Association Between Urinary Protein-to-Creatinine Ratio and Chronic Kidney Disease Progression: A Secondary Analysis of a Prospective Cohort Study

Pre-clinical evaluation of biomarkers for the early detection of nephrotoxicity following alpha-particle radioligand therapy

PURPOSE

Cancer treatment with alpha-emitter-based radioligand therapies (α-RLTs) demonstrates promising tumor responses. Radiolabeled peptides are filtered through glomeruli, followed by potential reabsorption of a fraction by proximal tubules, which may cause acute kidney injury (AKI) and chronic kidney disease (CKD). Because tubular cells are considered the primary site of radiopeptides' renal reabsorption and potential injury, the current use of kidney biomarkers of glomerular functional loss limits the evaluation of possible nephrotoxicity and its early detection. This study aimed to investigate whether urinary secretion of tubular injury biomarkers could be used as an additional non-invasive sensitive diagnostic tool to identify unrecognizable tubular damage and risk of long-term α-RLT nephrotoxicity.

METHODS

A bifunctional cyclic peptide, melanocortin 1 ligand (MC1L), labeled with [203Pb]Pb-MC1L, was used for [212Pb]Pb-MC1L biodistribution and absorbed dose measurements in CD-1 Elite mice. Mice were treated with [212Pb]Pb-MC1L in a dose-escalation study up to levels of radioactivity intended to induce kidney injury. The approach enabled prospective kidney functional and injury biomarker evaluation and late kidney histological analysis to validate these biomarkers.

RESULTS

Biodistribution analysis identified [212Pb]Pb-MC1L reabsorption in kidneys with a dose deposition of 2.8, 8.9, and 20 Gy for 0.9, 3.0, and 6.7 MBq injected [212Pb]Pb-MC1L doses, respectively. As expected, mice receiving 6.7 MBq had significant weight loss and CKD evidence based on serum creatinine, cystatin C, and kidney histological alterations 28 weeks after treatment. A dose-dependent urinary neutrophil gelatinase-associated lipocalin (NGAL, tubular injury biomarker) urinary excretion the day after [212Pb]Pb-MC1L treatment highly correlated with the severity of late tubulointerstitial injury and histological findings.

CONCLUSION

Urine NGAL secretion could be a potential early diagnostic tool to identify unrecognized tubular damage and predict long-term α-RLT-related nephrotoxicity.

Carotid intima media thickness as a marker of increased cardiovascular risk due to androgenic anabolic steroids in male bodybuilders: a cross-sectional study

BACKGROUND

The usage of androgenic-anabolic steroids (AAS) leads to severe side effects. The aim of our study was to investigate the effects of AAS on the increase in the carotid intima-media thickness which is regarded as predictor of cardiovascular disorders and determine the association of ASS usage to urinary, hepatic, and hematological systems as well as lipid disorders.

METHODS

A total of 60 male bodybuilders (30 AAS users with a mean age of 31.2±8.9 years and 30 AAS nonusers with a mean age of 31.2±8.9 years) were assessed in this cross-sectional study. The patients' demographic, radiologic, hormonal, and biochemical parameters were recorded. The carotid intima-media thickness (CIMT) was measured using B-mode ultrasound in both groups. Abdominal ultrasonography was used to assess for the presence of fatty liver.

RESULTS

CIMT was significantly increased in AAS (0.72±0.13 mm) users than in the controls (0.47±0.07 mm) (P<0.001). The mean duration of AAS usage was 2.70±2.13 years. There was a statistically significant positive correlation between the duration of AAS usage and CIMT (r=0.710; P<0.001). A statistically significant negative correlation among HDL, LH, and CIMT was found in the correlation analysis between biochemical parameters and CIMT among AAS users (respectively, r and P values were: r=0.399; P=0.029; r=-0.366; P=0.047; r=-0.287; P=0.035). Likewise, a negative correlation (r=-0.425; P=0.019) was found between FSH and CIMT.

CONCLUSIONS

We found that the usage of AAS among male bodybuilders has led to an increase in CIMT, which is associated with poor cardiovascular health. The results of our study highlight the vital importance of educating male bodybuilders who use these chemicals about the side effects.

