Dermatology Flashcards
You are working in General Practice and see a 24 year old man with a likely diagnosis of pityriasis rosea. What most likely precedes this condition?
(A) Bacterial Infection (B) Viral Infection (C) Antibiotics (D) Alcohol (E) Dermatophyte Fungal Infection
(B) Viral Infection
Pityriasis Rosea often follows viral infection. Streptococcal throws infection tends to trigger guttate psoriasis, dermatophyte fungal infection tends to result in pityriasis versicolor. Antibiotics are not a recognised trigger for pityriasis Rosea. Acne rosacea is often triggered by sun exposure, hot drinks or exercise. There is a misconception it is triggered by alcohol which can be distressing to those suffering.
A 28 year old Caucasian man presents with itchy red spots on his abdomen, back and arms, which he reports appeared quite suddenly. He has no significant past medical history, but states he had a sore throats a few weeks ago. On examination you notice he has a white pus-like discharge over his palatine tonsils. He states he had a similar rash last winter when he had a sore throat
Which of the following is the most likely diagnosis?
(A) Drug eruption (B) Urticaria (C) Guttate Psoriasis (D) Lichen Planus (E) Discoid Eczema
(C) Guttate Psoriasis
Streptococcal throats infection may precipitate psoriasis (particularly guttate psoriasis). Patients with frequent exacerbation of guttate psoriasis due to streptococcal threat infections may benefit from tonsillectomy.
Streptococcal throat infection may precipitate guttate psoriasis. The other options are important differentials to consider, but given the relation to a sore throat, the sudden onset and the fact that the question does not mention any medications taken (drug eruption) or blanching nature of the rash (urticaria), guttate psoriasis is most likely.
A 34 year old man with a history of polyarthralgia, back pain and diarrhoea is found to have a 3 centimetre lesion on his shin which is starting to ulcerate. What is the most likely diagnosis?
(A) Systemic shigella infection (B) Syphilis (C) Metastatic Colon Cancer (D) Erythema Nodosum (E) Pyoderma Gangrenosum
(E) Pyoderma Gangrenosum
This patient is likely to have ulcerative colitis, which has a known association with large joint arthritis, sacroilietis and pyoderma Gangrenosum.
Pyoderma Gangrenosum typically affects the lower limbs, presents as an initially small, red papule, later becomes a deep red, necrotic ulcer with a violaceous border and may be accompanied by systemic features such as fever and myalgia.
Management : the potential for rapid progression is high in most patients and most doctors advocate oral steroids as first line treatment.
Other immunosuppressant therapy, for example ciclosporin and infliximab have a role in difficult cases.
An 8 year old boy presented with a painless growth on the superotemporal aspect of his orbit. It was smooth on examination and produced no visual disturbances. Following excision it was found to be lined by squamous epithelium and hair follicles. Which of the following lesions most closely matches these findings?
(A) Dermoid Cyst (B) Desmoid Tumour (C) Lipoma (D) Sebaceous Cyst (E) Schwannoma
(A) Dermoid cyst
Dermoid cysts are embryological remnants and may be lined by hair and squamous epithelium (like teratomas). They are often located in the midline and may be linked to deeper structures resulting in a dumbbell shape to the lesion. Complete excision is required as they have a propensity to recurr locally if not excised.
Desmoid rumours are a different entity, they most commonly develop in ligaments and tendons. They are also referred to as aggressive fibromatosis and consist of fibroblast dense lesions (resembling scar tissue). They should be managed in a similar manner to soft tissue sarcomas.
Which of the following skin disorders is not commonly seen with Systemic Lupus Erythematous (SLE)?
(A) Keratoderma blenorrhagia (B) Alopecia (C) Livedo reticularis (D) Photosensitivity (E) Butterfly Rash
(A) Keratoderma blenorrhagia
Skin manifestations of SLE ……… LAPD
Livedo reticular is (net like rash)
Alopecia
Photosensitivity (butterfly rash)
Discoid Lupus
What is the A-E assessment of suspicious pigmented skin lesions?
A - Asymmetry B - Border irregularities C - Colour Variation D - Diameter >6mm E - Evolving
What is the standard treatment for melanoma?
Urgent excision with narrow margins followed by a wider local excision. Melanoma is not very chemo or radiosensitive.
What does the MMRISK mnemonic for skin cancer stand for?
Moles - atypical Moles - many Red hair Inability to tan Sunburn previously Kin (family history)
