dermatology Flashcards
What does t cell lymphoma look like
mycosis fungoides, a cutaneous T cell lymphoma.
The disease presents as a pruritic eczematous rash (the pre-malignant stage) and develops telangiectasias and areas of ‘cigarette paper’ atrophy.
As malignancy develops, nodular lesions appear and proceed to become necrotic.
cutaneous features of dermatomyositis
heliotrope rash (violet/blue lesions around eyes)
guttrons
Malar erythema
Poikiloderma (i.e. variegated telangiectasia, hyperpigmentation) in a photosensitive distribution
Violaceous erythema on the extensor surfaces, and
Periungual and cuticular changes
causes of erythema nodosum
palpable nodular
TB
saroidosis
Infections (such as Streptococcus infections)
Drugs (sulphonamides, oral contraceptive pill)
Inflammatory bowel disease and
Behçet’s.
Apart from the chest x ray, the following are also important:
A throat culture
Antistreptolysin-O test (ASOT)
Mantoux test
Biochemistry
fishy, thin, vaginal discharge
BV
post coital smell
metrnidazole
pH >4.5
side effect of ethambutol
optic neuritius
normal fundoscopy
Beaus lines
Beau’s lines, a benign nail condition that presents as a jagged transverse groove on the nail plate corresponding to an episode of nail growth arrest, which can occur during an episode of severe medical illness. It usually affects several nails.
nail psoriasis
Nail psoriasis presents with pitting, onycholysis, subungual debris and yellowish nail discolouration.
fungal nails
Fungal nail infections present with thickening and discolouration of the nail plate with prominent subungual debris. It usually only affects one or several nails.
side effects of minocycline for acne
Minocycline treatment can lead to discolouration of nails.
features of PCP
Several days/weeks of increasing dyspnoea
Dry cough
Marked oxygen desaturation with exercise.
Signs of immunocompromise
Clear CXR
bilaeral crackles
side effects of isonia
side effects of isoniazid therapy include hepatits, peripheral neuritis (pyridoxine given prophylactically) and a systemic lupus erythematosus (SLE)-like syndrome.
telangiectasia, small mouth, beaking of nose
Systemic sclerosis, depsotion of connective tissue in skin and organs
cutaneous larva migrans
causes: antimal hookwoors, ancylostoma braziliense, firsct contact with dog or cat faexea, when sunbathing
acute infection with nematodes: strongloides stercoralis, necator americanus and ancylostoma duodenales
larvae burrow in dermo-epidermal junction
pruritus, raised sepiginoous erthematous rash that migrates at a rate of 1cm/day
Rx: topical thiabendazole or oral albendazole
scaly, hyperpigmented, erythematous plaques on sun-exposed areas and may lead to severe scarring.
discoid lupus erythematous
rx: Topical potent corticosteroids Topical calcineurin inhibitors Intralesional corticosteroids Anti-malarials, and Oral corticosteroids.
Behcets disease
- recurrent oreal ulceration
- recurrent genital ulceration
- Iritis
Other features: fever abdo oain diarrhoea episcleritis polyarteritis arterial and venous thrombosis pericarditis pustules at injection sites
HLAB5, HLAB12
Treatment: colchicie, steroids
cutaneous photosensitivity. Bullae develop on sun-exposed areas and lesions heal slowly, leaving scars.
PCT.
Porphyria cutanea tarda (PCT) is associated with deficiency of hepatic uroporphyrinogen (URO) decarboxylase.
Porphyrins are increased in liver, plasma, urine and stool. Porphobilinigen (PBG) is normal.
Factors contributing to PCT are alcohol (the commonest cause), excess iron and excess oestrogens.
presents as a dark brown to black plaque or nodule on acral sites.
Acral (peripheral) lentiginous melanomad
most commonly presents as an ulcerated nodule with pearly, rolled edges with telangiectasias.
Basal cell carcinoma
umbilicated, pearly papules 2-5 mm in diameter are seen in patients with advanced HIV/AIDS (CD4 count less than 200 cells/mm3).
molloscum contangiosum
caused by a DNA pox virus called molluscum contagiosum virus (MCV).
They commonly occur on the face, especially near the eyelids; they also occur on genitals and trunk.
They should be treated with cryotherapy, liquid nitrogen or curettage.
what is pemphigus vulgaris?
Blisters are thin-walled and rupture easily (intact blisters are rarely seen). Large surface areas of the body can be affected and the mortality without treatment is high.
deposition of immunoglobulin (IgG) directed against to keratinocyte desmosomes and to desmosome-free areas of the keratinocyte cell membrane, resulting in a ‘chicken wire’ appearance. The binding of autoantibodies results in a loss of cell-to-cell adhesion, a process termed acantholysis.
what is pemphigoid
large tense intact blisters. Immunofluorescence of pemphigoid shows deposition of IgG and complement at the dermo-epidermal junction.
describe pre-tibial myxoedema
painless, raised pinkish patches on dorsum of shins, ankle, foot
associated with graves
describe malignant melanoma
ususaly multipigmented dark , assymetrical lesions with irregular borders which may enlarge rapidly and bleed.
describe karposis sarcoma
Kaposi’s sarcoma is casued by the Human Herpes 8 virus and is only really seen in severe prolonged immunosupprssed patients.
