Eculizumab for paediatric patients with atypical haemolytic uraemic syndrome: full dataset analysis of post-marketing surveillance in Japan.

BACKGROUND: Eculizumab was approved for atypical haemolytic uraemic syndrome (aHUS) in Japan in 2013. Post-marketing surveillance (PMS) was mandated by regulatory authorities to assess the safety and effectiveness of eculizumab in patients with aHUS in a real-world setting. METHODS: Paediatric patients in the PMS cohort who were <18 years of age at the first administration of eculizumab and diagnosed with aHUS [excluding Shiga toxin-producing Escherichia coli HUS, thrombotic thrombocytopaenic purpura and secondary thrombotic microangiopathy (TMA)] were included in the effectiveness and safety analysis. Clinical endpoints of effectiveness [complete TMA response, TMA event-free status, platelet (PLT) count and lactate dehydrogenase (LDH) normalization, serum creatinine (sCr) decrease and estimated glomerular filtration rate (eGFR) improvement] were analysed in patients treated with at least one dose of eculizumab. Serious adverse events (SAEs) were also evaluated. RESULTS: A total of 40 paediatric patients (median age 5 years) were included. The median eculizumab treatment duration was 66 weeks. PLT count, LDH and eGFR significantly improved at 10 days post-treatment. Complete TMA response, haematologic normalization, sCr decrease, eGFR improvement and TMA event-free status were achieved by 73.3%, 73.3%, 70.0%, 78.3% and 77.5% of patients, respectively. Discontinuation criteria were met by 18 patients: 13 patients maintained treatment discontinuation at the end of observation and 5 patients, including 1 patient with aHUS relapse, continued the treatment but extended the treatment interval. During eculizumab treatment, 59 SAEs (0.66/person-year) were reported. Although four deaths were reported, none of them were related to eculizumab. CONCLUSION: Eculizumab was well tolerated and effective for paediatric patients with aHUS in the real-world setting in Japan.

Comprehensive coagulation and fibrinolytic potential in the acute phase of pediatric patients with idiopathic nephrotic syndrome evaluated by whole blood-based rotational thromboelastometry.

BACKGROUND: Venous thromboembolism is a rare, serious complication of idiopathic nephrotic syndrome (INS) in childhood. The mechanisms responsible for the hypercoagulable state in the acute phase of INS are poorly understood, however. This study aimed to assess overall coagulation and fibrinolytic function in pediatric patients with INS. METHODS: Global coagulation and fibrinolysis were examined in whole blood samples from 22 children with initial onset INS (initial-group), 22 children with relapsed INS (relapse-group), and 15 control pediatric patients using rotational thromboelastometry (ROTEM®). In the initial-group, blood samples were obtained before (week 0) and 1-4 weeks after initiation of corticosteroid therapy. EXTEM and FIBTEM were used to assess coagulation and fibrinolysis, respectively. Clot time (CT), clot formation time (CFT), maximum clot firmness (MCF), and α-angle were determined as coagulation parameters, and lysis index at 30 and 60 min (LI30 and LI60, respectively) were assessed as fibrinolytic parameters. RESULTS: CT was significantly shortened, and MCF and α-angle were significantly greater than controls at week 0 and week 1 both in the initial-group and the relapse-group. MCF correlated with serum albumin (r = 0.70, p < 0.001) and fibrinogen level (r = 0.68, p < 0.001). The fibrinolytic parameters (LI30 and LI60) in the initial-group were stable and higher than those in controls at all time points (p < 0.01). CONCLUSIONS: We have shown that the hypofibrinolytic defect did not improve with effective NS treatment at the early 4-week time-point. Additionally, a likely pre-thrombotic state was evident in the period before initial onset and 1 week after corticosteroid therapy in pediatric INS.

