction, and there is often an identifiable cause: * Streptococcal throat infections * Gastroenteritis * Mycoplasma pneumoniae * Tuberculosis * Pregnancy * Medications, such as the oral contraceptive pill and NSAIDs It is also associated with chronic diseases: * Inflammatory bowel disease * Sarcoidosis * Lymphoma * Leukaemia

Answer 35

Erythema nodosum often indicates **inflammatory bowel disease** or **sarcoidosis** in exams.

Answer 36

Erythema nodosum presents with **red, inflamed, subcutaneous nodules** across both shins. The nodules are **raised** and can be **painful and tender**. Over time the nodules settle and appears as bruises. When you suspect someone has erythema nodosum it is important to look for signs and symptoms of potential triggers and underlying medical conditions.

Answer 37

The diagnosis of erythema nodosum is based on the clinical presentation. Investigations can be helpful in assessing the underlying cause: * **Inflammatory markers** (CRP and ESR) * **Throat swab** for streptococcal infection * **Chest xray** can help identify mycoplasma, tuberculosis, sarcoidosis and lymphoma * **Stool microscopy and culture** for campylobacter and salmonella * **Faecal calprotectin** for inflammatory bowel disease

Answer 38

Management mainly involves investigating for an underlying condition and treating the underlying cause. Erythema nodosum is managed conservatively with rest and analgesia. Steroids may be used to help settle the inflammation.

Answer 39

Most cases of eythema nodosum will fully resolve within **6 weeks**, however it can last longer.

Answer 40

Acne vulgaris (acne) is an extremely common condition, often affecting people during puberty and adolescence. Most people are affected at some point during their lives, and symptoms can range from mild to severe.

Answer 41

Acne is caused by **chronic inflammation**, with or without **localised infection**, in pockets within the skin known as the **pilosebaceous unit**. The pilosebaceous units are the tiny dimples in the skin that contain the **hair follicles** and **sebaceous glands**. The sebaceous glands produce the natural skin oils and a waxy substance known as **sebum.** Acne results from increased production of **sebum**, trapping of **keratin** (dead skin cells) and blockage of the **pilosebaceous unit**. This leads to **swelling** and **inflammation** in the **pilosebaceous uni**t. **Androgenic hormones** increase the production of sebum, which is why acne is exacerbated by puberty and improves with anti-androgenic hormonal contraception. Swollen and inflamed units are called **comedones.**

Answer 42

Propionibacterium acnes bacteria colonises the skin. It is thought that excessive growth of this bacteria can exacerbate acne. Many of the treatments of acne aim to reduce these bacteria.

Answer 43

There is significant variation in the severity of acne. It presents with red, inflamed and sore “spots” on the skin, typically distributed across the face, upper chest and upper back.

Answer 44

Treatment is initiated in a stepwise fashion based on the severity and response to treatment: * No treatment may be acceptable if mild * **Topical benzoyl peroxide** reduces inflammation, helps unblock the skin and is toxic to the **P. acnes** bacteria * **Topical retinoids** (chemicals related to vitamin A) slow the production of **sebum** (women of childbearing age need effective contraception) * **Topical antibiotics** such as **clindamycin** (prescribed with benzoyl peroxide to reduce bacterial resistance) * **Oral antibiotics** such as **lymecycline** * **Oral contraceptive pill** can help female patients stabilise their hormones and slow the production of **sebum**

Answer 45

Oral retinoids for severe acne (i.e. isotretinoin) is an effective last-line option, although it is only prescribed by a specialist after other methods fail. This needs careful follow-up and monitoring and reliable contraception in females. Retinoids are highly teratogenic.

Answer 46

Co-cyprindiol (Dianette) is the most effective combined contraceptive pill for acne due to it’s anti-androgen effects. It has a higher risk of **thromboembolism**, so treatment is usually discontinued once acne is controlled and it is not prescribed long term.

