Pirarubicin Combination Low-Dose Chemotherapy for Early Infantile Stage MS Neuroblastoma: Case Report.

Neuroblastoma (NB) is a neural crest-derived malignant tumor which is diagnosed during infancy in approximately 40% of cases; spontaneous regressions are observed, but there are varying degrees of severity. Treatment is indicated if an infant's condition is at risk of deterioration. Herein, we report the case of a 42-day-old boy who presented with hepatomegaly and was diagnosed with stage MS NB. A pathological diagnosis of "poorly differentiated neuroblastoma with low mitosis-karyorrhexis index, favorable histology" was made; his tumor cells were hyperdiploid and MYCN was not amplified. Because he had respiratory distress caused by the rapidly evolving hepatomegaly, two cycles of chemotherapy containing vincristine and cyclophosphamide were administered in the second and fourth weeks of admission; however, his abdominal tumor did not shrink. In the sixth week of admission, chemotherapy was revised to pirarubicin and cyclophosphamide, and the tumor began to shrink. After discharge, there was no re-elevation of tumor markers; after 1 year, the hepatomegaly and liver metastases disappeared. During the 5-year follow-up, his growth and development were normal and he progressed without sequelae. A regimen that includes pirarubicin could merit further study in the treatment of early infants with stage MS low-risk NB who are at risk of complications.

Nonfunction of the ECT2 gene may cause renal tubulointerstitial injury leading to focal segmental glomerulosclerosis.

BACKGROUND: Secondary focal segmental glomerulosclerosis (FSGS) follows congenital or acquired tubulointerstitial alterations such as in Dent's disease, Lowe syndrome, and reflux nephropathy. Failure of adequate regeneration after tubulointerstitial injury, or abnormal tubulogenesis, can disturb intrarenal blood circulation, causing excessive glomerular filtration. The epithelial cell-transforming sequence 2 gene (ECT2) contributes to tight junction function in epithelial cells. METHODS: We encountered two patients with a nonfunctioning ECT2 genotype who later developed FSGS. Both developed proteinuria associated with acute renal failure in early childhood. RESULTS: Renal biopsy specimens showed marked tubulointerstitial nephritis at the onset of proteinuria, later progressing to FSGS consequent to tubulointerstitial injury. The patients did not respond to corticosteroids and attained only incomplete remission upon cyclosporine A administration. One patient received a maternal renal transplant with good function and no rejection. CONCLUSIONS: ECT2 is important for tight junction function and maintenance of cell polarity. Nonfunction of this gene may cause renal tubulointerstitial injury, progressing to glomerular sclerosis.

Renal tubular dysgenesis and tubulointerstitial nephritis antigen in juvenile nephronophthisis.

AIM: The relationship between abnormalities of tubular architecture and tubulointerstitial nephritis antigen (TIN-ag) in juvenile nephronophthisis (J-NPH) was evaluated. METHODS: Sixteen J-NPH patients were examined. Nephrocystin-1, TIN-ag, type IV collagen, Fas antigen and the C5b-9 complement complex were stained by immunohistochemical methods. RESULTS: Renal tubules of patients with J-NPH showed morphological abnormalities of tubular basement membranes (TBM) and frequent apoptosis of tubular epithelial cells. Additionally, the C5b-9 complement complex was deposited within the TBM in the absence of immunoglobulin deposition, suggesting complement-dependent TBM injury. Localization of TIN-ag in the TBM of J-NPH patients disclosed a partial defect or discontinuity in 14 of the 16 patients, while type IV collagen immunoreactivity was relatively preserved. These findings suggest that tubulogenesis is disturbed during nephronogenesis in J-NPH patients because of a defect in nephrocystin, an NPHP gene product. TBM defects induce further morphological abnormalities such as cystic dilation of tubules; as tubular function impairment advances, the incomplete tubules may be injured by C5b-9 complement complexes, followed by apoptotic cell death. CONCLUSION: TIN-ag, which is important in early nephrogenesis, lacks normal activity, and vulnerable and incomplete tubules with deficient TIN-ag expression are formed. Removal of these defective tubules by apoptosis combined with the C5b-9 complement complex could be the primary reason for progression to end-stage renal disease in J-NPH patients.

Cyclosporine A causes maturation failure in embryonic-type glomeruli persisting after birth.

INTRODUCTION: We analyzed renal histologic and immunohistologic findings in children with nephrotic syndrome (NS) who did (n=5) or did not (n=17) develop cyclosporine A (CyA) nephropathy despite appropriately low serum CyA concentrations being maintained over 2 years. METHODS: To discriminate embryonic-type from mature glomeruli, we performed staining for type IV collagen a1, laminin ß1 and laminin ß2. Staining patterns were used to semiquantitatively assess glomerular immaturity (glomerular immaturity index, or GII). RESULTS: In follow-up biopsy specimens, residual embryonic-type, collapsed embryonic-type and sclerotic glomeruli that had failed to differentiate were observed. Patients with early-onset CyA nephropathy had a high GII. In patients with a high GII, arteriopathy developed early in CyA treatment. Arteriopathy was observed mostly near embryonic-type glomeruli. Taken together, these glomeruli (surviving embryonic-type, collapsing embryonic-type, and sclerotic glomeruli) essentially equaled the total number of embryonic-type glomeruli in specimens obtained before CyA treatment. CONCLUSION: Our findings indicate a need for caution in CyA therapy for patients with NS, even for a relatively short course of administration, because some patients may have embryonic-type glomeruli or immature arterioles that predispose them to CyA nephropathy.

A patient with Henoch-Schönlein purpura manifesting unusual symptoms and clinical course.

We evaluated and treated a girl with Henoch-Schönlein purpura (HSP), who initially developed redness, swelling, and pain in all 4 limbs accompanied by Raynaud syndrome and then had convulsions and disturbance of consciousness. HSP was diagnosed based on later findings of purpura in both legs and a decrease in factor XIII activity not accompanied by thrombocytopenia. She was normotensive. A skin biopsy specimen showed small-vessel vasculitis accompanied by immunoglobulin A deposition. The cause of erythema and limb pain, convulsions, and disturbed consciousness presumably was vasculitis. The possibility of HSP should be considered in patients with limb pain despite initial absence of purpura and in patients with central nervous system symptoms such as convulsions.

A tubulointerstitial nephritis antigen gene defect causes childhood-onset chronic renal failure.

Tubulointerstitial nephritis antigen (TIN-ag), which has been localized to the renal tubular basement membrane, is a target antigen in some forms of TIN. Physiologically, TIN-ag is thought to be important in maintaining the structure of renal tubular basement membrane. Here we describe a child with chronic renal failure showing a human TIN-ag gene (hTIN-ag) deletion. Immunohistochemical examination using an antihuman TIN-ag monoclonal antibody showed attenuation or lack of TIN-ag staining along the renal tubular basement membrane, whereas nephrocystin staining was normal in renal tubules. Polymerase chain reaction detected no amplification band corresponding to hTIN-ag in this patient. Testing for a deletion in this gene showed nearly complete deletion. By using array-comparative genomic hybridization method, large deletion of a gene mapped on chromosome 6p11-6p12 was demonstrated, corresponding to the locus where hTIN-ag is located. Therefore, an hTIN-ag defect may be a potent cause of end-stage renal failure in childhood.