Takashi Tateyama

Repeat renal biopsy in a girl with tubulointerstitial nephritis and uveitis syndrome.

Abstract. A Japanese girl aged 8 years who presented with a 2-month history of uveitis subsequently developed tubulointerstitial nephritis. A percutaneous renal biopsy revealed massive interstitial mononuclear cell infiltrates consisting of CD4-positive T cells. Despite administration of topical corticosteroids, the ocular symptoms persisted. Systemic corticosteroid therapy dramatically reduced the ocular symptoms and urinary β2-microglobulin (β 2MG) concentration. However, reducing the prednisolone dosage induced recurrence of uveitis associated with increased levels of urinary β 2MG. The CD4-positive T cell infiltration persisted in the second renal biopsy performed 6 months after the first renal biopsy. These observations suggest that the interstitial cell infiltration persists for a relatively long time in a proportion of patients with tubulointerstitial nephritis and uveitis syndrome (TINU). Although the renal outcome of TINU has been reported to be favorable, prolonged interstitial cell infiltration may affect long-term renal outcome. Selected patients with TINU should be followed with close observation.

Interstitial cystitis and ileus in pediatric-onset systemic lupus erythematosus.

Abstract A girl aged 11 years presented with autoimmune hemolytic anemia with thrombocytopenia, and subsequently developed severe abdominal pain, vomiting, and pollakiuria. X-ray findings of her abdomen demonstrated paralytic ileus with intestinal wall thickening. Intravenous pyelography revealed bilateral hydroureter with mild hydronephrosis and contracted bladder. Pathological examination of her bladder revealed interstitial cystitis, with evidence of focal deposition of IgG and C3 in a granular pattern on small blood vessel walls. She was diagnosed as having systemic lupus erythematosus (SLE) associated with paralytic ileus and chronic interstitial cystitis. Although initiation of high-dose prednisolone therapy resulted in a gradual improvement in clinical symptoms, reducing the dosage of prednisolone caused a relapse. To our knowledge, the combination of paralytic ileus and chronic interstitial cystitis is quite uncommon in pediatric-onset SLE.

Methylprednisolone pulse therapy in Japanese children with severe lupus nephritis

Abstract. Six Japanese children with severe lupus nephritis received prompt initiation of methylprednisolone pulse therapy (MPT). After three courses of MPT, oral prednisolone combined with a 12-week course of oral cyclophosphamide was given and prednisolone was tapered. At presentation, urine protein excretion and histological indices of the mean activity index and the mean chronicity index in the patients were 2.2±1.5 g/day, 10.3±2.0, and 2.8±1.2, respectively. Urine protein excretion and the activity index decreased significantly at the second renal biopsies obtained at a mean interval of 8 months after the first [0.1±0.1 g/day and 3.5±1.4 (P<0.05), respectively], while the chronicity index did not change. At the latest observation (mean interval 53 months), all showed clinical and serological improvement. Complete remission was achieved in two patients, and no patient showed renal impairment. Although this case series is without controls, our treatment protocol may be of benefit to Japanese children with severe lupus nephritis.

Acute tubulointerstitial nephritis associated with piperacillin therapy in a boy with glomerulonephritis

An 11‐year‐old boy with glomerulonephritis developed acute renal failure 4 days after beginning piperacillin (PIPC) treatment. Renal biopsy revealed acute tubulointerstitial nephritis (ATIN) with marked eosinophils. A lymphocyte stimulation test (LST) for PIPC demonstrated an extremely high LST index of 626%. The serum levels of immunoglobulin E and eosinophil cationic protein also showed a significant increase at 9021 IU/mL and greater than 150 μg/L, respectively. These observations suggest that a hypersensitivity reaction might play a role in the pathogenesis of ATIN. This is the first report to describe PIPC‐induced ATIN in a child.

