Adenine Phosphoribosyltransferase Deficiency Presenting with Supposed ‘Uric Acid’ Stones: Pitfalls of Diagnosis1

Background: Kidney stones are one of the oldest known and common diseases in the urinary tract with a prevalence that varies from 1% to 20%. Many phytotherapic and herbal medicines for kidney stones have been described for their treatment and prevention. Objective: The objective of this study is to perform a comprehensive review of several phytotherapic and herbal medicines published including clinical and animal studies. Results: Phytotherapy may influence the risk of recurrence in calcium oxalate and uric acid stones. The most solid evidence suggest that Phyllanthus niruri is one of the most studied components that appear to interfere with the calcium oxalate crystallization, reduced hyperoxaluria and hiperuricosuria and increased shock wave lithotripsy efficacy due to reduced crystallization without significant adverse effects, also Theobromine have shown to reduce the crystallization of uric acid in patients and appears to be a promising supplement to treat such stones. Conclusion: Many phytoterapic and herbal agents have been studies to treat and present urolithiasis, most of them only with studies of small number of patients or in animal models. Further randomized clinical trials are needed to evaluate the effect of these agents in kidney stones.

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Incidence and Characteristics of Kidney Stones in Patients on Ketogenic Diet: A Systematic Review and Meta-Analysis

Diseases ◽

10.3390/diseases9020039 ◽

2021 ◽

Vol 9 (2) ◽

pp. 39

Author(s):

Prakrati Acharya ◽

Chirag Acharya ◽

Charat Thongprayoon ◽

Panupong Hansrivijit ◽

Swetha R. Kanduri ◽

...

Keyword(s):

Uric Acid ◽

Kidney Stones ◽

Observational Studies ◽

Meta Analysis ◽

Random Effects Model ◽

Ketogenic Diets ◽

Cochrane Database ◽

Uric Acid Stones ◽

Low Carbohydrate

Very-low-carbohydrate diets or ketogenic diets are frequently used for weight loss in adults and as a therapy for epilepsy in children. The incidence and characteristics of kidney stones in patients on ketogenic diets are not well studied. Methods: A systematic literature search was performed, using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from the databases’ inception through April 2020. Observational studies or clinical trials that provide data on the incidence and/or types of kidney stones in patients on ketogenic diets were included. We applied a random-effects model to estimate the incidence of kidney stones. Results: A total of 36 studies with 2795 patients on ketogenic diets were enrolled. The estimated pooled incidence of kidney stones was 5.9% (95% CI, 4.6–7.6%, I2 = 47%) in patients on ketogenic diets at a mean follow-up time of 3.7 +/− 2.9 years. Subgroup analyses demonstrated the estimated pooled incidence of kidney stones of 5.8% (95% CI, 4.4–7.5%, I2 = 49%) in children and 7.9% (95% CI, 2.8–20.1%, I2 = 29%) in adults, respectively. Within reported studies, 48.7% (95% CI, 33.2–64.6%) of kidney stones were uric stones, 36.5% (95% CI, 10.6–73.6%) were calcium-based (CaOx/CaP) stones, and 27.8% (95% CI, 12.1–51.9%) were mixed uric acid and calcium-based stones, respectively. Conclusions: The estimated incidence of kidney stones in patients on ketogenic diets is 5.9%. Its incidence is approximately 5.8% in children and 7.9% in adults. Uric acid stones are the most prevalent kidney stones in patients on ketogenic diets followed by calcium-based stones. These findings may impact the prevention and clinical management of kidney stones in patients on ketogenic diets.

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Allele frequency of variants reported to cause adenine phosphoribosyltransferase deficiency

European Journal of Human Genetics ◽

10.1038/s41431-020-00805-6 ◽

2021 ◽

Author(s):

Hrafnhildur L. Runolfsdottir ◽

John A. Sayer ◽

Olafur S. Indridason ◽

Vidar O. Edvardsson ◽

Brynjar O. Jensson ◽

...

Keyword(s):

Allele Frequency ◽

Autosomal Recessive Disorder ◽

European Population ◽

Adenine Phosphoribosyltransferase ◽

Genomic Databases ◽

Pathogenic Variants ◽

Adenine Phosphoribosyltransferase Deficiency ◽

Variation Database ◽

The Uk ◽

Aprt Deficiency

AbstractAdenine phosphoribosyltransferase deficiency is a rare, autosomal recessive disorder of purine metabolism that causes nephrolithiasis and progressive chronic kidney disease. The small number of reported cases indicates an extremely low prevalence, although it has been suggested that missed diagnoses may play a role. We assessed the prevalence of APRT deficiency based on the frequency of causally-related APRT sequence variants in a diverse set of large genomic databases. A thorough search was carried out for all APRT variants that have been confirmed as pathogenic under recessive mode of inheritance, and the frequency of the identified variants examined in six population genomic databases: the deCODE genetics database, the UK Biobank, the 100,000 Genomes Project, the Genome Aggregation Database, the Human Genetic Variation Database and the Korean Variant Archive. The estimated frequency of homozygous genotypes was calculated using the Hardy-Weinberg equation. Sixty-two pathogenic APRT variants were identified, including six novel variants. Most common were the missense variants c.407T>C (p.(Met136Thr)) in Japan and c.194A>T (p.(Asp65Val)) in Iceland, as well as the splice-site variant c.400 + 2dup (p.(Ala108Glufs*3)) in the European population. Twenty-nine variants were detected in at least one of the six genomic databases. The highest cumulative minor allele frequency (cMAF) of pathogenic variants outside of Japan and Iceland was observed in the Irish population (0.2%), though no APRT deficiency cases have been reported in Ireland. The large number of cases in Japan and Iceland is consistent with a founder effect in these populations. There is no evidence for widespread underdiagnosis based on the current analysis.

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