Answer 47

* Dry skin and lips * Photosensitivity of the skin to sunlight * Depression, anxiety, aggression and suicidal ideation. Patients should be screened for mental health issues prior to starting treatment. * Rarely Stevens-Johnson syndrome and toxic epidermal necrolysis

Answer 48

rodent ulcers

Answer 49

basal cell carcinoma

Answer 50

Malignant tumour of **epidermal keratinocytes** Normally affects **middle aged-older** individuals

Answer 51

Risk factors include pale skin type, UV sun exposure, immunosuppression, previous skin cancer, inherited syndromes

Answer 52

Common sites include face, arms, legs (sun exposed areas)

Answer 53

Nodular Superficial Sclerosing Pigmented

Answer 54

Nodular BCC

Answer 55

Superficial

Answer 56

Sclerosing

Answer 57

**• Surgical excision** is usual treatment of choice - allows histological examination of the tumour and margins **• Radiotherapy** when surgery is inappropriate **• Topical treatment** (imiquimod cream) or photodynamic therapy for superficial subtype **• Prognosis** is excellent especially for smaller lesions - locally invasive if untreated but metastatic spread is extremely rare **• High risk of developing further lesions** (~50% ppl develop further lesion within 5 years) and affected individuals at ^ risk of developing other forms of skin cancer

Answer 58

Squamous Cell Carinoma

Answer 59

Risk factors include UV sun exposure, (HPV infection in Black people), immunosuppression and smoking (particularly SCC of lips)

Answer 60

Most SCCs are found on sun-exposed sites, particularly the face, lips, ears, hands, forearms, lower legs & anogenital region in Black people

Answer 61

* Surgical excision - treatment of choice * Radiotherapy - for large, non-resectable tumours * Early stage tumours \>90% 5 year survival * Approximately 10% rate of metastasis overall

Answer 62

**Cutaneous horn** – excessive keratin production results in a hard horn; this can overlie SCC, pre-cancerous lesions or warts

Answer 63

**Keratoacanthoma** – a rapidly growing keratinising skin nodule which can look identical to SCC but resolves without treatment.

Answer 64

solar keartosis

Answer 65

Develop in areas of sun damage (face, backs of hands, bald scalps), usually older individuals. Rarely seen in Black people

Answer 66

FALSE Premalignant - small minority (\<1%) may eventually progress to SCC

Answer 67

• Treatment options include cryotherapy and curettage for individual lesions or topical 5-fluorouracil for field treatment

Answer 68

SCC in situ

Answer 69

Commonly found on the lower leg or trunk, more often in women.

Answer 70

Bowen’s disease may resemble discoid eczema, psoriasis or superficial basal cell carcinoma.

Answer 71

Treated by cryotherapy, curettage, topical 5- fluorouracil or imiquimod, or photodynamic therapy.

Answer 72

rodent ulcers

Answer 73

An invasive malignant tumour of the epidermal melanocytes, which has the potential to metastasise

Answer 74

* Increasing age * UV exposure * Previous invasive melanoma or melanoma in situ * Previous non-melanoma skin cancer * Many melanocytic naevi (moles) especially if atypical naevi * Strong family history of melanoma with 2 or more first-degree relatives affected * Fair skin that burns easily

Answer 75

Superficial Spreading Mucosal and Ocular Melanomas Lentigo Maligna Melanoma Nodular Melanoma

Answer 76

Lentigo Maligna Melanoma

Answer 77

Superficial Spreading

Answer 78

Mucosal and Ocular Melanomas

Answer 79

Nodular Melanoma

Answer 80

Surgical excision - definitive treatment •Sentinel lymph node biopsy for higher risk lesions •Surgery if nodal disease •Radiotherapy – only for metastatic disease •Targeted or immunotherapy if systemic metastases

Answer 81

Recurrence of melanoma based on **Breslow** thickness (thickness of tumour): * \<0.76mm thick – low risk, * 0.76mm-1.5mm thick – medium risk, * \>1.5mm thick – high risk

Answer 82

* 5 year survival rates based on the TNM classification: * Stage 1 (T \<2mm thick, N0, M0) – 90%, * Stage 2 (T\>2mm thick, N0, M0) – 80% * Stage 3 (N≥1, M0) – 40-50% * Stage 4 (M ≥ 1) – 20-30%

