RT Journal Article SR Electronic T1 ‘Tiger woman sign’ hypercalcaemia: a diagnostic challenge JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 73 OP 75 DO 10.7861/clinmed.2020-0878 VO 21 IS 1 A1 Muse, Adam A1 Cates, Matthew A1 Rogers, Patrick A1 Evans, Michael A1 Walker, Jonathan YR 2021 UL http://www.rcpjournals.org/content/21/1/73.abstract AB Hypercalcaemia is a common electrolyte abnormality with 90% of cases due to either primary hyperparathyroidism or malignancy. Other causes of hypercalcaemia often require careful consideration. We describe an approach to the assessment of hypercalcaemia, particularly where preliminary tests are inconclusive.This approach is illustrated by a case which posed a diagnostic challenge: a patient with significant hypercalcaemia due to acute atypical isolated sarcoid myositis. This case highlights an under-recognised clinical syndrome with distinct biochemical and radiological findings.