Original Paper
Nephron 1992:61:16-20
Second Department of Pathology, School of Medicine, Fukuoka University, Fukuoka, Japan
Key Words Idiopathic membranous glomerulonephritis Vacuolation of podocytes Clinicopathological correlations Electron-dense deposit size Morphometric analysis
Glomerular Podocyte Vacuolation in Idiopathic Membranous Glomerulonephritis
Abstract Vacuoles in glomerular visceral epithelial cells were found in 149 of 254 patients with idiopathic membranous glomerulonephritis (1 MGN). In the whole popula tion studied, 115 patients were nephrotic, 88 (76.5%) of which were found to have intraepithelial vacuoles. Fifty (35.9%) of 139 non-nephrotic patients had vacuo lated podocytes (p 3 g/day) with hypoproteinemia
S. Takebayashi. 2nd Department of Pathology School of Medicine, Fukuoka University 45-1.7-chome Nanakuma. Jonan-ku Fukuoka 814-01 (Japan)
0 1992 S. Karger AG, Basel 0028 -2766/92/ 0611- 00I6S2.75/0
Downloaded by: Stockholm University Library 130.237.165.40 - 11/16/2018 2:12:46 PM
Tibor Toth Shigeo Takebayashi
( < 4 g/day) hypoalbuminemia (< 3 g/day) and hypercholesterolemia (> 260 mg/dl). One hundred of the 254 patients were followed clinically from the day of the first renal biopsy. Mean duration of follow-up was 7.8 years. For electron-microscopic study, the samples were fixed in 1.4% buffered glutaraldehyde, postfixed in 1% osmium tetroxide and em bedded in Spurr-resin (TAAB) after dehydration. Ultrathin sections were stained with uranyl acetate and lead citrate and examined and photographed using a JEM 100 CX electron microscope. About 20 podocytes from each glomerulus were examined electron-microscopically for vacuolation. Semiquantitative estimates were defined, ac cording to the study of Yoshikawa et al. [4], as: grade 0: no vacuoles seen: grade I: few and small vacuoles observed: grade 2: vacuoles moderate in size and number, and grade 3: large and numerous vacuoles observed. A minimum of 30, with a mean number of 50, consecutive subepithelial and intramembranous electron-dense deposits were measured in at least 2 glomeruli for each of the cases. Areaperimenter analysis was carried out on the enlarged photographs ( x 10,000). An NEC desk computer (PC803I) was used with a modified digitizer RS 232 and a drawing tube. Statistical parameters were calculated fro each group studied. Student’s t test, Fisher’s exact probability test and the % ' test were used in the statistical calculations which were performed on the 'Stax’ Software Program System.
Fig. 1. Numerous large intracytoplasmic vacuoles observed in the podocyte (grade 3). x 1,900.
Results
Fig. 2. Large, empty, balloon-like vacuola observed in the visceral epithelial cell, surrounded by a thin membrane, x 2,900.
17
Downloaded by: Stockholm University Library 130.237.165.40 - 11/16/2018 2:12:46 PM
The sex ratio of the patients was 138 males: 116 females. Their ages ranged from 3 to 76 years with a mean of 43.8 ± 15.5. Of these, 115 (45.2%) were nephrotic at the time of biopsy. The remaining patients had proteinuria which varied from mild to moderate. Hypertension (> 160/95 mm Hg) was observed in 24 patients (10%) at the time of the first renal biopsy. Alteration of podocytes coincided with effacement of their foot processes and cell hypertrophy with formation of microvilli. In 105 of the patients (41.3%), no podocyte vacuo lation was present (grade 0). The biopsy samples of 149 patients (59%) showed intraepithelial vacuolation. Grade 1 vacuolation was noted in 85 biopsies (33.5%), grade 2 vacu olation in 45 (17.7%) and grade 3 vacuolation in 19(7.5%, fig. 1). The majority of the vacuoles were empty, but some of them were filled with finely granular, flocculent or less electron-dense material. The vacuoles were well-sur rounded by a single membrane and condensed cytoplasm (fig. 2). The vacuoles were mostly localized close to the glomerular capillary wall. The podocytic cytoplasma, att ached to the glomerular basement membrane (GBM), changed to dense fibrillar structures parallel to the GBM. Table I shows the distribution of selected clinical, labor atory and morphometric data in relation to the extension of podocyte vacuolation. The age at renal biopsy was signifi-
Table 1. Selected clinical, laboratory and morphometrical data in relation to podocyte vacuolation in 254 patients with IMGN
Features
Podocyte vacuolation grade 0 (n=l()5)
grade 1 (n = 85 )
grade 2 (n=45)
grade 3 (n=19)
i---------------------- ------------------------- 1
Age, years
vacuolation. Grade 0: n = 105; grade 1: n = 85; grade 2: n = 45: grade 3: n = 19. *p
