An investigation of 2,093 renal biopsies performed at Tokai University Hospital between 1976 and 2000.

We retrospectively investigated 2,093 renal biopsy procedures performed between 1976 and 2000 at Tokai University Hospital. The study period was divided into 5-year intervals, and the frequencies of each renal disease, age and sex of patients were compared across the study period. Clinical diagnosis was based on WHO criteria. A total of 2,093 patients aged 8 months to 84 years underwent renal biopsy during the study period. The percentage of elderly patients who underwent renal biopsy increased from 1.2% in 1976 - 1980 to 9.9% in 1996 - 2000. IgAN was the most common disease in every 5-year period. CresGN showed an increase from 1 patient (0.3%) in 1976 - 1980 to 15 patients (4.0%) in 1996 - 2000. In contrast, the number of patients with PGN or BRH, MPGN significantly decreased during the study period. Although the criteria for renal biopsy and renal diseases detected are expected to change in the future, renal biopsy will remain an essential procedure for making a definite diagnosis, selection of optimum treatment, and prediction of prognosis.

Renal in situ hybridization studies of extracellular matrix related molecules in type 1 diabetes mellitus.

BACKGROUND/AIM: Progressive expansion of mesangial matrix and glomerular basement membrane thickening represent alterations in the balance between synthesis and degradation of glomerular extracellular matrix (ECM) protein and are hallmarks of diabetic nephropathy. In order to elucidate the basis for this imbalance between the synthesis and the degradation of ECM in renal tissues from patients of type 1 diabetes mellitus (type 1D) with diabetic nephropathy (DN), we examined the expression of alpha1 chain of type IV collagen (IV-C), matrix metalloproteinase-2 and -3 (MMP-2, MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1) and beta-actin mRNA using a high-resolution in situ hybridization with digoxigenin-labeled oligonucleotide. METHODS: Patients were divided into two groups based on both of degree of mesangial expansion using electron microscopic point counting morphometric methods and duration of type 1D: 7 'fast-track' patients were selected for their very rapid development of DN structural changes and 8 'slow-track' patients for their very slow development of DN structural changes. Seven normal human kidney (NHK) tissues were used as controls. RESULTS: Positive cells for each mRNA were observed in glomerular resident cells, including glomerular mesangial, epithelial and endothelial cells and cells of Bowman's capsule. The percentage of glomerular cells positive for IV-C, MMP-2 and MMP-3 mRNA was significantly greater in the 'slow-track' vs. 'fast-track' patients. No significant differences in percentage positive cells was seen for beta-actin mRNA. Furthermore, to elucidate the total number of positive cells per glomerulus for each mRNA, we estimated total cell number of glomerulus using morphometric techniques on light microscopy tissues. The total cell number per glomerulus was significantly greater in 'fast-track' than that in 'slow-track' patients and NHK. The total number of positive cells per glomerulus for MMP-2 in NHK was significantly greater than that in 'slow-track' and 'fast-track' patients. CONCLUSIONS: Thus, IV-C, MMP-2, MMP-3 and TIMP-1 mRNA are expressed in resident glomerular cells in renal tissues from NHK and type 1D. Glomerular alterations in these in situ mRNA expressions sufficient to explain ECM accumulation and DN risk were not uncovered. These largely negative results could be due to methodologic quantitative imprecision or could indicate that post-translational differences account for ECM imbalance in DN. However, these studies make it clear that unraveling the nature of the ECM production/removal imbalance in DN will require careful consideration of alterations in glomerular cell number.

[A case of antiphospholipid antibody syndrome with variable renal histological change despite of poor changes in urinalysis].

We experienced a case of lupus nephritis with antiphospholipid antibody syndrome. A renal biopsy specimen from this patient showed various renal histological changes, but the results of urinalysis were almost normal. The patient was a 56-year-old woman diagnosed as having systemic lupus erythematosus with antiphospholipid antibody syndrome in 1983. In 1998, she had diarrhea and blood gas analysis showed metabolic acidosis. Therefore, she was admitted to our hospital and underwent renal function examination. The glomerular filtration rate was reduced(GFR: 40/ml/min), but urinalysis was almost normal. To examine her renal dysfunction, we performed open renal biopsy. Her renal tissues showed global glomerular sclerosis, mesangial cell proliferation and infiltration of cells in the tubulointerstitial area(WHO II). Furthermore, some arterioles showed organized thrombus formation and recanalization due to the antiphospholipid antibody syndrome. Renal biopsy of patients with lupus nephritis is useful not only for precise diagnosis, but also for the selection of appropriate treatment.

