-
Drugs Dec 2023Nedosiran (RIVFLOZA™), a once-monthly subcutaneous small interfering RNA (siRNA) therapy, is being developed by Dicerna Pharmaceuticals, a Novo Nordisk company, for... (Review)
Review
Nedosiran (RIVFLOZA™), a once-monthly subcutaneous small interfering RNA (siRNA) therapy, is being developed by Dicerna Pharmaceuticals, a Novo Nordisk company, for the treatment of primary hyperoxaluria (PH). It reduces oxalate overproduction by inhibiting the expression of the hepatic lactate dehydrogenase (LDH) enzyme. Nedosiran received its first approval on 29 September 2023 in the USA to lower urinary oxalate levels in children aged ≥ 9 years and adults with PH type 1 (PH1) and relatively preserved kidney function [e.g. estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73 m]. This article summarizes the milestones in the development of nedosiran leading to this first approval for PH1.
Topics: Child; Adult; Humans; Hyperoxaluria, Primary; Oxalates; Lactate Dehydrogenases; RNA, Small Interfering
PubMed: 38060091
DOI: 10.1007/s40265-023-01976-4 -
Pediatric Transplantation Feb 2024Combined liver-kidney transplantation (CLKT) is a surgical procedure that involves transplanting both liver and kidney organs. There are two types of CLKT: simultaneous... (Review)
Review
Combined liver-kidney transplantation (CLKT) is a surgical procedure that involves transplanting both liver and kidney organs. There are two types of CLKT: simultaneous liver-kidney transplantation (smLKT) and sequential LKT (sqLKT). CLKT accounts for a small percentage of liver transplantations (LTs), particularly in pediatric cases. Nevertheless, the procedure has demonstrated excellent outcomes, with high survival rates and lower rejection rates. The main indications for CLKT in pediatric patients differ somewhat from that in adults, in which end-stage kidney disease after LT is the major indication. In children, congenital diseases are common reason for performing CLKT; the examples of such diseases include autosomal recessive polycystic kidney disease with congenital hepatic fibrosis which equally affects both organs, and primary hyperoxaluria type 1, a primary liver disease leading kidney failure. The decision between smLKT or sqLKT depends on the dominant organ failure, the specific pathophysiology, and available organ sources. However, there remain significant surgical and societal challenges surrounding CLKT. Innovations in pharmacology and genetic engineering have decreased the necessity for CLKT in early-diagnosed cases without portal hypertension or kidney replacement therapy. Nonetheless, these advancements are not universally accessible. Therefore, decision-making algorithms should be crafted, considering region-specific organ allocation systems and prevailing medical environments.
Topics: Adult; Child; Humans; Kidney Transplantation; Liver Transplantation; Treatment Outcome; Kidney Diseases; Liver Failure; Hypertension, Portal; Kidney
PubMed: 38059323
DOI: 10.1111/petr.14666 -
Retinal Cases & Brief Reports Dec 2023To report the case of severe bilateral retinal vascular occlusion in a patient with hyperoxalosis and chronic renal failure.
PURPOSE
To report the case of severe bilateral retinal vascular occlusion in a patient with hyperoxalosis and chronic renal failure.
METHODS
Observational case report. Medical and imaging records were retrospectively reviewed. The patient was imaged with ultra-widefield (UWF) fundus photography and fluorescein angiography (UWF-FA), cross sectional and en face spectral-domain optical coherence tomography (SD-OCT), and OCT angiography.
RESULTS
A 32-year-old diabetic patient receiving peritoneal dialysis was referred because of severe vision loss. UWF color fundus photography showed diffuse sclerotic retinal vessels and diffuse intraretinal crystals in both eyes. UWF-FA illustrated near-complete retinal vascular occlusion and capillary wipe out in both eyes. SD-OCT demonstrated diffuse inner and middle retina thinning in both eyes and multiple intraretinal hyperreflective foci consistent with crystalline deposits in all retina layers of both eyes. OCT angiography revealed severe capillary and large vessel non-perfusion in the superficial and deep retinal capillary plexus of each eye. The serum oxalate levels were increased at 28 µmol/L (reference range < 2 µmol/L) and genetic testing was positive for a heterozygous mutation of the AGXT (Alanine-Glyoxylate Amino Transferase) gene that causes type 1 autosomal recessive primary hyperoxaluria.
