A 34-year-old intravenous drug user is admitted with a purpuric rash affecting her legs. Blood tests reveal the following:
What is the most likely diagnosis?
Correct Answer D: Hepatitis C infection is associated with type II (mixed) cryoglobulinaemia, suggested by the purpuric rash, positive rheumatoid factor and reduced complement levels.
Cryoglobulinaemia: Immunoglobulins which undergo reversible precipitation at 4 deg C, dissolve when warmed to 37 deg C. One third of cases are idiopathic .
Three types:
Type I:
Type II:
Type III:
Symptoms (if present in high concentrations):
Tests:
Treatment:
A 59-year-old man with a history of gout presents with a swollen and painful first metatarsophalangeal joint. He currently takes allopurinol 400mg od as gout prophylaxis.
What should happen to his allopurinol therapy?
Correct Answer E: Gout: management:
Gout is a form of microcrystal synovitis caused by the deposition of monosodium urate monohydrate in the synovium. It is caused by chronic hyperuricaemia (uric acid > 450 μmol/l).
Acute management:
Allopurinol prophylaxis:
Indications for allopurinol*:
Lifestyle modifications:
*Patients with Lesch-Nyhan syndrome often take allopurinol for life.
A 34-year-old is diagnosed with chronic fatigue syndrome.
Which one of the following interventions is most useful?
Correct Answer A:
Chronic fatigue syndrome:
Diagnosed after at least 4 months of disabling fatigue affecting mental and physical function more than 50% of the time in the absence of other disease which may explain symptoms.
Epidemiology:
Fatigue is the central feature, other recognized features include:
Investigation:
Management:
Better prognosis in children
*children and young people only
A 68-year-old female presents with a two week history of intermittent headaches and lethargy. Blood tests reveal the following:
Correct Answer E: This is a classic history of temporal arteritis. Treatment should be started immediately with high dose steroids (e.g. prednisolone 1mg/kg/day) to reduce the chance of visual loss.
Temporal arteritis:
Temporal arteritis is large vessel vasculitis which overlaps with polymyalgia rheumatica (PMR). Histology shows changes which characteristically 'skips' certain sections of affected artery whilst damaging others.
Features:
Investigations:
Which one of the following cytokines is the most important in the pathophysiology of rheumatoid arthritis?
Correct Answer D: Rheumatoid arthritis - TNF is key in pathophysiology.
Tumour necrosis factor : Tumour necrosis factor (TNF) is a pro-inflammatory cytokine with multiple roles in the immune system.
TNF is secreted mainly by macrophages and has a number of effects on the immune system, acting mainly in a paracrine fashion:
TNF-alpha binds to both the p55 and p75 receptor. These receptors can induce apoptosis. It also cause activation of NFkB.
Endothelial effects include increase expression of selectins and increased production of platelet activating factor, IL-1 and prostaglandins.
TNF promotes the proliferation of fibroblasts and their production of protease and collagenase. It is thought fragments of receptors act as binding points in serum.
Systemic effects include pyrexia, increased acute phase proteins and disordered metabolism leading to cachexia.
TNF is important in the pathogenesis of rheumatoid arthritis - TNF blockers (e.g. infliximab, etanercept) are now licensed for treatment of severe rheumatoid.
TNF blockers:
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