Asian multicenter trials on urinary type IV collagen in patients with diabetic nephropathy.

To investigate the changes of renal type IV collagen turnover in diabetic nephropathy, urinary type IV collagen was measured by a highly sensitive one-step sandwich enzyme immunoassay (EIA). Urinary samples were obtained from 698 diabetic patients and 191 healthy adults. Among the patients, 264 had urinary albumin levels of less than 29 mg/g.creatine (Cr) (Stage I: normoalbuminuric stage), 169 had microalbuminuria from 30 to 299 mg/g.Cr (Stage II: microalbuminuric stage), 84 patients had macroalbuminuria of more than 300 mg/g.Cr and serum Cr of less than 1.1 mg/dl (Stage IIIA: macroalbuminuric stage without renal dysfunction), 97 had macroalbuminuria of more than 300 mg/g.Cr and serum Cr of more than 1.2 mg/dl (Stage IIIB: macroalbuminuric stage with renal dysfunction), and 84 had renal failure (Stage IV). The levels of urinary type IV collagen in Stages II, IIIA, IIIB, and IV were significantly higher than those in Stage I (P < 0.0001). The level of urinary type IV collagen in Stage I (5.00 +/- 0.23 microg/g.Cr; mean +/- SE) was also higher than that in normal adults (3.44 +/- 0.11 microg/g.Cr; mean +/- SE). These levels increased gradually due to progression of the clinical stage of diabetic nephropathy. It appears that the levels of urinary type IV collagen can be a useful marker for detecting renal injuries in diabetes according to our Asian multicenter trials.

[Two cases of episodic angioedema associated with eosinophilia].

We experienced two cases of limb edema of unknown pathogenesis. No evidence was found concerning involvement of the kidneys, heart of other visceral organs. Case 1 was 22-year-old woman. Her white blood cell count increased to 13,100/microliter with 65.0% eosinophils. Case 2 was a 27-year-old woman. Her white blood cell count increased to 23,300/microliter with 67.0% eosinophils. In these cases, extensive diagnostic evaluations revealed no evidence of atopy, neoplasms, collagen-vascular disease, or parasitic infestation. We diagnosed these cases as episodic angioedema with eosinophilia. In both cases, the angioedema improved gradually in parallel with a decrease in the white blood cell count. This disorder is very rare, but it is very important to consider it in differential diagnosis especially for nephrologists.

Evaluation of renal biopsy samples of patients with diabetic nephropathy.

OBJECTIVE: To evaluate the usefulness of renal biopsy in the overall management of patients with diabetes mellitus (DM), we examined the relationship between the clinical parameters and histopathological findings of renal biopsy samples. METHODS: Renal biopsy specimens were obtained from 109 type 2 diabetic patients with proteinuria. Samples were divided into the following two groups: Diabetic Nephropathy (DN) group (n=80) had typical diabetic lesions without other renal diseases, complication group (n=29) had diabetic lesions with other renal diseases. Furthermore, DN group was subdivided into two subgroups: slow progressive group (SP group, n=32), the level of serum creatinine (s-Cr) was normal at the time of renal biopsy and three years after renal biopsy, and fast progressive group (FP group, n=14), the level of s-Cr was normal at the time of renal biopsy but more than doubled three years after renal biopsy. RESULTS: The level of total protein was significantly lower and HbA1c significantly higher in the DN group than in the Complication group. However, other clinical parameters were not significantly different between the two groups. Urinary protein, systolic and diastolic blood pressure in FP group were significantly higher than in SP group. The percentage of sclerotic glomeruli, the severity of mesangial expansion, tubular injury and cell infiltration were significantly greater in FP than in SP group. CONCLUSIONS: Our results indicated that a complete evaluation of renal pathology in DM could not be made by clinical parameters only, and that the progression of DN could be accurately predicted by histopathological evaluation. Therefore, this study emphasizes the importance of renal biopsy in the overall management of patients with DM and/or DN.

