Insight into the Interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in IgA Vasculitis (IgAV)

The pathogenesis of IgAV, the most common systemic vasculitis in childhood, appears to be complex and requires further elucidation. We aimed to investigate the potential role of galactose-deficient immunoglobulin A1 (Gd-IgA1), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE) and protocadherin 1 (PCDH1) in the pathogenesis of IgAV. Our prospective study enrolled 86 patients with IgAV and 70 controls. HMGB1, RAGE, Gd-IgA1 and PCDH1 in serum and urine were determined by the enzyme-linked immunosorbent assay (ELISA) method at the onset of the disease and after a six-month interval in patients and once in the control group. Serum concentrations of HMGB1, RAGE and PCDH1 and urinary concentrations of HMGB1, RAGE, Gd-IgA1 and PCDH1 were significantly higher in patients with IgAV than in the control group (p < 0.001). Concentrations of HMGB1 (5573 pg/mL vs. 3477 pg/mL vs. 1088 pg/mL, p < 0.001) and RAGE (309 pg/mL vs. 302.4 pg/mL vs. 201.3 pg/mL, p = 0.012) in the serum of patients remained significantly elevated when the disease onset was compared with the six-month follow-up interval, and thus could be a potential marker of disease activity. Urinary concentration of HMGB1 measured in the follow-up period was higher in patients with nephritis compared to IgAV without nephritis (270.9 (146.7-542.7) ng/mmol vs. 133.2 (85.9-318.6) ng/mmol, p = 0.049) and significantly positively correlated with the urine albumine to creatinine ratio (τ = 0.184, p < 0.05), the number of erythrocytes in urine samples (τ = 0.193, p < 0.05) and with the outcome of nephritis (τ = 0.287, p < 0.05); therefore, HMGB1 could be a potential tool for monitoring patients with IgAV who develop nephritis. Taken together, our results imply a possible interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in the development of IgAV. The identification of sensitive biomarkers in IgAV may provide disease prevention and future therapeutics.

Clinical outcomes in children with Henoch-Schönlein purpura nephritis without crescents

BACKGROUND

Henoch-Schönlein purpura is the most common vasculitis in children. Its long-term prognosis depends on renal involvement. The management of Henoch-Schönlein purpura nephritis (HSPN) remains controversial. This study reports the prognosis of children with HSPN presenting with class 2 International Study of Kidney Disease in Children (ISKDC) nephritis.

METHODS

All children with HSPN class 2 diagnosed between 1995 and 2015 in four pediatric nephrology centers were included, and clinical and biological data were collected from the medical files. The primary endpoint was proteinuria remission defined as a proteinuria <200 mg/L.

RESULTS

Ninety-two children were included in the study with a median follow-up of 36 (6-120) months; 28% had nephrotic syndrome, 31% proteinuria >3 g/L, 52% proteinuria between 1 and 3 g/L, and 18% proteinuria <1 g/L. Forty-seven percent of patients received orally treatment with steroids alone, 37% received methylprednisolone pulses followed by steroids orally, 18% received no steroids. Although 85% reached remission during follow-up, 12% did not maintain complete remission over time so that only 75% remained in complete remission by the end of the follow-up. Univariate analysis found a higher likelihood of remission in patients with higher proteinuria at disease onset (p = 0.009). This trend was not found in the multivariate analysis after adjusting for treatments, as patients with higher proteinuria were most often treated with steroids.

CONCLUSION

Our study shows that one fourth of patients with HSPN class 2 remain proteinuric and thus carry the risk of developing chronic kidney disease over the long term. This finding, together with the better outcome of patients treated with steroids, is in favor of using high-dose steroids orally or IV in these patients.

24h Urinary Protein Levels and Urine Protein/Creatinine Ratios Could Probably Forecast the Pathological Classification of HSPN

This study aimed to assess the relevance of laboratory tests in Henoch-Schönlein purpura nephritis (HSPN) classification, and determine accurate classification factors. This prospective study included 694 HSPN patients who underwent ultrasound-guided percutaneous renal biopsy (PRB). Renal specimens were scored according to International Study of Kidney Disease in Children (ISKDC) classification. Meanwhile, blood samples were immediately collected for laboratory examination. The associations between laboratory parameters and HSPN classification were assessed. Significant differences in levels of serum Th1/Th2 cytokines, immunoglobulins, T-lymphocyte subsets, complement, and coagulation markers were obtained between HSPN patients and healthy children. Interestingly, 24h urinary protein (24h-UPRO) levels and urine protein/urine creatinine ratios could determine HPSN grade IIb, IIIa, and IIIb incidences, with areas under ROC curve of 0.767 and 0.731, respectively. At 24h-UPRO >580.35mg/L, prediction sensitivity and specificity were 75.2% and 70.0%, respectively. These values became 53.0% and 82.3%, respectively, with 24h-UPRO exceeding 1006.25mg/L. At urine protein/urine creatinine > 0.97, prediction sensitivity and specificity were 65.5% and 67.2%, respectively, values that became 57.4% and 80.0%, respectively, at ratios exceeding 1.2. Cell and humoral immunity, coagulation and fibrinolytic systems are all involved in the pathogenesis of HSPN, and type I hypersensitivity may be the disease trigger of HSPN. 24h-UPRO levels and urine protein/creatinine ratios could probably forecast the pathological classification of HSPN.