Answer 83

Erythema multiforme is an erythematous rash caused by a hypersensitivity reaction. The most common causes are **viral infections** and **medications**. It is also notably associated with the **herpes simplex virus** (causing coldsores) and **mycoplasma pneumonia.**

Answer 84

Erythema multiforme produces a widespread, itchy, erythematous rash. It produces characteristic “target lesions”. **Target lesions** are red rings within larger red rings, with the darkest red at the centre, similar to a bulls-eye target. It does not usually affect the mucous membranes but can cause a sore mouth (**stomatitis**). The symptoms come on abruptly over a few days. It may be associated with other symptoms of mild fever, **stomatitis**, muscle and joint aches, headaches and general flu-like symptoms

Answer 85

The diagnosis is made clinically based on the appearance of the rash. It is important to identify the underlying cause. Where there is a clear underlying cause, for example a **recent coldsore or treatment with penicillin**, it may be managed **supportively.** Where there is no clear underlying cause it may be worth investigating further, for example doing a **chest xray to look for mycoplasma pneumonia.** Most of the time erythema multiforme is **mild and resolves spontaneously** within 1 to 4 weeks without any treatment or lasting effects. Cases may be recurrent, particularly associated with recurrent coldsores. **Severe** cases may require **admission to hospital,** particularly where it affects the oral mucosa. Treatments used in severe cases includ**e IV fluids, analgesia and steroids (systemic or topical).** The use of systemic steroids is controversial. Antibiotics or antivirals may be used where infection is present.

Answer 86

Urticaria are also known as hives. They are small itchy lumps that appear on the skin. This can be localised to a specific area or widespread. They may be associated with a **patchy erythematous rash.** They may be associated with **angioedema** and **flushing of the skin**. Urticaria can be classified as **acute urticaria or chronic urticaria.**

Answer 87

Urticaria are caused the release of **histamine** and other pro-inflammatory chemicals by **mast cells** in the skin. This may be part of an **allergic reaction** in **acute urticaria** or an autoimmune reaction in **chronic idiopathic urticaria.**

Answer 88

Acute urticaria is typically triggered by something that stimulates the mast cells to release histamine. This may be: * Allergies to food, medications or animals * Contact with chemicals, latex or stinging nettles * Medications * Viral infections * Insect bites * Dermatographism (rubbing of the skin)

Answer 89

Chronic idiopathic urticaria Chronic inducible urticaria Autoimmune urticaria

Answer 90

**Chronic idiopathic urticaria** describes recurrent episodes of chronic urticaria without a clear underlying cause or trigger. **Chronic inducible urticaria** describes episodes of chronic urticaria that can be induced by certain triggers, such as: * Sunlight * Temperature change * Exercise * Strong emotions * Hot or cold weather * Pressure (dermatographism) **Autoimmune urticaria** describes chronic urticaria associated with an underlying autoimmune condition, such as systemic lupus erythematosus.

Answer 91

**Antihistamines** are the main treatment for urticaria. **Fexofenadine** is usually the antihistamine of choice for chronic urticaria. **Oral steroids** may be considered as a short course for severe flares. In very problematic cases referral to a specialist may be required to consider treatment with: * **Anti-leukotrienes** such as **montelukast** * **Omalizumab**, which targets IgE * **Cyclosporin**

Answer 92

Chickenpox is caused by the **varicella zoster virus (VZV).** It causes a **highly contagious,** generalised **vesicular** rash. It is common in children. Once a child has had an episode of chickenpox, they develop immunity to the VZV virus and will not be affected again.

