Systemic Disease Flashcards
Name some genetic diseases which may have some skin manifestations?
Tuberous Sclerosis
Neurofibromatosis
Name some endocrine and metabolic diseases which may have some skin manifestations?
Diabetes Thyroid disease Addison's Disease Tumours with endocrine effect Porphyrias Cushing's syndrome Parathyroid disease
Name some skin signs that may be present in diabetes?
- Infection
- Ulcers
- Xanthomata
- Necrobiosis Lipoidica
- Acanthosis nigricans
- Diabetic dermopathy – brown atrophic lesions legs
- Therapy - Effects of Insulin, Oral treatments
What is erysipelas and what causes it?
Acute infection of the upper dermis and superficial lymphatics typically with a skin rash and is usually caused by a streptococcal infection (Strep. pyogenes which is a beta-haemolytic group A strep is the most common cause)
What is xanthomata?
Deposition of yellowish cholesterol-rich material that can appear anywhere in the body in various disease states
Most patients with necrobiosis lipoidica will have what condition?
Diabetes mellitus (can also be associated with rheumatoid arthritis)
Thyroid hormone does what in the skin?
- Promotes fibroblast activity
- Regulates epidermal differentiation
- Essential for hair formation and sebum production
- Effects on skin perfusion
What effects might hyperthyroidism have on the skin?
Warm, moist smooth skin Facial flushing, palmar erythema Fine, thin hair. Diffuse alopecia Hyperhidrosis 5% - nail changes 2% - hyperpigmentation Pruritus Graves disease – pretibial myxoedema also present
Explain the pathophysiology of pretibial myxoedema?
Fibroblasts stimulated by autoantibodies to produce high amounts of glycosaminoglycans which accumulates in the dermis
What effects might hypothyroidism have on the skin?
Cold, dry pale skin
Xerosis – may resemble acquired ichthyosis
Carotenaemia - ↓ capacity of liver to synth. Vit A
Dry, coarse brittle hair, diffuse alopecia
Loss of lateral 1/3 eyebrow
Thickened brittle nails
Generalised myxoedema – disappears with correction of
T4 level
Autoimmune causes may be assoc. with alopecia areata, PA ETC.
What is Addison’s disease?
Primary adrenocortical insufficiency
What are some of the signs/symptoms of Addison’s disease?
Diffuse hyperpigmentation
Palmar crease pigmentation
Buccal pigmentation
Why is there an increase in pigmentation in Addison’s disease?
Absence of normal glucorticoid feedback to pituitary leads to increased ACTH + MSH production leading to increased melanogenesis
Name a tumour which may cause hirsutism?
Ovarian tumour
What syndrome may cause hirsutism?
Polycystic ovarian syndrome
What is the treatment of discoid lupus erythematous?
Sun avoidance
Potent/very potent steroids
Oral antimalarials
What are the skin features of systemic lupus erythematous (SLE)?
- Butterfly rash - present in 85%
- UV sensitivity
- Nail fold capillaries prominent
- May have widespread DLE type rash
Is SLE more common in males or females?
Females (7:1 ratio)
What is systemic sclerosis?
Thickening of the skin caused by accumulation of collagen
What are the skin features of systemic sclerosis?
Pinched mouth – radial furrows Beaked nose Matt - like facial telangectasia Sclerodactyly Periungual telangiectasia Raynaud’s phenomenon in 85%
Dysphagia
Is systemic sclerosis more common in males of females?
Females (4:1 ratio)
Which autoantibodies may be present in systemic sclerosis?
Anti-nuclear antibody (+ANA)
Anti-centromere antibody
What are the skin features of dermatomyositis?
Photosensitivity rash like that of L.E.
Heliotrope oedema of eyelids
Linear finger rash with Gottron’s papules
Which autoantibody may present in dermatomyositis?
+ANA