Elevated urinary levels of cystatin C and neutrophil gelatinase-associated lipocalin in Henoch-Schönlein purpura patients with renal involvement

Henoch-Schönlein purpura (HSP) is a commonest systemic vasculitis in childhood. The long-term prognosis of HSP is determined by the degree of renal involvement. The aim of this study is to search novel clinically applicable biomarkers to evaluate renal involvement in HSP patients. 20 bio-indexes in urine samples were simultaneously screened by antibody array assay. We indicated that urinary levels of cystatin C (Cys C) and neutrophil gelatinase-associated lipocalin (NGAL) in HSP patients with renal involvement were significantly higher than those without renal involvement and healthy controls. Furthermore, ELISA was used to analyze urinary Cys C and NGAL levels in HSP patients with or without renal involvement, atopic dermatitis (AD) patients and healthy controls. Our results demonstrated that urinary Cys C and NGAL levels in HSP patients with renal involvement were significantly elevated, when compared with those without renal involvement, AD patients and control subjects. In addition, by receiver operating characteristic (ROC) curve analysis, we demonstrated that the area under the ROC curve of NGAL (0.789) was larger than that of Cys C (0.692). Taken together, we show firstly that urinary Cys C and NGAL levels is abnormally elevated in HSP patients with renal involvement. We suggest that urinary Cys C and NGAL are novel useful biomarkers of renal involvement in HSP patients.

Soluble transferrin receptor in urine, a new biomarker for IgA nephropathy and Henoch-Schönlein purpura nephritis

OBJECTIVES

IgA nephropathy (IgAN) and Henoch-Schönlein purpura nephritis (HSPN) might represent different ends of a continuous spectrum of glomerular disease. In both conditions, upregulated soluble transferrin receptor (sTfR) might be excreted in urine, which could be a potential biomarker to monitor disease activity and therapeutic response.

METHODS

In this pilot study, 132 Caucasian patients consulting the Nephrology Department at the Ghent University Hospital because of a glomerulopathy and 50 normal controls were included. Urinary sTfR concentrations were determined in concentrated urine using a newly developed latex-enhanced immunonephelometric assay.

RESULTS

Median urinary sTfR concentration was higher in patients with a primary glomerulopathy than in healthy subjects (p<0.0001). More importantly, absolute median levels of urinary sTfR were markedly higher in patients with active IgAN or HSPN [10μg/L, 95% confidence interval (CI): 6-18μg/L] in comparison with those with other morphological types of glomerulopathy (2μg/L, 95%CI: 1-4μg/L) (p<0.0001). A statistically significant difference in urinary sTfR concentration was observed between patients with active IgAN or HSPN and patients who had achieved partial or complete remission (p<0.0001). Multiple regression analysis with urinary sTfR as dependent variable revealed that proteinuria was the main predictor of urinary sTfR concentration (r(2)=0.52, p<0.001).

CONCLUSION

Determination of sTfR in urine is a new and sensitive method for a potential biomarker of IgAN and HSPN.

Henoch schonlein purpura--a 5-year review and proposed pathway

Henoch Schonlein Purpura (HSP) is the commonest systemic vasculitis of childhood typically presenting with a palpable purpuric rash and frequently involving the renal system. We are the first group to clinically assess, critically analyse and subsequently revise a nurse led monitoring pathway for this condition.A cohort of 102 children presenting with HSP to a secondary/tertiary level UK paediatric hospital over a five year period, were monitored using a nurse led care pathway. Using this cohort, the incidence (6.21 cases per 100,000 children per year) and natural disease course of HSP nephritis (46% initial renal inflammation; 9% subsequent renal referral; 1% renal biopsy and immunosuppression) was determined. Older patients were at higher risk of requiring a renal referral (renal referral 12.3 (8.4-13.5) years vs. normal outcome 6.0 (3.7-8.5) years; p<0.01). A normal urinalysis on day 7 had a 97% (confidence interval 90 to 99%) negative predictive value in predicting a normal renal outcome.Using this data and existing literature base, The Alder Hey Henoch Schonlein Purpura Pathway was developed, a revised pathway for the screening of poor renal outcome in HSP. This is based on a six-month monitoring period for all patients presenting with HSP, which importantly prioritises patients according to the urine findings on day 7 and thus intensively monitors those at higher risk of developing nephritis. The pathway could be easily adapted for use in different settings and resources.The introduction of a standardised pathway for the monitoring of HSP will facilitate the implementation of disease registries to further our understanding of the condition and permit future clinical trials.

