Dermatology in systemic disease Flashcards
What is necrobiosis lipoidica?
Necrobiosis lipoidica is a rare granulomatous skin disorder which can affect the shin of insulin-dependent diabetics, although it may occur in non-diabetic subjects as well. The cause is unknown.
What are the clinical features of necrobiosis lipoidica?
Typically in necrobiosis lipoidica, one or more yellowish brown patches develop slowly on the lower legs over several months.
The centre of the patch becomes shiny, pale, thinned, with prominent blood vessels (telangiectasia).
What is the treatment for necrobiosis lipoidica?
Topical steroids, usually under a plastic occlusive dressing.
Intralesional steroid injections or steroid tablets
What is granuloma annulare?
Granuloma annulare (GA) is a common skin condition in which there are smooth discoloured plaques. They are usually thickened and ring-shaped or annular in shape. Granuloma annulare is more correctly known as necrobiotic papulosis.
What is the cause of granuloma annulare?
Granuloma annulare is a delayed hypersensitivity reaction to some component of the dermis. Inflammation is mediated by tumour necrosis factor alpha (TNFα). The reason that this occurs is unknown.
Granuloma annulare can be either localised or widespread? Which systemic disease is associated with each?
Localised granuloma annulare is sometimes associated with autoimmune thyroiditis, but it does not clear up with thyroid replacement. Extensive granuloma annulare is sometimes associated with diabetes mellitus, hyperlipidaemia, and rarely with lymphoma, HIV infection and solid tumours.
What is the treatment for granuloma annulare?
In most cases of granuloma annulare, no treatment is required because the patches disappear by themselves in a few months, leaving no trace. However, sometimes they persist for years. Treatment is not always successful.
Topical corticosteroid or intralesional steroid injection is usually chosen.
What is pyoderma gangrenosum?
Pyoderma gangrenosum presents as a rapidly enlarging, very painful ulcer. It is one of a group of autoinflammatory disorders known as neutrophilic dermatoses.
What systemic disease are associated with pyoderma gangrenosum?
- Inflammatory bowel disease
- RA
- Chronic active hepatitis
- GPA
What are the clinical features of pyoderma gangrenosum?
- Pyoderma gangrenosum usually starts quite suddenly, often at the site of a minor injury.
- It may start as a small pustule, red bump or blood-blister.
- The skin then breaks down resulting in an ulcer. The ulcer can deepen and widen rapidly.
- Characteristically, the edge of the ulcer is purple and undermined.
- Pyoderma gangrenosum is usually very painful.
- Several ulcers may develop at the same time or over months to years.
What are the treatment options for small and large pyoderma gangrenosum lesions?
- Small- Potent topical steroid ointment or Tacrolimus ointmen
- Large-
- Oral prednisone for several weeks or longer, or intermittent intravenous methylprednisolone for 3–5 days
Ciclosporin
Biologic agents: success with infliximab, adalimumab, etanercept and ustekinumab is reported in a small number of cases (used off-label).
What is acanthosis nigricans?
Acanthosis nigricans is a skin disorder characterised by darkening (hyperpigmentation) and thickening (hyperkeratosis) of the skin, occurring mainly in the folds of the skin in the armpit (axilla), groin and back of the neck.
What is acanthosis nigricans associated with?
The cause for acanthosis nigricans is still not clearly defined but it appears to be related to insulin resistance.
What are the 4 key components of acanthosis nigricans management?
- Correct hyperinsulinaemia through diet and medication
- Lose weight with obesity-associated acanthosis nigricans
- Excise or treat underlying tumour
- Stop offending medicines in drug-induced acanthosis nigricans
