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

Efficacy and Safety of Tacrolimus in the Treatment of Pediatric Henoch-Schönlein Purpura Nephritis

BACKGROUND

Children with severe Henoch-Schönlein purpura nephritis (HSPN) may progress to end-stage renal disease without appropriate treatment.

OBJECTIVE

This study aimed to investigate the efficacy and safety of tacrolimus combined with glucocorticoids in the treatment of pediatric HSPN.

METHODS

A total of 87 HSPN patients with urinary protein ≥ 0.75 g/24 h received standard of care, including angiotensin II receptor blockers/angiotensin-converting enzyme inhibitors and glucocorticoids. Patients were divided into three groups and additionally received tacrolimus (n = 30), cyclophosphamide (n = 31), or mycophenolate mofetil (MMF) (n = 26). We monitored outcome measures, including proteinuria, hematuria, and renal function and analyzed the efficacy and side effects in each group.

RESULTS

At 2-month follow-up, the overall efficacy was 93.3%, 83.9%, and 61.5% for tacrolimus, cyclophosphamide, and MMF, respectively (P < 0.05). Urinary protein significantly decreased for all groups. Urinary red blood cell counts significantly decreased for patients treated with tacrolimus (P < 0.001) and cyclophosphamide (P < 0.05), whereas no significant decrease was seen for those receiving MMF (P = 0.09). Although urine β2-microglobulin significantly decreased following 2 months of treatment with all medications, efficacy was greater with tacrolimus than with cyclophosphamide and MMF (P < 0.001). Major adverse events were respiratory and urinary infections, with MMF having the highest infection rate. The cyclophosphamide group also experienced additional adverse events, including arrhythmia, hemorrhagic cystitis, leukocytosis, thrombocytopenia, and hyperglycemia.

CONCLUSIONS

These results indicate that tacrolimus is more effective at reducing proteinuria and hematuria and improving renal function, with relatively milder side effects, in the treatment of pediatric HSPN.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2200055323, retrospectively registered on January 7, 2022.

The Diagnostic Role of Urinary N-Acetyl-β-D-glucosaminidase (NAG) Activity in the Detection of Renal Tubular Impairment

The kidney function can be assessed by a number of methods. The urinary excretion of enzymes, in particular N-acetyl-β-D-glucosaminidase (NAG), is considered a relatively simple, cheap, fast and non-invasive method in the detection and follow-up of renal tubular function under various conditions. The determination of urinary NAG provides a very sensitive and reliable indicator of renal damage, such as injury or dysfunction due to diabetes mellitus, nephrotic syndrome, inflammation, vesicoureteral reflux, urinary tract infection, hypercalciuria, urolithiasis, nephrocalcinosis, perinatal asphyxia, hypoxia, hypertension, heavy metals poisoning, treatment with aminoglycosides, valproate, or other nephrotoxic drugs. This paper gives an overview of the current use of urinary NAG in the detection of renal injury.

The Spectrum of Kidney Diseases in Children Associated with Low Molecular Weight Proteinuria

BACKGROUND

Proteinuria, in addition to haematuria, is the most important laboratory parameter in patients with nephro-urological diseases. Low molecular weight proteinuria (LMWP) is of particular importance because some diseases genetic and tubulointerstitial are diagnosed based on its presence.

AIM

The purpose of this study is to describe the clinical features, the course and outcome of pediatric patients with a renal disease associated with LMWP.

MATERIAL AND METHODS

This retrospective observational study included 250 pediatric patients with various kidney diseases in which the type of proteinuria was defined by 4-20% gradient gel sodium dodecyl sulphate polyacrylamide gel (SDS-PAG) electrophoresis.

RESULTS

Isolated LMWP was detected in 12% of patients, while mixed glomerulotubular proteinuria was detected in 18% of patients. It was detected in all patients with the Dent-1/2 disease, Lowe's syndrome and secondary Fanconi syndrome. Transient LMWP was also detected in a series of 12 patients with distal renal tubular acidosis. In patients with nephrotic syndrome, it was associated with corticoresistence and unfavourable clinical course.

CONCLUSION

This study contributes to the understanding of the clinical spectrum of various kidney diseases associated with LMWP, their natural course, and the effect of therapy.

Evaluation of TGF-β1 and MCP-1 expression and tubulointerstitial fibrosis in children with Henoch-Schönlein purpura nephritis and IgA nephropathy: A clinical correlation

OBJECTIVES:

Henoch-Schönlein purpura nephritis and immunoglobulin A nephropathy are two diseases with similar clinical presentations but very different prognoses. Transforming growth factor β1 and monocyte chemoattractant protein-1 have been associated with the development of tissue fibrosis. We examined the development of tubulointerstitial fibrosis and its relationship with Transforming growth factor β1 and monocyte chemoattractant protein-1 expression in these patients.

METHODS:

Renal tissue samples were collected by renal biopsy from 50 children with Henoch-Schönlein purpura nephritis and 50 children with immunoglobulin A nephropathy. Hematoxylin and eosin and Masson's trichrome-stained tissues were examined using light microscopy. Tubulointerstitial fibrosis was graded using the method described by Bohle et al. (1). The immunohistochemical detection of Transforming growth factor β1 and monocyte chemoattractant protein-1 expression was correlated with the tubulointerstitial fibrosis grade. Clinical Trial registration number: ZJCH-2012-0105.