[Contents of serum Cyst-C and urinary microalbumin in children with Henoch-Schonlein purpura]

OBJECTIVE

To investigate the clinical significance of serum Cyst-C and urinary microalbumin in early renal impairment in children with Henoch-Schonlein purpura (HSP).

METHODS

Forty-eight children with HSP and who had normal serum creatinine level and 31 healthy children were enrolled. Contents of serum Cyst-C and urinary microalbumin were measured using ELISA and immunoturbidimetry, respectively. Urinary routine examination was performed in children with HSP. The contents of serum Cyst-C and urinary microalbumin were re-examined one month after treatment (recovery phase).

RESULTS

The contents of serum Cyst-C (2.24+/- 0.81 mg/L) and urinary microalbumin (20.04+/- 10.32 mg/L) in the HSP group at the acute phase were significantly higher than those in the control (0.85+/- 0.20 and 2.30+/- 1.38 mg/L respectively; P< 0.01). Serum Cyst-C (1.70+/- 0.30 mg/L) and urinary microalbumin contents (13.20+/- 8.16 mg/L) were significantly reduced at the recovery phase compared with those at the acute phase in the HSP group (P< 0.01). The proportion of urinary routine abnormality (33.3%) was significantly lower than that of urinary microalbumin (68.8%) and serum Cyst-C abnormalities (72.9%) in the HSP group (P< 0.01).

CONCLUSIONS

Serum Cyst-C and urinary microalbumin may serve as indexes in the assessment of early renal impairment in children with HSP.

Predictors of outcome in Henoch-Schönlein nephritis in children and adults

BACKGROUND

Factors predictive of renal outcome were investigated in 219 cases of biopsy-proven Henoch-Schönlein purpura nephritis (HSPN); 83 children and 136 adults enrolled in a national study were followed up for up to 27 years (median, 4.5 years).

METHODS

The criterion for defining disease progression was time elapsed until doubling of baseline creatinine level and until dialysis therapy. Age, sex, data at onset (renal function, proteinuria, hematuria, hypertension, and crescents), and data during follow-up (proteinuria and therapy) were tested as covariates.

RESULTS

Multivariate Cox regression analysis indicated the following parameters as independent prognostic predictors: age (adults versus children, relative risk, 3.57; 95% confidence interval, 1.18 to 10.79; P = 0.024 for creatinine level doubling; relative risk, 14.89; 95% confidence interval, 1.72 to 129.07; P = 0.014 for dialysis therapy), sex (females versus males, relative risk, 5.71; 95% confidence interval, 1.67 to 19.55; P = 0.006 for creatinine level doubling; relative risk, 26.03; 95% confidence interval, 2.64 to 256.73; P = 0.005 for dialysis therapy), and mean proteinuria during follow-up (for each 1 g/d of protein increase, relative risk, 1.77; 95% confidence interval, 1.35 to 2.32; P < 0.001 for creatinine level doubling; relative risk, 1.73; 95% confidence interval, 1.18 to 2.52; P = 0.005 for dialysis therapy). Information for mean proteinuria levels during follow-up increased the sensitivity at logistic regression to 62.5%, with dialysis therapy as the end point. No data detected at diagnosis, including renal function impairment, proteinuria, hypertension, and crescentic nephritis (involving > 50% of glomeruli in only 2.6%), were significantly related to functional decline at multivariate Cox.

CONCLUSION

This analysis indicates that, even more than when decreased renal function, severe proteinuria, hypertension, or crescents are present at onset, the risk for progression of HSPN (greater in adults and females) was associated with increasing mean proteinuria levels during follow-up.

Predictive factors for nephritis, relapse, and significant proteinuria in childhood Henoch-Schönlein purpura

OBJECTIVE

To identify predictive factors for nephritis, relapse, and significant proteinuria in childhood Henoch-Schönlein purpura (HSP).

METHODS

Two hundred and six consecutive patients with HSP (93 female, 113 male), followed up at a single centre between 1996 and 2001, were analysed retrospectively. They were regularly monitored for clinical and laboratory parameters for renal sequelae and relapse.

RESULTS

Nephritis was seen in 78 patients (38%), relapse in 52 (25%), and significant proteinuria in 39 (19%). In univariate analysis, an older age at onset (>10 years), persistent purpura, severe bowel angina, and relapse were identified as factors associated with nephritis and significant proteinuria. Relapse-related factors were an older age, persistent purpura, severe bowel angina, and leucocytosis. Logistic regression analysis showed that nephritis was significantly associated with an older age, persistent purpura, and relapse, and significant proteinuria was closely related to severe bowel angina and relapse.