[Factors leading to home care of patients in the terminal stage of malignant diseases--a study of 10 cases].

In order to clarify the factors that lead patients in the terminal stage of malignant diseases to home care, we interviewed ten families of such patients. Among factors involving patients, a strong desire to stay at home and to spend time at home with the family were initially required. Adequate understanding of the patients and their diseases was also needed by families. Other factors include guaranteed medical services in emergencies and/or 24 hours/day 7 days/week care. Patients requested referrals to family physicians, visiting nurses or community health services to cover outpatient clinic functions. It is concluded that a strong desire to stay at home, adequate understanding by the family and guaranteed medical services in emergencies were three significant factors leading to home care of patients in the terminal stage of malignant diseases.

Immunohistochemical evidence for an increased oxidative stress and carbonyl modification of proteins in diabetic glomerular lesions.

Advanced glycation end products (AGE) include a variety of protein adducts whose accumulation has been implicated in tissue damage associated with diabetic nephropathy (DN). It was recently demonstrated that among AGE, glycoxidation products, whose formation is closely linked to oxidation, such as carboxymethyllysine (CML) and pentosidine, accumulate in expanded mesangial matrix and nodular lesions in DN, in colocalization with malondialdehyde-lysine (MDA-lysine), a lipoxidation product, whereas pyrraline, another AGE structure whose deposition is rather independent from oxidative stress, was not found within diabetic glomeruli. Because CML, pentosidine, and MDA-lysine are all formed under oxidative stress by carbonyl amine chemistry between protein amino group and carbonyl compounds, their colocalization suggests a local oxidative stress and increased protein carbonyl modification in diabetic glomerular lesions. To address this hypothesis, human renal tissues from patients with DN or IgA nephropathy were examined with specific antibodies to characterize most, if not all, carbonyl modifications of proteins by autoxidation products of carbohydrates, lipids, and amino acids: CML (derived from carbohydrates, lipids, and amino acid), pentosidine (derived from carbohydrates), MDA-lysine (derived from lipids), 4-hydroxynonenal-protein adduct (derived from lipids), and acrolein-protein adduct (derived from lipids and amino acid). All of the protein adducts were identified in expanded mesangial matrix and nodular lesions in DN. In IgA nephropathy, another primary glomerular disease leading to end-stage renal failure, despite positive staining for MDA-lysine and 4-hydroxynonenal-protein adduct in the expanded mesangial area, CML, pentosidine, and acrolein-protein adduct immunoreactivities were only faint in glomeruli. These data suggest a broad derangement in nonenzymatic biochemistry in diabetic glomerular lesions, and implicate an increased local oxidative stress and carbonyl modification of proteins in diabetic glomerular tissue damage ("carbonyl stress").

Follow-up study on urinary type IV collagen in patients with early stage diabetic nephropathy.

Type IV collagen is a major component released from the glomerular and tubular basement membranes. To investigate the alteration of renal type IV collagen turnover in early stage diabetic nephropathy, urinary type IV collagen was measured by a highly sensitive one-step sandwich enzyme immunoassay (EIA). Urinary samples were obtained from 94 diabetic patients without overt proteinuria. Among those patients, 61 were normoalbuminuric and 33 patients were in the microalbuminuric group. Levels of urinary type IV collagen were serially examined at the start of this study and again one year later. The levels of urinary type IV collagen in patients in the microalbuminuric group were significantly higher than those in the normoalbuminuric group (P < 0.01). There was a significant correlation between the concentration of urinary albumin and urinary type IV collagen in both groups (P < 0.05). Twenty-eight patients (45.3%) in the normoalbuminuric group who showed an abnormal elevation of urinary type IV collagen in comparison to the reference range of normal healthy adults (normal range; less than 3.5 microg/g x Cr). Seven (25%) out of these 28 normoalbuminuric patients with increased urinary type IV collagen progressed to the microalbuminuric group one year later. The levels of urinary type IV collagen in such patients were significantly increased. In the 21 patients who stayed within the normoalbuminuric group, the urinary type IV collagen levels were significantly decreased one year later. It appears that the levels of urinary type IV collagen might reflect ongoing alteration of the extracellular matrix (ECM) turnover and might define more specifically the early stage diabetic nephropathy than the detection of microalbuminuria. It is concluded that the serial measurement of urinary type IV collagen can be a useful marker for detecting renal injury in diabetes.

