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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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The most common underlying aetiology of primary hyperparathyroidism is
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The correct answer is  The underlying aetiology of PHPT is usually a solitary parathyroid adenoma, however, in a small number of patient (2-4%), there are double adenomas. It may occur in a sporadic fashion or it can be familial (MEN type 1 or type 2A, hyperparathyroidism-jaw tumour syndrome (HPT-JT)Ref: Bailey and Love 27e pg: 826