CONCLUSION

We identified some predictors for nephritis, relapse, and significant proteinuria in childhood HSP, and close attention should be paid to those patients with the risk factors, such as an older age at onset, persistent purpura, severe bowel angina, and relapse.

[Urinary fibronectin excretion as a marker of disease activity in children with IgA nephropathy and Henoch-Schönlein nephropathy]

The increase of extracellular matrix proteins synthesis including fibronectin (FN) is associated with development of renal sclerosis. The aim of the study was to examine urinary FN excretion as a marker of renal changes in patients (pts) with IgAN and HSN. The study group consisted of 34 children: IgAN n=11 and HSN n=23, mean age 12.44 +/- 3.83 years. At the onset of illness we observed erytrocyturia in all children, proteinuria in 28: nephrotic sydrome in 14 pts (IgAN--4, HSN--10) and proteinuria in 14 children (IgAN--6, HSN--8). In mean time 0.6 years from the onset of illness renal biopsies were performed. Changes in light microscopy were graded I-V degrees according to the classification of WHO. FN was measured in 24-h urine collections (ng/mg of creatinine), using specific antibody (DAKO) and proteinuria (mg/24h). Mean time from the biopsies to examine FN was 0.76 +/- 1.16 years. FN excretion was analysed in 2 group pts: group A--with proteinuria (n=28); group B--with erytrocyturia (n=6). The control group (K) consisted of 14 healthy children. Renal function was normal in all.

RESULTS

The FN concentration higher than normal we observed in 22 pts (78.6%) in group A and 3 (50%) in group B. Mean FN value A was higher (NS) 274 +/- 213.0 than in B 132.0 +/- 68.8 and significant (p<0.01) than in group K (59.9 +/- 31.3). We found a positive correlation between FN and proteinuria in the moment of measurement the FN concentration (p=0.01, r=0.51). The higher values of FN (NS) we observed in pts with higher proteinuria at the onset of illness. FN excretion was significantly eleveted in younger children (p<0.001, r=-0,58). We not found a correlation between mean FN value and the grade of changes in renal biopsies (WHO).

CONCLUSION

Urinary FN excretion may be a marker of disease activity in children with IgAN and HSN.

The role of tumor necrosis factor-alpha in Henoch-Schonlein purpura

Henoch-Schonlein purpura (HSP) is one of the most common types of vasculitis disorders in childhood and is characterized by a rash, arthritis, abdominal pain, and renal involvement. The factors that determine and mediate the severity of HSP and its renal involvement remain poorly understood, although it is likely that pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha), are involved in the pathogenesis. Serum and urine levels of TNF-alpha were measured in children with HSP in the acute and convalescent phases by ELISA. Serum TNF-alpha levels were significantly higher in proteinuric HSP in the acute phase (36.6+/-8.5 pg/ml) compared with those with HSP without renal involvement and those with hematuric HSP (25.4+/-4.5 and 27.1+/-3.9 pg/ml) (P<0.005). However, these significantly higher levels disappeared in the convalescent phase. Using matched serum samples from the same patients, serum TNF-alpha levels of proteinuric HSP patients were significantly lower in the convalescent phase (29.9+/-4.6 pg/ml, P <0.05) than in the acute phase (39.1+/-8.2 pg/ml). Although urine TNF-alpha levels were higher in proteinuric HSP in the acute phase and reduced in the convalescent phase, there were no significantly high or low levels. These results suggest that increased TNF-alpha levels in the serum induce a series of functional and morphological changes in the glomerular cells in the acute phase and may be used as markers for monitoring the disease activity of HSP with severe renal involvement.

Urinary leukotriene E4 in Henoch-Schonlein purpura

BACKGROUND

Children with Henoch-Schonlein purpura (HSP) occasionally have allergic disease. We have previously shown that pranlukast hydrate was effective for purpura in HSP. Pranlukast hydrate is a leukotriene (LT) receptor antagonist; therefore, it is likely that LTs take part in the cause of HSP. Urinary leukotriene E4 (LTE4u) levels are a useful index of whole-body cysteinyl LT production in vivo. In this study, LTE4u was examined in children with HSP.

OBJECTIVE

The purpose of this study was to examine the relation between the level of LTE4u and the cause of HSP.

METHODS

Eighteen HSP children (six boys and 12 girls) and six healthy children were enrolled.

RESULTS

LTE4u levels in patients with HSP were significantly higher (P< 0.05) at the onset than those in healthy children. Four weeks therapy with pranlukast hydrate lowers LTE4u levels in patients with HSP (P< 0.05). There were no differences in LTE4u between the group of HSP patients with purpura nephritis and the group of HSP patients without purpura nephritis.

CONCLUSION

These results indicate that csyteinyl LTs may play a role in the pathophysiology of purpura in HSP.

