Which of the following is a radiolucent stone?: (A) Uric acid, (B) Oxalate, (C) Cysteine, (D) Triple phosphate
Answer is A. Ans: a (Uric acid) Ref: Bailey and Love, 24th ed, p. 1317Pure uric acid stones are radiolucent and appear in an excretory urogram as filling defects.Uric acid stones if contain calcium, will cast a faint radiological shadow.Examples for radiolucent stones* Uric acid* Dihydroxy adenine* Orotic acid* Xanthine* Allopurinol* Triamterine and Indinavir induced stones.