Tsuyoshi Izumotani

Risk factors for osteoporosis in men

Abstract. We evaluated the risk factors for osteoporosis in men. The subjects of this study consisted of 686 healthy middle-aged (40–59 years) men who had undergone bone mineral density (BMD) measurement and medical examination, including physical strength. BMD of L2-4 was measured at the anterior-posterior position, using dual X-ray absorptiometry. Physical investigations, such as height, weight, and physical strength, were carried out on the examination day. Details of tobacco and alcohol consumption, exercise, and food intake were described on a questionnaire completed by the subjects. Sixty-five (9.5%) of the 686 subjects had a BMD less than 2.5 SD below the peak bone mass (PBM), 182 (26.5%) had a BMD between 1 SD and 2.5 SD below the PBM; and 439 (64.0%) had a BMD no less than 1 SD below the PBM. Body mass index (BMI) and leg strength were significant positive determinants of BMD, and smoking was a significant negative determinant on multiple regression analysis, with a coefficient of determination of 9.5%. Calcium intake, exercise, and alcohol consumption were not significant determinants of BMD. These results suggest that poor lifestyle behaviors (i.e., smoking) accelerate the reduction of bone density.

Morphological studies of mesothelial cells in CAPD effluent and their clinical significance

We studied the mesothelial cells in the effluent of patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and their relationship with CAPD duration, peritoneal function, peritoneal sclerosis (PS), and sclerosing encapsulating peritonitis (SEP) in 49 patients (26 men, 23 women) treated for 3 to 161 months with CAPD. Three patients had SEP and five patients had PS. The overnight effluent was drained and centrifuged. The cell differentiation and surface area of mesothelial cells were studied by a computed light microscope system after cytospin preparation staining. The surface area of 50 cells was measured. The mesothelial cells were classified into three types according to their morphological appearance: normal cell type, with a mean surface area of 335.6+/-31.0 microm2 and mean nucleocytoplasmic ratio (N/C ratio) of 0.66+/-0.01; dyskaryotic cell type, with a mean surface area of 570.5+/-35.9 microm2 and N/C ratio 0.58+/-0.06; and giant cell type, with a mean surface area of 1,821.0+/-68.8 microm2 and N/C ratio of 0.06+/-0.01. There was a low but significant correlation between the fast peritoneal equilibration test and surface area (r=0.495; P=0.0120) and a highly significant correlation between CAPD duration and mean surface area (r=0.719; P < 0.0001). This increased cell surface area was because of both an increased surface area of normal and dyskaryotic cells and an increase in the number of dyskaryotic and giant cells. The mean surface area in patients with SEP was 709.3+/-125.4 microm2 and that in patients with PS was 586.6+/-55.2 microm2. Giant cells were found in the effluent of all three patients with SEP and three of the patients with PS. In conclusion, a marked correlation was found between the surface area of effluent mesothelial cells and the duration of CAPD. Giant cells were almost always found in the effluent of patients with SEP and PS. The surface area of mesothelial cells in the effluent might reflect morphological changes in the peritoneum during CAPD. These morphological changes and the measurement of the size of mesothelial cells may predict critical derangement of peritoneal membrane.

An Adult Case of Fanconi Syndrome Due to a Mixture of Chinese Crude Drugs

We examined a 35-year-old male case of acquired Fanconi syndrome induced by a mixture of Chinese crude drugs. Renal glycosuria, hypokalemia, hypophosphatemia, metabolic acidosis, a low threshold of tubular bicarbonate excretion, and generalized aminoaciduria were observed after the patient had taken the drugs for 6 months. When he stopped taking them, all laboratory data improved. He took the drugs again on his own judgment, leading to a second bout of Fanconi syndrome. This is the first case in which Chinese crude drugs have been known to cause acquired Fanconi syndrome.

Correlation between Peritoneal Mesothelial Cell Cytology and Peritoneal Histopathology with Respect to Prognosis in Patients on Continuous Ambulatory Peritoneal Dialysis

Background: Sclerosing encapsulating peritonitis (SEP) is a serious complication seen in patients on long-term continuous ambulatory peritoneal dialysis (CAPD). We have previously reported that mesothelial cells in effluent dialysate significantly increased in size as the duration of CAPD progressed. In this study, we investigated the relationship between mesothelial cytology, histopathology of the peritoneum, and clinical outcomes of 34 CAPD patients. Methods: When peritoneal dialysis catheters were inserted (n = 7) or removed (n = 27), a peritoneal biopsy was performed and results compared with mesothelial cytology in effluent dialysate. Results: A significant positive correlation was noted between the duration of CAPD and the surface area of peritoneal mesothelial cells (r = 0.721, p < 0.0001). The surface area of mesothelial cells in peritoneal sclerosis (n = 9; 584 ± 97 µm2) was significantly greater than in peritoneal fibrosis (n = 14; 389 ± 26 µm2, p < 0.05), pathologic acute peritonitis (n = 3; 223 ± 10 µm2, p < 0.005), and normal peritoneum (n = 7; 247 ± 12 µm2, p < 0.001). The surface area in sclerosing peritonitis (n = 1; 1,200 µm2) was greater than that of all the others. Giant cells were found in the 1 case with sclerosing peritonitis and in 3 of 9 cases with peritoneal sclerosis, although they were found in only 1 of 14 patients with peritoneal fibrosis and in none of those with pathologic acute peritonitis or normal peritoneum. As the surface area of mesothelial cells increased to more than 400 µm2 and giant cells appeared in the effluent, the frequency of peritoneal sclerosis and/or clinical SEP increased. Conclusion: An increase in the mesothelial cell surface area and the emergence of giant cells in the effluent indicate advanced peritoneal histopathology, and may be useful indicators to determine appropriate timing of discontinuation of CAPD to prevent the development of SEP.