Adrenomedullin and total nitrite levels in children with Henoch-Schönlein purpura

Nitric oxide (NO) is synthesized from endothelium and has an important role in the control of vascular tonus. Adrenomedullin (AM) is a potent vasodilator, and cytoprotective peptide is produced not only in adrenal medulla, but also in the vascular smooth muscle and endothelial cells. To investigate the endothelial synthesis of AM and NO, and endothelial injury in Henoch-Schönlein purpura (HSP), we measured their levels in 16 children with HSP, who were evaluated during the acute and remission phases, and compared with 12 healthy controls. Plasma AM levels (pmol/ml) were significantly higher in acute phase children (46.87+/-11.49) than in those in remission (35.59+/-12.39, p<0.01) and controls (30.70+/-9.12, p<0.001). Similarly, plasma total nitrite levels (mumol/l) were higher in acute phase patients (47.50+/-12.30) than in those in remission (35.94+/-10.08, p<0.005) and controls (34.56+/-11.51, p<0.05). Urinary excretion of AM (pmol/mg creatinine) was higher in acute phase patients (53.85+/-23.22) than in remission patients (29.97+/-9.33, p<0.01) and controls (37.43+/-15.78, p<0.05). Patients had increased urinary nitrite excretion (mumol/mg creatinine) in acute phase (2.39+/-1.18) compared to those in remission (1.53+/-0.90, p<0.05) and controls (1.05+/-0.61, p<0.005). There was no significant difference between remission phase and controls in AM and nitrite levels ( p>0.05). This study concluded that AM and NO may have a role in the immunoinflammatory process of HSP, especially in the active stage, although whether this perpetuates, or protects against, further vascular injury is not clear. Further studies are needed to clearly establish the roles of AM and NO in the pathogenesis of HSP.

Efficacy of methylprednisolone and urokinase pulse therapy for severe Henoch-Schönlein nephritis

OBJECTIVE

To evaluate the efficacy of methylprednisolone and urokinase pulse therapy (MUPT) for severe Henoch-Schönlein nephritis, we examined the clinical manifestation and prognosis of patients with MUPT on long-term observation.

METHODS

We enrolled 56 patients with Henoch-schönlein nephritis who had been diagnosed with at least type IIIb from 1980 to 1998 on long-term observation and had been treated with MUPT. The clinical features, laboratory data, and pathologic findings between "pre-MUPT" and "post-MUPT," and the prognosis of these patients on long-term observation were retrospectively investigated.

RESULTS

The mean urinary protein excretion after 6 months of treatment had decreased significantly compared with "pre-MUPT." Hypercoagulant state in "after the completion of urokinase pulse therapy" improved compared with "pre-MUPT." First renal biopsies were performed in all patients and second biopsies were performed in 27 patients. The activity index decreased significantly from 4.1 +/- 1.9 at first biopsy to 2.5 +/- 1.7 at second biopsy, while the chronicity index did not differ between first and second biopsy. None had renal insufficiency and renal survival rate was 100% for the decade.

CONCLUSIONS

Although uncontrolled, our study suggested that MUPT is effective for those patients with the risk of progression of their nephropathy, especially if started early during the course of the disease before the crescents become fibrous.

Risk factors of renal involvement and significant proteinuria in Henoch-Schönlein purpura

Risk factors of renal involvement and significant proteinuria in patients with Henoch-Schönlein purpura (HSP) were retrospectively evaluated by univariate and multivariate analyses. The analysis was performed in 134 patients with HSP. Renal involvement was found in 65 patients (49%) and 97% of the renal involvement was found within 3 months of disease onset. Moderate or severe proteinuria was recognised in 25 patients. A univariate analysis revealed that an age of more than 4 years at the onset, severe abdominal pain with gastrointestinal bleeding, persistent purpura over a month, coagulation factor XIII activity < 80%, and treatment with factor XIII concentrate were associated with developing renal involvement. A multivariate analysis showed that severe abdominal symptoms, an age of more than 4 years, and persistent purpura increased the risk of renal involvement. Risk factors of moderate or severe proteinuria were also examined. The risk factors in a univariate analysis were severe abdominal symptoms, persistent purpura, decreased factor XIII activity, treatment with steroids, and treatment with factor XIII concentrate. Of those, persistent purpura, treatment with factor XIII concentrate, and factor XIII activity < 80% were associated with significant proteinuria in a multivariate analysis. Among the patients with severe abdominal symptoms, factor XIII activity was significantly decreased in patients with significant proteinuria compared to other patients without significant proteinuria.

CONCLUSION

Long-term prognosis of Henoch-Schönlein purpura is dependent on the severity of renal involvement. In those patients who have the risk factors of renal involvement, especially significant proteinuria, close attention should be paid to a urinalysis for at least 3 months from the onset of the disease.

