Value of urinary excretion of microalbumin in predicting glomerular lesions in children with isolated microscopic hematuria

Urinary microalbumin excretion was assessed in 76 children with asymptomatic microscopic hematuria in whom the presence of proteinuria, hypertension, reduced renal function, hypercalciuria, urinary tract infection or structural abnormality of the urinary tract had been excluded. All children underwent a percutaneous kidney biopsy to determine whether microalbumin excretion can be used as a marker to predict the source of hematuria. Microalbumin excretion was considered normal if the urinary ratio of microalbumin to creatinine (MA/Cr ug/mg) was 30. Twenty-two (29%) had microalbuminuria (MA/Cr 96±30 ug/mg) and 54 (71%) had normal albumin excretion (MA/Cr 13±2 ug/mg). Of those with normoalbuminuria, 38 (70%) had normal renal tissue, 15 (28%) thin glomerular basement membrane (TGBM) disease and 1 (2%) IgA nephropathy. In contrast, 20 (91%) of those with microalbuminuria had IgA nephropathy and 2 (9%) had TGBM disease. The mean urinary MA/Cr ratio for all IgA children was 89±32 ug/mg higher compared with a value for the children with TGBM disease (14 ±3 ug/mg, P <0.001) or children whose renal biopsy appeared normal (11±2 ug/mg, P <0.001). Statistical analysis revealed no significant differences between the mean MA/Cr ug/mg ratio for children with TGBM disease and those with normal glomerular findings. Fourteen of the 20 children with IgA nephropathy who also had microalbuminuria were treated with an angiotensin-converting enzyme (ACE) inhibitor. Over a mean follow-up of 51 months, none developed overt proteinuia; hematuria resolved and microalbuminuria returned to normal in eight (57%) during therapy with the ACE-inhibitor. In contrast, hematuria persisted and prtoteinuria developed in the other untreated children. None of the children with TGBM disease developed overt proteinuria after a mean of 51 months. Hematuria was persistent in children with TGBM disease, but often resolved in those whose biopsies were completely normal. These data suggest that determination of urinary microalbumin excretion is warranted in the routine examination of children with isolated microscopic hematuria. Routine screening for microalbuminuria may help to identify a subgroup of patients with IgA nephropathy who are at high risk for progressive kidney disease and need more intensive therapy and closer follow-up.     

Evaluating the clinical course and prognostic factors of posttransplantation immunoglobulin A nephropathy

INTRODUCTION: Previous reports have suggested that posttransplantation immunoglobulin (Ig) A nephropathy displays a relatively benign course, hardly ever affecting graft function. However, more recent studies with longer follow-up have shown that posttransplantation IgA nephropathy may be a significant contributor to graft loss. Additionally, there may be other clinical or pathological factors that affect long-term graft outcome. We retrospectively analyzed 30 kidney transplant recipients with biopsy-proven IgA nephropathy in their allografts to determine the clinical course and prognostic factors in posttransplantation IgA nephropathy. The median duration of follow-up was 36 months (range, 1 month-17 years). The median onset of IgA nephropathy was 33.6 months posttransplantation (range, 5 days-103 months). The most common presentation was an abnormal urine examination (96.6%). Fifteen (50%) displayed microscopic hematuria with proteinuria more than 1 g/d. Fifteen patients (50%) lost their grafts at a median time of 24 months after the onset of disease (range, 1-93 months). Allograft loss was associated with a high serum creatinine level at the time of diagnosis (3.68 +/- 2.23 vs 1.79 +/- 0.34 mg/dL; P = .006), a greater level of proteinuria at the time of diagnosis (2.43 +/- 0.76 vs 1.29 +/- 1.07 g/d; P = .003), and more than 50% extracapillary proliferation (P = .05). Fibrinoid necrosis on allograft pathology impacted 1-year allograft survival (P = .025). CONCLUSION: Posttransplantation IgA nephropathy worsens allograft outcomes among patients with increased serum creatinine level or significant proteinuria at presentation or significant glomerular inflammation and/or tubulointerstitial damage.     

