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Rev Neurol (Paris). 2023 Dec 1:S0035-3787(23)01116-5. doi: 10.1016/j.neurol.2023.08.021. Online ahead of print.

ABSTRACT

BACKGROUND: Primary central nervous system lymphoma (PCNSL) accounts for less than 5% of primary brain tumors. Epileptic seizures are a common manifestation of brain tumors; however, literature on the prevalence, characteristics, and oncological implications of seizures in patients with PCNSL is limited, and the management of antiepileptic drugs (AEDs) is unclear. This review aimed to summarize the existing knowledge on seizures in PCNSL, their potential association with surgery, oncological treatment, survival rates, and management of AEDs.

METHODS: A systematic review was performed according to the PRISMA recommendations and included articles published between 1953 and 2023 describing seizures in patients with PCNSL.

RESULTS: The search identified 282 studies, of which 21 were included. Up to 33% of patients with PCNSL developed seizures, mostly at the initial presentation. Little information was found on changes in seizure incidence through the course of the disease, and no details were found on seizure frequency, the percentage of treatment-resistant patients, or the evolution of seizures at remission. Younger age, cortical location, and immunodeficiency have been identified as potential risk factors for seizures, but evidence is very limited. The growing use of vigorous treatments including intensive chemotherapy with autologous stem cell transplantation and immunotherapy with CAR-T cells is associated with a higher incidence of seizures. The association between seizure development and patient mortality in PCNSL remains unknown. There are no data on AED prophylaxis or the use of specific AEDs in PCNSL.

CONCLUSIONS: Further studies are needed to investigate seizures in larger cohorts of PCNSL, to clarify their prevalence, better characterize them, identify risk factors, analyze survival rates, and make recommendations on AED management. We recommend following general practice guidelines for seizures symptomatic of brain tumors and not to prescribe AED prophylaxis in PCNSL.

PMID:38042665 | DOI:10.1016/j.neurol.2023.08.021

Am J Med Genet A. 2023 Dec 1. doi: 10.1002/ajmg.a.63486. Online ahead of print.

ABSTRACT

Aicardi-Goutières syndrome (AGS) is an autosomal recessive inflammatory syndrome that manifests as an early-onset encephalopathy with both neurologic and extraneurologic clinical findings. AGS has been associated with pathogenic variants in nine genes: TREX1, RNASEH2B, RNASEH2C, RNASEH2A, SAMHD1, ADAR, IFIH1, LSM11, and RNU7-1. Diagnosis is established by clinical findings (encephalopathy and acquired microcephaly, intellectual and physical impairments, dystonia, hepatosplenomegaly, sterile pyrexia, and/or chilblains), characteristic abnormalities on cranial CT (calcification of the basal ganglia and white matter) and MRI (leukodystrophic changes), or the identification of pathogenic/likely pathogenic variants in the known genes. One of the genes associated with AGS, SAMHD1, has also been associated with a spectrum of cerebrovascular diseases, including moyamoya disease (MMD). In this report, we describe a 31-year-old male referred to genetics for MMD since childhood who lacked the hallmark features of AGS patients but was found to have compound heterozygous SAMHD1 variants. He later developed mitral valve insufficiency due to recurrent chordal rupture and ultimately underwent a heart transplant at 37 years of age. Thus, these data suggest that SAMHD1 pathogenic variants can cause MMD without typical AGS symptoms and support that SAMHD1 should be assessed in MMD patients even in the absence of AGS features.

PMID:38041217 | DOI:10.1002/ajmg.a.63486

Clin Immunol. 2023 Nov 28:109855. doi: 10.1016/j.clim.2023.109855. Online ahead of print.

ABSTRACT

We characterized a family diagnosed with immunodeficiency disease presenting with low immunoglobulin levels and skin dyskeratosis. Exome sequencing revealed compound heterozygous missense variants in SLC5A6, the gene encoding a cellular sodium-dependent multivitamin transporter (SMVT) responsible for transporting vitamins, including biotin (vitamin B7). We showed that the biotin deficiency was caused by the SLC5A6 variants resulting in defective B cell differentiation and antibody deficiency. Altered cellular metabolic profiles, including aberrant mitochondrial respiration and reliance on glycolysis, may underlie the failure in plasma cell maturation. Replenishment of biotin improved plasma cell maturation and recovered the antibody producing activity in the patient and in a CRISPR-Cas9 gene-edited mouse model bearing a patient-specific SLC5A6 variant. Our results demonstrate the critical role of metabolic reprogramming in the maturation of plasma cells and nominate SLC5A6 as a causative gene for immunodeficiency that may be treated by biotin replenishment.