RESULTS:

Transforming growth factor β1 and monocyte chemoattractant protein-1 expression in the renal tissues was significantly greater in the patients with immunoglobulin A nephropathy than in the patients with Henoch-Schönlein purpura nephritis (both p<0.001). The immunoglobulin A nephropathy patients had a higher tubulointerstitial fibrosis grade than the Henoch-Schönlein purpura nephritis patients (p<0.001). The tubulointerstitial fibrosis grade was in accordance with the Transforming growth factor β1 and monocyte chemoattractant protein-1 expression levels in both diseases (both p<0.001).

CONCLUSION:

Transforming growth factor β1 and monocyte chemoattractant protein-1 expression was associated with the development of immunoglobulin A nephropathy and Henoch-Schönlein purpura nephritis. Further studies are needed to better evaluate this association.

Vasculitis in children

Vasculitis is rare in children, and, apart from HSP and perhaps KD, most practicing pediatricians will never encounter a case. Nonetheless, progress in the diagnosis and treatment of these conditions has afforded most children with vasculitis a reasonably good prognosis. Accordingly, it is important to consider vasculitis as a potential cause of unexplained inflammation, perplexing rashes, or strange combinations of symptoms. Although evaluation and management of suspected vasculitis are difficult in the best of situations, they are impossible if the diagnosis is not considered.

[Nephropathy in Schönlein-Henoch purpura: a retrospective study of the last 25 years]

Schönlein-Henoch purpura is a systemic vasculitis due to IgA-mediated hypersensitivity, almost exclusively affecting the pediatric age group. Long-term prognosis is mainly conditioned by renal involvement, which can appear at onset or during the course of the disease. To evaluate renal involvement, 764 patients with Schönlein-Henoch purpura were retrospectively reviewed. Of these, 153 (20 %) had renal involvement, the most frequent form of presentation being non-nephrotic hematuria/proteinuria (67 patients) followed by isolated hematuria (41 patients). Renal biopsy was performed in 39 patients, and the most frequent pathological findings were diffuse mesangial proliferation with IgA deposits and less than 50 % of crescentic glomeruli. Treatment was not curative. Three patients (2 %) progressed to end-stage renal failure and required renal transplantation. One patient died. Notably, two of the patients who underwent renal transplantation had disease recurrence. We stress that nephropathy is usually benign and that it requires long-term follow-up.

Development of acute Henoch-Schönlein purpura subsequent to endodontic treatment

BACKGROUND

Henoch-Schönlein purpura (HSP) is an inflammatory disorder of unknown origin that is characterized by IgA-dominant immune complexes in smaller blood vessels. It results in a triad of symptoms, including a purpuric rash on the lower extremities, abdominal pain or renal involvement, and arthritis. Any of the triad may be absent, however, which often leads to confusion in diagnosing the condition. Cases of acute HSP developing subsequent to dental treatment have not been previously reported in the dental literature.

CASE REPORT

This study reports the unusual case of a 14-year-old female who developed acute HSP following endodontic treatment.

CONCLUSION

Treatment for this condition is supportive and children affected by this disorder need close follow-up of their renal status.

Life-threatening purpura and vasculitis

Palpable purpura, the inflammation of blood vessels is the hallmark of vasculitis. It can be observed in a variety of settings, where vessels can be affected primarily or as a secondary event. Every patient with vasculitis should be considered to have a systemic disease unless proven otherwise. One or more systemic symptoms occur in at least 50% of patients and there is no way to predict systemic involvement. Patients may demonstrate mild systemic involvement like arthralgia and arthritis, fever and malaise or more severe symptoms such as massive proteinuria and raised creatinine leading to chronic renal failure, severe intestinal bleeding or perforation with a fatal outcome. In this article we will review the life-threatening aspects of purpura and vasculitis.

Vasculitis in children

This article provides a general overview of vasculitis, situations in which the diagnosis should be considered, diagnostic methods, and therapeutic considerations. Details and treatments unique to specific vasculitides are also reviewed.

Pediatric IgA nephropathies: clinical aspects and therapeutic approaches

The pediatric IgA nephropathies are IgA nephrothapy (Berger's Disease) and Henoch-Schönlein purpura nephritis. Both conditions are reviewed in detail with respect to epidemiology, clinical features, outcome, prognostic markers, and therapeutic approaches. For both conditions variable disease severity and outcome along with the lack of conclusive evidence for efficacy of treatment based on randomized clinical trials makes it difficult to make strong recommendations regarding therapy.

Vasculitis in childhood

Vasculitis is an important diagnostic consideration in the child with prolonged fever, unexplained pains, new neurologic findings, or other persistent and troubling signs of inflammation. As long as the etiology of vasculitis remains unknown, reliance upon imperfect diagnostic criteria is likely to remain the state of the art. Nonetheless, anti-inflammatory and immunosuppressive therapy is highly effective in speeding resolution of systemic inflammation and reducing long-term complications. The care, experience, and acumen of the treating physician thus remain the gold standard for diagnosing and treating pediatric vasculitides. In all cases this begins with a high level of suspicion in the primary care physician.

Vasculitis in childhood

Inadequate understanding of the pathogenesis and etiology of vascular inflammation continues to hinder progress in the diagnosis and treatment of pediatric vasculitis. The greatest amount of work is being done in the most common vasculitides of childhood, including Kawasaki disease and Henoch-Schönlein purpura. Discussion of rarer types of vasculitis, on the other hand, such as antineutrophil cytoplasmic antibody-positive small vessel diseases, is largely restricted to case reports. Most aspects of the care of children with Wegener granulomatosis and microscopic polyangiitis are derived by extrapolating from data about adults. Virtually no data are available concerning ways in which these diseases may be different in children.