Pediatric case of crescentic post-streptococcal glomerulonephritis with myeloperoxidase anti-neutrophil cytoplasmic antibody.

Post-streptococcal glomerulonephritis (PSGN) generally has a good renal prognosis, and immunosuppressive therapies are not needed. However, a few patients present with severe acute kidney injury and extensive crescent formations. The etiology of such patients is not well known, and involvement of anti-neutrophil cytoplasmic antibodies is rarely reported. A 9-year-old girl with rapidly progressive nephritic syndrome was diagnosed with PSGN. A biopsy showed diffuse crescentic glomerulonephritis with immunoglobulin G and C3 deposits; moreover, humps were observed on electron microscopy. After she was administered methylprednisolone pulse therapy and intravenous cyclophosphamide, followed by prednisolone and azathioprine therapy, her urinary abnormalities improved and renal function normalized. However, the myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) titers gradually increased. We speculated that PSGN may be augmented by increased MPO-ANCA levels. Therefore, the patient is currently being treated with losartan, enalapril, azathioprine, and prednisolone. Although the MPO-ANCA titer remains high, urinary findings show mild proteinuria and her renal function has been norma for 18 months since onset. A progressive clinical course and severe histological findings may indicate the involvement of ANCA in deterioration of condition in patients with PSGN. Furthermore, in such cases immunosuppressive therapies should be considered even in pediatric PSGN.

Autoimmune neutropenia of infancy with recurrent urinary tract infections: a case report.

Autoimmune neutropenia of infancy is characterized by minor intercurrent infections despite severe neutropenia; severe bacterial infections are uncommon. An infant developed recurrent urinary tract infections at 9 and 11 months of age. The identified uropathogens were Escherichia coli and Enterococcus faecalis, respectively. Empirical treatment with carbapenems, as broad-spectrum antibiotics, promptly resolved the infection without sequelae. Febrile neutropenic children with cancer and autoimmune neutropenia can develop urinary tract infections; therefore, in such infants, urine culture should be obtained through catheterization. In febrile neutropenic infants with no apparent fever source, cephalosporin monotherapy should not be selected empirically because Enterococci can be the involved pathogens.

Role of ultrasound in revealing complications following percutaneous renal biopsy in children.

BACKGROUND: This retrospective case series aimed to investigate the role of ultrasound immediately post-percutaneous renal biopsy (PRB) for detecting post-biopsy complications in pediatric patients. METHODS: Data from 380 (male/female = 209/171) consecutive biopsies of native kidney tissue of 344 children from January 2001 to October 2009 were analyzed to investigate the role of an ultrasound immediately post-PRB and the predictive value of demographic, clinical, and baseline chemistry factors in predicting the risk of post-PRB complications. RESULTS: Post-PRB ultrasound identified hematoma formation in 33 (8.7%) patients. Of the 19 (5.0%) patients whose hematomas were large (≥ 1 cm), post-biopsy courses of 16 patients were clinically complicated. On the other hand, of the 14 patients whose hematomas were small (< 1 cm), all patients but one showed an uncomplicated clinical course. Of the 17 complications, 79.1% were detected within the first 24 hours and 21.9% (cases of resorption fever) between 24 and 144 hours post-PRB. Age ≥ 10 is an independent risk factor for post-PRB complication. CONCLUSIONS: Age ≥ 10 is an independent risk factor for post-PRB complication. After the procedure, the formation of a large hematoma predicted a complicated clinical course.

Methylprednisolone pulse therapy and intravenous cyclophosphamide therapy combined with cocktail therapy in severe pediatric Henoch-Schönlein purpura nephritis patient.

