Characteristic clinical and biochemical profile of recurrent calcium-oxalate nephrolithiasis in patients with metabolic syndrome

Imiglucerase, cholecalciferol, and bone-diet in skeletal health management of type I Gaucher disease patients: a pilot study and systematic review

Skeletal anomalies represent a characteristic feature of type 1 Gaucher disease (GD1). Here we evaluated the impact of an integrated therapy comprising enzyme-replacement therapy (ERT), cholecalciferol, and a normocalcemic-normocaloric-hyposodic diet (bone diet) on bone health in GD1 patients. We also performed a systematic review to compare our results with available data. From January 1, 2015 to February 28, 2019, all GD1 patients referred to Federico II University were enrolled and treated with the integrated therapy. Bone turnover markers and bone mineral density (BMD) were evaluated at baseline (T0) and after 24 months (T24). We enrolled 25 GD1 patients, all showing 25-hydroxy vitamin D (25OHD) levels < 50 nmol/l (hypovitaminosis D) at T0. Response to cholecalciferol treatment was effective, showing a direct relationship between 25OHD levels before and after treatment. At T0, 2 GD1 patients showed fragility fractures, 5 the Erlenmeyer flask deformity, 3 osteonecrosis, and 7 a BMD Z-score ≤ -2. Overall, GD1 patients with bone anomalies showed higher C-terminal telopeptide levels compared with those without bone anomalies. No new bone anomalies occurred during 2 years of follow-up. At T24, BMD remained stable across the entire study cohort, including in patients with bone anomalies. The systematic review showed that our study is the first that evaluated all bone health parameters. Hypovitaminosis D is prevalent in GD1 patients. The response to cholecalciferol treatment was effective but different to healthy subjects and in patients with metabolic bone disorders. Integrated therapy including ERT, cholecalciferol, and bone diet guarantees bone health.

Idiopathic Osteoporosis and Nephrolithiasis: Two Sides of the Same Coin?

Idiopathic osteoporosis and nephrolithiasis are formidable health problems showing a progressive increase in their incidence and prevalence in the last decades. These temporal trends were observed in both pediatric and adult populations worldwide. Epidemiological and experimental studies indicate that both disorders show several common pathogenic environmental and genetic factors. In this review, we analyzed the clinical characteristics common to the two disorders and the state-of-the-art knowledge regarding the genetic predisposition and the environmental factors recognized as triggers in adult and pediatric ages. As a result of this work, we propose to consider idiopathic nephrolithiasis and osteoporosis as two possible expressions of a unique clinical syndrome. Accordingly, the clinical approach to both disorders should be modified in order to program an efficient primary and secondary prevention strategy.

The association between a non-invasive hepatic fibrosis score and urolithiasis among non-alcoholic fatty liver disease (NAFLD) patients in China: a cross-sectional study

OBJECTIVE

Mounting data now support a strong link between the presence of non-alcoholic fatty liver disease (NAFLD) and an increased risk of urolithiasis. However, little is known on the association between hepatic fibrosis and the risk of urolithiasis among NAFLD patients. Therefore, this study aimed to investigate the prevalence of urolithiasis among NAFLD patients and determine whether the Fibrosis-4 (FIB-4) score, a surrogate marker of hepatic fibrosis, is associated with urolithiasis among NAFLD patients.

DESIGN

Cross-sectional studies.

SETTING

China.

METHODS

A total of 2058 adult patients with NAFLD were included in this study. Logistic regression analysis was used to detect the association between FIB-4 score and urolithiasis. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic value of FIB-4 score for the detection of urolithiasis among NAFLD patients.

RESULTS

200 (9.7%) individuals had ultrasonography-diagnosed urolithiasis among 2058 NAFLD patients. FIB-4 score (OR=1.58; 95% CI 1.06 to 2.31), age (OR=1.11; 95% CI 1.08 to 1.13), obesity (OR=3.16; 95% CI 2.29 to 4.39) and hyperuricemia (OR=3.79; 95% CI 2.67 to 5.36) were independent factors associated with urolithiasis among NAFLD patients. Moreover, a novel algorithm including multiple variables (FIB-4 score, age, obesity and hyperuricemia) showed an area under a ROC curve of 0.813 (95% CI 0.795 to 0.829) for identifying urolithiasis among NAFLD patients. The optimal cut-off value of > -2.23 for the multivariate model provides a sensitivity of 76% and a specificity of 74% for predicting urolithiasis among NAFLD patients.

