Influence of muscle mass on the estimation of glomerular filtration rate in Japanese terminal cancer patients

The role of urinary N-acetyl-β-D-glucosaminidase in early detection of acute kidney injury among pediatric patients with neoplastic disorders in a retrospective study

Background

The 1-year cumulative incidence of AKI reportedly is high (52%) in pediatric neoplastic disorders. About half of these events occur within 2 weeks. However, subclinical AKI episodes may remain unrecognized by the conventional creatinine-based approaches. We investigated the diagnostic value of urinary N-acetyl-β-D-glucosaminidase (uNAG) as an early marker of acute kidney injury (AKI).

Methods

In our retrospective study, 33 children with neoplastic disorders were inculded who had serial uNAG tests (at least 5 samples/patient) with a total of 367 uNAG measurements. Renal function was determined by cystatin-C and creatinine based GFR, and relative increase of uNAG index (uNAG_RI). We focused on detecting both clinical and subclinical AKI episodes (according to Biomarker-Guided Risk Assessment using pRIFLE criteria and /or elevated uNAG levels) and the incidence of chronic kidney damage.

Results

Sixty episodes in 26 patients, with positivity at least in one parameter of kidney panel, were identified during the observation period. We detected 18/60 clinical and 12/60 subclinical renal episodes. In 27/60 episodes only uNAG values was elevated with no therapeutic consequence at presentation. Two patients were detected with decreased initial creatinine levels with 3 „silent” AKI.

In 13 patients, modest elevation of uNAG persisted suggesting mild, reversible tubular damage, while chronic tubuloglomerular injury occurred in 5 patients.

Based on ROC analysis for the occurence of AKI, uNAGRI significantly indicated the presence of AKI, the sensitivity and specificity are higher than the changes of GFR_Creat. Serial uNAG measurements are recommended for  the reduction of the great amount of false positive uNAG results, often due to overhydratation.

Conclusion

Use of Biomarker-guided Risk Assessment for AKI identified 1.5 × more clinical and subclinical AKI episodes than with creatinine alone in our pediatric cancer patients. Based on the ROC curve for the occurence of AKI, uNAG_RI has relatively high sensitivity and specificity comparable to changes of GFR_CysC. The advantage of serial uNAG measurements is to decrease the number of false positive results.

Trial registration

The consent to participate is not applicable because it was not reqired for ethical approval and it is a retrospectiv study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03416-w.

Evaluation of renal function using cystatin C-based estimated glomerular filtration rate in patients with urothelial carcinoma treated with gemcitabine and cisplatin chemotherapy

WHAT IS KNOWN AND OBJECTIVE

Cisplatin-based chemotherapy is a first-line treatment for advanced or metastatic urinary tract urothelial carcinoma (UC). Accurate assessment of renal function is indispensable for determining cisplatin dosing to enhance the safety and effectiveness of cisplatin. The objective of this study was to assess serum cystatin C (sCys C) levels in patients with urothelial carcinoma and to explore its clinical value as a serum marker of glomerular filtration rate (GFR).

METHODS

This study retrospectively enrolled 18 UC patients treated with a combination of gemcitabine and cisplatin between April 2018 and November 2020. We calculated the estimated GFR (eGFR) based on serum creatinine (sCr) or sCys C and estimated Cr clearance (eCCr) based on sCr. The correlation, bias, accuracy and creatinine height index between eGFR or eCCr and measured GFR (mGFR) based on Cr clearance were calculated from urinary Cr and sCr.

RESULTS AND DISCUSSION

Estimated GFR based on sCys C correlated most strongly with mGFR. Moreover, the bias, mean error, mean absolute error and root mean square error were significantly lower in eGFRs based on sCyc C than in eGFRs based on sCr and eCCr. The correlation between eGFR based on sCys C/mGFR and creatinine height index was weaker than that between eGFR based on sCr/mGFR and creatinine height index, suggesting that sCys C was less affected by muscle mass.

WHAT IS NEW AND CONCLUSION

In UC patients, eGFR based on sCys C reflected renal function more accurately than eGFR based on sCr, suggesting that sCys C may be useful for assessing renal function in clinical practice.