CONCLUSION
A diagnosis of hyperoxalosis causing severe retinal vascular occlusion was rendered. Hyperoxalosis was the result of multiple factors including heterozygous AGXT mutation, chronic renal failure insufficiently treated with peritoneal dialysis, and a diet high in oxalate. This case highlights the importance of ruling out retinal oxalosis in patients on peritoneal dialysis in order to initiate prompt hemodialysis and prevent severe retinal vascular occlusion.
PubMed: 38055904
DOI: 10.1097/ICB.0000000000001519 -
Kidney International Reports Nov 2023
PubMed: 38025235
DOI: 10.1016/j.ekir.2023.09.012 -
Rhode Island Medical Journal (2013) Dec 2023Hyperoxaluria is a clinically relevant metabolic entity that portends a high morbidity burden. Primarily manifesting as kidney stone disease and chronic kidney disease,... (Review)
Review
Hyperoxaluria is a clinically relevant metabolic entity that portends a high morbidity burden. Primarily manifesting as kidney stone disease and chronic kidney disease, advanced hyperoxaluria can also affect major organs, including the brain, heart, liver, bone, and the skin. It is categorized based on etiology into primary and secondary hyperoxaluria. Pathology is attributed to excess de novo oxalate production in the former and multifactorial exogenous oxalate absorption or excess intake of its precursors in the latter. Diagnosis often involves demonstrating elevated urinary oxalate levels, especially in patients with normal kidney function. Here in this review, we will perform an in-depth discussion of various causes of hyperoxaluria and describe treatment options. In view of the significant morbidity burden associated with hyperoxaluria, patients could benefit from heightened clinician awareness to aid in the timely diagnosis and management of this condition.
Topics: Humans; Kidney Calculi; Hyperoxaluria; Oxalates
PubMed: 38015779
DOI: No ID Found -
Cureus Oct 2023Primary hyperoxaluria-1 (PH1) is an autosomal recessively inherited rare genetic condition due to the deficiency of the hepatic enzyme alanine:glyoxylate...
Primary hyperoxaluria-1 (PH1) is an autosomal recessively inherited rare genetic condition due to the deficiency of the hepatic enzyme alanine:glyoxylate aminotransferase which leads to high systemic levels of oxalate and subsequently, early end-stage renal disease and death. Here, we present a case of a three-month-old male infant who presented with loose stools, reduced oral intake, and decreased activity for 12-13 days along with edema and a peeling rash on cheeks, lips, and genitalia. During the entire duration of the inpatient stay, the child was oligoanuric. Kidney ultrasound (USG) was suggestive of bilateral hyperechoic kidneys with increased cortical echogenicity and a computed tomography scan showed bilateral diffusely calcified renal cortices with well-preserved renal architecture. A diagnosis of "oxalate nephropathy" was made from renal biopsy and genetic testing confirmed it to be "primary hyperoxaluria-1". The child was initially managed conservatively, and then peritoneal dialysis was done, following which the child was shifted to intermittent hemodialysis.
PubMed: 37954792
DOI: 10.7759/cureus.46827 -
Cureus Oct 2023Primary hyperoxaluria type 2 (PH2) is a rare genetic disorder characterized by excessive oxalate production due to glyoxylate metabolism alterations. This case report...
Primary hyperoxaluria type 2 (PH2) is a rare genetic disorder characterized by excessive oxalate production due to glyoxylate metabolism alterations. This case report presents a 26-year-old male with PH2 who experienced recurrent nephrolithiasis since childhood, leading to end-stage renal disease (ESRD). The patient's history prompted genetic testing, which revealed a heterozygous missense variant in the gene, confirming PH2. Early genetic diagnosis is crucial for preventing ESRD and planning effective treatments. Patients with PH2 require intensive hemodialysis and may benefit from kidney transplantation. However, even after transplantation, ongoing preventive measures are essential due to the risk of hyperoxaluria-related graft damage. This case highlights the importance of early detection and genetic testing in managing PH2 to delay ESRD and improve patient outcomes.