In situ hybridization studies of matrix metalloproteinase-3, tissue inhibitor of metalloproteinase-1 and type IV collagen in diabetic nephropathy.

Progressive expansion of the mesangial matrix is one of the most characteristic histological features of diabetic nephropathy (DN). To determine the balance between the turnover and degradation of extracellular matrix (ECM) in renal tissue of patients with DN, we examined the expression of matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1) and type IV collagen (IV-C) mRNAs using a high-resolution in situ hybridization. Patients were divided into three grades: mild (grade I), moderate (grade II) and severe (grade III) mesangial expansion and tubulointerstitial injury. The relationship between the expression of these mRNAs and degree of glomerular mesangial expansion and interstitial injury was also examined. Cells positive for each mRNA were observed in glomerular resident cells, including glomerular mesangial, epithelial and endothelial cells and cells of Bowman's capsule. A number of tubular epithelial cells and some infiltrating cells in the interstitium also expressed these mRNAs. The expression of MMP-3 mRNA and TIMP-1 mRNA was strongest in glomeruli of grade I and inversely correlated with mesangial expansion. In contrast, the expression of all three types of mRNA was correlated with the degree of interstitial injury. Our results indicate that IV-C, MMP-3 and TIMP-1 mRNAs are expressed in glomerular resident cells, tubular epithelial cells and infiltrating cells in renal tissue of DN, and suggest that their expression changes with the degree of mesangial expansion and interstitial injury. Altered expression of MMP-3 and TIMP-1 may be associated with the progression of DN.

A diabetic case with hemoglobin J-Meerut and low HbA1C levels.

A diabetic patient with hemoglobin (Hb) J-Meerut and low HbA1C levels is reported. An automatic glycohemoglobin analyzer used for the determination of HbA1C revealed an abnormal peak of the peripheral blood obtained from a Japanese female with diabetes. She showed a lower HbA1C level (3.7%) than expected from her fasting plasma glucose (172 mg/dl). High performance liquid chromatography and isoelectric focusing indicated that her abnormal hemoglobin was Hb J-Meerut [alpha 120(H3)Ala-->Glu] and it accounted for 28.3% of the total hemoglobin. Abnormal hemoglobinemia should be considered when a major discrepancy between the levels of HbA1C and fasting plasma glucose is observed.

Significance of urinary type IV collagen in patients with diabetic nephropathy using a highly sensitive one-step sandwich enzyme immunoassay.

Urinary concentrations of type IV collagen in patients with diabetic nephropathy were measured by a highly sensitive, one-step sandwich enzyme immunoassay. Samples from 298 patients with noninsulin-dependent diabetes mellitus (NIDDM) and 80 healthy controls were examined. In diabetic patients with macroalbuminuria or renal insufficiency, the concentrations of urinary type IV collagen were significantly higher than those of diabetic patients with normoalbuminuria or healthy controls (P < 0.001). Urinary type IV collagen concentration in diabetic patients with microalbuminuria was significantly higher than that in diabetic patients with normoalbuminuria or that in healthy controls (P < 0.001). In contrast, there were no significant changes in the concentration of serum type IV collagen between microalbuminuric patients and normoalbuminuric patients. The area under the receiver operating characteristic (ROC) curve for the urinary type IV collagen concentration was equivalent to that of urinary albumin. It was concluded that urinary type IV collagen concentration determined using this method might be a useful marker for the early detection of diabetic nephropathy.

Immunofluorescence staining of renal biopsy samples in patients with diabetic nephropathy in non-insulin-dependent diabetes mellitus using monoclonal antibody to reduced glycated lysine.