Nephron 1992:61:16-20
Second Department of Pathology, School of Medicine, Fukuoka University, Fukuoka, Japan
Key Words Idiopathic membranous glomerulonephritis Vacuolation of podocytes Clinicopathological correlations Electron-dense deposit size Morphometric analysis
Glomerular Podocyte Vacuolation in Idiopathic Membranous Glomerulonephritis
Abstract Vacuoles in glomerular visceral epithelial cells were found in 149 of 254 patients with idiopathic membranous glomerulonephritis (1 MGN). In the whole popula tion studied, 115 patients were nephrotic, 88 (76.5%) of which were found to have intraepithelial vacuoles. Fifty (35.9%) of 139 non-nephrotic patients had vacuo lated podocytes (p 3 g/day) with hypoproteinemia
S. Takebayashi. 2nd Department of Pathology School of Medicine, Fukuoka University 45-1.7-chome Nanakuma. Jonan-ku Fukuoka 814-01 (Japan)
0 1992 S. Karger AG, Basel 0028 -2766/92/ 0611- 00I6S2.75/0
Downloaded by: Stockholm University Library 130.237.165.40 - 11/16/2018 2:12:46 PM
Tibor Toth Shigeo Takebayashi
( < 4 g/day) hypoalbuminemia (< 3 g/day) and hypercholesterolemia (> 260 mg/dl). One hundred of the 254 patients were followed clinically from the day of the first renal biopsy. Mean duration of follow-up was 7.8 years. For electron-microscopic study, the samples were fixed in 1.4% buffered glutaraldehyde, postfixed in 1% osmium tetroxide and em bedded in Spurr-resin (TAAB) after dehydration. Ultrathin sections were stained with uranyl acetate and lead citrate and examined and photographed using a JEM 100 CX electron microscope. About 20 podocytes from each glomerulus were examined electron-microscopically for vacuolation. Semiquantitative estimates were defined, ac cording to the study of Yoshikawa et al. [4], as: grade 0: no vacuoles seen: grade I: few and small vacuoles observed: grade 2: vacuoles moderate in size and number, and grade 3: large and numerous vacuoles observed. A minimum of 30, with a mean number of 50, consecutive subepithelial and intramembranous electron-dense deposits were measured in at least 2 glomeruli for each of the cases. Areaperimenter analysis was carried out on the enlarged photographs ( x 10,000). An NEC desk computer (PC803I) was used with a modified digitizer RS 232 and a drawing tube. Statistical parameters were calculated fro each group studied. Student’s t test, Fisher’s exact probability test and the % ' test were used in the statistical calculations which were performed on the 'Stax’ Software Program System.
Fig. 1. Numerous large intracytoplasmic vacuoles observed in the podocyte (grade 3). x 1,900.
Results
Fig. 2. Large, empty, balloon-like vacuola observed in the visceral epithelial cell, surrounded by a thin membrane, x 2,900.
17
Downloaded by: Stockholm University Library 130.237.165.40 - 11/16/2018 2:12:46 PM
The sex ratio of the patients was 138 males: 116 females. Their ages ranged from 3 to 76 years with a mean of 43.8 ± 15.5. Of these, 115 (45.2%) were nephrotic at the time of biopsy. The remaining patients had proteinuria which varied from mild to moderate. Hypertension (> 160/95 mm Hg) was observed in 24 patients (10%) at the time of the first renal biopsy. Alteration of podocytes coincided with effacement of their foot processes and cell hypertrophy with formation of microvilli. In 105 of the patients (41.3%), no podocyte vacuo lation was present (grade 0). The biopsy samples of 149 patients (59%) showed intraepithelial vacuolation. Grade 1 vacuolation was noted in 85 biopsies (33.5%), grade 2 vacu olation in 45 (17.7%) and grade 3 vacuolation in 19(7.5%, fig. 1). The majority of the vacuoles were empty, but some of them were filled with finely granular, flocculent or less electron-dense material. The vacuoles were well-sur rounded by a single membrane and condensed cytoplasm (fig. 2). The vacuoles were mostly localized close to the glomerular capillary wall. The podocytic cytoplasma, att ached to the glomerular basement membrane (GBM), changed to dense fibrillar structures parallel to the GBM. Table I shows the distribution of selected clinical, labor atory and morphometric data in relation to the extension of podocyte vacuolation. The age at renal biopsy was signifi-
Table 1. Selected clinical, laboratory and morphometrical data in relation to podocyte vacuolation in 254 patients with IMGN
Features
Podocyte vacuolation grade 0 (n=l()5)
grade 1 (n = 85 )
grade 2 (n=45)
grade 3 (n=19)
i---------------------- ------------------------- 1
Age, years
vacuolation. Grade 0: n = 105; grade 1: n = 85; grade 2: n = 45: grade 3: n = 19. *p