Treatment of IgA nephropathy in children: efficacy of alternate-day oral prednisone

We have previously reported our experience with the use of alternate-day prednisone in the treatment of 6 patients with IgA nephropathy who have clinical or pathological risk factors for disease progression. We have now treated a total of 13 patients and followed them from 4 to 10 years. Patients received an alternate-morning dose of prednisone for 2–4 years. Dosage began at 60 mg/m² for 3 month, was reduced to 30 mg/m² by 1 year and 15 mg/m² by 2 years. At last observation, urinary protein excretion was normal in 12 patients and no patient had hematuria. Twelve patients had normal estimated glomerular filtration rate (GFR) and one had renal insufficiency (GFR=38 ml/min per 1.73 m²). A renal biopsy was performed in 11 patients after 2 years of treatment. Activity score decreased from 5.2 to 4.3 (P=0.03) and chronicity score increased from 2.2 to 2.8 (P=0.12). There were no complications of treatment. When compared with a historical group, the treated patients had a significant improvement in urinalysis (P<0.00001) and preservation of normal GFR (P=0.03). We conclude that alternate-day prednisone therapy may benefit patients with IgA nephropathy. A large prospective controlled trial is needed.     

IgA肾病患者高血压的相关因素分析

目的探讨IgA肾病患者高血压的相关因素。方法经肾脏活体组织检查确诊的IgA肾病患者120例,采用单因素和多因素Logistic回归分析IgA肾病患者高血压发生的相关因素。结果120例IgA肾病患者中伴有高血压患者39例（占32．5％）。单因素分析发现,24h尿蛋白定量≥2．0g、尿素氮（BUN）≥8mmol／L、血肌酐（SCr）≥133μmol／L、肾小球率过滤（GFR）〈60ml·min^-1·（1．73m^2）^-1、高尿酸血症、贫血、肾小球慢性病变指数≥4分、肾间质炎症细胞侵润〉25％、肾小管萎缩和问质纤维化〉25％、肾小动脉管壁增厚、Lee分级Ⅳ～Ⅴ级与IgA肾病患者高血压相关。多因素Logistic回归结果显示,蛋白尿程度、GFR水平为IgA肾病高血压发生的独立危险因素。结论32．5％的IgA肾病患者伴有高血压,蛋白尿程度、GFR水平是高血压的独立危险因素。     

Beneficial Effects of Tonsillectomy for Mesangial Immunoglobulin A (IgA) Deposition and Clinical Outcome in Five Kidney Transplant Patients With Recurrent IgA Nephropathy: Case Report

Introduction

Tonsillectomy has been applied for recurrent immunoglobulin (Ig)A nephropathy (IgAN) in kidney transplantation recipients, but allograft histologic changes after this treatment remain unclear.

Methods

Five patients with recurrent IgAN underwent tonsillectomy for persistent proteinuria (average, 397.2 mg/d; >6 months). Six repeated biopsies were taken 33.8 ± 17.1 months after treatment. Glomerular IgA deposition was detected by immunofluorescence staining on frozen tissue. Histologic and clinical data have been collected.

Results

An average of 11.2 months (range, 6–20) after tonsillectomy, proteinuria decreased to 60.8 ± 49.3 mg/d. Serum creatinine (SCr) slightly decreased (1.33 ± 0.31 before vs 1.24 ± 0.29 after treatment; P > .05). In 5 of the 6 repeated biopsy samples month after tonsillectomy, there was decreased mesangial IgA deposition. Glomerular crescent and endothelial proliferation were no longer found, although there was increased focal sclerosis and adhesion. After tonsillectomy, there were increased interstitial fibrosis and tubular atrophy, with no significant differences in Banff scores.

Conclusions

Tonsillectomy can reverse not only persistent proteinuria, but also mesangial IgA deposition in patients with recurrent IgAN. Tonsillectomy may have both favorable clinical and histologic effects in recurrent IgAN after kidney transplantation.     

Development of IgA nephritis following cat scratch disease in a 13-year-old boy

We describe a 13-year-old boy who presented with hematuria and intermittent low-grade proteinuria at the time when he was diagnosed with cat scratch disease. Two months before presentation, he had a negative urinalysis during a routine physical evaluation. He continued to have microscopic hematuria for the next 6 months, when he developed gross hematuria and recurrence of low-grade proteinuria. The renal biopsy showed evidence of mild/moderate IgA nephropathy. We speculate that the immunological changes associated with cat scratch disease in this patient may have triggered the development of IgA nephropathy. A history or serological evidence of infection with Bartonella henselae may need to be sought in patients presenting with IgA nephritis.     