Answer 93

Chickenpox is characterised by widespread, erythematous, raised, vesicular (fluid filled), blistering lesions. The rash usually starts on the trunk or face and spreads outwards affecting the whole body over 2 – 5 days. Eventually the lesions scab over, at which point they stop being contagious. * Other symptoms: * Fever is often the first symptom * Itch * General fatigue and malaise *

Answer 94

Chickenpox is highly contagious and spread through direct contact with the lesions or through infected droplets from a cough or sneeze. Patients become symptomatic **10** days to **3** weeks after exposure. The stop being contagious after all the **lesions have crusted over.**

Answer 95

* Bacterial superinfection * Dehydration * Conjunctival lesions * Pneumonia * Encephalitis (presenting as ataxia .

Answer 96

After the infection the virus can lie dormant in the **sensory dorsal root ganglion** cells and cranial nerves reactivate later in life as **shingles** or **Ramsay Hunt syndrom**e

Answer 97

Pregnant women that are known to be immune to chickenpox are not at risk when in contact with chickenpox. When they are not immune, **varicella zoster immunoglobulins** can be given to protect them against the virus after exposure. Chickenpox in pregnancy, before 28 weeks gestation, can cause developmental problems in the fetus in a small portion of patients. This is known as **congenital varicella syndrome**. Chickenpox in the mother around the time of delivery can lead to life threatening neonatal infection and is treated with **varicella zoster immunoglobulins** and **aciclovir.**

Answer 98

Chickenpox is usually a mild self limiting condition that does not require treatment in otherwise healthy children. **Aciclovir** may be considered in **immunocompromised patients,** adults and adolescents over 14 years presenting within 24 hours, neonates or those at risk of complications. **Complications** such as **encephalitis** require admission for inpatient management. Symptoms of itching can be treated with **calamine lotion and chlorphenamine** (antihistamine). Patients should be kept off school and avoid pregnant women and immunocompromised patients until all the lesions are dry and crusted over. This is usually around 5 days after the rash appears.

Answer 99

Hand, foot and mouth disease is caused by the **coxsackie A** virus. Incubation is usually **3 – 5** days.

Answer 100

The illness starts with typical viral upper respiratory tract symptoms such as tiredness, sore throat, dry cough and raised temperature. After 1 – 2 days small mouth ulcers appear, followed by blistering red spots across the body. As the name suggests, these spots are most notable on the hands, feet and around the mouth. Painful mouth ulcers, particularly on the tongue are also a key feature. The rash may be itchy.

Answer 101

Diagnosis is made based on the clinical appearance of the rash. There is no treatment for hand, foot and mouth disease. Management is supportive, with adequate fluid intake and simple analgesia such as paracetamol if required. The rash and illness resolve spontaneously without treatment after a week to 10 days It is highly contagious and advice should be give about measures to avoid transmission, such as avoiding sharing towels and bedding, washing hands and careful handling of dirty nappies.

Answer 102

Rarely it can cause complications: * Dehydration * Bacterial superinfection * Encephalitis

Answer 103

Molluscum contagiosum is a viral skin infection caused by the **molluscum contagiosum** virus, which is a type of **poxvirus.**

Answer 104

Molluscum contagiosum is characterised by small, flesh coloured **papules** (raised individual bumps on the skin) that characteristically have a **central dimple.** They typically appear in **“crops”** of multiple lesions in a local area. It is spread through direct contact or by sharing items like towels or bedsheets. The papules resolve by themselves without any treatment, however this can take up to 18 months. Once they resolve the skin returns to normal. Scratching or picking the lesions should be avoided as it can lead to spreading, scarring and infection.

Answer 105

**No treatment or change in lifestyle is required and children** can continue all their normal activities. They should **avoid sharing towels or other close contac**t with the lesions to minimise the risk of spreading the infection. Usually just simple reassurance and education is enough. Rarely, if bacterial superinfection infection occurs in the lesions as a result of scratching, this may require treatment **with antibiotics.** Options include topical **fuscidic acid or oral flucloxacillin.** Immunocompromised patients and those with very extensive lesions or lesions in problematic areas such as the eyelid or anogenital area may require referral to a specialist. Specialist treatment options include: Topical potassium hydroxide, benzoyl peroxide, podophyllotoxin, imiquimod or tretinoin Surgical removal and **cryotherap**y (freezing with liquid nitrogen) is an option but can lead to scarring

Answer 106

Pityriasis rosea a generalised, self limiting rash that has an unknown cause. It often occurs in adolescents and young adults. It may be caused by a virus such as human herpes virus (HHV-6 or HHV-7), but no definitive causative organism had been established.