Coagulation potential in pediatric patients with immunoglobulin A nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is the most prevalent primary chronic glomerular disease in children. Understanding the changes in coagulability caused by IgAN is important for clarifying pathophysiology and choice of treatment. The coagulation potential in patients with IgAN remains to be investigated, however. We aimed to assess comprehensive coagulation potential in pediatric patients with IgAN and explore its relationship with pathological disease severity. METHODS: Fourteen children with IgAN diagnosed by renal biopsy, who were admitted at Nara Medical University Hospital between 2015 and 2020, were analyzed. Rotational thromboelastometry was used to evaluate coagulation potential. Values of rotational thromboelastometry parameters in patients with IgAN were compared with those in control children. RESULTS: In patients with IgAN (aged median 9.5 year), clotting time plus clot formation time (CT + CFT) was shortened (P = 0.003) and α angle was greater (P < 0.001) than those in controls, indicating a hypercoagulable state. The rate of mesangial hypercellularity of glomeruli correlated with CT + CFT, α, and maximum clot firmness (MCF) (rs = -0.79, 0.56, and 0.37). The rate of cellular/fibrocellular crescent of glomeruli correlated with CT + CFT, α, and MCF (rs = -0.41, 0.60, and 0.50). Patients with mesangial hypercellularity ≥80% of glomeruli showed reduced CT + CFT and increased α angle (P = 0.007 and 0.03). Patients with cellular/fibrocellular crescent ≥10% of glomeruli showed decreased CT + CFT and increased α angle (both P = 0.02). CONCLUSIONS: The hypercoagulable state in pediatric patients with IgAN may be associated with the pathological severity of their disease.

Epidemiology and clinical features of childhood-onset anti-neutrophil cytoplasmic antibody-associated vasculitis: a clinicopathological analysis.

BACKGROUND: This study was performed to determine the clinical features and outcomes of childhood-onset anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), particularly microscopic polyangiitis (MPA). METHODS: A retrospective Japanese multicenter study was performed in patients diagnosed with AAV before 16 years of age. RESULTS: Of 49 patients with AAV, 36 were female. The diagnoses were as follows: MPA (n = 38, 78%), granulomatosis with polyangiitis (GPA; n = 9, 18%), eosinophilic granulomatosis with polyangiitis (EGPA; n = 1, 2%), and other (n = 1, 2%). The median age at onset was 10.7 years, and median time to diagnosis was 2.0 months. Twenty-seven (55%) patients were identified through a school urinary screening program. Initial symptoms included fever and fatigue (45%), and renal (71%), pulmonary (29%), ocular (20%), and mucocutaneous involvement (22%). Although 27 (55%) patients achieved remission and none had died at the last follow-up, at least one recurrence occurred in 13 (48%) patients after a median of 48 months and was more common in patients with GPA (P < 0.01). After a median follow-up of 43 months, seven (14%) patients (all with MPA) progressed to end-stage renal disease (ESRD). CONCLUSIONS: Childhood-onset AAV has an estimated prevalence of 3.41-4.28 per million children and is characterized by female predominance and high frequency of detection in school urinary screening programs. More than 10% of patients with childhood-onset AAV still progress to ESRD without achieving remission. Histological chronicity is a factor associated with ESRD.

Clinically diverse phenotypes and genotypes of patients with branchio-oto-renal syndrome.

Branchio-oto-renal (BOR) syndrome is a rare autosomal dominant disorder characterized by branchiogenic anomalies, hearing loss, and renal anomalies. The aim of this study was to reveal the clinical phenotypes and their causative genes in Japanese BOR patients. Patients clinically diagnosed with BOR syndrome were analyzed by direct sequencing, multiplex ligation-dependent probe amplification (MLPA), array-based comparative genomic hybridization (aCGH), and next-generation sequencing (NGS). We identified the causative genes in 38/51 patients from 26/36 families; EYA1 aberrations were identified in 22 families, SALL1 mutations were identified in two families, and SIX1 mutations and a 22q partial tetrasomy were identified in one family each. All patients identified with causative genes suffered from hearing loss. Second branchial arch anomalies, including a cervical fistula or cyst, preauricular pits, and renal anomalies, were frequently identified (>60%) in patients with EYA1 aberrations. Renal hypodysplasia or unknown-cause renal insufficiency was identified in more than half of patients with EYA1 aberrations. Even within the same family, renal phenotypes often varied substantially. In addition to direct sequencing, MLPA and NGS were useful for the genetic analysis of BOR patients.

