Case History

A 78 year old man was admitted to hospital with a history of general malaise, joint pain in his shoulders and knees, and a rash over his hands (figure 1), feet, and lower legs. He had previously been well up to 3 weeks before admission, when his general practitioner had started him on captopril (an angiotensin converting enzyme (ACE) inhibitor) for hypertension. Physical examination showed a pyrexia of 38⁰C.

On auscultation a pansystolic murmur radiating to the axilla was noted.

Questions

(1) What abnormality can you see in figure 1?
(2) What type of rash does he have ?
(3) What important diagnosis needs to be considered ?
(4) Give 5 causes of this rash.

Answers

(1) Nail fold infarct on thumb and purpuric rash on index finger and dorsum of hand.
(2) Vasculitis inflammation of the blood vessels, in the case of the nail fold infarct due to small vessel vasculitis affecting the terminal digital arteries.
(3) Bacterial endocarditis
(4) Causes of vasculitis

• allergic - drugs, food, inhaled allergens
• carcinoma
• connective tissue diseases - rheumatoid arthritis, polyarteritis nodosa, dermatomyositis, systemic lupus erythematosus, Wegener's granulomatosis, mixed connective tissue disease
• cryoglobulins
• emboli - subacute bacterial embolism
• infections - bacterial, fungal, viral
• infestations
• idiopathic.

Discussion

Vasculitis is inflammation of the blood vessels. The primary event initiating inflammation may be an abnormality of the blood, the vessel wall, or the tissues adjacent to the vessel. Small blood vessels with slow rates of flow are usually affected. The stagnant circulation in the capillaries and venules of the legs make these common sites for vasculitis. Changes include increased permeability causing oedema, visible urticarias, and blisters; leakage of blood cells leading to purpura and haemorrhagic blisters; occlusion of blood vessels with resulting ischaemia and necrosis. Vasculitis can affect all organs. The kidneys, lungs, and joints are often affected in addition to skin.

Investigation showed no evidence of a bacterial endocarditis. The British National Formulary indicated that some ACE inhibitors cause a symptom complex which include fever, arthralgia, myalgia ,and vasculitis. Therefore his ACE inhibitor was discontinued.

Within 24 hours his temperature had settled, and at 4 weeks' review in outpatients his vasculitis had completely resolved. He has remained well at 6 month follow up.