Answer 107

There may be prodromal symptoms prior to the rash developing. These include headache, tiredness, loss of appetite and flu-like symptoms. The rash starts with a characteristic **herald patch**. This is a **faint red or pink, scaly, oval** shaped lesion that is **2cm** or more in diameter, usually occurring somewhere on the torso. It appears 2 or more days prior to the rest of the rash. If you suspect pityriasis, ask and look for a herald patch. Most, but not all, patients have a herald patch. The rash consists of widespread **faint red or pink, slightly scaly, oval shaped lesions,** usually less than 2 cm in diameter. On the torso they can be arranged in a characteristic **“christmas tree”** fashion, following the lines of the ribs. In dark skinned patients the lesions can be grey coloured, lighter or darker than their skin colour. Other symptoms may be present: * Generalised itch * Low grade pyrexia * Headache * Lethargy

Answer 108

The rash resolves without treatment within 3 months. It can leave a discolouration of the skin where the lesions were, however these will also resolved within another few months.

Answer 109

There is no treatment for the rash. It will resolve spontaneously without any long term effects. Patient education and reassurance is all that is required. It is not contagious and they can continue all their normal activities. They may require symptomatic treatment if bothered by itching. This may include **emollients, topical steroids or sedating antihistamines** at night to help with sleep (e.g. chlorphenamine).

Answer 110

Seborrhoeic dermatitis is an inflammatory skin condition that affects the sebaceous glands. The sebaceous glands are the oil producing glands in the skin. It affects areas that have a lot of these glands, such as the **scalp, nasolabial folds and eyebrows.** It causes erythema, dermatitis and crusted dry skin. In infants it causes a crusted dry flaky scalp, often called **cradle cap.** It is thought that **Malassezia yeast** colonisation has a role to play in the development of seborrhoeic dermatitis, and the condition improves with anti-fungal treatment

Answer 111

Infantile seborrhoeic dermatitis (cradle cap) causes a crusted **flaky scalp.** It is a self limiting condition and **usually resolves by 4 months of age**, but **can last until 12 months**. **First line treatment** is by applying **baby oil, vegetable oil or olive oil, gently brushing the scalp then washing off**. When this is not effective, w**hite petroleum jelly** can be used overnight to soften the crusted areas before washing off in the morning. The next step is a **topical anti-fungal** cream such as **clotrimazole or miconazole,** used for up to **4 weeks.** Severe or unresponsive cases may need referral to a dermatologist.

Answer 112

Mild seborrhoeic dermatitis of the scalp presents with flaky itchy skin on the scalp (dandruff). More severe cases cause more dense oily scaly brown crusting. This commonly occurs in adolescents and adults rather than children. First line treatment is with **ketoconazole shampoo,** left on for 5 minutes before washing off. Topical steroids may be used if there is severe itching. It often reoccurs after successful treatment.

Answer 113

Seborrhoeic dermatitis of the face and body presents with **red, flaky, crusted, itchy skin.** It commonly affects the **eyelids, nasolabial folds, ears, upper chest and back.** **First line treatment** is with an anti fungal cream, such as **clotrimazole or miconazole**, used for up to 4 weeks. Localised inflamed areas may benefit from a topical steroids, such as **hydrocortisone 1%.** Severe or unresponsive cases should be referred to a dermatologist or paediatrician.

Answer 114

Ringworm is a fungal infection of the skin. It is also known as tinea and dermatophytosis. Fungal infections have specific names depending on the area they affect:

Answer 115

**Tinea capitis** refers to ringworm affecting the **scalp (**caput meaning head) **Tinea pedis** refers to ringworm affecting the **feet,** also known as athletes foot (pedis meaning foot) **Tinea cruris** refers to ringworm of the **groin** (cruris meaning leg) **Tinea corporis** refers to ringworm on the **body** (corporis meaning body) **Onychomycosis** refers to a fungal **nail infection**

Answer 116

The most common type of fungus that causes ringworm is called **trichophyton.** It is spread through contact with infected individuals, animals or soil.