EFFICACY OF THE INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE WITH VITRECTOMY FOR RETINAL DETACHMENT ASSOCIATED WITH MYOPIC MACULAR HOLES.

PURPOSE: To evaluate the anatomical and functional outcome of the inverted internal limiting membrane (ILM) flap technique with vitrectomy for retinal detachment associated with macular hole (MHRD) in highly myopic eyes. METHODS: In this retrospective observational study, 21 eyes with MHRD that underwent vitrectomy with conventional ILM peeling (ILM-peeling group, n = 11) or the inverted ILM flap technique (ILM flap group, n = 10) combined with C3F8 tamponade were enrolled in this study. The initial retinal reattachment rate, macular hole closure rate, and postoperative visual acuity at the final visit were compared between the ILM-peeling group and ILM flap group. RESULTS: There was no significant difference in the retinal reattachment rate between ILM-peeling and ILM flap groups (91% and 100%, respectively). The macular hole closure rate in the ILM flap group was 80% (8 of 10 eyes), and was significantly higher than 36% (4 of 11 eyes) in the ILM-peeling group (P = 0.039). Among 12 eyes that achieved macular hole closure, there was no significant difference in median visual acuity after vitrectomy between the ILM flap group and ILM-peeling group (logMAR unit [Snellen acuity]: 1.0 [20/200] and 0.76 [20/125], respectively, P = 0.300). CONCLUSION: Compared with conventional ILM peeling, the inverted ILM flap technique was more effective for macular hole closure after vitrectomy for MHRD in myopic eye but showed no advantage in the postoperative visual outcome in this study.

Specificity of Fur binding to the oxidative stress response gene promoter in the facultative anaerobic archaeon Thermoplasma volcanium.

The genome of the facultative anaerobic thermoacidophilic archaeon Thermoplasma volcanium contains the open-reading frames (ORFs) tvsod and tvogg, which are predicted to encode a putative superoxide dismutase and an 8-oxoguanine DNA glycosylase, respectively. Tvsod is immediately upstream of tvogg, and these two ORFs are aligned in a head-to-tail manner in a single operon. A previous study showed that T. volcanium contains an ORF (TVN0292) encoding the ferric uptake regulator (Fur) and that the T. volcanium Fur protein (TvFur) binds to its own promoter in a metal-dependent manner in vitro. Here, we demonstrated that TvFur also binds to the tvsod-tvogg promoter and determined the TvFur-binding sequences in the tvsod-tvogg promoter by DNaseI footprinting analysis. These results suggest that Fur is required for resistance against reactive oxygen species in this facultative anaerobic archaeon.

Peritoneal dialysis-associated infection caused by Mycobacterium abscessus in a pediatric patient on continuous peritoneal dialysis without switching to hemodialysis.

Most peritoneal dialysis (PD)-associated infections caused by Mycobacterium abscessus (M. abscessus) require a transfer from PD to hemodialysis (HD). Here, we report a pediatric case of exit-site and tunnel infections caused by M. abscessus, for whom PD was continued with catheter replacement, debridement of the infected site, and the administration of multiple antibacterial agents. A 10-year-old boy with end-stage kidney disease secondary to juvenile nephronophthisis with NPHP1 deletion, for whom PD was initiated at the age of 9 years, was admitted to the hospital with complaints of fever, pus at the exit-site of the PD catheter, and poor PD drainage. The dialysis effluent culture results were negative; however, M. abscessus was detected in the pus at the exit-site of the PD catheter. The management of HD was expected to be challenging owing to the presence of developmental disorders. Therefore, PD was continued with the simultaneous removal of the PD catheter, reinsertion of a new catheter at a new site, and debridement of the infected site. Multiple antibacterial therapies were administered for 2 months, and the patient was eventually discharged without switching to HD. To the best of our knowledge, this is the first pediatric case of a PD-associated infection caused by M. abscessus, for whom PD was continued without switching to HD. This treatment strategy is not generally recommended but may be an option for patients without peritonitis who have difficulty switching to HD.

