Akane Izu

A boy with IgA nephropathy complicated by tubulointerstitial nephritis and uveitis (TINU) syndrome.

BACKGROUND Abnormal cellular and humoral immunity underlie both immunoglobulin A (IgA) nephropathy and tubulointerstitial nephritis and uveitis (TINU) syndrome. We encountered a teenage boy who developed TINU syndrome during the course of IgA nephropathy. CASE REPORT 1 year after onset of IgA nephropathy following acute enteritis, a 14-year-old boy again experienced acute enteritis caused by Campylobacter jejuni, which was followed by TINU syndrome with prominent low-molecular-weight proteinuria. Renal histologic examination showed T-cell-dominant tubulointerstitial infiltration of marked immune cells including CD54-positive cells. Steroid therapy improved renal function, reversing aggravation of IgA nephropathy by TINU syndrome. CONCLUSIONS The boys human leukocyte antigen profile suggested predisposition to these two diseases, triggered by which were intestinal infections. The enteritis probably induced abnormalities in cellular and humoral immunity. Low-molecular-weight proteinuria, which reflected our patients tubulointerstitial lesions, should call for consideration of TINU syndrome, including ophthalmologic assessment for possible uveitis.

Childhood Cogan syndrome with aortitis and anti-neutrophil cytoplasmic antibody-associated glomerulonephritis.

Cogan syndrome is a systemic disease manifesting interstitial keratitis, sensorineural hearing loss, tinnitus, and rotatory vertigo. Renal complications of this syndrome are very rare. We encountered an adolescent with Cogan syndrome complicated by aortitis and anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis. At the age of 14, the patient showed proteinuria in a screening urinalysis at school and was found to lack a right radial pulse. Magnetic resonance angiography disclosed right subclavian artery stenosis. Examination of a renal biopsy specimen showed ANCA-positive crescentic glomerulonephritis. Steroid and immunosuppressant treatment improved renal function and histopathology, but repeated recurrences followed. At 18, the patient developed rotatory vertigo, a sense of ear fullness, and sensorineural hearing loss. The patient was diagnosed with Cogan syndrome. We know of no previous description of ANCA-positive crescentic glomerulonephritis in children with Cogan syndrome. Accordingly, evaluation of aortitis in childhood should include not only otolaryngologic and ophthalmologic examinations, but also periodic urine examination and renal function tests.

Guillain-Barré Syndrome and Crohn disease: A Case Report

Development of both Crohn disease and Guillain-Barré syndrome likely involves autoimmunity associated with excessive inflammatory cytokines. We treated a girl who developed Guillain-Barré syndrome during the course of Crohn disease. Although high-dose γ-globulin therapy administered initially for Guillain-Barré syndrome was ineffective, plasmapheresis ameliorated her acute neuropathic symptoms. Crohn disease was managed with Salazopyrin administration and enteral feeding. Chronic inflammation of the intestinal mucosa caused by Crohn disease can allow presentation of microbial intestinal antigens normally hidden from the immune system. Such presentation could incite an extraintestinal immune response on the basis of molecular mimicry, leading to activation of systemic autoimmunity against the nervous system. Accordingly, concurrence of Guillain-Barré syndrome and Crohn disease in our patient appeared to result from shared autoimmune mechanisms and systemic and local increases in cytokine concentrations. The patient also developed erythema nodosum and gall stones, relatively common complications of Crohn disease. However, Guillain-Barré syndrome is rare.

Intravitreal Injection of Bevacizumab for Retinopathy of Prematurity in an Infant with Peters Anomaly

Purpose: To report our findings in an infant with Peters anomaly type II whose retinopathy of prematurity (ROP) was treated with an anti-VEGF agent and surgeries. Case Report: A male infant weighing 548 g was born prematurely at 23 weeks and 1 day with corneal opacity and shallow anterior chambers in both eyes. At the postmenstrual age of 35 weeks and 3 days, the infant was tentatively diagnosed with stage 3 ROP because of a dilated tunica vasculosa lentis and ultrasonographic findings. The boy was treated with bilateral intravitreal injections of bevacizumab (IVB) because laser photocoagulation of the retina could not be performed due to the corneal opacity. The retina in the right eye detached 3 times, namely 5 days, 16 days, and 7 months after the IVB; encircling the scleral buckle and a vitrectomy with endolaser photocoagulation were therefore required. In his left eye, the retina was reattached after the initial IVB, and no additional treatment was required. ROP was not reactivated in both eyes until the last examination at the age of 2 years and 6 months. Conclusions: Our results showed that IVB is a useful treatment for ROP in patients with Peters anomaly. However, a retinal detachment can be a complication after IVB. The optimal timing of IVB for ROP in infants with hazy media needs to be determined.

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

BackgroundSecondary 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.MethodsWe encountered two patients with a nonfunctioning ECT2 genotype who later developed FSGS. Both developed proteinuria associated with acute renal failure in early childhood.ResultsRenal 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.ConclusionsECT2 is important for tight junction function and maintenance of cell polarity. Nonfunction of this gene may cause renal tubulointerstitial injury, progressing to glomerular sclerosis.

Focal segmental glomerulosclerosis and partial deletion of chromosome 6p: a case report

We treated a patient with 6p partial deletion syndrome diagnosed after proteinuria was detected during developmental examination 3 years after birth. External anomalies included ocular hypertelorism, saddle nose, elongated philtrum, tent-like lips, and low-set auricles. Mental retardation was evident. The karyotype was 46,XX,del(6) (p.22.1-p22.3) with an interstitial deletion. The kidneys showed no abnormality on imaging such as hydronephrosis, atrophy, or malformation. Examination of a renal biopsy specimen disclosed focal segmental glomerulosclerosis. No cardiac anomaly or Rieger anomaly, which often are present in this syndrome, were noted.

Non-invasive renal artery embolization for renal dysplasia accompanied by hypertension

Renovascular hypertension caused by renal dysplasia often is resistant to drug therapy. For a 14‐year‐old girl with such refractory hypertension, a non‐invasive right renal ablation by embolization with anhydrous ethanol using a shepherd ‘s‐crook’ balloon catheter, was done. Blood pressure then rapidly normalized. Apart from mild fever after the procedure, no adverse effects occurred. In patients with mild renal artery stenosis and hypertension resistant to anti‐hypertensive drug therapy, renal artery embolization may be a useful option.