Unilateral nephrectomy for young infants with congenital nephrotic syndrome of the Finnish type.

BACKGROUND: The management of congenital nephrotic syndrome of the Finnish type (CNF) is challenging. It is difficult to withdraw intravenous albumin infusions, resulting in long-term hospitalization. In addition, fatal hypotension after bilateral nephrectomy has been reported. In our center, we have performed unilateral nephrectomy during early infancy. METHODS: Infants diagnosed with CNF between 2011 and 2020 in our institution were enrolled. We examined the clinical course before and after unilateral nephrectomy and evaluated the effectiveness of this strategy. RESULTS: Seven patients (all showing NPHS1 mutations) were enrolled. All required daily intravenous albumin infusion via central venous catheter (CVC). Unilateral nephrectomy was performed at a median of 76 days of age (59-208 days). Surgical complications did not occur in any of patients. The mean albumin dose was decreased after unilateral nephrectomy (2.0 vs 0.4 g/kg/day; p = 0.02). Intravenous albumin infusion could be withdrawn at a median of 17 days, the CVC removed at a median of 21 days, and they discharged at a median of 82 days after unilateral nephrectomy. Although bacterial infections were noted seven times before unilateral nephrectomy, only one episode occurred after surgery. Four patients initiated peritoneal dialysis at two to three years of age and all of them underwent kidney transplantation thereafter. CONCLUSIONS: Unilateral nephrectomy during early infancy may be an effective treatment allowing for withdrawal from albumin infusion, prevention of complications, withdrawal from CVCs and shortening hospital stay for patients with CNF.

Eosinophilic peritonitis in children on chronic peritoneal dialysis.

BACKGROUND: Eosinophilic peritonitis (EP) is sometimes difficult to distinguish from bacterial peritonitis (BP) at onset, as they are often overlapping. Previous reports show EP occurs more frequently in infants, although the reason is unknown. METHODS: The study population was 77 pediatric patients receiving chronic peritoneal dialysis (PD) in our center. We compared clinical and laboratory data at onset of EP with those of BP. We also investigated age distribution at onset of EP and PD-related surgery. RESULTS: Eleven patients developed EP (18 episodes) and 19 patients developed BP (38 episodes). EP patients showed lower rate of cloudy dialysate (44.4% vs. 74.4%; p = 0.04), lower rate of fever (38.9% vs. 56.4%), lower frequency of abdominal pain (16.7% vs. 38.5%), higher peripheral blood eosinophil counts (/µL) (514 vs. 160; p < 0.001), and lower serum C-reactive protein level (mg/dL) (0.4 vs. 4.7; p < 0.001) than BP patients. Thirteen EP events were observed after 169 surgical interventions. Age at surgery-related EP was similar to age at surgery without EP (2.6 vs. 2.1; p = 0.65). There was no significant difference in postoperative EP occurrence between groups <2 years and ≥ 2 years (6.2% vs. 9.1%; p = 0.48). However, infants received more operations than older children. CONCLUSION: Clinical symptoms in children and laboratory data of EP in children were less severe than those of BP. As incidence of postoperative EP did not differ by age, we speculate that higher incidence of EP in infants might be associated with higher incidence of surgery, although further validation is necessary.

Refractory Hypertension in Infantile-Onset Denys-Drash Syndrome.

Denys-Drash syndrome is characterized by progressive nephropathy, gonadal dysgenesis, and Wilms tumor caused by a WT1 gene mutation. Infants with Denys-Drash syndrome frequently experience severe hypertension, but detailed clinical manifestations have yet to be clarified. Cases of infantile-onset Denys-Drash syndrome with severe hypertension at our hospital were retrospectively analyzed and the pathogenesis of hypertension was investigated. Six infants who received the diagnosis of Denys-Drash syndrome at the median age of 10 days (range: 2-182 days) were enrolled. Five infants had the complication of severe hypertension within a few days of diagnosis. All the patients showed rapid progression to end-stage renal disease and urgently required dialysis due to anuria/oliguria and hypervolemia with a median duration of 7.5 days (range: 0-17 days) on the day after diagnosis. Even under dialysis, all the patients continued to need antihypertensive treatment. Five patients underwent a preventive nephrectomy for Wilms tumor, and one patient underwent a nephrectomy due to progression to Wilms tumor. Two patients developed hypotension after a nephrectomy. The main causes of hypertension were hypervolemia in the predialysis stage, renin-associated hypertension in the dialysis stage, and multiple factors, including increased plasma catecholamine-associated hypertension in the postnephrectomy dialysis stage. At last the follow-up after bilateral nephrectomy, four of the five patients required antihypertensive treatment. Not all the patients showed target organ complications caused by hypertension. Severe hypertension is a common complication of infantile-onset Denys-Drash syndrome. The possibility of hypotension after nephrectomy should be considered in patients with Denys-Drash syndrome.

