Post-transplant Schizophyllum commune abscess in a pediatric patient with chronic granulomatous disease.

Schizophyllum commune is a widely distributed basidiomycete fungus that occasionally causes sinusitis or allergic bronchopulmonary mycosis. The invasive infection mostly occurs in immunocompromised adults. The number of reports on S. commune infection have increased in this decade due to the expansion of diagnostic techniques and awareness in clinical practice. However, S.commune infection in patients with primary immunodeficiencies has not been reported yet. Here, we described S. commune-abscesses developed in the brain and lung of a boy with chronic granulomatous disease (CGD) after allogenic hematopoietic cell transplantation (HCT). A 12-year-old CGD patient developed febrile neutropenia from day 4 after HCT, followed by chest pain on day 23. He had no obvious infection before HCT. Diagnostic imaging revealed disseminated lung and brain abscesses. He received administration of voriconazole, and his symptoms improved after engraftment. Chronic administration of voriconazole had also a favorable therapeutic response to brain lesion. A part of the fungus ball exhaled by the patient was cultured to develop a filamentous fungus. S. commune was identified by the analysis of the 28S rRNA gene. The catalase test was positive for S. commune, indicating that S. commune had virulence in this patient with CGD. The assessment of specific-IgG to S. commune suggested peri-transplant infection, although colonization was not excluded. This rare pediatric case of S. commune infection highlights that CGD patients are vulnerable to invasive infection, especially when undergoing HCT.

Critical vitamin deficiencies in autism spectrum disorder: Reversible and irreversible outcomes.

Vitamin deficiencies are an emerging concern in the management of children with autism spectrum disorder (ASD). Particular attention is required for recognizing the variable signs caused by unbalanced food intakes. We herein report two patients with multiple vitamin deficiencies who needed critical care showing different prognoses. Patient 1 with 'Shoshin' beriberi presenting with cardiac arrest had thiamine deficiency developed severe neurological sequelae despite rapid vitamin supplementation. Patient 2, who had leg pain and a limping gait, showed a rapid recovery with intravenous infusion and tube feeding after being diagnosed with scurvy. A literature search revealed several children with ASD with critically ill thiamine deficiency, but few reports documented a life-threatening condition in the form of cardiac arrest at the onset. Considering the high observation rate of food selectivity in children with ASD, early intervention is required to prevent the exacerbation of vitamin deficiencies to severe neurological disabilities.

Efficient human-like antibody repertoire and hybridoma production in trans-chromosomic mice carrying megabase-sized human immunoglobulin loci.

Trans-chromosomic (Tc) mice carrying mini-chromosomes with megabase-sized human immunoglobulin (Ig) loci have contributed to the development of fully human therapeutic monoclonal antibodies, but mitotic instability of human mini-chromosomes in mice may limit the efficiency of hybridoma production. Here, we establish human antibody-producing Tc mice (TC-mAb mice) that stably maintain a mouse-derived, engineered chromosome containing the entire human Ig heavy and kappa chain loci in a mouse Ig-knockout background. Comprehensive, high-throughput DNA sequencing shows that the human Ig repertoire, including variable gene usage, is well recapitulated in TC-mAb mice. Despite slightly altered B cell development and a delayed immune response, TC-mAb mice have more subsets of antigen-specific plasmablast and plasma cells than wild-type mice, leading to efficient hybridoma production. Our results thus suggest that TC-mAb mice offer a valuable platform for obtaining fully human therapeutic antibodies, and a useful model for elucidating the regulation of human Ig repertoire formation.

Progressive B cell depletion in human MALT1 deficiency.

Mucosa-associated lymphoid tissue lymphoma-translocation gene 1 (MALT1)-deficiency is a rare combined immunodeficiency characterized by recurrent infections, dermatitis and enteropathy. We herein investigate the immunological profiles of our patient and previously reported children with MALT1-deficiency. A mutation analysis was performed by targeted panel sequencing for primary immunodeficiency. Lymphocyte subset, activation and B cell differentiation were analyzed by flow cytometry and t-distributed stochastic neighbor embedding. Pneumocystis pneumonia developed in a 6-month-old Japanese infant with atopic dermatitis, enteritis and growth restriction. This infant showed agammaglobulinemia without lymphopenia. At 8 years of age, the genetic diagnosis of MALT1-deficiency was confirmed on a novel homozygous mutation of c.1102G>T, p.E368X. T cell stimulation tests showed impairments in the production of interleukin-2, phosphorylation of nuclear factor kappa B (NF-κB) p65 and differentiation of B cells. In combination with the literature data, we found that the number of circulatory B cells, but not T cells, were inversely correlated with the age of patients. The hematopoietic cell transplantation (HCT) successfully reconstituted the differentiation of mature B cells and T cells. These data conceptualize that patients with complete MALT1-deficiency show aberrant differentiation and depletion of B cells. The early diagnosis and HCT lead to a cure of the disease phenotype associated with the loss-of-function mutations in human CARD11.

