Inflammatory skin disease tutorial

Question 1

Ten minutes after eating a peanut butter sandwich this child developed facial swelling and a widespread, circinate (circular), erythematous rash on face, trunk and limbs.

1. What is the diagnosis?
2. What type of hypersensitivity reaction is involved?
3. What is the main chemical mediator?
4. What drug treatment would you consider?
   a) Right now?
   b) If she became tachycardic and developed breathing difficulties?

Answer 1

1. What is the diagnosis? Peanut allergy
2. What type of hypersensitivity reaction is involved? Immediate / type 1
3. What is the main chemical mediator? Histamine
4. What drug treatment would you consider?
   a) Right Now ? antihistamine
   b) If she became tachycardic and developed breathing difficulties? Intramuscular adrenalin (anaphylaxis treatment)

Question 2

This man has had various treatments for inflammation of Case 2 the auditory meatus (ear canal) on and off for years. A few days after having started a further course of “eardrops” which dripped onto his chest, he developed this skin reaction.

What is the diagnosis?

1. What hypersensitivity mechanism is involved?
2. What investigation would confirm the diagnosis?
3. What advice would you give the patient regarding future treatment?

Answer 2

What is the diagnosis? contact allergy to ear drops

1. What hypersensitivity mechanism is involved? delayed / type 4
2. What investigation would confirm the diagnosis? patch testing – to ear series including antibiotics, antifungals, anaesthetic, topical steroid, preservatives
3. What advice would you give the patient regarding future treatment? avoid known allergens

Question 3

Appreciate that skiin disease can present which can be the initial sign of internal disease

Answer 3

Appreciate this

Question 4

What is Acanthosis Nigricans associated with ?

Answer 4

Associated with malignancy of GI tract

Question 5

A 46 year old man with a history of heavy alcohol intake for 15 years has developed the signs shown: Yellowing of the skin (jaundice) Excoriation marks (secondary to itch / scratch) Abdominal swelling

Q1 Damage to which organ is responsible for these signs?

Q2 a) Why is he itchy?

b) Suggest a treatment that might relieve the itch?

Answer 5

Q1 Damage to which organ is responsible for these signs? liver

Q2 a) Why is he itchy? complex – though to be due to increased endogenous opioids which act as neurotransmitters in central nervous system. Bile acids may contribute.

b) Suggest a treatment that might relieve the itch ? Difficult – UVB phototherapy may help, cholestyramine to reduce bile acids, sedating antihistamine