Clinical characteristics, genetic profile and short-term outcomes of children with primary hyperoxaluria type 2: a nationwide experience

Background Three types of primary hyperoxaluria (PH) are recognized. However, data on PH type 2 (PH2), caused by defects in the GRHPR gene, are limited. Methods We reviewed the medical records of patients < 18 years of age with genetically-proven PH2 from seven centres across India to identify the age of onset, patterns of clinical presentation, short-term outcomes and genetic profile, and to determine if genotype–phenotype correlation exists. Results We report 20 patients (all with nephrolithiasis or nephrocalcinosis) diagnosed to have PH2 at a median (IQR) age of 21.5 (7, 60) months. Consanguinity and family history of kidney stones were elicited in nine (45%) and eight (40%) patients, respectively. The median (IQR) serum creatinine at PH2 diagnosis was 0.45 (0.29, 0.56) mg/dL with the corresponding estimated glomerular filtration rate being 83 (60, 96) mL/1.73 $ m^{2} $/min. A mutational hotspot (c.494 G > A), rare in Caucasians, was identified in 12 (60%) patients. An intronic splice site variant (c.735-1G > A) was noted in five (25%) patients. Four (20%) patients required surgical intervention for stone removal. Major adverse kidney events (mortality or chronic kidney disease (CKD) stages 3–5) were noted in six (30%) patients at a median (IQR) follow-up of 12 (6, 27) months. Risk factors for CKD progression and genotype–phenotype correlation could not be established. Conclusions PH2 should no longer be considered an innocuous disease, but rather a potentially aggressive disease with early age of presentation, and possible rapid progression to CKD stages 3–5 in childhood in some patients. A mutational hotspot (c.494 G > A variant) was identified in 60% of cases, but needs further exploration to decipher the genotype–phenotype correlation. Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:39

Enthalten in:

Pediatric nephrology - 39(2023), 4 vom: 02. Nov., Seite 1093-1104

Sprache:

Englisch

Beteiligte Personen:

Krishnasamy, Sudarsan [VerfasserIn]
Deepthi, Bobbity [VerfasserIn]
Kamath, Nivedita [VerfasserIn]
Iyengar, Arpana [VerfasserIn]
Thomas, Christy Cathreen [VerfasserIn]
Uthup, Susan [VerfasserIn]
Saha, Anshuman [VerfasserIn]
Mathew, Georgie [VerfasserIn]
Agarwal, Indira [VerfasserIn]
Tiewsoh, Karalanglin [VerfasserIn]
Bhat, Nowneet Kumar [VerfasserIn]
Mandal, Kausik [VerfasserIn]
Krishnamurthy, Sriram [VerfasserIn]

Links:

Volltext [lizenzpflichtig]

Themen:

C.494 g > a
C.735-1G > A
Nephrocalcinosis
Nephrolithiasis
Primary hyperoxaluria type 2

Anmerkungen:

© The Author(s), under exclusive licence to International Pediatric Nephrology Association 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

doi:

10.1007/s00467-023-06200-9

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

SPR054925541