Pediatric mesangial proliferative glomerulonephritis has increased the platelet thrombus formation potentials under high-shear flow condition.

INTRODUCTION: Blood coagulation is associated with glomerulonephritis (GN) pathophysiology. Using whole-blood-based rotational thromboelastometry, we recently reported that the degree of hypercoagulability in pediatric patients with immunoglobulin A nephropathy (IgAN), a GN, might be associated with pathological severity. To further clarify the coagulation status of mesangial proliferative glomerulonephritis (MesPGN), we assessed the platelet thrombus formation (PTF) under high-shear flow using a microchip-based flow chamber system (T-TAS®). METHODS: Thirty-four pediatric patients definitively diagnosed with MesPGN by renal biopsy at Nara Medical University Hospital between 2015 and 2022 were enrolled, and 29 patients (case group; median age, 8.0 years) were assessed. Microchips coated with collagen (PL-chip) were used to assess PTF at high-shear in whole blood. The times to increase by 10 and 30 kPa (T10 and T30) from baseline were calculated and compared with those of the pediatric controls. Changes in the parameters during the treatment course and the relationship between pathological severity and the parameters were evaluated. RESULTS: T10 and T30 parameters in the PL-chip were significantly shorter and the area under the curves were greater in the case group than those in the control group (both p <0.05). Each parameter was enhanced during the 3-week treatment but improved after the end of treatment. No significant relationship was observed between pathological severity and these parameters. Little PTF difference was observed between IgAN and Henoch-Schönlein purpura nephritis. CONCLUSIONS: Pediatric MesPGN increased the potential for PTF under high-shear flow conditions.

Maintenance therapy with mycophenolate mofetil after rituximab in pediatric patients with steroid-dependent nephrotic syndrome.

Rituximab (RTX) has a significant steroid-sparing effect in children with steroid-dependent nephrotic syndrome (SDNS). However, patients are likely to relapse with the recovery of CD20+ cells. We conducted a small prospective cohort study with a historical control to evaluate the effect of RTX infusion followed by mycophenolate mofetil (MMF) as a maintenance therapy. Nine patients with SDNS who stopped their steroid treatment but were treated with MMF after RTX infusion were prospectively observed (group A). Seven patients with SDNS who discontinued steroid and immunosuppressive agents after RTX administration served as a control (group B). During the first year after the administration of RTX, six patients in group A and one patient in group B did not suffer a relapse (p < 0.05). The number of patients who relapsed during the 1 year preceding RTX treatment did not differ between the two groups [4.1 (A) vs. 5.7 (B)], but it was significantly lower in the MMF-treated group 1 year after the RTX treatment [0.4 (A) vs. 2.3 (B), p < 0.005]. The daily amount of prednisolone after the RTX treatment was lower in group A than in group B (0.11 vs. 0.46 mg/kg/day, respectively; p < 0.05). Three patients in group A and five patients in group B relapsed to SDNS and needed additional RTX treatment(s) within 1 year (odds ratio 5.0). Based on these results, we conclude that maintenance therapy with MMF after RTX is a good clinical option.

Anaphylaxis to polyvinylpyrrolidone in povidone-iodine for impetigo contagiosum in a boy with atopic dermatitis.