Proposal of remission criteria for IgA nephropathy

Background

The remission criteria of immunoglobulin A (IgA) nephropathy have varied depending on the clinical study. Therefore, nephrologists cannot make a uniform assessment of treatment outcomes and the standardization of explanations of the condition is difficult in patients with IgA nephropathy. This study aims to propose clinical remission criteria for IgA nephropathy based on a nationwide opinion survey in Japan regarding IgA nephropathy remission/relapse.

Method

This nationwide survey was sent to 312 teaching facilities of the Japanese Society of Nephrology by Progressive Renal Disease Research, Research on Intractable Disease, from the Ministry of Health, Labour and Welfare of Japan.

Results

Valid answers were obtained from 193 facilities (61.9 %) (136 internal medicine facilities and 57 pediatric facilities), of which 134 (69.4 %) thought that both hematuria and proteinuria should be used in the remission standards. Approximately half of the survey respondents shared the opinion on standards of negative results for hematuria and proteinuria and the duration and frequency of these conditions.

Conclusion

In this paper, we propose a standardized set of criteria for defining IgA nephropathy remission: three consecutive negative results over a 6-month period in urinary occult blood tests; urinary sediment red blood cell count of <5/high-power field (hematuria remission); and urinary protein of <0.3 g/day (g/g Cr; proteinuria remission). Clinical remission is defined as cases with both hematuria and proteinuria remission. These consensus-based remission criteria should be verified in future studies. In the meantime, they may be useful in predicting therapeutic outcome in cases of IgA nephropathy.     

The effectiveness of steroid therapy for patients with advanced IgA nephropathy and impaired renal function

Background Recent studies have shown that steroid therapy is effective for IgA nephropathy (IgAN) in patients with moderate proteinuria and active histological findings. However, the effectiveness of steroid therapy has not been determined yet in patients with advanced IgAN and impaired renal function.Methods Sixty IgAN patients whose creatinine clearance was under 70ml/min at the time of renal biopsy were studied retrospectively. The patients were divided into two groups according to treatment: a steroid group (n = 20) and a nonsteroid group (n = 40). The mean age was 39.6 ± 14.9 years in the steroid group and 40.6 ± 10.9 years in the nonsteroid group. The mean follow-up period was 4.5 ± 2.2 years in the steroid group and 4.6 ± 2.4 years in the nonsteroid group. Patients with high proteinuria and high histological activity were treated with prednisolone. Clinical and histological findings before treatment and the outcome after treatment were analyzed.Results In the retrospective analysis, the amount of urinary protein excretion before treatment tended to be higher in the steroid group than in the nonsteroid group, but was not significantly different (2.33 ± 1.54 vs 1.39 ± 1.87g/day). Histologically, the percentage of patients with crescent formation, especially that of cellular or fibrocellular crescents, was significantly higher in the steroid group than in the nonsteroid group (17.2 ± 15.9% vs 2.3 ± 4.5%; P < 0.0001). The grades of mesangial cell proliferation (1.65 ± 0.55 vs 1.21 ± 0.47; P = 0.002) and mesangial matrix increase (1.88 ± 0.64 and 1.41 ± 0.67; P = 0.01) were higher in the steroid group than in the nonsteroid group. In the evaluation of the outcome after treatment, the amount of urinary protein excretion at 1 year after treatment had significantly decreased in the steroid group (before treatment, 2.33 ± 1.54g/day; at 1 year, 1.02 ± 0.98g/day; P = 0.003), but the amount remained unchanged in the nonsteroid group (before treatment, 1.39 ± 1.87g/day; at 1 year, 1.28 ± 2.19g/day). The levels of serum creatinine before treatment and at 1 year after treatment were not changed in either of the groups, however, in the nonsteroid group, the level at the final observation was significantly higher than the level before treatment (2.51 ± 3.43 vs 1.27 ± 0.33mg/dl; P = 0.0219).Conclusions In the present study, in advanced IgAN patients whose creatinine clearance was under 70ml/min, steroid therapy effectively reduced the amount of proteinuria and maintained the serum creatinine level, if the treatment was selectively applied to patients with a moderate amount of proteinuria and active glomerular lesions such as cellular and fibrocellular crescents, and mesangial cell proliferation.     

