Primary Hyperoxaluria Type 1: Diagnosis, and Treatment

Table 1. Organ involvement in PH patients with renal failure ^a
Organ	Symptoms	Diagnosis
Kidney^b	Stones, medullary or diffuse nephrocalcinosis, cortical nephrocalcinosis	US
Kidney^b		CT (cortical nephrocalcinosis may be missed on US)
Bone^c	Fractures, bone pain, growth retardation	X-ray: dense or lucent metaphyseal bands at the growth cartilage plate, vertebral condensations, osteopenia, epiphyseal nuclei (target-like) knee epiphyses
Eye^c	Disturbed vision, specific brown coloured retinal deposits	Fundoscopy
Arteries^d	Media calcifications	US, CT
Myocardium^d	Cardiac failure, arrhythmia, heart block, left ventricular hypertrophy, systolic and diastolic dysfunction	ECG, echocardiography
Myocardium^d		CT: calcifications
Thyroid^d	Hypothyroidism	US
Thyroid^d	Hypothyroidism	Thyroid function tests
Skin^e	(Painful) skin nodules, skin necrosis, gangrene, calciphylaxis-like skin lesions, pruritus	Skin biopsy
Nerves^e	Ischaemic neuropathy	Clinical assessment
Muscle^e	Myopathy by CaOx deposition	Biopsy, CT
Bowel^e	Prolonged oxalosis: depositions of CaOx in the intestinal wall	CT
Joints^e	Arthritis (late sign)	X-ray, CT

^aCT, computed tomography.
^bAlways involved.
^cFrequently involved.
^dOften involved.
^eLess often involved.

Table 2. Suggested transplantation options in pyridoxine-resistant PH1 patients according to residual GFR, systemic involvement and local facilities ^a
Tx options	Simultaneous liver + kidney	Sequential liver–kidney	Isolated kidney	Isolated liver
HD strategy	Peroperative ± postoperative according to POx and GFR	Standard HD following liver Tx aiming at POx < 20 μmol/L	Preoperative and peroperative	Sometimes peroperative
CKD Stage 3 (30 < GFR < 59)	No	No	No	Option in carefully selected patients
CKD Stage 4 (15 < GFR < 29)	Yes	Option	Option if B6 response but no evidence	No
CKD Stage 5 (GFR < 15)	Yes	Yes	Option if B6 response but no evidence	No
Infantile form (ESRD < 2 years)	Yes	Yes	No	No

^aPOx, plasma oxalate; Tx, transplantation.

Authors and Disclosures

Pierre Cochat¹, Sally-Anne Hulton², Cécile Acquaviva³, Christopher J. Danpure⁴, Michel Daudon⁵, Mario De Marchi⁶, Sonia Fargue⁴, Jaap Groothoff⁷, Jérôme Harambat⁸, Bernd Hoppe⁹, Neville V. Jamieson¹⁰, Markus J. Kemper¹¹, Giorgia Mandrile⁶, Martino Marangella¹², Stefano Picca¹³, Gill Rumsby¹⁴, Eduardo Salido¹⁵, Michael Straub¹⁶ and Christiaan S. van Woerden⁷; on behalf of OxalEurope (https://www.oxaleurope.com/)

¹Reference Center for Rare Renal Diseases & EPICIME, Department of Paediatrics, Hospices Civils de Lyon and Université Claude-Bernard Lyon 1, Lyon, France, ²Department of Nephrology, Birmingham Children's Hospital NHS Trust, Birmingham, UK, ³Laboratory of Inborn Metabolic Diseases, Centre de Biologie Est, Hospices Civils de Lyon, Lyon, France, ⁴Division of Biosciences, Department of Cell and Developmental Biology, University College London, London, UK, ⁵Department of Functional Investigations, Laboratory of Urolithiasis, Tenon Hospital, Paris, France, ⁶Medical Genetics Unit, University of Torino, San Luigi Hospital, Torino, Italy, ⁷Department of Paediatric Nephrology, Emma Children's Hospital, Academic Medical Centre, Amsterdam, The Netherlands, ⁸Department of Pediatrics, Bordeaux University Hospital, Bordeaux, France, ⁹Division of Pediatric Nephrology, Department of Pediatric and Adolescent Medicine, University Hospital Cologne, Cologne, Germany, ¹⁰Department of Surgery, Cambridge University Hospitals, Cambridge, UK, ¹¹Department of Pediatric Nephrology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, ¹²Nephrology and Dialysis Unit, Mauriziano Hospital, Turin, Italy, ¹³Dialysis Unit, Department of Nephrology-Urology, Bambino Gesù Children's Research Hospital, Rome, Italy, ¹⁴Clinical Biochemistry, UCL Hospitals, London, UK, ¹⁵Centre for Biomedical Research on Rare Diseases (CIBERER) Hospital Universitario Canarias, University of La Laguna, Tenerife, Spain and ¹⁶Rechts der Isar Medical Center, Department of Urology, Technische Universität München, München, Germany

Conflict of interest statement
None declared.

Correspondence and offprint requests to
Pierre Cochat; E-mail: pierre.cochat@chu-lyon.fr