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

Risk Factors Associated with Renal Involvement in Childhood Henoch-Schönlein Purpura: A Meta-Analysis

BACKGROUND AND OBJECTIVE

Henoch-Schönlein purpura (HSP) is an important cause of chronic kidney disease in children. This meta-analysis identified risk factors associated with renal involvement in childhood HSP.

METHODS

PubMed, Embase, and Web of Science were searched. The quality of all eligible studies was assessed using the Newcastle-Ottawa scale criteria. An analysis of possible risk factors was conducted to report the odds ratio (OR) and weighted mean difference (WMD).

RESULTS

Thirteen studies (2398 children) revealed 20 possible and 13 significant risk factors associated with renal involvement in HSP, with the following meta-analysis estimates of OR and WMD, with 95% confidence intervals: older age (0.90, 0.61-1.19); age > 10 y (3.13, 1.39-7.07); male gender (1.36, 1.07-1.74); abdominal pain (1.94,1.24-3.04); gastrointestinal bleeding (1.86, 1.30-2.65); severe bowel angina (3.38, 1.17-9.80); persistent purpura (4.02, 1.22-13.25); relapse (4.70, 2.42-9.14); WBC > 15 × 109/L (2.42, 1.39-4.22); platelets > 500 × 109/L (2.98, 1.22-7.25); elevated antistreptolysin O (ASO) (2.17, 1.29-3.64); and decreased complement component 3 (C3) (3.13, 1.62-6.05). Factors not significantly associated with renal involvement were: blood pressure; orchitis; elevated C-reactive protein; elevated erythrocyte sedimentation rate (ESR); and elevated serum IgA/IgE or IgG. Arthritis/arthralgia may be a risk factor according to the criteria of the American College of Rheumatology (1.41, 1.01-1.96).

CONCLUSION

The following are associated with renal involvement in pediatric HSP: male gender; > 10 y old; severe gastrointestinal symptoms (abdominal pain, gastrointestinal bleeding, and severe bowel angina); arthritis/arthralgia; persistent purpura or relapse; WBC > 15 × 109/L; platelets > 500 × 109/L; elevated ASO; and low C3. Relevant clinical interventions for these risk factors may exert positive effects on the prevention of kidney disease during the early stages of HSP. However, the results should be interpreted cautiously due to the limitations of the studies.

Adjuvant treatments for Henoch-Schönlein purpura nephritis in children: A systematic review

BACKGROUND

The management of Henoch-Schönlein purpura nephritis (HSPN) in childhood is controversial. Adjuvant therapies such as immunoglobulin, anticoagulants, and vitamins have been used with conventional treatments despite a lack of evidence of their efficacy.

OBJECTIVE

The aim of this study was to review the scientific literature regarding adjuvant treatments administered with conventional drugs in the treatment of childhood HSPN.

METHODS

Published articles were identified from the MEDLINE and EMBASE databases (1988-December 2008; key words: Henoch-Schönlein nephritis and Henoch-Schönlein purpura). The search was limited to published English-language studies on therapeutic options for HSPN in children.

RESULTS

A total of 12 studies were identified and included in this review; most (n = 8) were case series or retrospective studies. Studies of conventional therapy combined with adjuvant treatment should be interpreted with caution. In particular, factor XIII administration was reported to improve kidney symptoms in 1 study. Based on the results from 9 studies, no convincing evidence on intravenous immunoglobu-lin, urokinase, or anticoagulants was identified. No substantial information was available on the benefit of antiplatelet agents or heparin in treating HSPN. Integrating treatment with vitamin E was not recommended based on the results from 1 randomized controlled trial. Fish oil was reported to be effective in 1 case series.

CONCLUSIONS

Studies concerning the treatment of HSPN in children with adjuvant therapies were retrospective and recommendations were drawn from level IV evidence. One randomized controlled trial on the use of tocopherol as adjuvant treatment was identified; however, no clinical utility was reported. At present, there is no strong evidence supporting benefits with the use of adjuvant treatments.

Treatment-based literature of Henoch-Schönlein purpura nephritis in childhood

Considerable concern has been expressed on the importance of identifying an improved therapeutic protocol for use in the treatment of childhood Henoch-Schönlein purpura nephritis, primarily due to the unpredictable success shown to date in improving long-term renal outcome. This review focuses on published reports describing the outcomes of therapeutic approaches currently being used in the treatment of pediatric Henoch-Schönlein purpura nephritis, with the aim of providing information that will facilitate a treatment-based approach in children presenting with varying degrees of kidney disease. The conclusions of the authors of this review are that currently prescribed treatments of children affected by Henoch-Schönlein purpura nephritis are not adequately guided by evidence obtained in properly designed, randomized, placebo-controlled trials with outcome markers related to the progression to end stage renal disease (level I evidence). Moreover, firm evidence supporting the best practice to be applied with the aim of delaying the progression of kidney disease is still lacking.