BACKGROUND: Povidone-iodine (PVP-I) is widely used in antiseptic agents. Immediate allergic reaction to PVP-I preparations is very rare and often overlooked, as it is difficult to diagnose. Polyvinylpyrrolidone (PVP) is thought to play a role in the underlying mechanism. We examined the usefulness of the histamine release test (HRT) for definite diagnosis of PVP allergy. METHOD: A 9-year-old boy with eosinophilia (1,500/microl) and elevated total IgE (1,376 IU/ml) was suspected clinically of having a PVP allergy, as he had anaphylaxis twice when he was administered a PVP-I solution for impetigo contagiosum. Skin prick tests (SPTs) were performed with a PVP-I solution, PVP (K30), gentamicin sulfate and 2 other medicines containing PVP. HRT was assessed using peripheral blood basophils. RESULTS: SPTs to PVP-I solution, PVP-K30 and other medicines were all negative. Histamine release was observed on stimulation by PVP in the presence of autologous serum, although it was not observed in the absence of autologous serum. CONCLUSIONS: This observation was in line with the clinical findings that anaphylaxis had not developed despite the long use of PVP-I solution, but developed only when he received PVP-I solution treatment where basophils could contact PVP-I in the presence of serum, which was probably due to a broken skin and vessel condition. Furthermore, our results suggest the usefulness of HRT in the diagnosis of PVP allergy, and the possibility that negative SPT does not entirely rule out PVP allergy.

Effects of intravitreal injection of tacrolimus (FK506) in experimental uveitis.

PURPOSE: To examine the immunosuppressive and neuroprotective effects of intravitreal injection of tacrolimus in experimental uveitis. METHODS: Tacrolimus (40 microg) was injected intravitreally in rabbits to examine safety. Experimental uveitis was induced in rabbits by systemic immunization with bovine serum albumin (BSA) followed by intravitreal challenge with BSA. On day 1 after BSA challenge, tacrolimus (20 or 40 microg) or betamethasone (400 microg) was injected intravitreally in one eye and balanced salt solution in the contralateral eye. The eyes were evaluated by slit-lamp biomicroscopy, electroretinography, and histopathology. RESULTS: No local or systemic adverse reaction was observed in normal rabbits. In experimental uveitis, intravitreal injection of tacrolimus significantly reduced intraocular inflammation in histopathological analysis (p < 0.03). Amplitudes on the electroretinogram were restored (p < 0.01), and retinal thickness was preserved in tacrolimus-treated eyes (p < 0.03). CONCLUSIONS: In experimental uveitis, intravitreal injection of tacrolimus effectively suppresses ocular inflammation and preserves retinal architecture.

Application of thermo-setting gel as artificial vitreous.

PURPOSE: In this study, we produced a rabbit model and investigated the safety of intravitreous injection of a thermo-setting gel (TG) to determine whether TG can be used as artificial vitreous. METHODS: Ten male Japanese white rabbits were used. After performing vitrectomy in a unilateral eye, we injected 1 ml of WTG-127 into the vitreous cavity. The contralateral control eye was not given ophthalmic solution or surgery. Each eye was examined and intraocular pressure (IOP) and the electroretinogram (ERG) were evaluated. On day 28, all eyes were enucleated and examined. RESULTS: No abnormal findings and no elevation of IOP were observed. On the ERG, no significant difference in the latency and amplitude of either the a wave or b wave was observed. Histopathological examination of the retinal tissue showed no abnormalities. In the presence of a retinal tear, under the detached retina a drift of TG through the tear was observed in a few animals. CONCLUSIONS: In a rabbit model, the safety of using an intravitreous injection of thermo-setting gel as artificial vitreous was confirmed by ophthalmoscopic, electrophysiological, and histological studies for a relatively short observation period. However, TG injection cannot be expected to provide a tamponade effect.

Pharmacokinetics of Carboplatin in a One-Year-Old Anuric Boy Undergoing Hemodialysis and a Review of the Literature.