Acute renal failure at the onset of idiopathic nephrotic syndrome in two children

Two children with idiopathic nephrotic syndrome (INS) developed acute renal failure (ARF) at the onset of the disease. Although the initial renal biopsy showed minimal change (MC) lesions with prominent interstitial edema, repeat renal biopsy revealed focal segmental glomerulosclerosis (FSGS). ARF has been reported to be a relatively rare complication in childhood INS. However, the initial manifestation of ARF may increase the risk for subsequent progression to FSGS in a proportion of children with INS with MC lesions.

Senior-Loken syndrome associated with mental retardation and microcephaly

chronic interstitial nephritis leading to end-stage renal failure.1 The clinical hallmarks of NPH are polyuria, polydipsia, anemia, growth retardation and progressive renal failure.1–5 To date, extrarenal manifestations of NPH have been reported to be retinitis pigmentosa (Leber’s congenital amaurosis),1,2,6–9 cerebellar ataxia,1 liver fibrosis,9 thoracic dystrophy4 and cone-shaped epiphyses of the hand.8 Of these, the combination of NPH and Leber’s congenital amaurosis is described as Senior–Loken syndrome (SLS);1,2,6,8,9 however, the occurence of SLS is thought to be relatively rare,6 especially in Japan. We encountered a Japanese girl who presented with anemia, severe mental retardation, microcephaly, growth retardation, metabolic acidosis and renal insufficiency. She was diagnosed as having SLS.

Contribution of macromolecular IgA1 to IgA abnormality in IgA nephropathy

Abstract To evaluate the contribution of macromolecular IgA1 to IgA abnormality in childhood IgA nephropathy, serum samples from 29 healthy children and 26 patients with IgA nephropathy in different age-groups (7–9, 10–12, and 13–15 years) were each separated by sucrose density gradient ultracentrifugation and assayed for IgA1 using an enzyme-linked immunosorbent assay. IgA1 in fraction I (sedimentation coefficient >11.4s) was significantly greater in patients 7–15 years of age (median 36.3–57.0 mg/dl) than in the age-matched controls (median 8.8–10.4 mg/dl). IgA1 in fraction II (11.4–9.3s) was significantly greater in patients 10–15 years of age (median 46.7–52.6 mg/dl) than in the controls (median 27.8–35.5 mg/dl), and IgA1 in fraction III (<9.3s) was significantly greater in patients 13–15 years of age (median 156.9 mg/dl) than in the controls (median 120.7 mg/dl). The ratio of IgA1 in fractions I–III was higher in the patients of each age-group (median 0.233–0.314) than in the controls (median 0.067–0.082), while the ratio of IgA1 in fractions II–III was not significantly high in patients 7–12 years old (median 0.268 to 0.318) compared with the controls (median 0.182–0.264). Thus, IgA abnormality in childhood IgA nephropathy would be better represented by an increase in macromolecular IgA1 of >11.4s than by an increase in IgA1 in fractions of 11.4–9.3s or <9.3s.

Sequential measurement of mesangial matrix area occupying the glomerulus in children with IgA nephropathy

BackgroundIgA nephropathy is the most common form of primary glomerulonephropathy in children it has a variable clinical course, from spontaneous remission to progression to renal death. It has been reported that predominant mesangial hypercellularity is characteristic of early lesions, and that it changes to a gradual matricial increase, with sclerosis, according to the disease progression.MethodsA sequential measurement of the ratio of mesangial matrix area to glomerular area (M/G) was done in 5 children with moderately proteinuric IgA nephropathy, who underwent 3 consecutive, repeat renal biopsies. A prompt initiation of alternate-day prednisolone therapy (an initial dosage at 1 mg/kg, maximum 60 mg) after the first renal biopsy was done in 4 cases. The remaining patient received this therapy after the second renal biopsy.ResultsA sequential measurement of the M/G in the former cases did not show an increase between the biopsies, while measurement of the latter one showed a progressive increase. Moreover, the case that had an increase in the M/G showed renal impairment at the third biopsy.ConclusionAlthough a small number of cases were examined, a sequential measurement of the M/G in children with moderately proteinuric IgA nephropathy may be a valuable indicator for a more precise evaluation of clinical outcome in a clinical setting.