Treating severe Henoch-Schönlein and IgA nephritis with plasmapheresis alone

The aim of our study was to determine the outcome of children with severe Henoch-Schönlein nephritis (HSN) and immunoglobulin A (IgA) nephritis (IgAN) treated with early plasmapheresis alone. Children with acute renal impairment, heavy proteinuria or both and histology greater than grade 3 were treated with early plasmapheresis alone. Glomerular filtration rate (GFR) estimated from plasma creatinine (eGFR), urine albumin:creatinine ratio (UA/UC) and blood pressure 2 weeks after treatment and were measured at the last follow-up. Sixteen children (14 HSN, 2 IgAN) had a mean eGFR of 56 (17-136) ml/min per 1.73 m2 and UA/UC of 590 (12-1,379) mg/mmol. Fifteen were referred at presentation and one after 2 months, and all commenced plasmapheresis within 6 (2-13) days. All had at least nine exchanges of 90 ml/kg over 2 weeks. At 2 weeks, the eGFR had increased by 51 (95% CI 34-68; P=0.002), and the UA/UC fell by 457 (95% CI 241-673; P=0.0001). At last review after 4 (1-7.5) years, the late-referred child had required a renal transplant but the other 15 had normal eGFRs (98-142), did not require hypotensive medication, and had normal or minimally elevated UA/UC (maximum 42). Children with severe HSN and IgAN recover well if treated with plasmapheresis alone without the need for immunosuppressive therapy. A randomised trial is needed.

Long-term outcome in children after Henoch-Schonlein purpura nephritis

This study investigated predictors of renal survival in children with Henoch-Schönlein purpura glomerulonephritis. Records of patients with Henoch-Schönlein purpura glomerulonephritis evaluated at our center, from 1953-1990, were reviewed. Data were abstracted from records of patients seen within 5 years. Others were mailed a questionnaire or contacted by telephone. Primary outcome measures were renal survival and presence of urinary abnormalities or hypertension. Of the 65 eligible patients with Henoch Schönlein purpura glomerulonephritis, follow-up data was obtainable for 81.5%. The median follow-up was 20 years. At last follow-up, 66% of patients had normal renal function and urinalyses, and 21% had progressed to end-stage renal disease. The only factor associated with the development of end-stage renal disease was the use of cytotoxic agents. There are no features at initial presentation that identify children at risk of disease progression. Close follow-up of all children with Henoch Schönlein purpura glomerulonephritis is warranted.

Prediction of total body water in infants and children

BACKGROUND

In paediatric clinical practice treatment is often adjusted in relation to body size, for example the calculation of pharmacological and dialysis dosages. In addition to use of body weight, for some purposes total body water (TBW) and surface area are estimated from anthropometry using equations developed several decades previously. Whether such equations remain valid in contemporary populations is not known.

METHODS

Total body water was measured using deuterium dilution in 672 subjects (265 infants aged <1 year; 407 children and adolescents aged 1-19 years) during the period 1990-2003. TBW was predicted (a) using published equations, and (b) directly from data on age, sex, weight, and height.

RESULTS

Previously published equations, based on data obtained before 1970, significantly overestimated TBW, with average biases ranging from 4% to 11%. For all equations, the overestimation of TBW was greatest in infancy. New equations were generated. The best equation, incorporating log weight, log height, age, and sex, had a standard error of the estimate of 7.8%.

CONCLUSIONS

Secular trends in the nutritional status of infants and children are altering the relation between age or weight and TBW. Equations developed in previous decades significantly overestimate TBW in all age groups, especially infancy; however, the relation between TBW and weight may continue to change. This scenario is predicted to apply more generally to many aspects of paediatric clinical practice in which dosages are calculated on the basis of anthropometric data collected in previous decades.

Risk of long term renal impairment and duration of follow up recommended for Henoch-Schonlein purpura with normal or minimal urinary findings: a systematic review

BACKGROUND

The duration of follow up to assess the risk of long term renal impairment in Henoch-Schönlein purpura (HSP) without nephritic or nephrotic syndrome or renal failure on diagnosis remains undetermined.

AIMS

To undertake a systematic review of the literature to assess whether the risk of long term renal impairment without renal involvement on diagnosis could be estimated and to determine the time period when renal involvement is very unlikely after the diagnosis of HSP.

METHODS

Search of studies of unselected children with HSP, and available information on urinary findings, renal involvement, and long term renal function follow up. Studies of selected children with HSP nephropathy at diagnosis were excluded.