CONCLUSION

Urolithiasis among NAFLD patients is associated with FIB-4 score. Further, a novel algorithm based on FIB-4 score could serve as a useful tool for identifying individuals with a higher risk of urolithiasis among NAFLD patients, although prospective cohort studies are still needed in the future.

Dietary vinegar prevents kidney stone recurrence via epigenetic regulations

BACKGROUND

Epidemiological evidence of over 9000 people suggests that daily intake of vinegar whose principal bioactive component is acetic acid is associated with a reduced risk of nephrolithiasis. The underlying mechanism, however, remains largely unknown.

METHODS

We examined the in vitro and in vivo anti-nephrolithiasis effects of vinegar and acetate. A randomized study was performed to confirm the effects of vinegar in humans.

FINDINGS

We found individuals with daily consumption of vinegar compared to those without have a higher citrate and a lower calcium excretion in urine, two critical molecules for calcium oxalate (CaOx) kidney stone in humans. We observed that oral administration of vinegar or 5% acetate increased citrate and reduced calcium in urinary excretion, and finally suppressed renal CaOx crystal formation in a rat model. Mechanism dissection suggested that acetate enhanced acetylation of Histone H3 in renal tubular cells and promoted expression of microRNAs-130a-3p, -148b-3p and -374b-5p by increasing H3K9, H3K27 acetylation at their promoter regions. These miRNAs can suppress the expression of Nadc1 and Cldn14, thus enhancing urinary citrate excretion and reducing urinary calcium excretion. Significantly these mechanistic findings were confirmed in human kidney tissues, suggesting similar mechanistic relationships exist in humans. Results from a pilot clinical study indicated that daily intake of vinegar reduced stone recurrence, increased citrate and reduced calcium in urinary excretion in CaOx stone formers without adverse side effects.

INTERPRETATION

Vinegar prevents renal CaOx crystal formation through influencing urinary citrate and calcium excretion via epigenetic regulations. Vinegar consumption is a promising strategy to prevent CaOx nephrolithiasis occurrence and recurrence. FUND: National Natural Science Foundations of China and National Natural Science Foundation of Guangdong Province.

The severity of NAFLD is associated with the risk of urolithiasis

BACKGROUND AND AIMS

Population-based studies suggest a strong association between the presence of nonalcoholic fatty liver disease (NAFLD) and an increased risk of urolithiasis. However, the available information on the association of the severity of NAFLD with urolithiasis is limited. We hypothesised a link between the severity of NAFLD and the risk of urolithiasis.

METHODS

We recruited 1527 adult patients with NAFLD who completed a comprehensive health checkup. The severity of NAFLD was measured with AST to platelet ratio (APRI score). Logistic regression analysis was used to detect the association of APRI score with the risk of urolithiasis among NAFLD patients. ROC analysis was used to assess the diagnostic value of APRI score for identifying urolithiasis among NAFLD patients.

RESULTS

Multivariate analysis showed three independent risk factors for urolithiasis: obesity (OR 2.06 95%CI 1.35-3.13), APRI score (OR 1.29 95%CI 1.05-1.59), and serum uric acid (OR 1.07 95%CI 1.05-1.09), suggesting an independent association between the noninvasive staging of liver fibrosis and the risk of urolithiasis in NAFLD patients. A three-variable model (obesity, APRI score, and serum uric acid) with an AUROC of 0.73 (95% CI 0.70-0.75) was significant in identifying urolithiasis.

CONCLUSIONS

The severity of NAFLD is associated with the risk of urolithiasis among NAFLD patients. Moreover, a three-variable model (obesity, APRI score, serum uric acid) could serve as a useful tool for identifying individuals at high risk for urolithiasis in these patients.

