More than 30 years ago, Maurice Pappworth cautioned against the sin of “diagnostic greed”. “Overwhelming evidence is not essential for correct diagnosis, and the absence of some expected symptom or sign often does not invalidate an otherwise reasonable diagnosis.”¹

Many junior clinicians have difficulty formulating a differential diagnosis after history-taking and clinical examination. The sin of diagnostic greed is common. There is little difficulty diagnosing acute pulmonary embolism if a patient is a returned air traveller and has pleuritic chest pain, haemoptysis, hypoxaemia and an ECG showing S₁Q₃T₃. Likewise, coeliac disease is easily diagnosed if a child has chronic diarrhoea, failure to thrive, iron deficiency anaemia and the itchy rash of dermatitis herpetiformis. However, such “full-house” clinical presentations are rare. …