Urinary liver-type fatty acid-binding protein: discrimination between IgA nephropathy and thin basement membrane nephropathy

BACKGROUND: Microscopic hematuria without proteinuria is a common clinical finding in cases of immunoglobulin A (IgA) nephropathy and of thin basement membrane nephropathy. Liver-type fatty acid-binding protein (L-FABP) is expressed in renal proximal tubules and is reported to be a useful marker of the progression of chronic glomerulonephritis. AIM: To assess urinary L-FABP levels for differential diagnosis in patients with microscopic hematuria but without proteinuria. METHODS: This was a multi-center retrospective study. Thirty adult patients who underwent renal biopsy for microscopic hematuria and 20 healthy adult volunteers were included in this study. Urinary L-FABP levels were measured by enzyme-linked immunosorbent assay and compared, particularly between those diagnosed with IgA nephropathy and those diagnosed with thin basement membrane nephropathy. RESULTS: Twelve (40%) patients had IgA nephropathy, 6 (20%) had thin basement membrane nephropathy and 12 (40%) had normal biopsy findings. The urinary L-FABP level was significantly higher in patients with IgA nephropathy (38.4 +/- 26.8 microg/g Cr) than in healthy subjects (5.8 +/- 4.0 microg/g Cr) (p < 0.01); however, the level in patients with thin basement membrane nephropathy or normal biopsy results was comparable to that in healthy subjects. Follow-up data were available for 11 of the 12 patients with IgA nephropathy who initially had no proteinuria. After 24 months, 4 of the 11 were found to have proteinuria, and the urinary L-FABP level had increased from 40.6 +/- 30.5 microg/g Cr to 58.8 +/- 40.5 microg/g Cr (p < 0.01). CONCLUSIONS: Our data suggest that the urinary L-FABP level can be used to discriminate between IgA nephropathy and thin basement membrane nephropathy in patients with microscopic hematuria.     

益气滋肾颗粒控制IgA肾病血尿的多中心临床疗效评价

目的:客观评价益气滋肾颗粒治疗IgA肾病血尿(气阴两虚证)的临床疗效.方法:通过多中心、随机、平行对照的临床试验,观察益气滋肾颗粒对IgA肾病血尿、蛋白尿、肾功能、中医证候的干预效果,观察临床病例211例,治疗组109例,对照组102例.结果:治疗组IgA肾病患者血尿恢复正常的比率,与治疗时间呈正相关性.治疗12周后,血尿恢复正常率、改善1级以上的比率,治疗组显著优于对照组.治疗12周时,治疗组蛋白尿的完全缓解率35%,减少50%者为23.33%,尿蛋白定量平均下降52.54%,明显优于对照组.治疗8周、12周时治疗组中医症状积分减少优于对照组,具有统计学差异.结论:益气滋肾颗粒在控制IgA肾病血尿、减少蛋白尿、改善患者症状等方面具有良好的作用.     

The efficacy of tonsillectomy on clinical remission and relapse in patients with IgA nephropathy: a randomized controlled trial

Background The efficacy of tonsillectomy in immunoglobulin A nephropathy (IgAN) remains controversial. The aim of the study was to conduct a randomized controlled trial to evaluate the effect of tonsillectomy in patients with IgAN. Methods We randomly selected 98 patients with biopsy-proven IgA nephropathy and randomly allocated to receive tonsillectomy combined with drug therapy (Group A) or drug therapy alone (Group B). The participating patients were entered into a 4-year single-center study. Remission and relapse rate were calculated for hematuria and proteinuria using the Kaplan–Meier method. Results No differences were found between the two groups in their baseline clinical and histological characteristics. Patients with tonsillectomy exhibited considerable improvement in the following aspects compared to those patients who did not undergo tonsillectomy: time to reach first remission (3.1 vs. 24.9 months, p?p?p?p?p?=?0.0047) for hematuria and (23.5 vs. 10.5 months, p?=?0.0012) for proteinuria, as well as lower relapse rate for hematuria and proteinuria in Group A. Conclusion Our clinical data demonstrated that tonsillectomy could be beneficial for IgAN patients, particularly by contributing to faster and longer remission, as well as reducing the frequency of possible future relapses.     

