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Y Kiyoshi

Publications and source records attributed to Y Kiyoshi.

12 recordsLinked to original sources

Macrophage subclasses and proliferation in childhood IgA glomerulonephritis.

We immunohistologically compared the number of intraglomerular infiltrating cells in 14 children with poststreptococcal acute glomerulonephritis (PSAGN) and 20 children with immunoglobulin A glomerulonephritis (IgAGN) with histological characteristics similar to those of PSAGN to explain the difference in clinicopathological characteristics between these two diseases. Immunohistological study was performed in kidney tissues from these patients by using monoclonal antibodies of T-cell marker (CD3 and CD45RO), B-cell marker (CD20), neutrophil marker (CD15), macrophage marker (CD68), four subclasses of macrophages (early-stage, acute-stage, chronic-stage, and mature inflammatory macrophage marker), and proliferating cell nuclear antigen (PCNA). The 34 patients were classified into three stages according to the time from the detection of urinary abnormalities to biopsy. Intraglomerular immunopositive cells were expressed as the number of cells per glomerulus. There were more intraglomerular positive cells of CD15, CD68, and the four macrophage subclasses in PSAGN than IgAGN. The number of intraglomerular infiltrating macrophages decreased with time in PSAGN, whereas the number of macrophages in IgAGN remained constant at all stages. Intraglomerular infiltration of acute-stage inflammatory macrophages alone was evident in IgAGN. Both the number of intraglomerular proliferating macrophages (PCNA-positive plus CD68-positive cells) and proportion of proliferating macrophages/total macrophages were greater in IgAGN than PSAGN. Normal urinalysis results were evident in all patients with PSAGN during follow-up, and urinary abnormalities persisted in 18 patients with IgAGN. In conclusion, differences in the maturity of infiltrating macrophages and number of proliferating macrophages are associated with the different clinicopathological characteristics in children with PSAGN and IgAGN.

Acute Disease↗

Prognosis of renal amyloidosis: a clinicopathological study using cluster analysis.

Progression of renal amyloidosis is associated with severe proteinuria or nephrotic syndrome, and various mechanisms have been postulated to explain these complications. We studied the acceleration of proteinuria and reduced renal function by cluster analysis using clinical parameters, renal histological findings, type of renal amyloidosis and follow-up data. We divided 97 cases into three groups of renal amyloidosis. Accelerated progression correlated with serum creatinine (s-Cr) levels at renal biopsy and histological grade of renal damage by amyloid deposition (p < 0.0001). The most influential prognostic factors (s-Cr level > or =2.0 mg/dl) were tubulointerstitial and vascular damage induced by amyloid deposition at biopsy (odds ratio 96.9 and 69.2, respectively). In addition, we found amyloidosis type amyloid associated (AA) correlated with more amyloid-mediated vascular and tubulointerstitial damage than amyloidosis type amyloid light chain (AL) (p < 0.001, p < 0.01, respectively). Proteinuria and nephrotic syndrome were more severe in cases of amyloidosis AL than in amyloidosis AA (p = 0.076). In conclusion, less tubulointerstitial and vascular damage was caused by amyloid deposition; this was slowly progressive. Amyloid AA was detected in tubulointerstitial tissue and vessels more frequently than amyloid AL. Heavy proteinuria and/or nephrosis were not indicators of rapid progression.

Adult↗

Benign nephrosclerosis: incidence, morphology and prognosis.

AIMS: Study of benign nephrosclerosis (BNS) is often mixed up with IgA nephritis (IgAN) associated with hypertension or thin basement membrane disease (TBMD). Here we examined the clinicopathological features, incidences and prognosis of decompensated BNS. MATERIALS AND METHODS: BNS was identified in 590 (8.3%) adult cases among 7,108 renal biopsies of a mean age of 56.5 years (male: female ratio = 2.5:1). The post-biopsy follow-up period ranged from 3 to 22 years (10.1 +/- 4.6 years). RESULTS: Patients with progressive BNS were more likely to develop end-stage renal disease within 5 years of biopsy. Poor prognostic factors included poor or no control of arterial blood pressure by anti-hypertensive drugs, global glomerulosclerosis (GS) (> or = 41%) at biopsy, presence of collapsed glomeruli and/or segmented or semi-global GS. Tubulointerstitial damage, glomerular hypertrophy and loop dilatation were secondary to GS. Gender, duration of HT and onset of HT to biopsy were not significant factors. CONCLUSION: GS in BNS is due to ischemia induced by luminal narrowing or obstruction of preglomerular vessels, and glomerular HT due to loss of autoregulation in preglomerular vessels (irregularly shaped atrophic or segmented medial smooth muscle cells, with expansion of extracellular matrix with or without fibrous intimal thickening). GS resulted in luminal dilatation. Both pathological changes affecting the glomerulus may occur in the same kidney and different nephron units.

Female↗

Cadmium induces osteomalacia mediated by proximal tubular atrophy and disturbances of phosphate reabsorption. A study of 11 autopsies.