Answer 117

Ringworm presents as an **itchy rash that is erythematous, scaly and well demarcated.** There is often one or several rings or circular shaped areas that spread outwards, with a well demarcated edge. The edge is more prominent and red and the area in the centre is more faint in colour.

Answer 118

**Tinea capitis** can present with well demarcated hair loss. There will also be itching, dryness and erythema of the scalp. This is more common in children than adults.

Answer 119

Tinea pedis (athletes foot) presents with white or red, flaky, cracked, itchy patches between the toes. The skin may split and bleed. This is often the result of sharing changing rooms with someone that has athletes foot and is more likely to occur when feet are sweaty and damp for prolonged periods.

Answer 120

(fungal nail infections) presents with thickened, discoloured and deformed nails.

Answer 121

Treatment of ringworm is with anti-fungal medications: * Anti-fungal creams such as **clotrimazole** and **miconazole** * Anti-fungal shampoo such as **ketoconazole** for **tinea capitis** * Oral anti-fungal medications such as **fluconazole, griseofulvin and itraconazole** Fungal nail infections can be treated with **amorolfine nail lacquer for 6 – 12 months.** Resistant cases may need oral terbinafine, however the patient will need their LFTs monitoring before and whilst taking this. A mild topical steroid can help settle the inflammation and itching. A common combination is miconazole 2% and hydrocortisone 1% cream **(Daktacort).**

Answer 122

* Wear loose breathable clothing * Keep the affected area clean and dry * Avoid sharing towels, clothes and bedding * Use a separate towel for the feet with tinea pedis * Avoid scratching and spreading to other areas * Wear clean dry socks every day

Answer 123

Tinea incognito refers to a more extensive and less well recognised fungal skin infection that results from the use of steroids to treat an initial fungal infection. ## Footnote This often occurs when the initial presentation of ringworm was misdiagnosed as **dermatitis and a topical steroid** was prescribed. The steroid improves the itching and inflammation but accelerates the growth of the fungal infection by dampening the immune response in the local area. When the steroid is stopped the itchy rash caused by the fungus returns and is much worse than previously. It may be less recognisable as ringworm due to a less well-demarcated border and fewer scales, giving rise to the incognito name.

Answer 124

Scabies are tiny mites called Sarcoptes scabiei that burrow under the skin causing infection and intense itching. They lay eggs in the skin, leading to further infection and symptoms. It can take up to **8 weeks** for any symptoms or rash to appear after the initial infestation.

Answer 125

Scabies presents with incredibly itchy small red spots, possibly with **track marks** where the mites have **burrowed**. The classic location of the rash is between the **finger webs**, but it can spread to the whole body. **TOM TIP:** Scabies is more common than you may think. When someone presents with an itchy rash, ask whether anyone they live with has a similar rash and check between their finger webs for little red dots and track marks that may indicate scabies.

Answer 126

Treatment is with **permethrin cream**. **left on for 8 – 12 hours and then washed off.** This should be r**epeated a week later to kill all the eggs** that survived the first treatment and have now hatched. **Oral ivermectin** as a single dose that can be repeated a week later is an option for difficult to treat or crusted scabies. Scabies is contagious to all household and close contacts. When one person is diagnosed, all household and close contacts should also be treated in exactly the same way, even if asymptomatic. This is because they may be infected and not yet have symptoms. **All clothes, bedclothes, towels and other materials in contact with scabies need to be washed on a hot wash to destroy the mites**. Thorough hoovering of carpets and furniture is also essential. **Itching can continue for up to 4 weeks** after successful treatment. **Crotamiton cream and chlorphenamine** at night at night can help with the itching.

