Skin manifestations of systemic disease

Question 1

Dermatological side effects of medications

Answer 1

Urticaria
Erythema multiforme
stevens-johnson syndrome

Question 2

Dermatological side effects of Autoimmune diseases

Answer 2

bullous pemphigoid
dermatitis herpetiformis
lupus erythematosus

Question 3

Dermatological side effects of Endocrine diseases

Answer 3

acanthosis nigricans & necrobiosis lipodica

Question 4

Pyoderma gangrenosum

Answer 4

Neutrophilic dysfunction leading to deep, persistent and necrotic ulcers which may start as papules but progress to chronic ulcers. 50% associated with other autoimmune conditions (UC/Crohns, lupus, leukemia)

Question 5

Erythema nodosum

Answer 5

An autoimmune inflammation of fat on the shins causing tender hypodermic nodules and may be associated with joint pains and fever beforehand. Usually resolves->3-6wks. Strep, TB, IBD, lymphoma, pregnancy

Question 6

Acanthosis nigricans

Answer 6

A brown to black, poorly defined, velvety hyper pigmentation of the skin. It is usually found in body folds
May be due to obesity, endocrine dysfunction or cancer

Question 7

dermatitis herpetiformis

Answer 7

a chronic blistering condition. intensely itchy, chronic papulovesicular eruptions, usually distributed symmetrically on extensor surfaces
Autoimmune condition related to celiac (IgA deposits). Treat with gluten-free diet and dapsone.

Question 8

bullous pemphigoid

Answer 8

A type II hypersensitivity reaction which can be acute or chronic - bullae form between the dermis and the epidermis. cause unknown but linked to drugs or UV exposure

Question 9

Erythema multiforme

Answer 9

An idiopathic condition of mildly itchy ‘target lesions’ starting on the backs of the hands/feet and spreading to the trunk due to IgM deposition which is likely autoimmune but may be brought on by HSV infection/bacteria(TB or Strep) /drugs (penicillin, carbamazepine, allopurinol, NSAIDs, COC, nevirapine) /SLE/sarcoid or cancers

Question 10

Urticaria

Answer 10

pale red, raised, itchy bumps (hives) due to mast cell degranulation
Related to angioedema. Most commonly caused by Aspirin.

Question 11

stevens-johnson syndrome

Answer 11

a mild form (10%) of Toxic epidermal necrolysis - a antibody mediated condition where cell death causes blistering and erosions with wide spread separation of the epidermis from the dermis – linked to drug reactions, infections (HIV) and cancers. In some cases arises due to very severe erythema multiforme.

Question 12

Necrobiosis lipoidica

Answer 12

Necrosis of subcutaneous fat in diabetes and RA

presents with a hardened, raised area which is non-tender but may ulcerate after trauma – linked to microangiopathy

Question 13

Erythema toxicum neonatorum

Answer 13

A rash affecting 10-50% of newborns between 3 days and 2wks. start on the trunk and an involve the proximal limbs and face. small erythematous papules & vesicles surrounded by blotchy erythema

Question 14

Skin rashes after taking drugs

Answer 14

1% of OP prescriptions and 2-5% of OTC - very rarely fatal
Particularly - NSAIDs, Abx, anticonvulsants, chemotherapy
Usually symmetrical - 2-20days after taking drug

Question 15

Rashes in lupus

Answer 15

Discoid lupus rashes – 55-90% will have butterfly rash

Photosensitive

Question 16

Pretibial myxoedema

Answer 16

deposition of hyaluronic acid in the skin associated with graves disease

Question 17

Vitiligo

Answer 17

30% familial and associated with other autoimmune disorders (addisons, DM type I, thyroid problems)
progressive depigmentation of the skin due to melanocyte dysfunction

Question 18

Alopecia areata

Answer 18

spontaneous, discrete loss of hair from an area without skin inflammation linked to T cell autoimmune activity
Normally self limiting and non-scarring. Regrows in 50% within 1yr and 80-90% eventually. Topical corticosteroids or Minoxidil can be used.

Question 19

Paraneoplastic dermatological signs

Answer 19

Erythema gyratum repens - lung, breast, uterus, bladder GI carcinoma
Sweets syndrome – haematological cancers
Necrolytic migratory erythema – glucagonoma

Question 20

Pemphigus Vulgaris

Answer 20

an autoimmune condition more common in ashkenazi jews which presents with oral ulceration (50-70%) leading to flaccid skin vesicles & bullae. Treat with steroids and immunosuppression.

Question 21

Polymorphic eruption of pregnancy

Answer 21

Pruritic condition associated with the 3rd trimester. May appear in abdominal striae. Emollients, topical steroids and oral steroids may be used.

Question 22

Pemphigoid gestationis

Answer 22

Pruritis blistering lesions which develop in the peri-umbilical region in the 2nd or 3rd trimester of multips, Spreads to trunk, back, buttocks and arms. Oral steroids are usually required.

Question 23

Epidermolysis Bullosa

Answer 23

A congenital cause of skin bullae. A variety of forms exist of varying severity.

Question 24

Drug Causes of bullous rashes

Answer 24

Barbiturates and furosemide

Question 25

Arterial ulcers

Answer 25

Painful and occur on the toes or heel. May be areas of gangrene. Cold with no palpable pulses. Low ABPI measurements.

Question 26

Venous Ulcers

Answer 26

Will be painless and above the ankle. Treat with compression banding. Due to venous hypertension/insufficency. Surrounding skin will have features - eczema, oedema, brown discolouration, etc

Question 27

Features of Acute febrile neutrophilic dermatosis (Sweet’s syndrome)

Answer 27

Fever, leukocytosis, tender erythematous well demarcated papules and plaques with neutrophil granulocyte infiltrates

Question 28

Associations of sweet’s syndrome

Answer 28

20% assoc w/malignancy esp AML
strep
IBD
Pregnancy
Treatment with haematopoietic growth factors (eg use in leukaemia)

Question 29

Investigations in sweet’s syndrome

Answer 29

Neutrophilia (moderate)
^ESR
^Alkaline phosphate
Skin biopsy- polymorphonuclear leukocytes with nuclear fragmentation and histiocytotic cells

Question 30

Treatment of sweet’s syndrome

Answer 30

Prednisolone