RESULTS

Twelve studies of 1133 children were reviewed. The follow up period ranged from 6 weeks to 36 years. Proteinuria and/or haematuria, which occurred in 34.2%, of which only one fifth were in association with nephritic or nephrotic syndrome, developed in 85% of cases within 4 weeks of the diagnosis of HSP, in 91% within 6 weeks, and in 97% within 6 months. Permanent renal impairment never developed after normal urinalysis; it occurred in 1.6% of those with isolated urinary abnormalities, and in 19.5% of those who developed nephritic or nephrotic syndrome.

CONCLUSION

No long term renal impairment occurred after normal urinalysis. Even if urinalysis is normal at presentation, the testing should be continued for six months. There is no need to follow up after the first six months those whose urinalysis remains normal.

Henoch-Schönlein purpura

Henoch-Schönlein purpura (HSP) is a multisystem immunoglobulin A-mediated vasculitis with a self-limited course affecting the skin, joints, gastrointestinal tract, and kidneys. HSP occurs most often in children between the ages of 3 and 10 years, and presents classically with a unique distribution of the rash to the lower extremities and the buttocks area. For this reason, a skin biopsy in children is rarely necessary for diagnosis. However, in the very young age children and adults, the rash is not classically distributed, and therefore a skin biopsy is often needed. Although there are currently no prospective controlled studies on the treatment of the different manifestations of HSP, there are several retrospectively designed studies and other physicians' personal experiences supporting the use of steroids in patients with severe gastrointestinal, severe renal, central nervous system, and testicular involvements. Severe renal and central nervous system disease may lead to life-threatening conditions, and immunosuppressive agents and plasmapheresis may be needed. The overall prognosis in HSP is excellent, but the long-term morbidity depends on the renal and neurologic involvement. One third to one half of these patients will have one or more recurrences of symptoms, usually within 6 weeks, but may occur as late as 3 to 7 years later.

Regression of Henoch-Schönlein disease with intensive immunosuppressive treatment

OBJECTIVE

To assess the results of a new immunosuppressive cycle, which had given favorable results in other immune-mediated glomerulonephritides, in the treatment of Henoch-Schönlein disease.

METHODS

Eight patients (seven male and one female; age range, 13 to 61 years) with biopsy-proved Henoch-Schönlein were treated with the following protocol: (1) induction with 250 to 750 mg intravenous methylprednisolone every day for 3 to 7 days plus 100 to 200 mg oral cyclophosphamide every day, (2) maintenance with 100 to 200 mg oral prednisone on alternate days plus cyclophosphamide, as before, for 30 to 75 days; (3) tapering, with prednisone reduced on average by 25 mg every month while the cyclophosphamide dose remained the same, and (4) discontinuation, after at least 6 months, with abrupt interruption of cyclophosphamide and slow tapering of prednisone. The results were assessed in terms of remission, improvement, progression of disease, kidney failure, and death, unambiguously defined. The follow-up extended up to 12 years.

RESULTS

Seven of eight patients had a complete remission that was maintained indefinitely thereafter. Plasma creatinine levels decreased on average from 211 +/- 81 to 92 +/- 27 mumol/L (p < 0.01) and urine protein excretion decreased from 1.9 +/- 0.8 to 0.3 +/- 0.1 gm/day (p < 0.01). One patient died of intestinal infarction caused by atherosclerotic mesenteric artery thrombosis.

CONCLUSIONS

Our data suggest that an intensive immunosuppressive regimen that combines prednisone and cyclophosphamide at high doses can be effective in healing Henoch-Schönlein disease.

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.

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.

Anaphylactoid purpura: characteristics of 16 patients who progressed to renal failure

Renal insufficiency occurs in at least 1.5% of children with anaphylactoid purpura (AP). We reviewed the records of 16 children who developed end-stage renal disease (ESRD group) secondary to AP and matched them for age, era of onset, renal histology, and clinical severity at onset with 16 children who had AP but whose creatine clearance returned to and remained normal (recovery group). We reviewed creatinine clearances at 1, 3, 5, and 10 years after onset. A creatinine clearance greater than 70 ml/min per 1.73 m2 was present in 50% of the patients in the ESRD group at 3 years and in 25% at 5 years after onset. In contrast, all patients in the recovery group had a creatinine clearance greater than 70 ml/min per 1.73 m2 by 3 years (7 of 16 had a creatinine clearance greater than 125 ml/min per 1.73 m2) and all were normal 95-125 ml/min per 1.73 m2) by 5 years. Thus, the presence of an increased creatinine clearance (greater than 125 ml/min per 1.73 m2) at 3 years predicted recovery, while failure to reach a creatinine clearance of greater than 70 ml/min per 1.73 m2 at 3 years predicted progression to ESRD. There was no evidence of recurrent systemic AP or nephritis in the 14 patients who underwent renal allograft transplantation. We conclude that long-term evaluation of patients over many years is required to identify those who will progress to ESRD from AP and that recurrence of AP in the renal transplant is uncommon.