This is the first report on immunofluorescence staining of renal biopsy samples in human diabetic nephropathy (DN) using monoclonal antibodies to reduced glycated lysine. In order to detect the localization of glycated lysine in the mesangial matrix and/or the glomerular basement membrane (GBM), we examined immunofluorescence staining using antibodies against reduced glycated lysine in the glomeruli of 16 patients with DN and ten age-matched patients with diffuse mesangial proliferative glomerulonephritis without IgA deposition (DPGN) as controls. In the early stage of DN, immunofluorescence microscopy revealed the presence of intense staining for reduced glycated lysine in the GBM as well as in part of the tubular basement membrane, but not in the mesangial area. In contrast, immunofluorescence microscopy revealed less staining for glycated lysine in the GBM in the advanced stage of DN, and no reaction with any part of the renal tissue in patients with DPGN. It was concluded that detection of reduced glycated lysine in GBM in the early stage of DN might be associated with the initial pathogenesis of this disease.

Intraglomerular C3 synthesis in human kidney detected by in situ hybridization.

Complements 3 and 4 are known to be synthesized in diseased renal tissue and the mRNA of these complements has been demonstrated, using polymerase chain reaction, in renal biopsies from nephritic patients. However, the types of cells producing the complements in intact renal tissue have not been defined. To identify the renal cellular components involved in complement synthesis, we analyzed the expression of C3 mRNA in renal tissues from patients with immune-complex glomerulonephritis by a high-resolution in situ hybridization using digoxigenin-labeled oligonucleotide. Renal tissues from 15 patients with immunoglobulin (Ig) A nephropathy (IgAN), five with lupus nephritis (LN), and five with minimal change nephrotic syndrome (MCNS) were examined. Uninvolved portions of surgically removed kidney with tumors served as normal controls. C3 mRNA was detected in mesangial cells, glomerular epithelial cells, and Bowman's capsule in IgAN and LN. In the interstitium, some tubules and some infiltrating mononuclear cells were positively stained for C3 mRNA. C3 mRNA was not detected in MCNS and control tissues. Our results confirm that the glomerular resident cells can synthesize C3 in immune-mediated glomerulonephritis and suggest that locally synthesized complement may be involved in tissue injury in glomerulonephritis.

Measurement of soluble thrombomodulin in sera from various clinical stages of diabetic nephropathy.

The levels of soluble thrombomodulin (TM) in serum samples were measured by one-step sandwich enzyme immunoassay. The aim of the present study was to determine if levels of soluble TM in sera might correlate with disease activity in patients with diabetic nephropathy. Three hundred and twenty patients with diabetic nephropathy were examined. Patients with diabetic retinopathy were excluded from the present study. This study showed an increase of soluble TM levels in sera from patients with diabetic nephropathy. The levels of soluble TM in sera from the macroalbuminuric stage with renal dysfunction were significantly increased compared with those from the normo-, micro-, or macroalbuminuric stage of diabetic nephropathy without renal dysfunction. The increase of soluble TM in sera paralleled levels of urinary albumin, blood urea nitrogen (BUN), s-creatinine (Cr), and duration of noninsulin-dependent diabetes mellitus (NIDDM). Furthermore, a decrease of TM staining in the glomerular capillary walls was observed in both microalbuminuric and macroalbuminuric stages by immunofluorescence. It appears that the measurement of soluble TM in sera is useful in evaluating the degree of glomerular endothelial injuries in patients with diabetic nephropathy.

Localization of glycated proteins in the glomeruli of patients with diabetic nephropathy.

Glycation of proteins is regarded as one of the major causes of the development and progression of diabetic nephropathy. Based on the numerous reports on experimental models and on our own newly developed techniques, we planned to localize Amadori products and advanced glycation end-products (AGEs), as well as the mRNA expression of cytokines, enzymes and their inhibitors, which are responsible for the expansion of the mesangial areas of the glomeruli. Ten patients with diabetic nephropathy were examined. Patients with immunoglobulin (Ig) A nephropathy and normal portions of the surgically removed kidneys served as controls. Amadori products and AGEs in biopsy specimens were stained by specific monoclonal antibodies, and mRNA expression of the above substances was detected by in situ hybridization. There was a parallel progression in the degree of staining with anti-Amadori product antibody or anti-AGE antibody with the severity of tissue damage in patients with diabetic nephropathy. Patients with IgA nephropathy and normal renal tissues did not show any positive staining with these antibodies. The expression of transforming growth factor beta 1, stromelysin and tissue inhibitor of matrix proteinase 1 in the glomeruli was decreased in diabetic patients with advanced tissue damage, but they were progressively expressed in the advanced stage of IgA nephropathy. It is concluded that Amadori products and of AGEs were formed in parallel in diabetic kidneys. The decrease in the expression of the cytokine and enzymes might be due to altered protein formation associated with glycation.