Answer 127

**Crusted scabies** is also known as **Norwegian scabies.** It is a serious infestation with scabies in patients that are **immunocompromised.** These patient may have over a million mites in their skin. They are extremely contagious. Rather than individual spots and burrows, they have patches of red skin that turn into scaly plaques. These can be misdiagnosed as psoriasis. Immunocompromised patients may not have an itch as they do not mount an immune response to the infestation. They may need admission for treatment as an inpatient with oral **ivermectin** and isolation.

Answer 128

Impetigo is a superficial bacterial skin infection, usually caused by the **staphylococcus aureus bacteria.** A “golden crust” is characteristic of a staphylococcus skin infection. It is also less commonly caused by the **streptococcus pyogenes** bacteria. Impetigo is contagious and children should be kept off school during the infection. Impetigo occurs when bacteria enter via a break in the skin. This may be in otherwise healthy skin or may be related to eczema or dermatitis.

Answer 129

mpetigo can be classified as **non-bullous** or **bullous.**

Answer 130

Non-bullous impetigo typically occurs around the nose or mouth. The **exudate** from the lesions dries to form a **“golden crust”.** They are often unsightly but do not usually cause systemic symptoms or make the person unwell. **Topical fusidic acid** can be used to treat localised non-bullous impetigo. Draft NICE guidelines from August 2019 suggest using **antiseptic cream (hydrogen peroxide 1% cream)** first line rather than antibiotics for localised non-bullous impetigo. **Oral flucloxacillin** is used to treat more wide spread or severe impetigo. Flucloxacillin is the antibiotic of choice for staphylococcal infections. Advise about measure to avoid spreading the impetigo. Patients should be given advice about not touching or scratching the lesions, hand hygiene and avoiding sharing face towels and cutlery. They need to be off school until all the lesions have healed or they have been treated with antibiotics for at least 48 hours.

Answer 131

Bullous impetigo is always caused by the **staphylococcus aureus bacteria**. These bacteria can produce epidermolytic toxins that break down the proteins that hold skin cells together. This causes 1 – 2 cm fluid filled vesicles to form on the skin. These vesicles grow in size and then burst, forming a **“golden crust”.** Eventually they heal without scarring. These lesions can be painful and itchy.

Answer 132

reatment of bullous impetigo is with antibiotics, usually **flucloxacillin.** This may be given orally or intravenously if they are very unwell or at risk of complications. The condition is very contagious and patients should be isolated where possible.

Answer 133

Impetigo usually responds well to treatment without any long term adverse effects. Rarely there can be complications: * Cellulitis if the infection gets deeper in the skin * Sepsis * Scarring * Post streptococcal glomerulonephritis * Staphylococcus scalded skin syndrome * Scarlet fever

Answer 134

Candida in the nappy area (thrush) is a common finding. Signs that would point to a candidal infection rather than simple nappy rash are: * Rash extending into the skin folds * Larger red macules * Well demarcated scaly border * Circular pattern to the rash spreading outwards, similar to ringworm * Satellite lesions, which are small similar patches of rash or pustules near the main rash Check for **oral thrush with a white coating on the tongue,** as this is likely to indicate a fungal infection in the nappy area.

Answer 135

Simple measures can be taken to improve skin health and treat nappy rash within a few days: * Switching to highly absorbent nappies (disposable gel matrix nappies) * Change the nappy and clean the skin as soon as possible after wetting or soiling * Use water or gentle alcohol free products for cleaning the nappy area * Ensure the nappy area is dry before replacing the nappy * Maximise time not wearing a nappy Infection with candida or bacteria warrants treatment with an anti-fungal cream (clotrimazole or miconazole) or antibiotic (fusidic acid cream or oral flucloxacillin).

Answer 136

Candida infection Cellulitis Jacquet’s erosive diaper dermatitis Perianal pseudoverrucous papules and nodules

Answer 137

Non-blanching rashes are caused by bleeding under the skin. Petechiae are small (\< 3mm), non blanching, red spots on the skin caused by burst capillaries. Purpura are larger (3 – 10mm) non-blanching, red-purple, macules or papules created by leaking of blood from vessels under the skin.