Clinicopathological features and the prognosis of IgA nephropathy in Japanese children on long-term observation

AIMS: Clinicopathological features were investigated to clarify the ultimate prognosis and prognostic indicators for patients with IgA nephropathy in Japanese children. METHODS: We evaluated the outcomes of 181 patients in whom IgA nephropathy was diagnosed before the age of 15 years since September 1979 and followed-up at least for three years with regard to clinical data at the onset of symptoms and renal histologic data. RESULTS: After mean follow-up of 7.3 years from onset, 91 patients of 181 (50.3%) were in clinical remission at the last examination, 24 (13.2%) had isolated hematuria, 59 (32.6%) had hematuria and proteinuria. Eighteen of 59 (9.9%) had proteinuria more than 1 g per 24 hours. Hypertension was observed in 12 cases and 7 (3.9%) developed end-stage renal disease. Except 7, no patient had reduced renal function and elevated serum creatinine at the final follow-up. Predicted renal survival rate from onset was 92.3% at 10 years and 89.1% at 20 years. In multivariable analysis, age at onset and chronic changes of tubulointerstitium were associated with poor outcome. CONCLUSIONS: Of 181 children with IgA nephropathy, 50% regressed, remaining 46% had hematuria and/or proteinuria and 4% of patients lapsed into end-stage renal disease. Our results indicate that childhood IgA nephropathy has a benign course and the risk for end-stage renal disease is lower than that of adults. Age at onset and tubulointerstitial lesions were the strong predictors of a progressive course of childhood IgA nephropathy.     

尿激酶联合缬沙坦对IgA肾病尿检异常型的疗效分析

目的小剂量尿激酶联合缬沙坦治疗IgA肾病尿检异常型的临床疗效。方法将60例经肾脏组织活体检查并结合临床诊断为原发性IgA肾病尿检异常的患者,分为尿激酶联合缬沙坦治疗组（治疗组）和单用缬沙坦治疗组（对照组）,每组各30例。比较2组的临床疗效。结果治疗组尿红细胞（RBC）计数与24h尿蛋白定量在第3、6及12个月均较治疗前明显下降（P〈0.05）,而对照组尿RBC计数与24h尿蛋白定量在治疗前后比较虽有下降,但无统计学意义（P〉0.05）。结论通过尿激酶联合缬沙坦治疗,能有效减少IgA肾病尿检异常患者的蛋白尿和镜下血尿。     

Effect of oral camostat mesilate on hematuria and/or proteinuria in children

The effects of camostat mesilate (CM), a derivative of gabexate mesilate developed for oral use, on primary glomerulonephritis (GN) and chance hematuria and/or proteinuria were evaluated. Fourteen patients (6 males, 8 females) with a mean age of 11 years and 3 months (range 4–16 years) were enrolled. Histological and clinical diagnoses of the 14 patients were as follows: IgA nephropathy 3, non-IgA GN 2, and asymptomatic significant microscopic hematuria [more than 100 red blood cells per high-power field (x400)] with or without proteinuria 9. They were consecutively treated with oral CM (100 mg twice a day) when they were confirmed to have continuous significant microscopic hematuria and/or proteinuria after a few months of observational follow-up. Urinary findings were normalized in 10 of the 14 patients (85.7%) between 1 month 1 week and 10 months (mean 4 months) after administration of CM. Hematuria cleared in 11 of 13 patients, and proteinuria disappeared in 4 of 5 patients. The mean duration of CM administration was 21.7±9.1 months (range 4–37 months). At present, 3–12 years after discontinuation of CM therapy, their urinary findings remain normal at 9 years 10 months to 26 years 6 months of age. In conclusion, there appears to be an association between the oral use of CM and reduction in significant microscopic hematuria and/or proteinuria. Oral CM therapy could represent a practical primary care approach to chance hematuria and/or proteinuria in children.     

