Calyceal microlithiasis or more specifically renal calyceal microlithiasis is defined as <3 mm hyperechoic foci noted within the renal calyces on gray scale ultrasonography 1. It has been considered as a precursor for renal stone formation.
The patient may be asymptomatic or may present with abdominal pain, dysuria and/or hematuria.
Patients may or may not have hypercalciuria
Ultrasound is the first and routinely used investigation to diagnose these tiny hyperechoic foci in the renal calyces.
It should not be used synonymously to Randall's plaque which characteristically have been considered as having >50% surface covered by renal paranchyma and are not in the calyces.
- 1. Polito C, Cioce F, La Manna A et-al. Renal calyceal microlithiasis: clinical presentation may precede sonographic evidence. Clin Pediatr (Phila). 1999;38 (9): 521-4. Pubmed citation