Abstract: TH-PO612

Proteinuric Renal Injury in an Adolescent with a Distal Partial Trisomy Chromosome 1

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Tosaki, Takeshi, Kawaguchi Municipal Medical Center, Kawaguchi-shi, Saitama, Japan
  • Sasaki, Takaya, Kawaguchi Municipal Medical Center, Kawaguchi-shi, Saitama, Japan
  • Okabe, Masahiro, Kawaguchi Municipal Medical Center, Kawaguchi-shi, Saitama, Japan
  • Honda, Yu, Kawaguchi Municipal Medical Center, Kawaguchi-shi, Saitama, Japan
  • Ishikawa, Masahiro, Kawaguchi Municipal Medical Center, Kawaguchi-shi, Saitama, Japan
  • Tsuboi, Nobuo, The Jikei University School of Medicine, Minato-ku Tokyo-to, Japan
  • Yokoo, Takashi, The Jikei University School of Medicine, Minato-ku Tokyo-to, Japan
Background

Distal partial trisomy 1q is a rare disease, with no previous case reports of renal insufficiency occurring in relation to this chromosomal disorder. We report a case of distal partial trisomy 1q that showed proteinuric renal injury.

Methods

We treated a 17-year-old adolescent with clinical features of low birth weight, mild mental retardation, and mild deafness. When he was 13 years old, he was diagnosed as having a partial trisomy of chromosome 1 from q32.1 to 41 using chromosomal and microarray tests. He showed persistent proteinuria since age 16 and underwent medical check-up at our hospital. Proteinuria was estimated to be approximately 1-2 g/day, although serological examination revealed no abnormal findings. Computed tomography detected no morphological abnormalities of the kidneys other than their slightly small size. Renal biopsy showed no evidence of immune-mediated glomerular diseases, but revealed a very low glomerular density and glomerulomegaly, as evidenced by a marked increase in the estimated mean glomerular volume (10.3 × 106 µm3). Combination therapy with dietary sodium restriction, body weight reduction, and the administration of losartan potassium markedly reduced his proteinuria to 0.3 g/day.

Conclusion

The section of partial trisomy found in this case does not include podocyte-related genes that have been related to proteinuric renal injuries. Thus, in this case, the mismatch between congenital reduction in the number of nephrons due to low birth weight and catch-up growth of whole body size may have resulted in glomerular hyperfiltration and renal injury.
Renal prognosis is poor in patients with a history of low birth weight, which is sometimes complicated in patients with genetic comorbidities. In such patients, where the renal prognosis has not been studied well, continuous follow-up is necessary to evaluate renal complications and inhibit progression of renal disease.