Prednisolone Co-Administered with Losartan Confers Renoprotection in Patients with IgA Nephropathy

Background.Treatment options for progressive IgA nephropathy are limited. Methods. We performed a small, randomized controlled trial to evaluate the effects of prednisolone (PSL, 30 mg/dL, gradually tapered to 5 mg/dL over two years) plus 50 mg/day of losartan (LST, an angiotensin II receptor blocker) or PSL alone on IgA nephropathy. We separated 38 patients (age, 33 ± 11 years; creatinine clearance, 103 ± 31 mL/min; proteinuria, 1.6 ± 0.5 g/day) into two groups that were treated with either PSL plus LST or PSL alone, and compared the proteinuria and creatinine clearance after two years. Baseline and histopathological data did not significantly differ between the two groups. Results. Two years of treatment in both groups significantly decreased proteinuria compared with baseline, and PSL plus LST (from 1.6 ± 0.6 to 0.3 ± 0.1 g/day, p < 0.05) was more effective than PSL alone (from 1.6 ± 0.3 to 0.5 ± 0.1 g/day, p < 0.05). Creatinine clearance in both groups was similar at the start of study but significantly differed at the end of the study (PSL plus LST, 104.3 ± 36.4 to 100.4 ± 38.9 mL/min; PSL alone, 103.4 ± 28.5 to 84.8 ± 34.3 mL/min, p < 0.05). Conclusions. Combined therapy with PSL plus LST appears to be more effective than PSL alone in reducing proteinuria and protecting renal function in patients with IgA nephropathy.     

Effect of corticosteroid therapy on the progression of IgA nephropathy with moderate proteinuria

Background. In patients with heavy proteinuria, corticosteroid therapy has been shown to have favorable effects on the progression of IgA nephropathy. However, the efficacy of corticosteroids on the progression of IgA nephropathy with moderate proteinuria is still controversial. Methods. We assessed 45 adult (age, 18–50 years) patients with moderate proteinuria (0.5–2.0g daily) and preserved renal function, (serum creatinine concentration, 106µmol/l) who were diagnosed as having primary IgA nephropathy between December 1993 and July 1998. Twenty-three of the patients were treated with corticosteroids (steroid group), and the remaining 22 patients had no steroid treatment (control group). All patients were followed up for more than 3 years. Results. There were no differences in baseline characteristics between the two groups, except for proteinuria. In the steroid group, urinary protein excretion was significantly higher than that in the control group. During the follow-up period, urinary protein excretion was not changed in the control group. On the other hand, in the steroid group, mean urinary protein excretion decreased significantly. Seven patients in the control group and 2 patients in the steroid group reached the endpoint, which was defined as a 50% increase in serum creatinine concentration from baseline. Renal survival curves were significantly different between the two groups. A second biopsy was performed in 20 patients who received steroid therapy. Mesangial cell proliferation, mesangial matrix increase, and cellular crescents were significantly reduced in the second compared with the first biopsy specimens. Conclusions. Steroid therapy is effective in reducing the progression of IgA nephropathy with moderate proteinuria.     

强直性脊柱炎相关IgA肾病临床病理分析

目的了解强直性脊柱炎（AS）相关IgA肾病的临床病理特点。方法自1997年1月至2006年12月10年间在北京协和医院接受肾活检确诊为IgA肾病的AS患者10例，回顾性分析其临床及病理特点。结果男性9例，女性l例，平均年龄（28．6＋6．8）岁（16～53岁）。4例患者表现为无症状镜下血尿；6例表现反复血尿合并蛋白尿，其中2例有发作性肉眼血尿。平均尿蛋白量（24h）为（1．56±1．53）g（0．02-5．26g）。2例患者有血压升高。所有患者的血肌酐水平均在正常范围。光镜下，8例患者呈轻度系膜细胞增生，IgA肾病Lee氏分级均为Ⅰ或Ⅱ级；另外2例呈中重度系膜增生性改变，IgA肾病Lee氏分级分别为Ⅲ级和Ⅵ级。结论AS相关IgA肾病临床表现为隐匿性肾炎或慢性肾小球肾炎，病理改变以轻度系膜增生为主。     

Steroid pulse therapy combined with tonsillectomy in a patient with IgA nephropathy complicated with tuberculous pleurisy

