Miscellaneous Skin Conditions

Question 1

What is lichen planus?

Answer 1

Lesions on the palmer aspects of wrists, forearms, ankles and legs also on genitalia.

Can be a drug eruption due to gold, quinine and thiazides

Question 2

Describe the lesions seen on a patient with lichen planus?

Answer 2

Purple, pruritic, plantar (flat topped) papules that are often polygonal and have white line patterns on the surface – Wicham’s striae
Oral involvement in around 50% of patients typically white lace pattern on buccal mucosa
Scaring alopecia and longitudinal ridges on nails and thinning of nails
Often arises on sites of trauma – Koebner phenomenon

Question 3

How long does lichen planus last?

Answer 3

Lasts 6-18 months and thought to be immune mediated

Question 4

How is lichen planus managed?

Answer 4

Topical steroids and benzydamine mouthwash for oral involvement
If Extensive may require oral steroids or immunosuppression

Question 5

What can cause non-scarring alopecia and how should it be treated?

Answer 5

Alopecia areata – smooth well-defined round patches of loss of hair. Usually regrows after 3 months. Alopecia totalis – all the head, Alopecia universalis – all the body.
Telogen effluvium – shedding of hair after a period of stress e.g. childbirth, surgery of severe illness.
Nutritional – loss of iron or zinc

Consider topical steroids and psychological support also minoxidil

Question 6

What can cause scarring alopecia?

Answer 6

Inflammatory damage that damages or destroys the hair follicle stem cells such as lichen planus and discoid lupus. Can also be from trauma or tumour.

Question 7

What skin infections are common markers of HIV infection?

Answer 7

Herpes – simplex and zoster may both reoccur and be particularly troublesome
Epstein Barr virus – oral hairy leukoplakia
Warts – widespread oral mucosa, face perianal region and gential tract
Molluscum contagiosum – widespread and in atypical sites – treat with cryo, curettage, cautery or topical retinoids
Candidiasis – severe and disseminated, treatment resistant involving oropharynx, vagina and skin – treat with topical nystatin and imidazole
Tinea
Syphilis – multiple ulcers and rapid progression to tertiary disease
Cryptococcosis – looks like facial molluscum contagiosum – treat fluconazole
Demodicosis – inflamed pruritic papular eruptions on face and upper trunk caused by demodex folliculitis
Scabies – severe, widespread, scaly, crusted eruptions but sometimes without severe itch – treat with permethrin lotion

Question 8

What inflammatory skin disorders are common in HIV?

Answer 8

Seborrheic dermatitis – widespread inflammatory red scaly patches on hairy areas and naso-labial folds and flexures – treat with ketoconazole shampoo
Acquired ichthyosis – scaly skin and keratoderma (thickened palms and soles)
Psoriasis – either new onset or cause pre-existing to flare
Eosinophilic folliculitis – intensely itchy papulopustular eruption of sterile pustules – treat with tacrolimus, topical steroids and phototherapy
Pruritic papular eruption (PPE) – symmetrical, red or skin coloured itchy papules.

Question 9

What nail and hair changes are seen in HIV?

Answer 9

Nail changes – Onychomycosis, nail pigmentation and Beau’s lines
Hair changes – diffuse alopecia or alopecia areata

Question 10

Which skin cancer are HIV patients particularly at risk of?

Answer 10

Increased risk of all skin cancers and especially Kaposi’ sarcoma. This occurs as a result of Herpes hominis virus 8 (HHV-8). Presents as purple papules or plaques in the skin and mucosa of any organ and metastasises to nodes.

Question 11

What is Bullous pemphigoid?

Answer 11

Autoimmune blistering disorder in the elderly due to IgG antibodies to hemidesmosome protein. Appears as tense blisters on inflamed normal skin. Mouth normally spared

Question 12

How is bullous pemphigoid confirmed?

Answer 12

Skin biopsy shows positive immunofluorescence for IgG and C3

Question 13

How is bullous pemphigoid managed?

Answer 13

Management – potent oral steroids such as clobetasol, prednisolone (plus bone and gastric protection). Heals without scarring but relapsing remitting disorder
Can also use topical corticosteroids, immunosuppressants and antibiotics

Question 14

What is pemphigus vulgaris

Answer 14

Affects younger people and occurs due to antibodies against desmoglein 3 leading to acantholysis (keratinocytes separating from each other). Common in the Ashkenazi Jewish population.

Question 15

How does pemphigus vulgaris present?

Answer 15

Mucosal ulceration is common and often is the presenting symptom. Appears as flaccid superficial blisters which rupture easily leaving wide spread erosions, these are typically painful but not itchy. Oral mucosa affected early on.

Question 16

How is pemphigus vulgaris managed?

Answer 16

Management – oral prednisolone. Rituximab and IV immunoglobulins in resistant cases

Question 17

What is vitiligo?

Answer 17

Typically occurs at the age of 20-30 and is an autoimmune condition resulting in destruction of melanocytes.

Question 18

How does vitiligo present?

Answer 18

Causes well demarcated patches of depigmented skin usually affecting the peripheries. Associated with Type 1 DM, Addison’s disease, autoimmune thyroid disorders, pernicious anaemia and alopecia areata.

Question 19

How is vitiligo managed?