Hematopoietic stem cell transplantation for progressive combined immunodeficiency and lymphoproliferation in patients with activated phosphatidylinositol-3-OH kinase δ syndrome type 1.

BACKGROUND: Activated phosphatidylinositol-3-OH kinase δ syndrome type 1 (APDS1) is a recently described primary immunodeficiency syndrome characterized by recurrent respiratory tract infections, lymphoid hyperplasia, and Herpesviridae infections caused by germline gain-of-function mutations of PIK3CD. Hematopoietic stem cell transplantation (HSCT) can be considered to ameliorate progressive immunodeficiency and associated malignancy, but appropriate indications, methods, and outcomes of HSCT for APDS1 remain undefined. OBJECTIVE: Our objective was to analyze the clinical manifestations, laboratory findings, prognosis, and treatment of APDS1 and explore appropriate indications and methods of HSCT. METHODS: We reviewed retrospectively the medical records of cohorts undergoing HSCT at collaborating facilities. RESULTS: Thirty-year overall survival was 86.1%, but event-free survival was 39.6%. Life-threatening events, such as severe infections or lymphoproliferation, were frequent in childhood and adolescence and were common indications for HSCT. Nine patients underwent HSCT with fludarabine-based reduced-intensity conditioning. Seven patients survived after frequent adverse complications and engraftment failure. Most symptoms improved after HSCT. CONCLUSION: Patients with APDS1 showed variable clinical manifestations. Life-threatening progressive combined immunodeficiency and massive lymphoproliferation were common indications for HSCT. Fludarabine-based reduced-intensity conditioning-HSCT ameliorated clinical symptoms, but transplantation-related complications were frequent, including graft failure.

RAG1 deficiency may present clinically as selective IgA deficiency.

BACKGROUND: Recombination-activating gene (RAG) 1 and 2 deficiency is seen in patients with severe combined immunodeficiency (SCID) and Omenn syndrome. However, the spectrum of the disease has recently expanded to include a milder phenotype. OBJECTIVE: We analyzed a 4-year-old boy who was initially given the diagnosis of selective immunoglobulin A deficiency (SIgAD) based on immunoglobulin serum levels without any opportunistic infections, rashes, hepatosplenomegaly, autoimmunity or granulomas. The patient was found to be infected with varicella zoster; however, the clinical course was not serious. He produced antiviral antibodies. METHODS: We performed lymphocyte phenotyping, quantification of T cell receptor excision circles (TRECs) and kappa deleting recombination excision circles (KRECs), an analysis of target sequences of RAG1 and 2, a whole-genome SNP array, an in vitro V(D)J recombination assay, a spectratype analysis of the CDR3 region and a flow cytometric analysis of the bone marrow. RESULTS: Lymphocyte phenotyping demonstrated that the ratio of CD4+ to CD8+ T cells was inverted and the majority of CD4+T cells expressed CD45RO antigens in addition to the almost complete lack of B cells. Furthermore, both TRECs and KRECs were absent. Targeted DNA sequencing and SNP array revealed that the patient carried a deletion of RAG1 and RAG2 genes on the paternally-derived chromosome 11, and two maternally-derived novel RAG1 missense mutations (E455K, R764H). In vitro analysis of recombination activity showed that both RAG1 mutant proteins had low, but residual function. CONCLUSIONS: The current case further expands the phenotypic spectrum of mild presentations of RAG deficiency, and suggests that TRECs and KRECs are useful markers for detecting hidden severe, as well as mild, cases.

Multicenter experience in hematopoietic stem cell transplantation for serious complications of common variable immunodeficiency.