Morphological differences between glomerular epithelial cells (GEC) excreted during chemotherapy with antineoplastic drugs and GEC excreted in renal diseases

BACKGROUND

To better understand the mechanisms of glomerular epithelial cell (GEC) injuries in various diseases, we compared GEC excreted during chemotherapy (antineoplastic drugs) and GEC excreted in renal diseases.

METHODS

For 19 patients undergoing chemotherapy (85 courses), 69 patients with IgA nephropathy and 16 patients with Henoch-Schölein purpura nephritis, the number of excreted GEC and GEC casts were counted by an immunofluorescent study. The morphological features of GEC were also studied in an immunofluorescent study combined with Hoechst stain.

RESULTS

Glomerular epithelial cells were detected in 78% of the chemotherapy courses and in 94% of the patients with renal diseases. The GEC casts were observed in 2% of chemotherapy courses, while in renal diseases GEC casts were observed in 60% of the patients. Proteinuria (>30 mg/dL) and hematuria were not identified in any of the chemotherapy courses. The morphology and size of GEC were more variable than that in patients with nephropathy. Furthermore, GEC in patients undergoing chemotherapy often showed small nuclei and fragmented nuclei, which were rarely observed in patients with nephropathy.

CONCLUSIONS

These results showed that the detachment of podocytes was not directly associated with proteinuria or hematuria. The findings also suggest that GEC are damaged via an apoptotic process by chemotherapy. On the contrary, GEC may be detached through a non-apoptotic process in renal diseases.

Early tubular proteinuria and the development of nephritis in Henoch-Schönlein purpura

The prognosis of Henoch-Schonlein purpura (HSP) is mainly determined by the involvement of the kidney, but prognostic markers have not been established. To study the extent of tubular involvement in HSP and its relationship to the development of HSP nephritis, we measured the urinary excretion of two tubular marker proteins in 36 children with HSP. After admission, urinary N-acetyl-beta-D-glucosaminidase (NAG) was determined in 20 children and alpha1-microglobulin (alpha1-MG) in 16 children respectively. These values were compared with the biochemical data on admission, 1 month, 6 months, and 12 months later. A total of 198 24-h urine samples from healthy children were used for the establishment of reference data for NAG and alpha1-MG (mean+/-2 SD). Twenty-one patients had elevated excretion of either NAG (>mean+2 SD, n=12) or alpha1-MG (>mean+2 SD, n=9). The highest values (>mean+4 SD) were found in patients with early kidney involvement. Normal values were accompanied by a benign further clinical course. Children with intermediate high values (>mean+2 SD, <mean+4 SD) developed signs of renal involvement during follow-up. Hence, tubular proteinuria is common during the early stages of HSP. NAG and alpha1-MG levels correlate well with the extent of early and late renal involvement. Tubular marker proteins may be prognostic markers for the development of HSP nephritis.

Severe hypertension without urinary abnormalities in a patient with Henoch-Schönlein purpura

Hypertension as a complication of Henoch-Schönlein purpura (HSP) is almost uniformly accompanied by evidence of renal involvement, either decreased renal function or urinary abnormalities. We report a 4.5-year-old male with HSP who developed severe hypertension without other manifestations of glomerulonephritis, including no decline in renal function and no development of urinary abnormalities. Extensive evaluation for other identifiable causes for his hypertension was not productive. His hypertension resolved with the resolution of his HSP. This case demonstrates that patients with HSP may on occasion develop severe hypertension without other evidence of nephritis. An extensive evaluation for other causes of severe hypertension may be deferred in this setting until well after all other manifestations of HSP have resolved.

Increased excretion of tumor necrosis factor alpha and interleukin 1 beta in urine from patients with IgA nephropathy and Schönlein-Henoch purpura

Urinary proteins (5 mg/ml) collected from a group of 16 patients including 13 with IgA nephropathy and 3 with Schönlein-Henoch purpura (SHP) and from a control group consisting of 6 patients with diabetic nephropathy, 5 patients with hypertensive nephrosclerosis, and 5 healthy hospital staff members were studied for the contents of interleukins (IL) 1 beta, 2, 4, 6, and 12 and tumor necrosis factor alpha (TNF-alpha). Eleven patient with IgA nephropathy or SHP (11/16) but only 1 of the controls (1/16) had TNF-alpha activity in urinary proteins (p < 0.01). The IL-1 beta activity exhibited a similar tendency but to a lesser extent (10 of 16 patients with IgA nephropathy or SHP vs. 2 of 16 with other conditions, p < 0.05). Conversely, the detection rates of IL-2, IL-4, and IL-6 in both groups were not significantly different. IL-12 was not found in any of the samples from both groups. Sera and nonpurified urine samples from the same individuals were also measured for cytokines. IL-1 beta, IL-2, IL-4, and IL-12 were absent in all these samples, but TNF-alpha was found in four of the serum samples from patients with IgA nephropathy. Urinary proteins (2 mg/ml) were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, whereby peptides of 52, 49, 45, 34, 30, and 11 kD could be demonstrated in the patients with IgA nephropathy or SHP. Urinary proteins (200 micrograms/ml from patients with IgA nephropathy or SHP exerted a mitogen-like effect on the normal human mononuclear cells, as demonstrated by 3H-thymidine incorporation. In addition, these urinary proteins (400 micrograms/ml) enhanced the proliferative activity of the cultured rat glomerular mesangial cells. The exaggerated proliferation of rat glomerular mesangial cells exerted by urine proteins from 2 patients with active disease was markedly suppressed after treatment with glucocorticoids/cyclophosphamide. These results suggest that patients with IgA nephropathy or SHP can excrete excessive amounts of TNF-alpha and IL-1 beta in the urine. The inconsistent presence of these two cytokines in urine and serum may indicate that they can be produced locally and that they are implicated in the development of mesangial inflammation and glomerular damage.

