Kidney Week

Abstract: SA-PO1084

The Size of Urinary Podocyte in Focal Segmental Glomerulosclerosis

Session Information

• Pathology and Lab Medicine: Clinical
  October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pathology and Lab Medicine

• 1502 Pathology and Lab Medicine: Clinical

Authors

• Shirai, Yoko, Tokyo Women's Medical University, Tokyo, Japan

Yoko Shirai,

• Miura, Kenichiro, Tokyo Women's Medical University, Tokyo, Japan

Kenichiro Miura,

• Yokoyama, Takashi, Tokyo Women's Medical University, Tokyo, Japan

Takashi Yokoyama,

• Horita, Shigeru, Tokyo Women's Medical University, Tokyo, Japan

Shigeru Horita,

• Iida, Takaya, Tokyo Women's Medical University, Tokyo, Japan

Takaya Iida,

• Taniguchi, Yohei, Tokyo Women's Medical University, Tokyo, Japan

Yohei Taniguchi,

• Nagasawa, Takeshi, Tokyo Women's Medical University, Tokyo, Japan

Takeshi Nagasawa,

• Ban, Hideki, Tokyo Women's Medical University, Tokyo, Japan

Hideki Ban,

• Takagi, Yoko, Tokyo Women's Medical University, Tokyo, Japan

Yoko Takagi,

• Yabuuchi, Tomoo, Tokyo Women's Medical University, Tokyo, Japan

Tomoo Yabuuchi,

• Kaneko, Naoto, Tokyo Women's Medical University, Tokyo, Japan

Naoto Kaneko,

• Ishizuka, Kiyonobu, Tokyo Women's Medical University, Tokyo, Japan

Kiyonobu Ishizuka,

• Hara, Masanori, Niigata Wellness (Iwamuro Health Promotion Center), Niigata, Japan

Masanori Hara,

• Hattori, Motoshi, Tokyo Women's Medical University, Tokyo, Japan

Motoshi Hattori,

Background

Previous reports indicated that the number of urinary podocytes is higher in FSGS with nephrotic range of proteinuria than those in FSGS in remission and minimal change nephrotic syndrome (MCNS) in relapse. To date, the size of urinary podocyte has not been evaluated. In the present study, we examined the size of urinary podocyte in various glomerular diseases including FSGS in children.

Methods

Eight patients with FSGS (primary, n=6; genetic, n=2), 7 patients with MCNS in relapse and 10 patients with glomerulonephritis (GN) were included in the study. GN included IgAN (n=3), IgA vasculitis (n=4), ANCA-associated GN (n=1), lupus GN (n=1), and infection related GN (n=1). Patients with eGFR <60 ml/min/1.73m² were not included. Fresh urine samples of 10ml voided in the morning were obtained and urinary podocyte was detected by immunofluorescence using anti-human podocalyxin monoclonal antibody with a DAPI positive nucleus. The number of urinary podocytes was calculated per 10ml sample. Images of podocalyxin-positive cells were taken under an immunofluorescence microscope with 400-fold magnification and were quantified by image analysis. The size of urinary podocyte was defined as mean area of the podocytes in a field (pixel/cell). Statistical analyses were performed with Wilcoxon tests. Data are expressed as median (IQR). A P value of <0.05 was accepted as statistically significant.

Results

Urinary protein/creatinine ratios (UP/UC) were not significantly different among FSGS, MCNS and GN. The number of urinary podocytes (/10ml) in GN (200 (154.5-200)/10ml) was significantly higher than those in FSGS (81.5 (42.8-140.3)/10ml) and MCNS (68 (35-98)/10ml) (P=0.0225), while there was not a significant difference between FSGS and MCNS. Of note, the size of podocyte in FSGS (2947.9 (2571.4-3400.0) pixel/cell) was significantly larger than those in MCNS (1242.3 (756.0-2214.5) pixel/cell) and GN (859.4 (753.2-1079.3) pixel/cell) (P=0.0034).

Conclusion

This preliminary study suggested that the size of urinary podocyte may be a specific marker of FSGS.