PMID:38036278 | DOI:10.1016/j.clim.2023.109855

Front Genet. 2023 Nov 13;14:1209988. doi: 10.3389/fgene.2023.1209988. eCollection 2023.

ABSTRACT

Background: The pathogenesis of common variable immunodeficiency disorder (CVID) is complex, especially when combined with autoimmunity. Genetic factors may be potential explanations for this complex situation, and whole genome sequencing (WGS) provide the basis for this potential. Methods: Genetic information of patients with CVID with autoimmunity, together with their first-degree relatives, was collected through WGS. The association between genetic factors and clinical phenotypes was studied using genetic analysis strategies such as sporadic and pedigree. Results: We collected 42 blood samples for WGS (16 CVID patients and 26 first-degree relatives of healthy controls). Through pedigree, sporadic screening strategies and low-frequency deleterious screening of rare diseases, we obtained 9,148 mutation sites, including 8,171 single-nucleotide variants (SNVs) and 977 Insertion-deletions (InDels). Finally, we obtained a total of 28 candidate genes (32 loci), of which the most common mutant was LRBA. The most common autoimmunity in the 16 patients was systematic lupus erythematosis. Through KEGG pathway enrichment, we identified the top ten signaling pathways, including “primary immunodeficiency”, “JAK-STAT signaling pathway”, and “T-cell receptor signaling pathway”. We used PyMOL to predict and analyse the three-dimensional protein structures of the NFKB1, RAG1, TIRAP, NCF2, and MYB genes. In addition, we constructed a PPI network by combining candidate mutants with genes associated with CVID in the OMIM database via the STRING database. Conclusion: The genetic background of CVID includes not only monogenic origins but also oligogenic effects. Our study showed that immunodeficiency and autoimmunity may overlap in genetic backgrounds. Clinical Trial Registration: identifier ChiCTR2100044035.

PMID:38028622 | PMC:PMC10679925 | DOI:10.3389/fgene.2023.1209988

Qatar Med J. 2023 Nov 19;2023(2):9. doi: 10.5339/qmj.2023.sqac.9. eCollection 2023.

ABSTRACT

INTRODUCTION: Severe combined immunodeficiency disease (SCID) is a rare primary immunodeficiency disease, usually manifest in the first six months of life with failure to thrive, oral thrush, recurrent respiratory infection, and chronic diarrhea.

CASE PRESENTATION: In three male patients, we describe an unusual presentation of SCID. They are an outcome of consanguineous marriage; all received the BCG vaccine at birth. All three cases presented with regional lymphadenopathy at three months, progressing to generalized lymphadenopathy treated with anti-tuberculous. The first and second cases were twins. The first had an uneventful history until 33 months when he developed multiple Suppurative Tuberculous lymphadenitis confirmed by biopsy. The second and the third cases were diagnosed with Disseminated Tuberculosis at 24 months as they developed fever, anemia, weight loss, tuberculous peritonitis, and lymphadenopathy confirmed by biopsy. After investigations, the first case was diagnosed as CD4, CD16 lymphopenic SCID, the second one as CD4, CD8, CD19, CD16 lymphopenic SCID with hypogammaglobulinemia and the third case as CD3, CD4, CD8 lymphopenic SCID with hypogammaglobulinemia. They received anti-Tuberculous medications, prophylactic Trimethoprim/Sulfamethoxazole, and Immunoglobulin infusion. When writing this abstract, the patients were alive and had no other bacterial, viral, or fungal infections. The twins are three years old, and the third case is 30 months old.

CONCLUSION: SCID may not exhibit the classical manifestation of recurrent infections. It may present only as a complication of the BCG vaccine, alarming to maintain high susceptibility in such patients, especially in a developing country, specifically in Sudan, where the BCG vaccine is usually given at birth.

PMID:38025336 | PMC:PMC10660256 | DOI:10.5339/qmj.2023.sqac.9

Qatar Med J. 2023 Nov 19;2023(2):3. doi: 10.5339/qmj.2023.sqac.3. eCollection 2023.