Efficacy of Voclosporin in Proliferative Lupus Nephritis with High Levels of Proteinuria

BACKGROUND

In a phase 3 study of adults with active lupus nephritis, addition of voclosporin to mycophenolate mofetil (MMF) and low-dose glucocorticoids led to significant improvements in the proportion of participants achieving complete and partial renal response as well as sustained reduction in proteinuria. This analysis examined the efficacy and safety of voclosporin in a subgroup of the phase 3 study with proliferative lupus nephritis and high levels of proteinuria.

METHODS

Participants were randomized to oral voclosporin (23.7 mg twice daily) or placebo for 12 months; all participants received MMF and low-dose glucocorticoids. This analysis includes participants with class III or IV (±class V) lupus nephritis and baseline urine protein-creatinine ratio (UPCR) ≥3 g/g. Efficacy end points included complete renal response (UPCR ≤0.5 g/g with stable eGFR, low-dose glucocorticoids, and no rescue medication), partial renal response (≥50% reduction from baseline UPCR), and UPCR over time. Safety outcomes were also assessed.

RESULTS

A total of 148 participants were in the voclosporin ( n =76) and control ( n =72) arms. At 12 months, 34% and 11% of participants in the voclosporin and control arms, respectively, achieved a complete renal response (odds ratio, 4.43; 95% confidence interval [CI], 1.78 to >9.99; P = 0.001). A partial renal response was achieved by 65% of the voclosporin arm and 51% of the control arm at 12 months (odds ratio, 1.60; 95% CI, 0.8 to 3.20; P = 0.18). More voclosporin- than control-treated participants achieved UPCR ≤0.5 g/g (51% versus 26%), and voclosporin-treated participants met this end point significantly earlier (hazard ratio, 2.07; 95% CI, 1.19 to 3.60; P = 0.01). The incidence of adverse events was similar between the arms; mean eGFR values remained stable and within normal range in both arms.

CONCLUSIONS

Addition of voclosporin to MMF and low-dose glucocorticoids resulted in a significantly higher proportion of participants with proliferative lupus nephritis achieving complete and partial renal responses as well as earlier reductions in proteinuria, with no evidence of worsening kidney function.

Renal improvement and remission in a patient with refractory ANCA-associated vasculitis treated with avacopan

Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis is associated with end-organ damage resulting in significant morbidity and mortality. Most recently, avacopan, an orally administered selective antagonist of the C5a receptor, was approved by the US Food and Drug Administration as an adjunctive treatment of adult patients with severe, active ANCA-associated vasculitis (granulomatosis with polyangiitis and microscopic polyangiitis) in combination with standard therapy including glucocorticoids. This case study describes a 58-year-old Asian female with severe ANCA-associated vasculitis and acute renal failure who responded to adjunctive therapy with avacopan despite being refractory to rituximab and glucocorticoid therapy.

Pre-clinical Evaluation of Biomarkers for Early Detection of Nephrotoxicity Following Alpha-particle Radioligand Therapy

Purpose

Cancer treatment with alpha-emitter-based radioligand therapies (α-RLTs) demonstrates promising tumor responses. Radiolabeled peptides are filtered through glomeruli, followed by potential reabsorption of a fraction by proximal tubules, which may cause acute kidney injury (AKI) and chronic kidney disease (CKD). Because tubular cells are considered the primary site of radiopeptides' renal reabsorption and potential injury, the current use of kidney biomarkers of glomerular functional loss limits the evaluation of possible nephrotoxicity and its early detection. This study aimed to investigate whether urinary secretion of tubular injury biomarkers could be used as additional non-invasive sensitive diagnostic tool to identify unrecognizable tubular damage and risk of long-term α-RLTs nephrotoxicity.

Methods

A bifunctional cyclic peptide, melanocortin ligand-1(MC1L), labeled with [ 203 Pb]Pb-MC1L, was used for [ 212 Pb]Pb-MC1L biodistribution and absorbed dose measurements in CD-1 Elite mice. Mice were treated with [ 212 Pb]Pb-MC1L in a dose escalation study up to levels of radioactivity intended to induce kidney injury. The approach enabled prospective kidney functional and injury biomarker evaluation and late kidney histological analysis to validate these biomarkers.