BACKGROUND: Common variable immunodeficiency (CVID) is usually well controlled with immunoglobulin substitution and immunomodulatory drugs. A subgroup of patients has a complicated disease course with high mortality. For these patients, investigation of more invasive, potentially curative treatments, such as allogeneic hematopoietic stem cell transplantation (HSCT), is warranted. OBJECTIVE: We sought to define the outcomes of HSCT for patients with CVID. METHODS: Retrospective data were collected from 14 centers worldwide on patients with CVID receiving HSCT between 1993 and 2012. RESULTS: Twenty-five patients with CVID, which was defined according to international criteria, aged 8 to 50 years at the time of transplantation were included in the study. The indication for HSCT was immunologic dysregulation in the majority of patients. The overall survival rate was 48%, and the survival rate for patients undergoing transplantation for lymphoma was 83%. The major causes of death were treatment-refractory graft-versus-host disease accompanied by poor immune reconstitution and infectious complications. Immunoglobulin substitution was stopped in 50% of surviving patients. In 92% of surviving patients, the condition constituting the indication for HSCT resolved. CONCLUSION: This multicenter study demonstrated that HSCT in patients with CVID was beneficial in most surviving patients; however, there was a high mortality associated with the procedure. Therefore this therapeutic approach should only be considered in carefully selected patients in whom there has been extensive characterization of the immunologic and/or genetic defect underlying the CVID diagnosis. Criteria for patient selection, refinement of the transplantation protocol, and timing are needed for an improved outcome.

Clinical profile and genetic basis of Wiskott-Aldrich syndrome at Chandigarh, North India.

BACKGROUND: The Wiskott-Aldrich syndrome (WAS) is a rare X-linked immunodeficiency disorder characterized by thrombocytopenia with small sized platelets, eczema, and recurrent infections. There is paucity of information on WAS from the Indian subcontinent. We describe the clinical and molecular profile of 8 patients with WAS as seen in the Pediatric Immunodeficiency Clinic at the Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India. METHODS: A detailed analysis of the clinical profiles, investigations and outcome of the 8 children diagnosed with WAS during the period 2006- 2010 was performed. Confirmation of the genetic diagnosis was done at the Service d'Hématologie, d'Immunologie et de Cytogénétique, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France and the National Defense Medical College, Saitama, Japan. RESULTS: 8 patients were diagnosed as WAS in 5 years. The ages at diagnosis ranged from 13 weeks to 9 years while the mean age of onset of the symptoms was 117 days +/- 136 days. The diagnosis was established within a mean period of 31 months (ranging 1-108 months) from the onset of symptoms. Recurrent infections and diarrhea were seen in 6 and 7 out of the 8 patients, respectively, while eczema was variable. Autoimmunity manifestations were observed in 2 children. Thrombocytopenia and small platelet size was the hallmark of the disease and the main clinical clue to diagnosis in our patients. Mutations in the WASP gene were seen in 8 children, out of which 2 were novel mutations. While one child successfully underwent bone marrow transplantation, two children are doing well on immunoglobulin replacement and cotrimoxazole prophylaxis. Out of 8 children 4 children in our cohort died--all had high WAS scores and could not be offered hematopoietic stem cell transplantation. CONCLUSION: WAS should be suspected clinically in any male infant with persistent unexplained thrombocytopenia and especially if the platelet size is small. Clinical presentation can be very variable and it is therefore important to recognize the entire spectrum of the disease. Understanding the molecular basis has important implications for the diagnosis, treatment, and genetic counseling of patients with WAS.

Delayed onset adenosine deaminase deficiency associated with acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM) is a monophasic, immune-mediated demyelinating disorder that can appear after either immunizations or, more often, infections. Magnetic resonance imaging of patients shows inflammatory lesions in the brain and spinal cord. An immune-mediated mechanism may play a role in this disease, although its precise pathogenesis remains unclear. In this study, a 2-year-old boy presented with ADEM, and he showed improvement on treatment with high-dose intravenous corticosteroids. At the age of 3 years, the presence of recurrent bronchitis, bronchiectasia, and lymphopenia suggested that the patient was suffering from combined immunodeficiency. The patient was finally diagnosed with delayed onset adenosine deaminase deficiency. Delayed onset adenosine deaminase deficiency is frequently associated with autoimmune diseases, including thyroiditis and cytopenia, both of which were observed in the patient. The ADEM in this patient may be a presentation of delayed onset adenosine deaminase deficiency.