Three Tesla magnetic resonance imaging detects oxalate osteopathy in patients with primary hyperoxaluria type I.

Background: With declining kidney function and therefore increasing plasma oxalate, patients with primary hyperoxaluria type I (PHI) are at risk to systemically deposit calcium-oxalate crystals. This systemic oxalosis may occur even at early stages of chronic kidney failure (CKD) but is difficult to detect with non-invasive imaging procedures.

Methods: We tested if magnetic resonance imaging (MRI) is sensitive to detect oxalate deposition in bone.

Diet-related urine collections: assistance in categorization of hyperoxaluria.

Hyperoxaluria, one of the major risk factors for calcium oxalate urolithiasis and nephrocalcinosis, causes significant morbidity and mortality and should therefore be detected and treated as soon as possible. An early, consequent and adequate evaluation, but also a distinction between primary (PH) and secondary hyperoxaluria (SH) is therefore essential. We evaluated the usefulness of three consecutive 24-h urine collections under different diets [usual diet, (A), low oxalate diet, (B), high oxalate diet, (C)] to prove SH, or to find evidence of PH by changes in urinary oxalate excretion (Uox).

Plasma oxalate levels in primary hyperoxaluria type I show significant intra-individual variation and do not correlate with kidney function.

Background: Primary hyperoxalurias are rare diseases with endogenous overproduction of oxalate, thus leading to hyperoxaluria, hyperoxalemia, urolithiasis, and/or nephrocalcinosis and eventually early kidney failure. Plasma oxalate (POx) is an important diagnostic parameter in clinical studies on primary hyperoxaluria (PH). This is especially the case in kidney failure, where urinary parameters are no longer suitable.