Results

Biodistribution analysis identified [ 212 Pb]Pb-MC1L reabsorption in kidneys with a dose deposition of 2.8, 8.9, and 20 Gy for 0.9, 3.0, and 6.7 MBq injected [ 212 Pb]Pb-MC1L doses, respectively. As expected, mice receiving 6.7 MBq had significant weight loss and CKD evidence based on serum creatinine, cystatin C, and kidney histological alterations 28 weeks after treatment. A dose-dependent urinary Neutrophil gelatinase-associated lipocalin (NGAL, tubular injury biomarker) urinary excretion the day after [ 212 Pb]Pb-MC1L treatment highly correlated with the severity of late tubulointerstitial injury and histological findings.

Conclusion

urine NGAL secretion could be a potential early diagnostic tool to identify unrecognized tubular damage and predict long-term α-RLT-related nephrotoxicity.

Progression of chronic kidney disease among black patients attending a tertiary hospital in Johannesburg, South Africa

BACKGROUND

Chronic kidney disease (CKD) is a major public health issue worldwide and is an important contributor to the overall non-communicable disease burden. Chronic kidney disease is usually asymptomatic, and insidiously and silently progresses to advanced stages in resource limited settings.

METHODOLOGY

A prospective longitudinal study was carried out on black patients with CKD attending the kidney outpatient clinic at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in South Africa, between September 2019 to March 2022. Demographic and clinical data were extracted from the ongoing continuous clinic records, as well as measurements of vital signs and interviews at baseline and at follow up. Patients provided urine and blood samples for laboratory investigations as standard of care at study entry (0) and at 24 months, and were followed up prospectively for two (2) years. Data were descriptively and inferentially entered into REDcap and analysed using STATA version 17, and multivariable logistic regression analysis was used to identify predictors of CKD progression.

RESULTS

A total of 312 patients were enrolled into the study, 297 (95.2%) patients completed the study, 10 (3.2%) patients were lost to follow and 5 (1.6%) patients died during the study period. The prevalence of CKD progression was 49.5%, while that of CKD remission was 33% and CKD regression was 17.5%. For patients with CKD progression the median age at baseline was 58 (46-67) years, the median eGFR was 37 (32-51) mL/min/1.73 m2, median urine protein creatinine ratio (uPCR) was 0.038 (0.016-0.82) g/mmol and the median haemoglobin (Hb) was 13.1 (11.7-14.4) g/dl; 95.2% had hypertension, 40.1% patients had diabetes mellitus and 39.5% had both hypertension and diabetes mellitus. Almost half (48.3%) of patients with CKD progression had severely increased proteinuria and 45.6% had anaemia. Variables associated with higher odds for CKD progression after multivariable logistic regression analysis were severely increased proteinuria (OR 32.3, 95% CI 2.8-368.6, P = 0.005), moderately increased proteinuria (OR 23.3, 95% CI 2.6-230.1, P = 0.007), hypocalcaemia (OR 3.8, 95% CI 1.0-14.8, P = 0.047), hyponatraemia (OR 4.5, 95% CI 0.8-23.6, P = 0.042), anaemia (OR 2.1, 95% CI 1.0-4.3, P = 0.048), diabetes mellitus (OR 1.8, 95% CI 0.9-3.6, P = 0.047), elevated HbA1c (OR 1.8, 95% CI 1.2-2.8, P = 0.007) and current smoking (OR 2.8, 95% CI 0.9-8.6, P = 0.049).

CONCLUSION

Our study identified a higher prevalence of CKD progression in a prospective longitudinal study of black patients with CKD compared with literature reports. CKD Progression was associated with proteinuria, diabetes mellitus, elevated HbA1c, anaemia, hypocalcaemia, hyponatraemia and current smoking in a cohort of black patients with CKD who had controlled hypertension and diabetes mellitus at baseline.