Answer 19

Management – sun cream for affected areas, camouflage makeup , topical corticosteroids

Question 20

What is pruritis?

Answer 20

Medical term for an itch, can present along with lichenification (thickening of the skin) prurigo papules and nodules.

Question 21

What commonly causes pruritis?

Answer 21

Localised causes such as dermatitis, tinea, candida, and herpes zoster.
Metabolic causes – renal failure, liver disease, polycythaemia vera, Grave’s disease, iron deficient anaemia and paraneoplastic phenomena such as Hodgkin’s lymphoma
Specific skin diseases such as allergic dermatitis, psoriasis folliculitis etc.

Question 22

What investigations should you order in someone with pruritis?

Answer 22

FBC, Creatinine and U&E, LFTs, TFTs, ESR

HIV serology

Question 23

What is a lipoma?

Answer 23

Common, benign tumour of adipocytes. Generally seen un subcutaneous tissues and rarely in deep adipose tissue. Malignant transformation is extremely rare. They are most commonly seen in middle aged adults.

Question 24

How do lipomas feel?

Answer 24

Smooth, mobile, and painless

Question 25

How can lipomas be managed?

Answer 25

Observed

If causing problems surgical removal

Question 26

What features are suggestive of a sarcomatous change in a lipoma?

Answer 26

Size > 5cm
Increasing size
Pain
Deep anatomical location

All indicating an USS

Question 27

What is atopic eruption of pregnancy?

Answer 27

Is the commonest skin disorder found in pregnancy. It typically presents as an eczematous, itchy red rash. No specific treatment is needed.

Question 28

What is poly morphic eruption of pregnancy

Answer 28

Pruritic condition associated with last trimester. Lesions often first appear in abdominal striae. Management depends on severity: emollients, mild potency topical steroids and oral steroids may be used.

Question 29

What is Pemphigoid gestationis?

Answer 29

Pruritic blistering lesions. Often develop in peri-umbilical region, later spreading to the trunk, back, buttocks and arms. Usually presents 2nd or 3rd trimester and is rarely seen in the first pregnancy. Oral corticosteroids are usually required.

Question 30

What is Hereditary Haemorrhagic Telangiectasia?

Answer 30

Also known as Osler-Weber-Rendu syndrome, hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant condition characterised by multiple telangiectasia over the skin and mucous membranes. Twenty percent of cases occur spontaneously without prior family history.

Question 31

What are the diagnostic criteria for herditary haemorrhagic telangiectasia?

Answer 31

There are 4 main diagnostic criteria. If the patient has 2 then they are said to have a possible diagnosis of HHT. If they meet 3 or more of the criteria, they are said to have a definite diagnosis of HHT:

1. Epistaxis: spontaneous, recurrent nosebleeds
2. Telangiectasias: multiple at characteristic sites (lips, oral cavity, fingers, nose)
3. Visceral lesions: for example, gastrointestinal telangiectasia (with or without bleeding), pulmonary arteriovenous malformations (AVM), hepatic AVM, cerebral AVM, spinal AVM
4. Family history: a first-degree relative with HHT

Question 32

What is chondrodermatitis nodularis helicis

Answer 32

Common and benign condition characterised by the development of a painful nodule on the ear. It is thought to be caused by factors such as persistent pressure on the ear (e.g. secondary to sleep, headsets), trauma or cold. CNH is more common in men and with increasing age.

Question 33

How is chondodermatitis nodularis helicis managed?

Answer 33

Reducing pressure on the ear: foam ‘ear protectors’ may be used during sleep
Cryotherapy, steroid injection, collagen injection
Surgical treatment may be used but there is a high recurrence rate

Question 34

What is Acanthosis nigricans

Answer 34

Brown to black, poorly defined, velvety hyperpigmentation of the skin. Usually found in body folds such as the posterior and lateral folds of the neck, the axilla, groin, umbilicus, forehead, and other areas.

Question 35

What is the most common cause of acanthosis nigricans?

Answer 35

The most common cause of acanthosis nigricans is insulin resistance, which leads to increased circulating insulin levels. Insulin spill over into the skin results in its abnormal increase in growth (hyperplasia of the skin).

Question 36

What are other causes of acanthosis nigricans

Answer 36

Other Causes 
•	Gastrointestinal cancer
•	Diabetes mellitus
•	Obesity
•	Polycystic ovarian syndrome
•	Acromegaly
•	Cushing's disease
•	Hypothyroidism
•	Prader-Willi syndrome
•	Drugs: oral contraceptive pill, nicotinic acid

In the context of a malignant disease, acanthosis nigricans is a paraneoplastic syndrome and is then commonly referred to as acanthosis nigricans maligna. Involvement of mucous membranes is rare and suggests a coexisting malignant condition.

Question 37

What is erythema nodosum?

Answer 37

Inflammation of subcutaneous fat. Typically causes tender, erythematous, nodular lesions
usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs). Usually resolves within 6 weeks and lesions heal without scarring, but should investigate with a CXR and routine bloods.

Question 38

What causes erythema nodosum?

Answer 38

Causes
• Infection – streptococci, tuberculosis and brucellosis
• Systemic disease – sarcoidosis, inflammatory bowel disease and Behcet’s
• Malignancy/lymphoma
• Drugs – penicillins, sulphonamides and combined oral contraceptive pill
• Pregnancy