ReviewThe primary hyperoxalurias: A practical approach to diagnosis and treatment

- Calcium oxalate urolithiasis is common.
- Primary hyperoxaluria (PH) must be excluded in all patients presenting with calcium oxalate urolithiasis.
- Phenotypic variability in PH may delay a diagnosis.
- PH is an important cause of renal failure.
- Understanding phenotype/genotype correlations directs treatment and assists predictions for decline in renal function.

Although the primary hyperoxalurias (PH) are rare disorders, they are of considerable clinical importance in relation to calcium oxalate urolithiasis and as a cause of renal failure worldwide. Three distinct disorders have been described at the molecular level. The investigation of any child or adult presenting with urinary tract stones or nephrocalcinosis, must exclude PH as an underlying cause. This paper provides a practical approach to the investigation and diagnosis of PH, indicating the importance of distinguishing between the PH types for the purposes of targeting appropriate therapy. Conservative management is explored and the various transplant options are discussed.