The effect of triple therapy on rapidly progressive type of Henoch-Schönlein nephritis

Twelve patients with Henoch-Schönlein purpura, aged 6-14 years (mean 10.3 years), presenting with rapidly progressive glomerulonephritis (RPGN) were investigated prospectively. Analysis of the initial clinical features revealed: oedema (8 patients), hypertension (7 patients), gross haematuria (11 patients), oliguria (5 patients) and a decreased glomerular filtration rate (GFR) (< 40 ml/min per 1.73 m2, 8 patients). Renal biopsies were available in 9 patients and revealed focal necrotising and a fibroepithelial type of crescentic glomerulonephritis (with 60%-90% crescent formation). The remaining 3 patients fulfilled the clinical criteria of RPGN. Two patients who were in the acute stage required peritoneal dialysis for a period of 2 weeks. The treatment protocol in all patients consisted of intravenous pulse methylprednisolone (3 days), oral cyclophosphamide (2 months), oral dipyridamole (6 months) and oral prednisolone (3 months). At the end of triple therapy, GFR returned to normal in all but 1 patient. During a follow-up period of 9-39 months, 7 patients achieved complete remission, while 4 patients showed partial remission, 3 of whom had persistent proteinuria and haematuria and 1 microscopic haematuria only. One patient had persistent nephropathy with decreased GFR and macroscopic haematuria and nephrotic-range proteinuria. His renal biopsy, performed 30 months after the onset of the disease, showed chronic diffuse sclerosing glomerulonephritis and intratubular severe IgA deposition. Although our patient group was small, this type of intensive treatment appears to be effective; further studies are needed.

Immunomodulation with low-dose immunoglobulins for moderate IgA nephropathy and Henoch-Schönlein purpura. Preliminary results of a prospective uncontrolled trial

Recently, our group has shown that a 3-month course of intravenous immunoglobulin (2 g/kg/monthly) followed by 6 months of intramuscular immunoglobulins (IMIG, 16.5%, 0.35 ml/kg every 15 days) was able to slow or to stop the decline in the glomerular filtration rate, to reduce proteinuria, hematuria, leukocyturia and the histological index of activity on renal biopsy in patients with severe forms of IgA nephropathy (IGAN) and Henoch-Schönlein purpura (HSP). The aim of this open prospective trial was to evaluate the efficacy and safety of low-dose immunoglobulin therapy in moderate IGAN and HSP with permanent proteinuria. Fourteen patients with moderate IGAN [idiopathic IGAN: n = 11; chronic idiopathic HSP: n = 3] and permanent albuminuria were treated with polyvalent IMIG (16.5%) for 9 months (0.35 ml/kg once a week for 1 month, followed by 0.35 ml/kg every 15 days for a further 8 months). Eligibility criteria in the study were Lee histological stage I, II or III, albuminuria between 300 and 2,000 mg/day and a glomerular filtration rate > 70 ml/min/1.73 m2. IMIG were well tolerated and only 1 patient withdrew from the trial. No viral, renal or immunological side effects were observed. IMIG induced a significant decrease in albuminuria as well as in the histological activity index in the 11 cases in which a follow-up biopsy was performed. There was also a decrease in serum IgA, serum beta 2-microglobulin and IgA immune complex levels, and an increase in serum IgG1 levels. Twelve of the 13 evaluable patients improved during treatment.