ABSTRACT

INTRODUCTION: Subcutaneous immunoglobulin (SCIG) and intravenous immunoglobulin (IVIG) are used for the treatment of primary immunodeficiency (PIDD). SCIG is as effective as IVIG in preventing infections.¹ However, SCIG has advantages over IVIG as it causes fewer systemic reactions and can be infused at home by the patient leading to improved quality of life.² Methods: We retrospectively analyzed adult patients with PIDD who received SCIG in an Adult Allergy Clinic in Qatar. Patients who received IVIG before SCIG and are naïve to IgG replacement were included. We compared Serum IgG levels, the number of antibiotic courses received, and the number of hospital admissions one year before and one year after starting SCIG. SF36 score was used to compare health-related quality of life scores before SCIG and after one year of SCIG.

RESULTS: Twenty patients were included in the study, of which 17 were on prior IVIG replacement, and three were naive to replacement. SCIG replacement resulted in the maintenance of serum IgG levels in those who received IVIG prior. SCIG resulted in a statistically significant reduction in the number of antibiotics prescribed and hospitalization in the naïve subgroup but no substantial change in the prior IVIG group. 6/20 patients developed side effects like injection site pain, swelling, and headache. No patients developed significant systemic side effects. 10/20 patients discontinued the SCIG therapy, four patients due to side effects, and others due to noncompliance and financial reasons. SF36 Score was compared for the five patients in IVIG prior group and showed no significant improvement in individual score but improvement in the overall score (p=0.003) Conclusions: In our experience, SCIG therapy effectively prevents recurrent infection in PIDD patients, and patients did not experience any significant systemic side effects. There is a substantial improvement in the quality of life. However, compliance continues to be a problem.

PMID:38025333 | PMC:PMC10660831 | DOI:10.5339/qmj.2023.sqac.3

Front Immunol. 2023 Oct 31;14:1279201. doi: 10.3389/fimmu.2023.1279201. eCollection 2023.

ABSTRACT

Primary immune regulatory disorders (PIRDs) are inborn errors of immunity caused by a loss in the regulatory mechanism of the inflammatory or immune response, leading to impaired immunological tolerance or an exuberant inflammatory response to various stimuli due to loss or gain of function mutations. Whilst PIRDs may feature susceptibility to recurrent, severe, or opportunistic infection in their phenotype, this group of syndromes has broadened the spectrum of disease caused by defects in immunity-related genes to include autoimmunity, autoinflammation, lymphoproliferation, malignancy, and allergy; increasing focus on PIRDs has thus redefined the classical ‘primary immunodeficiency’ as one aspect of an overarching group of inborn errors of immunity. The growing number of genetic defects associated with PIRDs has expanded our understanding of immune tolerance mechanisms and prompted identification of molecular targets for therapy. However, PIRDs remain difficult to recognize due to incomplete penetrance of their diverse phenotype, which may cross organ systems and present to multiple clinical specialists prior to review by an immunologist. Control of immune dysregulation with immunosuppressive therapies must be balanced against the enhanced infective risk posed by the underlying defect and accumulated end-organ damage, posing a challenge to clinicians. Whilst allogeneic hematopoietic stem cell transplantation may correct the underlying immune defect, identification of appropriate patients and timing of transplant is difficult. The relatively recent description of many PIRDs and rarity of individual genetic entities that comprise this group means data on natural history, clinical progression, and treatment are limited, and so international collaboration will be needed to better delineate phenotypes and the impact of existing and potential therapies. This review explores pathophysiology, clinical features, current therapeutic strategies for PIRDs including cellular platforms, and future directions for research.

PMID:38022498 | PMC:PMC10645063 | DOI:10.3389/fimmu.2023.1279201

Cureus. 2023 Oct 25;15(10):e47631. doi: 10.7759/cureus.47631. eCollection 2023 Oct.

ABSTRACT

Hemophagocytic lymphohistiocytosis (HLH) is an uncommon condition that can be fatal due to overwhelming macrophage activation and cytokine production. It can be primary (familial/genetic) or secondary. It is associated with infections, malignancies, and rheumatologic and immunodeficiency disorders. We report a middle-aged female patient with sickle cell anemia who presented with COVID-19 infection that triggered a vaso-occlusive crisis and resulted in HLH. She had preexisting high ferritin levels and cytopenias, making the diagnosis more challenging. A high index of suspicion and timely treatment is essential to prevent adverse outcomes.