We report a case of IgA nephropathy with tuberculous pleurisy that was treated with steroid pulse therapy combined with tonsillectomy. A 27-year-old female was referred to our hospital because of hematuria and proteinuria. Her urinalysis showed mild proteinuria (0.7 to 0.9 g/day) with dysmorphic red blood cells and cellular casts. Her serum creatinine level was within the normal range. Renal biopsy specimens revealed mild mesangial proliferation with cellular crescent and adhesion of glomeruli to the Bowman's capsule. Tubulointerstitial changes including mononuclear cell infiltration and tubular atrophy were also observed. Immunohistochemical staining of IgA and C3 was detected in the mesangial area, leading to the diagnosis of IgA nephropathy. She had a past history of tuberculous pleurisy at 13 years of age and had taken antituberculosis drug for one and a half year. Although treatment with angiotensin receptor antagonist was started, the amount of proteinuria was not changed. Steroid pulse therapy with tonsillectomy followed by oral prednisolone 20 mg/day was conducted. Proteinuria and hematuria gradually decreased. Her respiratory status and chest X-ray had been closely followed up by her respiratory physician. After one and a half years of treatment with low-dose prednisolone, her urinalysis became almost normal. Recurrence of tuberculosis was not observed during the follow-up period. The successful outcome of this case encouraged us to treat IgA nephropathy with a past history of tuberculosis using interventions including steroid pulse therapy.     

Prognosis of asymptomatic hematuria and/or proteinuria in men. High prevalence of IgA nephropathy among proteinuric patients found in mass screening

AIM: To elucidate prognosis and prevalence of chronic renal diseases among proteinuric and/or hematuric subjects found in mass screening, a long-term follow-up study (6.35 years, range 1.03-14.6 years) was conducted on Japanese working men. METHODS: A total of 772 subjects selected from 50,501 Japanese men aged 15-62 years were found to have asymptomatic hematuria (n = 404), concomitant hematuria and proteinuria (n = 155), and proteinuria (n = 213) during their annual urine examination and five consecutive urinalyses. RESULTS: Hematuria patients showed significant improvements in urinary abnormalities as compared with both hematuria/proteinuria and proteinuria patients. Both hematuria/proteinuria patients with normotension and hematuria/proteinuria patients aged under 40 years showed significant improvements. During the follow-up period, 9.5% of the hematuria patients became hematuric/proteinuric. Hematuria/proteinuria patients had the highest risk of developing renal insufficiency. The presence of hypertension at detection of urinary abnormalities did not affect the renal function; however, if proteinuria appeared after the age of 40 years, these patients had a higher risk of developing renal insufficiency. The incidence of IgA nephropathy in the present subjects was as high as 143 cases per 1 million per year. CONCLUSION: Detailed follow-up and definitive diagnosis of asymptomatic urinary abnormalities may raise the prevalence of IgA nephropathy worldwide.     

Profiling proteinuria in pediatric patients

This study was designed to characterize proteinuria in children with kidney disease. Random urine samples from 250 pediatric patients were examined by quantitative measures of total protein (pr), albumin (Alb), and creatinine (cr). Patient diagnoses were subjectively categorized as “Glomerular” (GD) or “Tubulo-interstitial” disease (TD) in origin. Proteinuria was quantitated by the random urine protein-to-creatinine (Upr/cr) ratio, and glomerular proteinuria was assessed as the albumin-to-creatinine ratio (Ualb/cr) and percentage albuminuria (%Alb=Alb/pr*100). The non-albumin fraction (1−Alb/pr) includes low-molecular-weight proteins and micro- and macroglobulins. Of the 250 patients, 112 (45%) had GD and 138 (55%) had TD. Both proteinuria and albuminuria correlated with a decline in glomerular filtration rate (GFR) (r=−0.4; p<0.0001). Those with GD averaged significantly greater %Alb than those with TD at all levels of proteinuria (p<0.0001). With loss in GFR, %Alb increased significantly in patients with TD (18±13 to 47±30%; p<0.001) and GD (56±26 to 74±15%; p<0.01), respectively. The %Alb at all levels of GFR averaged <50% in those with TD and >50% in those with GD. In conclusion, random Ualb/cr, Upr/cr, and %Alb provide a simple and inexpensive assessment of proteinuria and may profile renal disease activity and response to therapy in pediatric patients.