Answer 138

Any child presenting with a non-blanching rash needs immediate investigation for the underlying cause. The most concerning differential is **meningococcal septicaemia**. Patients with features of sepsis need immediate management for life threatening **meningococcal sepsis.**

Answer 139

**Meningococcal septicaemia or other bacterial sepsis**: This presents with a feverish unwell child. Any features of meningococcal septicaemia indicate emergency management with immediate antibiotics. This can lead to significant morbidity and mortality if treatment is delayed. **Henoch-Schonlein purpura (HSP)**: This typically presents as a purpuric rash on the legs and buttocks and may have associated abdominal or joint pain. **Idiopathic thrombocytopenic purpura (ITP):** This develops over several days in an otherwise well child. **Acute leukaemias:** This presents with a gradual development of petechiae, potentially with other signs such as anaemia, lymphadenopathy and hepatosplenomegaly. **Haemolytic uraemic syndrome (HUS):** This is associated with oliguria (very low urine output) and signs of anaemia. This often presents in a child with recent diarrhoea. **Mechanical**: Strong coughing, vomiting or breath holding can produce petechiae in a “superior vena cava distribution”, above the neck and most prominently around the eyes. **Traumatic:** Tight pressure on the skin, for example in non-accidental injury, or occlusion of blood in an area of skin can lead to traumatic petechiae. **Viral illness:** This is often the explanation when other causes and serious illness are excluded. Typical causes are influenza and enterovirus.

Answer 140

* **Full blood count:** Anaemia can suggest HUS or leukaemia. Low white cells can suggest neutropenic sepsis or leukaemia. Low platelets can suggest ITP or HUS. * **Urea and electrolytes:** High urea and creatinine can indicate HUS or HSP with renal involvement. * **C-reactive protein (CRP):** This is a non-specific indication of inflammation or infection and can be useful but not definitive in excluding sepsis. * **Erythrocyte sedimentation rate (ESR)**: This is a non-specific indication of inflammatory illness such as a vasculitis (HSP) or infection. * **Coagulation screen**, including PT, APTT, INR and fibrinogen can diagnose clotting abnormalities. * **Blood culture:** This can be useful but not definitive in diagnosing or excluding sepsis. * **Meningococcal PCR:** This can confirm meningococcal disease, although this should not delay treatment. * **Lumbar puncture**: To diagnose meningitis or encephalitis. * **Blood pressure:** Hypertension can occur in HSP and HUS. Hypotension can occur in septic shock. * **Urine dipstick:** Proteinuria and haematuria can suggest HSP with renal involvement, or HUS.

Answer 141

Medications * Anti-epileptics * Antibiotics * Allopurinol * NSAIDs Infections * Herpes simplex * Mycoplasma pneumonia * Cytomegalovirus * HIV

Answer 142

The condition has a spectrum of severity. Some cases are mild whilst others are very severe and can potentially be fatal. Patients usually start with non-specific symptoms of fever, cough, sore throat, sore mouth, sore eyes and itchy skin. They then develop a purple or red rash that spreads across the skin and starts to blister. A few days after the blistering starts, the skin starts to break away and shed leaving the raw tissue underneath. Pain, erythema, blistering and shedding can also happen to the lips and mucous membranes. Eyes can become inflamed and ulcerated. It can also affect the urinary tract, lungs and internal organs.

Answer 143

SJS and TEN are medical emergencies and patients should be admitted to a suitable dermatology or burns unit for treatment. Good supportive care is essential, including nutritional care, antiseptics, analgesia and ophthalmology input. Treatment options include steroids, immunoglobulins and immunosuppressant medications guided by a specialist.

Answer 144

* **Secondary infection:** The breaks in the skin can lead to secondary bacterial infection, cellulitis and sepsis. * **Permanent skin damage:** Skin involvement can lead to scarring and damage to skin, hair, nails, lungs and genitals. * **Visual complications:** Depending on the severity, eye involvement can range from sore eyes to severe scarring and blindness.