There have been few reports of carboplatin-based chemotherapy for anuric infants. As we had a chance to treat a one-year-old anuric hepatoblastoma patient with carboplatin, we performed a pharmacokinetic analysis and examined the optimal treatment strategy. A one-year-old anuric boy under peritoneal dialysis was diagnosed with hepatoblastoma. Surgical resection was performed, and administration of carboplatin was scheduled postoperatively aiming at 5 mg·min/mL of the area under the curve from the time of dosing to the time of the last observation (AUC(0-t)). We set the initial dose at 50 mg, higher than that calculated by the Calvert formula (34 mg); the time from the end of carboplatin infusion to the initiation of hemodialysis at 2 h; and the hemodialysis duration at 24 h. The actual AUC0-t was 3.05 mg·min/mL because the elimination half-lives before and during hemodialysis were shorter than expected. The AUC(0-t) after the second dose (100 mg) and the third dose (80 mg) were 7.00 and 4.68 mg·min/mL, respectively. The Calvert formula is not suitable for hemodialysis patients because removal of platinum by hemodialysis is not taken into account. It appears that extrarenal clearance in anuric infants is different from that in adults. We obtained an optimal AUC(0-t) using a dose of 80 mg (200 mg/m(2)), setting the time from the end of carboplatin infusion to the initiation of hemodialysis at 2 h, and performing 8-h hemodialysis. Further accumulation of the pharmacokinetic data of carboplatin is necessary for anuric children.

Early-onset chronic inflammatory disease associated with maternal microchimerism.

Maternal microchimerism (mMc) refers to the presence of a small population of cells originating from the mother. Whether mMc leads to autoimmune responses in children remains controversial. We describe here an 11-year-old boy with persistent fever and elevated levels of C-reactive protein from infancy onward. During infancy, the patient presented with high fever, skin rashes, and hepatic dysfunction. Careful examination including a liver biopsy failed to reveal the cause. At 4 years old, petechiae developed associated with thrombocytopenia and positive anti-dsDNA autoantibodies. Steroid pulse therapy was effective, but the effect of low-dose prednisone was insufficient. At age 9, an extensive differential diagnosis was considered especially for infantile onset autoinflammatory disorders but failed to make a definitive diagnosis. On admission, the patient exhibited short stature, hepatosplenomegaly, generalized superficial lymphadenopathy, and rashes. Laboratory findings revealed anemia, elevated levels of inflammation markers, and hypergammaglobulinemia. Serum complement levels were normal. Serum levels of IL-6 and B-cell activating factor were elevated. Viral infections were not identified. Although HLA typing revealed no noninherited maternal antigens in lymphocytes, female cells were demonstrated in the patient's skin and lymph nodes, suggesting that maternal microchimerism might be involved in the pathogenesis of fever without source in infants.

Transcriptional factor fur from Thermoplasma volcanium binds its own promoter DNA in a divalent cation-dependent manner.

Because archaea possess many respiratory enzymes or radical scavengers with catalytic domains that contain iron, the expression of the genes encoding these enzymes might be regulated by iron acquisition. The genome of an archaeon, Thermoplasma volcanium contains a gene that encodes Fur (TVN0292). The fur gene of T. volcanium was amplified by PCR, and cloned into plasmid pET28a. TvFur (T. volcanium Fur protein) was expressed in E. coli cells and then purified. EMSA revealed that TvFur binds to its own promoter DNA. The binding to its own promoter was in an Mn(2+)-, Zn(2+)-, and Ni(2+)-dependent manner. DNase I footprinting analysis revealed that the binding sequence of tvfur promoter was 5'-G TTATTAT G TTTATAT A TTAATTA G-3'. An analysis utilizing oligonucleotides in TvFur-binding sequences revealed that TvFur binds to the TATA-box or regions in the vicinity of the TATA-box in the promoter. These results indicated that TvFur regulates transcription depending on the availability of environmental divalent cations.

Ecthyma gangrenosum-like lesions in a healthy child after infection treated with antibiotics.

Ecthyma gangrenosum is a cutaneous infection associated most commonly with pseudomonal sepsis in the immunocompromised patient. We describe a previously healthy 4-year-old boy who developed ecthyma gangrenosum-like lesions secondary to antibiotic treatment for possible streptococcal infection. The skin, ears, and extremities were involved. This presentation emphasizes the importance of awareness of the rare complication of ecthyma gangrenosum-like lesions associated with non-Pseudomonas bacterial infection treated with antibiotics, even in a previously healthy child.