Brain-sparing cord blood transplantation for the borderline stage of adrenoleukodystrophy.

BACKGROUND: Adrenoleukodystrophy (ALD) is an X-linked disorder characterized by rapidly progressive deterioration of neurocognitive functions and premature death. In addition to the difficulty in identifying the earliest signs of ALD, treatment-associated exacerbation of neurological symptoms has been an obstacle to achieve successful hematopoietic cell transplantation (HCT) for affected children. CASE REPORT: We report a 9-year-boy with ALD. He presented with impairment in social skills compatible to the diagnosis of autism spectrum disorder from 3 years of age. He showed progressive strabismus, slurred speech and dysmetria at 6 years of age. The head MRI showed symmetrical T2-hyperintense lesions in the occipital white matters with a gadolinium enhancement, which extended to the internal capsules. The Loes score was thus calculated as 13. Very-long-chain-fatty-acids were increased to 1.800 (C24:0/C22:0) and 0.077 (C26:0/C22:0) in leukocytes. Sanger sequencing confirmed the pathogenic variant in ABCD1 (NM_000033.4:p.Gly512Ser). After multidisciplinary discussions over the treatment options, we performed a cord blood HCT with a reduced intensity conditioning (fludarabine, melphalan and brain-sparing total body irradiation). He was fully recovered with >90% chimerism of donor leukocytes at 55 days after HCT. He experienced three times of generalized seizures after discharge, that has been well controlled for 2 years without other complications or neurocognitive deteriorations. CONCLUSION: For patients with ALD on a borderline indication for HCT, brain-sparing irradiation might be an alternative option in reduced intensity conditioning. Careful decision-making process and tailored conditioning are critical for the successful outcome of HCT for children with ALD.

Cytomegalovirus-Associated Hemolytic Anemia in an Infant Born to a Mother with Lupus.

A 31-day-old infant was admitted to the pediatric intensive care unit due to shock and anemia. The mother had systemic lupus erythematosus and direct antiglobulin test (DAT)-positive hemolytic anemia. The perinatal course of this infant and the mother was uneventful. Regular health check screenings revealed that activity, growth, and development were unremarkable at birth, 5, and 28 days of life. Passive immune hemolytic anemia due to neonatal lupus erythematosus was diagnosed based on a positive DAT for warm-type IgG antibodies, reticulocytosis, and lupus-specific antibodies at rehospitalization. It was complicated by cytomegalovirus (CMV) antigenemia. Umbilical cord blood and peripheral blood samples obtained from the infant at 5 days after birth were negative for CMV DNA. The infant was curatively treated by intensive care with repeated blood transfusions and antiviral therapy. This is the first report indicating that CMV infection exacerbates hemolytic anemia in patients with maternal red blood cell alloantibodies.

Acute isolated Aspergillus appendicitis in pediatric leukemia.

Aspergillus is a widespread fungus in the environment, usually invades through the respiratory tract. Invasive aspergillosis is a fatal disseminated infection in immunocompromised hosts. Appendicitis occurs scarcely in patients with leukemia. We report a case of Aspergillus appendicitis that underwent an urgent appendectomy. An 11-year-old boy received the diagnosis of acute myeloid leukemia, because of the bone pain and results of the bone marrow study. He obtained a complete remission after cancer chemotherapy and received peripheral blood stem cell transplantation from a histocompatible sibling. Leukemia relapsed 5 months post-transplant. Induction therapy with etoposide, cytarabine and mitoxantrone was started on Candida prophylaxis. Fifteen days after the end of chemotherapy, he presented with febrile neutropenia and abdominal pain, that did not respond to broad-spectrum antibiotics. Serum levels of C-reactive protein, ß-D-glucan and procalcitonin were unremarkable. Computed tomography scan revealed a swollen appendix and the adjacent tissue inflammation. An urgent appendectomy led to a tentative diagnosis of Aspergillus appendicitis based on the histopathological findings of many fungal hyphal forms. Panfungal polymerase chain reaction using DNA extracted from the lesion determined the pathogen of Aspergillus niger. There was no evidence of invasive aspergillosis. During the prolonged anti-fungal therapy, he achieved a remission of leukemia and underwent the second hematopoietic cell transplantation. To our knowledge, Aspergillus appendicitis was reported to occur in 5 leukemia patients. Four of them survived after appendectomy and one died from intestinal perforation. Early surgical intervention is mandatory for a cure of Aspergillus appendicitis in neutropenic patients on Candida prophylaxis.