Henoch-Schönlein purpura (HSP) is a common self-limited vasculitis in children. The long-term prognosis depends on renal involvement. In severe Henoch-Schönlein purpura nephritis (HSPN) patients, >50 % have crescent formation and nephrotic syndrome that are important predicted outcomes. Therefore, for such patients, an aggressive immunosuppressive therapy is needed to prevent the progression. However, there is no consensus for an appropriate therapeutic regimen for severe pediatric HSPN patients. In this paper, we have reported on a 6-year-old boy who presented with HSPN with nephrotic syndrome and severe histopathological abnormalities; he was diagnosed with International Study of Kidney Disease in Children (ISKDC) grade IVb. Despite treatment with methylprednisolone pulse therapy, followed by oral prednisolone and dipyridamole; the nephrotic syndrome persisted. Subsequently, intravenous cyclophosphamide therapy (IVCY) (500-1,000 mg m-2 once a month for 7 months; total 6,000 mg m-2) was administered, followed by azathioprine and enarapril. Within 7 months of disease onset, complete remission was achieved. After 22 months of the initial renal biopsy, the second biopsy was performed to confirm treatment efficacy. Histopathological findings improved, and ISKDC grade IIIa was diagnosed. Even after 5 years of HSPN onset, complete remission and normal renal function is maintained. Although our evidence is restricted to single patient, we have shown that MPT and IVCY combined with cocktail therapy may be an effective treatment for severe pediatric HSPN.

Hereditary renal hypouricemia: a cause of calcium oxalate urolithiasis in a young female.

Although renal hypouricemia is mostly asymptomatic, it is known to present a high risk of exercise-induced acute renal failure, especially in young males. However, there is little information regarding the clinical features of urolithiasis as a complication in childhood renal hypouricemia. Here we report a 4-year old female with idiopathic renal hypouricemia who presented with macroscopic hematuria due to obstructive calcium oxalate urolithiasis. She was treated successfully with percutaneous nephrolithotripsy and thereafter hematuria disappeared. Sequence analysis of the patient and her family's URAT1 gene confirmed a nonsense mutation in exon 4 (W258X). To the best of our knowledge, this is the youngest case of hereditary renal hypouricemia caused by URAT1 gene mutation, which was found by hematuria due to calcium oxalate urolithiasis.

Early treatment with methylprednisolone pulse therapy combined with tonsillectomy for heavy proteinuric henoch-schönlein purpura nephritis in children.

BACKGROUND: There is no clear consensus as to which patients with Henoch-Schönlein purpura nephritis (HSPN) at risk of a poor outcome should be treated and what therapeutic regimen should be used. METHODS: Nine children with heavy proteinuric HSPN received prompt initiation of methylprednisolone pulse therapy (MPT) combined with tonsillectomy in a prospective study. RESULTS: At presentation, the mean values for the patients' urine protein excretion (early-morning urinary protein/creatinine ratio), serum IgA, activity index (AI), and chronicity index (CI) were 5.0 ± 5.6 g/g Cr, 135.6 ± 56.5 mg/dl, 4.0 ± 0.7, and 1.7 ± 1.3, respectively. At the second biopsy, conducted approximately 24 months after initiation of therapy, the patients' serum albumin had significantly increased (4.4 ± 0.2, p < 0.01), and the serum IgA and AI had significantly decreased (88.1 ± 30.8 mg/dl, p < 0.05; 2.0 ± 1.2, p < 0.01, respectively), whereas the CI remained unchanged. Proteinuria disappeared within 24 months in all but 1 patient, and hematuria disappeared within 38 months in all patients. No patient showed renal impairment or experienced a recurrence and/or exacerbation of HSP/HSPN. CONCLUSIONS: Early treatment with MPT combined with tonsillectomy is effective in ameliorating the histopathological progression and improving the clinical course of children with heavy proteinuric HSPN.

A case report of dysosteosclerosis observed from the prenatal period.

Dysosteosclerosis is a sclerosing bone dysplasia with skeletal changes resembling those of osteopetrosis. The disorder is associated with dental anomalies and occasionally mental retardation. Because of the rarity and phenotypic diversity of dysosteosclerosis, it remains unsolved whether or not the disorder is heterogeneous. We report here on an affected boy associated with brain calcification and epilepsy with developmental delay. Prenatal ultrasound revealed ventriculomegaly, and brain CT in the neonatal period showed periventricular calcifications. At 13 mo of age, he presented with generalized convulsion with developmental delay. Metaphyseal sclerosis, metaphyseal undermodeling, and oval-shaped vertebral bodies on skeletal survey warranted a diagnosis of dysosteosclerosis. Retrospective review of radiographs as a neonate showed metaphyseal radiolucency, but not metaphyseal sclerosis. Since then, neither the bone changes nor neurological symptom has progressively worsened up to 4 yr of age. Thus, it is thought that the clinical and radiological manifestations of the sclerotic disorder become obvious during infancy. Brain calcification of prenatal onset may be an essential syndromic constituent of the disorder.