Metabolic syndrome and nephrolithiasis: a systematic review and meta-analysis of the scientific evidence

The metabolic syndrome is a cluster of cardiometabolic alterations at least partly dependent on reduced insulin sensitivity and hyperinsulinemia that can have several renal implications. A systematic review and meta-analysis of studies available in the international literature in English language demonstrates that the metabolic syndrome occurrence is associated with a significantly higher prevalence of nephrolithiasis (odds ratio 1.29, 95% confidence intervals: 1.11-1.51). The pathophysiological bases of this association are currently not completely understood, however. Potential pathogenetic links between the two conditions include metabolic factors that promote insulin resistance as well as stone formation in urine, environmental factors such as diet, oxidative stress and inflammation, and molecular changes impacting the transport of some analytes in urine. Metabolic syndrome-related nephrolithiasis shows peculiar clinical and biochemical characteristics and should be considered a multifactorial systemic disorder needing a multidisciplinary approach for adequate prevention and management in pediatric and adult age.

Urinary calcium excretion and insulin resistance in patients with acromegaly

BACKGROUND

Renal complications in acromegaly include glomerular hyperfiltration, insulin resistance, hypercalciuria and urolithiasis. The aim of this study was to investigate whether urinary calcium (U(Ca)) excretion is a direct consequence of growth hormone secretion or secondary to hyperfiltration and/or insulin resistance.

METHODS

We performed a cross-sectional study of 58 patients diagnosed with acromegaly. Demographic data were obtained, serum analysis was performed, including insulin-like growth factor (IGF)-1, and 24-h urine collection, to measure urinary protein excretion, U(Ca) and phosphate excretion, as well as fractional excretion of sodium and potassium. We also calculated the homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

Patients were predominantly male (60.3%), and their mean age was 45.9 ± 14 years. Hypercalciuria was present in 24% of patients. Patients with higher HOMA-IR had higher IGF-1 levels, a trend toward higher body mass index and higher U(Ca) excretion. In univariate analysis, U(Ca) excretion was associated with HOMA-IR (r = 0.472, P = 0.001), phosphaturia (r = 0.457, P = 0.001), IGF-1 (r = 0.398, P = 0.002) and creatinine clearance (r = 0.394, P = 0.001). HOMA-IR and phosphaturia were independently associated with U(Ca) excretion. No independent associations were found between phosphaturia and HOMA-IR or IGF-1.

CONCLUSIONS

The present study revealed an association between hypercalciuria and insulin resistance in patients with acromegaly. Further studies are required to fully understand the pathogenesis of these abnormalities in patients with acromegaly.

The melatonin receptor 1A (MTNR1A) gene is associated with recurrent and idiopathic calcium nephrolithiasis

BACKGROUND

Experimental evidence indicate that melatonin regulates some renal tubular functions via specific melatonin receptors (MTNRs) located in the kidney of several avian and mammalian species, including humans. We hypothesized that single nucleotide polymorphisms (SNPs) in the melatonin receptor 1A gene (MTNR1A) might influence the risk of calcium nephrolithiasis.

METHODS

We performed a systematic analysis of the MTNR1A gene in 246 recurrent calcium stone formers (136 men, 110 women; mean age 40.2 ± 12.0 years; body mass index 25.8 ± 4.5 kg/m2) and 269 healthy controls comparable for age and gender without a history of nephrolithiasis.

RESULTS

Two SNPs in Intron 1 of MTNR1A were significantly associated with calcium nephrolithiasis: rs13140012 (P = 0.0004) and rs6553010 (P = 0.009). The haplotypes resulting from the two SNPs were also differently distributed between stone formers and controls, the haplotype A-T being more represented among stone formers (P = 0.00001) and the haplotype T-C being more common in healthy controls (P = 0.00001). Preliminary functional studies showed that the SNP rs13140012 could modify the binding sites for transcription factors.

CONCLUSION

The results of this case-control study indicate a strong association between allelic variants of MTNR1A and recurrent calcium nephrolithiasis.