[Studies on urinary protein components in renal disease in children, II--Comparison between children with orthostatic albuminuria and children with remission of glomerulonephritis]

The urinary protein components of 14 children with orthostatic albuminuria (group OA) and also that of 9 children with remission of IgA nephropathy or Henoch-Schönlein purpura nephritis (group GN) after forced lordosis were analyzed. The results were as follows; (1) Urinary total protein excretions after forced lordosis were greater than 30mg/dl in 50% of 26 children with remission of glomerulonephritis, therefore a high percentage of children with remission of glomerulonephritis were complicated with orthostatic albuminuria. (2) Urinary total protein excretions after forced lordosis were 150 +/- 91mg/dl in the group of OA and 149 +/- 88mg/dl in GN (p > 0.05). (3) In the urinary protein components, the percentage of urinary albumin and alpha 1-antichymotrypsin excretions were significantly higher in the OA group than the GN group (p < 0.01, p < 0.001 respectively), while the percentage of urinary transferrin, IgA and IgG excretions were significantly higher in the GN group than the OA group (p < 0.01, p < 0.001 and p < 0.05 respectively). (4) The ratio of urinary IgG/IgA and serum IgG/IgA was significantly lower in the GN group than the OA group (p < 0.05), suggesting that serum IgA tended to be excreted in urine in the GN group.

Impairment of lung diffusion capacity in Schönlein-Henoch purpura

Twenty-nine children with typical Schönlein-Henoch purpura (SHP) were tested at the initial phase of the disease for respiratory function. Of the 29 patients, 28 had a decrease of lung transfer for carbon monoxide (TLCO) as measured by a steady-state method. Lung volumes and blood gas values were normal; slight radiologic signs of interstitial lung involvement were observed in 18 of 26 patients. There was a decrease in TLCO to 56.8% of normal values for height and gender and to 58.5% when normal values were volume-adjusted to functional residual capacity. In 19 of 25 patients, TLCO measurements were performed at 3-month intervals during follow-up. In all cases, normalization of TLCO values was observed only after complete clinical recovery from SHP. All children with persisting symptoms, even limited to microscopic hematuria or slight proteinuria, had low TLCO values. In one patient low TLCO during follow-up preceded a late relapse of SHP in the form of acute nephritic disease with characteristic IgA deposits on renal biopsy. We conclude that low TLCO in SHP is probably related to alteration of the alveolar-capillary membrane by circulating immune complexes. This noninvasive technique may be useful in diagnosis, and during the follow-up of the disease as an early indicator of reactivation.

Long-term follow-up of childhood Henoch-Schönlein nephritis

A study of long-term outcome of 78 subjects who had had Henoch-Schönlein nephritis during childhood (at a mean of 23.4 years after onset) shows that severity of clinical presentation and initial findings on renal biopsy correlate well with outcome but have poor predictive value in individuals. 44% of patients who had nephritic, nephrotic, or nephritic/nephrotic syndromes at onset have hypertension or impaired renal function, whereas 82% of those who presented with haematuria (with or without proteinuria) are normal. 17 patients deteriorated clinically from an initial assessment in 1971; 7 of these had apparently completely recovered in 1976. 16 of 44 full-term pregnancies were complicated by proteinuria and/or hypertension, even in the absence of active renal disease. These findings indicate that childhood Henoch-Schönlein nephritis requires long-term follow-up, especially during pregnancy.

Fragments of urinary fibrin/fibrinogen degradation products and cross-linked fibrin degradation products in various renal diseases

In children with several kinds of glomerular disease, fragments of fibrin/fibrinogen degradation products (FDP) and cross-linked fibrin degradation products (XLFDP) in the urine were investigated by autoradiography using western blotting method. Results were compared with selectivity of proteins observed in cases of proteinuria, or with histological findings. Patients with nephrotic syndrome exhibited slightly increased amount of urinary FDP, consisted mainly of X and Y fragments. On the other hand, in cases of proliferative glomerulonephritis, such as acute glomerulonephritis, purpura nephritis, Ig A nephropathy, systemic lupus erythematosus, or hemolytic uremic syndrome, increased FDP, including XLFDP, was detected in the urine. In these cases, FDP was consisted mainly of fragments X, Y, and D-dimer, and could not be correlated with the degree of mesangial proliferation or with urinary protein selectivity. It was concluded that the increased urinary FDP and XLFDP were derived not only from filtration of plasma fibrinogen or FDP, but also from fibrinolysis of intraglomerular fibrin deposits.

Prognostic significance of urinary findings and renal biopsies in children with Henoch-Schönlein nephritis

Clinical course and renal biopsy were evaluated as predictors of renal outcome in 21 children with Henoch-Schönlein nephritis. Persisting heavy proteinuria and severe glomerular changes most accurately predicted those patients who were likely to develop renal failure. Renal biopsy is recommended only in patients with a nephrotic or nephritic/nephrotic picture.

Anaphylactoid purpura: hypertension with minimal urinary abnormalities

We wish to draw attention to a case of hypertension in a child with anaphylactoid purpura, but with minimal urinary findings. Early recognition and effective antihypertensive therapy for short periods of time prevent potential complications. The wide spectrum of presentations, the epidemiological features, the diagnostic work-up and the role of the primary care physician are also reviewed.