Skin and Systemic Disease

Question 1

What is erythema nodosum?

What are the presenting features?

What is the treatment?

Answer 1

Presents with:

=> Painful, tender, dusky bruise like swellings over the shin

=> Fades over a few weeks

=> Most common in young women

=> Assoc. arthralgia, malaise, fever, inflammation in deeper dermis & subcutaneous fat

Management:

=> symptomatic relief with NSAIDs, light compression socks and rest

=> Treat underlying cause

=> Persistent cases = treat with anti-inflammatory i.e. colchicine or prednisolone

Question 2

What are the causes of erythema nodosum?

Answer 2

NODOSUM mneumonic:

NO cause i.e. idiopathic (60%)

Drugs i.e. sulphonamides, oral contraceptive pill

Oral contraceptives

Sarcoidosis

Ulcerative colitis ; crohn’s disease ; Bechet’s

Microbiology i.e. streptococcal infection, TB, bacterial, fungal causes

Question 3

What is erythema multiforme?

Answer 3

Acute self-limiting risk characterised by distinctive ‘target lesions’ on the distal limbs, palms and soles

=> concentric rings of erythema with a dusky centre which can blister

=> Inflammation/ulceration of mouth, lips & other mucosal sites

Erythema multiforme major
=> severe mucosal ulceration
=> systemic symptoms
=> fever

Management:
=> supportive with analgesia and parenteral fruits until dysphagia has resolved

Question 4

What causes erythema multiforme?

Answer 4

Herpes simplex virus = most common

Drugs i.e. anticonvulsants

Idiopathic (50%)

Mycoplasma pneumoniae

Question 5

Erythema multiforme major is on a spectrum with Steven Johnson’s syndrome and TEN:

1. Erythema multiforme major

=> 3-ring target lesions, often hands & feet

=> Mucosal lesions

=> recent infection i.e. herpes simplex virus, mycoplasma

2. Stevens-Johnson syndrome (SJS)

=> Scattered macules/blisters over face. trunk, proximal limbs (<10% of body surface)

=> Rarely 2-ring target lesions

=> Mucosal lesions

=> Systemic symptoms i.e. fever, skin tenderness, recent drug exposure

Answer 5

3. Toxic epidermal necrolysis (TEN)

=> Scattered macules/blisters over face, trunk, proximal limbs

=> >30% of body surface area

*same as SJS but >30% body

=> Mucosal lesions

=> Systemic symptoms i.e. fever, skin tenderness, recent drug exposure

=> Respiratory & gastrointestinal lesions

=> Hypotension

=> Decreased consciousness

Question 6

What is pyoderma gangrenosum?

Answer 6

Rare ulcerating skin lesion of unknown cause

Assoc. with inflammatory bowel disease most commonly + inflammatory arthritis and haematological malignancies

Painful nodules that rapidly turn into enlarging purulent ulcers (pyoderma) with a purple edge

May occur spontaneously or post-operatively in a surgical wound / stoma

Skin lesions = rich in neutrophils

Clinical diagnosis as histological features are non-specific

Management: systemic therapy with moderate to high dose systemic corticosteroids ± cyclosporin
=> Anti-TNF therapy i.e. infliximab for refractory cases

Question 7

What is Behcet’s syndrome?

Answer 7

Inflammatory disorder characterised by recurrent oral ulcers and eye lesions, genital ulcers or skin lesions

=> erythema nodosum

=> thrombophlebitis

Question 8

What is sarcoidosis?

What are the skin presentation of sarcoidosis?

Answer 8

Sarcoidosis = multisystem granulomatous disorder of unknown aetiology

Skin involvement in 20-30%
=> red-brown papule, nodules and plaques

=> Hypo-/hyperpigmented especially in dark skin

=> erythema nodosum in acute sarcoidosis

Question 9

Endocrine disease skin presentation:

1. Thyroid disease:
   i. Hypothyroidism: cold, dry skin and brittle hair with diffuse thinning and loss of outer 1/3 eyebrows

ii. Hyperthyroidism: hyperhidrosis, onycholysis and diffuse alopecia
=> Graves disease: pretibial myxoedema = non-pitting infiltration, plaques on the shins

2. Cushing’s syndrome: due to high cortisol

=> hirsutism, central obesity, moon face buffalo hump

=> purple striae, skin atrophy, telangiectasia

=> increased susceptibility to folliculitis / candidiasis

*striae’s caused by rupture in dermal collagen & elastic tissue - common over the abdomen, hips and breasts female puberty and lumbosacral area in adolescent males => fade from pink/purple to pale/silvery lines

3. Flushing:
   => pathological cause = carcinoid syndrome (+other neuroendocrine tumours)

Answer 9

4. Diabetes mellitus: mediated by hyperglycaemia + hyperinsulinaemia

=> fungal infection e.g. candidiasis

=> bacterial infection e.g. recurrent boils

=> arterial and neuropathic ulcers

=> poor / delayed healing

=> xanthomas

=> diffuse granuloma annulare

=> necrobiosis lipoidica - spreading erythema over shin which becomes yellow-is and trophic in the centre and may ulcerate

5. Acanthosis nigricans:
   => thickened, hyper pigmented, velvet-textured skin around large flexures

=> most common + mildest form assoc. with obesity +& insulin resistance

=> gastrointestinal malignancies

Question 10

Causes of pruritus

1. Iron deficiency anaemia
2. Malignancy (esp. lymphoma)
3. Diabetes mellitus
4. Chronic kidney disease
5. Chronic liver disease (esp. primary biliary cholangitis)
6. Thyroid disease
7. HIV
8. Polycythaemia vera

Answer 10

1. Chronic liver disease:

=> jaundice, palmar erythema, spider nave, leuconichia and hyperpigmentation

=> common in cholestatic disease

Question 11

What is amyloidosis?

What are the skin presentations?

Answer 11

Amyloid (an abnormal protein) deposits in organs + interferes with normal function

~50% have skin involvements

=> macroglossia (amyloid deposits in the oral cavity)

=> petechiae & purpura (amyloid deposits in vessels makes it frail)

=> purpura in periocular skin and large flexors

Question 12

What is scleroderma?

Answer 12

Thickening or hardening of the skin due to abnormal dermal collagen

=> systemic sclerosis

=> morphea (localised cutaneous scleroderma) - confined to skin or subcutis

=> bluish-red thickened plaque with a shiny white indurated or atrophic centre