PMID:38022077 | PMC:PMC10667952 | DOI:10.7759/cureus.47631

Clin Transl Immunology. 2023 Nov 22;12(11):e1475. doi: 10.1002/cti2.1475. eCollection 2023.

ABSTRACT

OBJECTIVES: Thymus implantation is a recently FDA-approved therapy for congenital athymia. Patients receiving thymus implantation develop a functional but incomplete T cell compartment. Our objective was to develop a mouse model to study clinical thymus implantation in congenital athymia and to optimise implantation procedures to maximise T cell education and expansion of naïve T cells.

METHODS: Using Foxn1 ^nu athymic mice as recipients, we tested MHC-matched and -mismatched donor thymi that were implanted as fresh tissue or cultured to remove donor T cells. We first implanted thymus under the kidney capsule and then optimised intramuscular implantation. Using competitive adoptive transfer assays, we investigated whether the failure of newly developed T cells to expand into a complete T cell compartment was because of intrinsic deficits or whether there were deficits in engaging MHC molecules in the periphery. Finally, we tested whether recombinant IL-7 would promote the expansion of host naïve T cells educated by the implanted thymus.

RESULTS: We determined that thymus implants in Foxn1 ^nu athymic mice mimic many aspects of clinical thymus implants in patients with congenital athymia. When we implanted cultured, MHC-mismatched donor thymus into Foxn1 ^nu athymic mice, mice developed a limited T cell compartment with notably underdeveloped naïve populations and overrepresented memory-like T cells. Newly generated T cells were predominantly educated by MHC molecules expressed by the donor thymus, thus potentially undergoing another round of selection once in the peripheral circulation. Using competitive adoptive transfer assays, we compared expansion rates of T cells educated on donor thymus versus T cells educated during typical thymopoiesis in MHC-matched and -mismatched environments. Once in the circulation, regardless of the MHC haplotypes, T cells educated on a donor thymus underwent abnormal expansion with initially more robust proliferation coupled with greater cell death, resembling IL-7 independent spontaneous expansion. Treating implanted mice with recombinant interleukin (IL-7) promoted homeostatic expansion that improved T cell development, expanded the T cell receptor repertoire, and normalised the naïve T cell compartment.

CONCLUSION: We conclude that implanting cultured thymus into the muscle of Foxn1 ^nu athymic mice is an appropriate system to study thymus implantation for congenital athymia and immunodeficiencies. T cells are educated by the donor thymus, yet naïve T cells have deficits in expansion. IL-7 greatly improves T cell development after thymus implantation and may offer a novel strategy to improve outcomes of clinical thymus implantation.

PMID:38020730 | PMC:PMC10665642 | DOI:10.1002/cti2.1475

Immun Inflamm Dis. 2023 Nov;11(11):e1084. doi: 10.1002/iid3.1084.

ABSTRACT

BACKGROUND: Kimura disease (KD) is a rare chronic inflammatory disorder involving the Th2 pathway. Although medical treatment with steroids or other immunosuppressants is available, they may cause developmental issues in the pediatric population. Surgical intervention has also been suggested; however, it is associated with high recurrence rates.

CASE PRESENTATION: A 14-year-old boy presented with left retroauricular lymph node enlargement at the age of 5 years. At the age of 7 years, he was diagnosed with nephrotic syndrome which subsided after steroid treatment for approximately 6 years. The retroauricular lymph node was surgically excised, and KD was confirmed. However, recurrent enlargement of the left retroauricular and neck lymph nodes occurred after 2 years. Persistently high IgE levels and fluctuating eosinophil counts were observed following steroid treatment. Dupilumab was prescribed because of the difficulty in tapering the steroid dosage. A loading dose of 600 mg was administered, followed by a maintenance dose of 300 mg every 2 weeks. The IgE level decreased after 3 months, and a low eosinophil count was maintained after steroid discontinuation. Follow-up computed tomography revealed a decrease in the size of the lymph nodes with no side effects such as conjunctivitis.

CONCLUSION: Traditional treatments have raised developmental concerns in the pediatric population and are associated with high recurrence rates. Dupilumab targets the Th2 pathway and provides effective results, with few adverse effects. Dupilumab may be a therapeutic option for KD and other diseases involving the Th2 pathway.

PMID:38018601 | DOI:10.1002/iid3.1084