Glomerular hyperfiltration in children with cancer: prevalence and a hypothesis.
BACKGROUND
Glomerular hyperfiltration has recently been reported in children with malignancies and has been attributed to increased solute from breakdown of tumor tissues.


OBJECTIVE
To evaluate the prevalence of hyperfiltration in the pediatric oncology population and explore its pathophysiological mechanism.


METHODS
Tc-99 m diethylenetriaminepentaacetic acid (DTPA) glomerular filtration rate (GFR) examinations (437 studies) and medical records of 177 patients <21 years of age diagnosed with a malignancy between January 2005 and October 2013 were retrospectively reviewed. Hyperfiltration was defined as a GFR ≥ 160 ml/min/1.73 m2.


RESULTS
Seventy-seven (43.5%) patients had hyperfiltration in at least one GFR exam. A significantly higher percentage of patients with central nervous system (CNS) tumors (63.6%) had hyperfiltration when compared to other tumor types (27.3%, P < 0.001). No association was found between hyperfiltration and age, gender, race or bone marrow involvement. There was a significant trend toward decreasing hyperfiltration after the second cycle of chemotherapy (P = 0.006) and a significant increase in subjects with low GFR (<100 ml/min/1.73 m2) with increasing number of cycles of chemotherapy (P = 0.005).


CONCLUSIONS
Glomerular hyperfiltration is common in children with malignancies at diagnosis and during initial cycles of chemotherapy. It is particularly prevalent in patients with central nervous tumors, which are frequently smaller in volume. Therefore, the pathophysiological mechanism of hyperfiltration cannot be explained solely on the basis of large tumor volume and subsequent cell breakdown. We hypothesize that host hypermetabolic state plays an important role in pathophysiology of hyperfiltration.
Division of Diagnostic Imaging and Radiology, Children's National Medical Center, 111 Michigan Ave. NW, Washington, DC, 20010, USA.|Department of Radiology, Boston Children's Hospital, Boston, MA, USA.
Neha S
NS
Kwatra
Department of Hematology/Oncology, Children's National Medical Center, Washington, DC, USA.
Holly J
HJ
Meany
Department of Cardiology, Boston Children's Hospital, Boston, MA, USA.
Sunil J
SJ
Ghelani
Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
David
D
Zahavi
Division of Diagnostic Imaging and Radiology, Children's National Medical Center, 111 Michigan Ave. NW, Washington, DC, 20010, USA.
Nayan
N
Pandya
Division of Diagnostic Imaging and Radiology, Children's National Medical Center, 111 Michigan Ave. NW, Washington, DC, 20010, USA. mmajd@childrensnational.org.
Massoud
M
Majd
D002648:Child; D002675:Child, Preschool; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007223:Infant; D007674:Kidney Diseases / Q000503:physiopathology*; D008297:Male; D009369:Neoplasms / Q000188:drug therapy / Q000503:physiopathology*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D016284:Technetium Tc 99m Pentetate / Q000031:analogs & derivatives
C481867:technetium Tc 99m diethylene triamine pentaacetic acid, dimethyl ester; D016284:Technetium Tc 99m Pentetate
Cancer; Children; Glomerular filtration rate; Glomerular hyperfiltration; Hypermetabolism; Tc-99 m diethylenetriaminepentaacetic acid