ESPN 53rd Annual Meeting

ESPN 2021


 
Systemic oxalate deposition in patients with primary hyperoxaluria type 3
CRISTINA MARTIN-HIGUERAS 1 MARK BORN 2 ULRIKE HERBERG 2 JOHANNES BIRTEL 2 BERND HOPPE 1

1- GERMAN HYPEROXALURIA CENTER
2- UNIVERSITY HOSPITAL BONN
 
Introduction:

Patients with Primary Hyperoxaluria type 3 (PH3) remain, in the contrary to previous reporting, symptomatic in adulthood with recurrent kidney stones. They are also on risk to develop chronic kidney disease (CKD). We therefore speculate, that PH3 patients may develop systemic oxalate deposition.

 

Material and methods:

We started to examine PH3 patients regularly seen at the German Hyperoxaluria Center (GHC) for systemic depositions by eye exam, hand x-rays, bone MRI (3 Tesla of the left knee and proximal tibia) and Speckle tracking echocardiography, which measures changes in global longitudinal strain (GLS), an index of left ventricular contractibility (normal GLS is ≤18%).

 

Results:

At GHC we see 12 pediatric and 4 adult patients on a regular basis, at least twice a year. All 16 patients are in no less than CKD 2. So far the following examinations were performed:

-        Eye in 8 patients, normal in all.

-        X-ray left hand in 6 patients, one patient (multiple stone removal procedures, decline in GFR) with tiny sclerosing areas at caput MCP IV and the thumb.

-        MRI of left knee and proximal tibia in 6 patients, textural changes in one.

-        Speckle tracking echocardiography in 8 patients, abnormal in one (GLS – 17.3 and left ventricular hypertrophy) and borderline in another (GLS – 18.6) in 2020. During 2021 GLS values returned to normal in both under increased treatment awareness (-23 and -21, respectively).

-        Two patients had salivary stones in the parotid gland, found in a routine x-ray of the jaw before orthodontic treatment.

Conclusions:

Although this is currently only data of a small cohort, systemic oxalate deposition may also occur in PH3. Of course, data in more patients are needed to elucidate the true risk of systemic oxalate deposition and we therefore recommend to screen all known PH3 patients.