In situ hybridization of interleukin 6 in diabetic nephropathy.

Increased mesangial expansion is one of the most characteristic histological changes in diabetic nephropathy (DN). Although the pathogenesis of DN remains unclear, recent studies associate interleukin (IL) 6 with mesangial proliferative glomerulonephritis. To elucidate the expression and localization of IL-6 mRNA in renal tissues of patients with DN, a high-resolution in situ hybridization using digoxigenin-labeled oligonucleotide was performed. Patients were divided into three groups based on light microscopy findings: mild (group 1), moderate (group 2), and severe (group 3) mesangial expansion. The relationship between the expression of IL-6 mRNA and the degree of glomerular mesangial expansion in DN was examined. Individual cells positive for IL-6 mRNA were observed in glomeruli. These cells were mesangial cells, glomerular epithelial cells, and Bowman's capsule. The signal intensity was strongest in tissues from group 2 but was weak in those from groups 1 and 3. Most cells in the area of mesangial proliferation were strongly stained for IL-6 mRNA, and few positive cells were found in the Kimmelstiel-Wilson nodular lesion. In the interstitium, some tubules, particularly atrophic tubules, and some infiltrating cells were positively stained for IL-6 mRNA. The interstitial expression of IL-6 mRNA correlated significantly with the degree of interstitial injury and was remarkable in tissues from groups 2 and 3. We conclude that IL-6 mRNA is expressed by glomerular resident cells and interstitial cells in the renal tissue of patients with DN and that its expression may be associated with mesangial proliferation and may be involved in the tissue injury of DN.

Urinary albumin fragments as a new clinical parameter for the early detection of diabetic nephropathy.

Urinary albumin fragments (uAF) from patients with NIDDM were analyzed as a possible factor in the early discovery of diabetic nephropathy before emergence of microalbuminuria. SDS-PAGE and immunoblot assay were employed for detection of uAF. Samples from 252 patients with NIDDM, 158 patients with non-diabetic diseases, and 48 healthy volunteers were examined; uAF were detected in 139 (55.2%), 94 (59.5%), only one (2.1%), respectively. In diabetic patients with normoalbuminuria, uAF were detected in 48 out of 159 cases (30.2%). Two years after the initial study, 3 of the 17 diabetic patients (17.6%) with normoalbuminuria and uAF showed micro- or macroalbuminuria. It was concluded that detection of uAF might be useful for the early detection of diabetic nephropathy in NIDDM.

Differential distribution of type IV collagen chains in patients with diabetic nephropathy in non-insulin-dependent diabetes mellitus.

Thickening of the glomerular basement membrane (GBM) and expansion of the mesangial matrix are hallmarks of human diabetic nephropathy. Renal tissues from 15 patients with type II (non-insulin-dependent) diabetes (NIDDM) were studied by immunofluorescence (IF) and immunogold electron microscopy (IEM) for the distribution of 2 type IV collagen peptides [alpha 3(IV) noncollagenous (NC) domain and alpha 4(IV) NC domain] and 2 classical type IV collagen chains [alpha 1(IV) NC domain and alpha 2(IV) domain]. There was intense staining for alpha 3(IV) NC and alpha 4(IV) NC domain in the GBM but not in the mesangial matrix of patients with overt diabetic nephropathy. In contrast, staining with antibodies to alpha 1(IV) NC and alpha 2(IV) NC domain reacted with mesangial matrix but was significantly decreased in the GBM in the patients with overt diabetic nephropathy. IEM confirmed the IF findings. These data suggest that expansion of the mesangial matrix and thickening of GBM in NIDDM involves separate and distinct type IV collagen components and that the site-specific matrix alterations in NIDDM and type I (insulin-dependent) diabetes are parallel.