Osteomalacia of cadmium (Cd) poisoning (Itai-Itai disease) is induced by renal tubular dysfunction; however, the precise pathological changes and mechanisms have not been adequately elucidated. Of the 25 inhabitants in a Cd-polluted area who developed chronic tubular proteinuria, 22 individuals died over a 16-year period. Autopsies were performed in 11 cases and osteomalacia was detected in 9 cases (mean age at death 82.2 +/- 7.8 years; 1 man and 8 women). Histologically, osteomalacia occurred coincidentally with diffuse atrophy of the proximal tubules, moderate thickening of the tubular basement membrane and mild interstitial fibrosis in the renal cortex. Ultrastructurally, mitochondria in the proximal tubules were decreased in number and showed abnormal structure, while membrane enzymes, such as 5'-nucleotidase and ALPase, were still well preserved in their brush border. Glomeruli and distal tubules were minimally damaged. Severity of osteomalacia correlated with the damage of the proximal tubules as well as reduced serum calcium (Ca), serum Ca x phosphorus (P) and hematocrit, increased urine beta2-microglobulin, lysozymes, N-acetyl-b-D-glucosaminidase, retinol binding protein, creatinine, and reduced percent tubular reabsorption of phosphate. Multiple regression analysis showed that among these factors, serum Ca x P was an independent factor for predicting the severity of osteomalacia. Our findings suggest that osteomalacia by Cd poisoning causes degenerative changes in the proximal tubules, especially in mitochondria, which might affect the disturbance of the intracellular active transport energy system for calcium and phosphorus, resulting in osteomalacia.

5'-Nucleotidase↗

A clinical and pathological study on the characteristics and factors influencing the prognosis of crescentic glomerulonephritis using a cluster analysis.

Crescentic glomerulonephritis (CrGN) is expressed by a rapidly progressive lesion. However, there is no unanimous view on the factors that affect the prognosis. We carried out a follow-up study of 109 CrGN patients consisting of 54 males (age 55.3 +/- 15.7) and 55 females (age 54.0 +/- 16.3) by a cluster analysis using pathomorphological parameters at the time of biopsy, and thus found two categories which were significantly different regarding the speed of progress (P = 0.0249). The component factors of rapidly progressive CrGN included a combination of several factors such as: (i) a high frequency of crescents; (ii) frequent sclerosis and hyalinosis in the glomeruli with crescents; (iii) extensive tubulo-interstitial damage (cellular, fibrocellular and fibrous) in the renal cortex; (iv) hyperproteinuria; (v) high mean blood pressure; and (vi) anemia. Thus, the prognosis of CrGN is regulated by no single factor but instead by a complex combination of mutually associated factors.

Adolescent↗

Glomerular score as a prognosticator in IgA nephropathy: its usefulness and limitation.

Glomerular sclerosis, mesangial hypercellularity, extracapillary lesions, interstitial fibrosis, and vascular sclerosis have been reported to be the significant pathologic prognosticators in IgA nephropathy (IgAN). We developed our own scoring for the following main glomerular changes in 248 patients with IgAN: 1) glomerular hypercellularity (mesangial and endocapillary), 2) segmental lesions such as tuft adhesion, crescent and segmental sclerosis, 3) global glomerular sclerosis. Indices of each lesion were semiquantitatively determined. The sum of these three indices was defined to be a glomerular score. We found that a glomerular score significantly related to the outcome of patients with IgAN in univariate life table analysis. We also semiquantitatively determined total score including tubulo-interstitial and vascular lesions as well as glomerular score and compared the predictive power as a prognosticator between glomerular score and total score. Using Cox's proportional Hazard model and log-likelihood ratio test, we confirmed that predictive power of glomerular score was better than that of total score. Furthermore, we assessed the reproducibility of glomerular score using Kappa statistics. Three pathologists read 100 biopsies which were randomly selected from the materials and all pathologists read them twice. A value of Kappa between the first and second observation of pathologist A, B and C was 0.68, 0.71 and 0.60, respectively. Values of Kappa between Pathologist A and B were ranging from 0.45 to 0.47, those between Pathologist A and C from 0.30 to 0.36, and finally those between Pathologist B and C were ranging from 0.12 to 0.23. Therefore, intra-observer reproducibility was nearly excellent. And inter-observer reproducibility between Pathologist A and B was satisfactory. However, inter-observer reproducibility between Pathologist A and C and between B and C was not satisfactory. We feel our scoring system is very convenient and easy to be understood as a prognosticator in patients with IgAN. It, however, should be used by one pathologist because of excellent intra-observer reproducibility and rather unsatisfactory inter-observer reproducibility.

Female↗

[Severity of glomerular damage with IgA nephropathy and renal prognosis: a comparison between pattern classification and calculated classification].