PubMed: 37933374
DOI: 10.7759/cureus.46555 -
Progres En Urologie : Journal de... Nov 2023The morphological-compositional analysis of urinary stones allows distinguishing schematically several situations: dietary, digestive, metabolic/hormonal, infectious and... (Review)
Review
The morphological-compositional analysis of urinary stones allows distinguishing schematically several situations: dietary, digestive, metabolic/hormonal, infectious and genetic problems. Blood and urine testing are recommended in the first instance to identify risk factors of urinary stone disease in order to avoid recurrence or progression. The other objective is to detect a potential underlying pathology associated with high risk of urinary stone disease (e.g. primary hyperparathyroidism, primary or enteric hyperoxaluria, cystinuria, distal renal tubular acidosis) that may require specific management. Lifestyle-diet measures are the basis of the management of all stone types, but pharmacological treatments may be required. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU 2022] and their adaptability to the French context.
Topics: Humans; Lithiasis; Urolithiasis; Urinary Calculi; Urology; Risk Factors
PubMed: 37918992
DOI: 10.1016/j.purol.2023.08.004 -
Pediatric Nephrology (Berlin, Germany) Apr 2024Three types of primary hyperoxaluria (PH) are recognized. However, data on PH type 2 (PH2), caused by defects in the GRHPR gene, are limited. (Review)
Review
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/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.
Topics: Child; Humans; Infant; Genetic Profile; Hyperoxaluria, Primary; Nephrolithiasis; Renal Insufficiency, Chronic
PubMed: 37914965
DOI: 10.1007/s00467-023-06200-9 -
Annals of Laboratory Medicine May 2024Plasma oxalate measurements can be used for the screening and therapeutic monitoring of primary hyperoxaluria. We developed a gas chromatography-mass spectrometry...
BACKGROUND
Plasma oxalate measurements can be used for the screening and therapeutic monitoring of primary hyperoxaluria. We developed a gas chromatography-mass spectrometry (GC-MS) assay for plasma oxalate measurements with high sensitivity and suitable testing volumes for pediatric populations.
METHODS
Plasma oxalate was extracted, derivatized, and analyzed by GC-MS. We measured the ion at m/z 261.10 to quantify oxalate and the C-oxalate ion (m/z: 263.15) as the internal standard. Method validation included determination of the linear range, limit of blank, limit of detection, lower limit of quantification, precision, recovery, carryover, interference, and dilution effect. The cut-off value between primary and non-primary hyperoxaluria in a pediatric population was analyzed.
RESULTS
The detection limit was 0.78 μmol/L, and the linear range was up to 80.0 μmol/L. The between-day precision was 5.7% at 41.3 μmol/L and 13.1% at 1.6 μmol/L. The carryover was <0.2%. The recovery rate ranged from 90% to 110%. Interference analysis showed that Hb did not interfere with plasma oxalate quantification, whereas intralipids and bilirubin caused false elevation of oxalate concentrations. A cut-off of 13.9 μmol/L showed 63% specificity and 77% sensitivity, whereas a cut-off of 4.15 μmol/L showed 100% specificity and 20% sensitivity. The minimum required sample volume was 250 μL. The detected oxalate concentrations showed interference from instrument conditioning, sample preparation procedures, medications, and various clinical conditions.
CONCLUSIONS
GC-MS is a sensitive assay for quantifying plasma oxalate and is suitable for pediatric patients. Plasma oxalate concentrations should be interpreted in a clinical context.
Topics: Humans; Child; Gas Chromatography-Mass Spectrometry; Oxalates; Hyperoxaluria, Primary
PubMed: 37904578
DOI: 10.3343/alm.2023.0178