Skip to main content
SpringerLink
Log in

Utility of fractional excretion of urea in the differential diagnosis of acute kidney injury in children

  • Original Article
  • Published:
Pediatric Nephrology Aims and scope Submit manuscript

Abstract

Introduction

The fractional excretion of sodium (FENa) has been used as an index for the differential diagnosis of acute tubular necrosis (ATN) and prerenal acute kidney injury (AKI). The reliability of this index, however, decreases with the use of the diuretic agent furosemide. The fractional excretion of urea nitrogen (FEUN) has been shown to be useful in such settings in adults. The objective of this study was to examine whether FEUN is also useful in these settings in children.

Methods

We assessed 102 episodes of AKI in 74 children, classifying these into three groups based on history, physical examination, urine examination and subsequent clinical course: (1) prerenal AKI without furosemide (N = 37), (2) prerenal AKI with furosemide (N = 32) and (3) ATN (N = 33).

Results

Of the 37 prerenal AKI episodes without furosemide, 35 showed low FENa of <1 %, with an overall average of 0.35 ± 0.11 %, whereas prerenal AKI with furosemide (1.63 ± 0.37 %) and ATN (8.76 ± 2.11 %) were associated with a higher FENa. FEUN in the clinical setting of prerenal AKI was lower than that in ATN (27.9 ± 2.1 vs. 51.6 ± 3.8 %, respectively) and, in contrast to FENa, not significantly different between the categories of prerenal AKI with and without furosemide (29.2 ± 3.1 vs. 25.1 ± 2.9, respectively). The sensitivity of FEUN <35 % was 75 % in prerenal AKI with furosemide, whereas that of FENa was 53 %.

Conclusions

FEUN is useful in detecting prerenal AKI in children administered furosemide.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  1. Espinel CH (1976) The FENa test. Use in the differential diagnosis of acute renal failure. JAMA 236:579–581

    Article  CAS  PubMed  Google Scholar 

  2. Zarich S, Fang LS, Diamond JR (1985) Fractional excretion of sodium. Exceptions to its diagnostic value. Arch Intern Med 145:108–112

    Article  CAS  PubMed  Google Scholar 

  3. Diskin CJ, Stokes TJ, Dansby LM, Radcliff L, Carter TB (2010) Toward the optimal clinical use of the fraction excretion of solutes in oliguric azotemia. Ren Fail 32:1245–1254

    Article  PubMed  Google Scholar 

  4. Kaplan AA, Kohn OF (1992) Fractional excretion of urea as a guide to renal dysfunction. Am J Nephrol 12:49–54

    Article  CAS  PubMed  Google Scholar 

  5. Carvounis CP, Nisar S, Guro-Razuman S (2002) Significance of the fractional excretion of urea in the differential diagnosis of acute renal failure. Kidney Int 62:2223–2229

    Article  CAS  PubMed  Google Scholar 

  6. Fahimi D, Mohajeri S, Hajizadeh N, Madani A, Esfahani ST, Ataei N, Mohsseni P, Honarmand M (2009) Comparison between fractional excretions of urea and sodium in children with acute kidney injury. Pediatr Nephrol 24:2409–2412

    Article  PubMed  Google Scholar 

  7. Morgan DB, Carver ME, Payne RB (1977) Plasma creatinine and urea: creatinine ratio in patients with raised plasma urea. Br Med J 2:929–932

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group (2012) KDIGO clinical practice guideline for acute kidney injury. Kidney Int Suppl 2:1–138

    Article  Google Scholar 

  9. Pepin MN, Bouchard J, Legault L, Ethier J (2007) Diagnostic performance of fractional excretion of urea and fractional excretion of sodium in the evaluations of patients with acute kidney injury with or without diuretic treatment. Am J Kidney Dis 50:566–573

    Article  PubMed  Google Scholar 

  10. Diskin CJ, Stokes TJ, Dansby LM, Radcliff L, Carter TB (2010) The comparative benefits of the fractional excretion of urea and sodium in various azotemic oliguric states. Nephron Clin Pract 114:c145–150

    Article  CAS  PubMed  Google Scholar 

  11. Quigley R, Lisec A, Baum M (2001) Ontogeny of rabbit proximal tubule urea permeability. Am J Physiol Regul Integr Comp Physiol 280:R1713–1718

    CAS  PubMed  PubMed Central  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Pediatrics, Hiratsuka Kyosai Hospital, Kanagawa, Japan

    Hisayo Fujita

  2. Department of Pediatrics, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan

    Masayoshi Shinjoh, Tomohiro Ishii & Midori Awazu

Authors
  1. Hisayo Fujita
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Masayoshi Shinjoh
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Tomohiro Ishii
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Midori Awazu
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Midori Awazu.

Ethics declarations

The ethics committee at Keio University School of Medicine approved this study. Parental consents were not obtained but the option of opting out was provided.

Disclosure

The authors declare that there is no conflict of interest to disclose.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fujita, H., Shinjoh, M., Ishii, T. et al. Utility of fractional excretion of urea in the differential diagnosis of acute kidney injury in children. Pediatr Nephrol 31, 1349–1353 (2016). https://doi.org/10.1007/s00467-016-3366-9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00467-016-3366-9

Keywords

Search

Navigation