In our laboratory, a semi-quantitative pattern classification (PC) for the distribution pattern of glomerular sclerotic lesions in biopsied renal specimens with IgA nephropathy has been utilized, and found to be quite beneficial for predicting the patient's prognosis. In the present study conducted to re-evaluate this classification, 503 patients with IgA nephropathy (male/female, 256/247; mean age: 32.1 +/- 13.5 yrs; follow-up: 9.3 +/- 4.5 yrs) were used. The patients had been divided originally into 5 groups based on a previous PC: minimal, mild, moderate, severe and advanced groups. Their glomerular lesions were classified as mild, moderate, severe and global sclerosis, and were given scores of 1-4 points. The mean glomerular score was then calculated for each patient, as a value of the calculated classification (CC), and all patients were then re-divided into 5 groups based on their scores. The renal survival curves in the CC were similar to those in PC, and no significant differences in the renal survival rates were found between the classifications in each group, thus suggesting that the CC has a similar predictive power for renal survival. Although 7 of 39 cases (18%) with global sclerosis in PC groups 4 and 5 shifted down to CC group 3, of 61 patients with global sclerosis in PC group 1 who had a good prognosis, 26 cases (43%) shifted up to the CC group 2 and 6 cases (8%) changed to the CC group 3. As a result, the predictive power in patients in the lower CC groups was lost for the renal survival rate. In conclusion, statistical comparison between the PC and CC groups revealed that global sclerosis presents in non/minimally affected glomeruli as a nonspecific alteration. Severely advanced cases also possess a high incidence of globally sclerotic glomeruli (87%), and therefore the occurrence of global sclerosis may involve two different pathogenic mechanisms.

Adolescent↗

[Evaluation of the severity of glomerular damage in IgA nephropathy: significance of hyaline glomeruli in pattern classification].

Hyaline glomeruli are observed frequently in biopsied samples with mild to severe glomerular damage. We thus investigated whether or not all hyaline glomeruli have the same semiquantitative values in order to predict accurately the renal prognosis. We histopathologically studied 503 patients with IgA nephropathy (256 males and 247 females; mean age: 32.1 +/- 13.5 yrs), whose prognoses were followed for more than 3 yrs (mean follow-up period: 9.3 +/- 4.5 yrs). Cases with severely damaged prolifero-sclerotic glomeruli showed poor prognoses (severely damaged glomeruli: (-) vs ( renal death rate: 6% vs 52%, p < 0.0001; the 15 year-survival rate: 89% vs 52%, p < 0.0001) and hyaline glomeruli were seen in 68% of the cases. Hyaline glomeruli were observed in 29% of the cases with mild glomerular damage. However, the renal prognosis was not affected by the presence of hyaline glomeruli based on the analysis of the generalized Wilcoxon test. These results indicated that hyaline glomeruli express two different characteristics for renal prognosis. Therefore, the appearance of hyaline glomeruli alone is less important for the prediction of renal prognosis, but the appearance of both glomeruli with hyalinosis and those with severe damage was found useful in accurately predicting the renal prognosis.

Adolescent↗

[Importance of the duration from the onset of a urinary abnormality until a biopsy is performed: a multivariate analysis on the application of renal biopsy for patients with IgA nephropathy].

To clarify the importance of the duration from the onset of a urinary abnormality until a biopsy is actually performed (UA-Bx time) in making a renal prognosis, we investigated 496 patients with IgA nephropathy (male/female: 222/274, mean age: 33.0 +/- 13.7 yrs, mean follow-up period: 10.8 +/- 4.3 yrs). All patients were found to have a urinary abnormality, including both hematuria and proteinuria, at clinical onset while demonstrating a normal renal function, and showing a serum creatinine level of < or = 1.2 mg/dl or a creatinine clearance level of > or = 80 ml/min. The UA-Bx time was divided into 3 groups: < 1 yrs (S-G), 1 < or = < 3 yrs (M-G), > or = 3 yrs (L-G). The severity of glomerular damage was divided into 5 groups based on the occupational rate of segmental sclerotic glomeruli. Based on a multivariate analysis of independent prognostic factors relating to renal death, the severity of glomerular damage was the most independent factor, while the UA-Bx time showed no risk for renal death. However, based on a multivariate analysis of the UA-Bx time regarding the timing of a renal biopsy, patients in L-G, which had the most glomerular damage, showed twice the hazard ratio as those in S-G or M-G and the difference was significant. These results thus indicate that because the glomerular damage is able to progress for 3 yrs or longer after the clinical onset of renal disease, a renal biopsy should therefore be performed within 3 yrs from the clinical onset in patients demonstrating both hematuria and proteinuria when such patients are also suspected of having IgA nephropathy.

Adolescent↗

[A case with acute suppurative thyroiditis due to Eikenella corrodens and alpha-Streptococcus].

A 6-year-old girl with acute suppurative thyroiditis is reported. She suffered from suppurative thyroiditis twice, and E. corrodens and alpha-streptococcus were grown from the abscess each time. They were sensitive to antibiotics used, but surgical drainage was necessary to cease to inflammation each time. E. corrodens seemed to be a causative organism with or without another organism in compromised patients and/or patients with anatomical abnormalities. The presented patient was supposed to have some anatomical abnormality such as an internal fistula from the piriform sinus connecting the perithyroidal space, however, no abnormalities were detected during these episodes.

Acute Disease↗