Normal Immunoglobulin Levels Research Articles

Primary Immunodeficiency: Specific antibody deficiency with normal IgG.

Specific antibody deficiency (SAD) is a common primary immunodeficiency disorder that should be considered in older children and adults with recurrent and/or severe sinopulmonary infections. The diagnosis is characterized by inadequate antibody response to polysaccharide vaccine, specifically, pneumococcal, with normal responses to protein antigens and normal levels of serum immunoglobulins as well as immunoglobulin G (IgG) subclasses. The underlying mechanism for SAD is not completely elucidated. It is understood that young children have limited polysaccharide responsiveness, which develops with increased age. Due to this phenomenon, the consensus is that there is adequate immune maturity after age 2 years, which is the earliest for the SAD diagnosis to be established. There remains a lack of consensus on thresholds for polysaccharide nonresponse, and there are several commercial laboratories that measure a range of serotypes, with the recommendation for patients to have their diagnostic evaluation with serotype testing both before vaccination and after vaccination to be conducted by the same laboratory. Once a diagnosis has been made, the management of SAD is based on the clinical severity. Clinicians may consider prophylactic antibiotics as well as immunoglobulin replacement. These patients should be closely followed up, with the possibility of discontinuation of IgG replacement after 12 to 24 months. Children are more likely to demonstrate resolution of SAD than are adolescents and adults. Patients with SAD may also progress to a more severe immunodeficiency; therefore, continued monitoring remains a crucial principle of practice in the care of patients with SAD.

An unusual case of HHV-8 negative, idiopathic, multicentric Castleman disease following chronic lymphocytic leukaemia

Background: Castleman disease is a rare condition characterised by polytypic lymphocytes proliferation and lymphadenopathy generally with a benign course. Whereas high grade lymphoma (Richter syndrome) is a classical complication seen in chronic lymphocytic leukaemia with a poor outcome, benign conditions mimicking this entity are infrequent. Case description: We describe the case of an 81-year-old Caucasian male who developed a human herpesvirus-8 (HHV-8)–negative, idiopathic multicentric Castleman disease (iMCD) following a treated Binet C chronic lymphocytic leukaemia (CLL). The clinical and radiological pattern raised initially the suspicion of a classical Richter transformation. Blood analysis showed auto-immune haemolytic anaemia and thrombocytopenia. He had normal immunoglobulin levels. The anatomopathological analysis of a cervical adenomegaly showed hypervascularisation and a polytypic plasmocytic proliferation compatible with a plasmocytic iMCD type. Interestingly, bone marrow examination showed reticuline fibrosis but, in the absence of anasarca or generalised oedema, we were not allowed to conclude to the diagnosis of a TAFRO syndrome. We exclude all other mimicking conditions, comprising haematological malignancies, infections, and auto-immune diseases He was first treated with corticosteroids with poor results but dramatically responded to tocilizumab (anti-Il6). Conclusion: To our knowledge, this the first case described of a Castleman disease following CLL and surprisingly mimicking Richter syndrome. Clinicians should be aware of this rare misleading condition.

Clinical efficacy of prophylactic intravenous immunoglobulin for elderly DLBCL patients with hypogammaglobulinemia in the COVID-19 pandemic era.

Elderly patients diagnosed with diffuse large B-cell lymphoma (DLBCL) undergoing reduced intensity R-CHOP therapy are at a heightened risk of acquiring infections, notably coronavirus disease 2019 (COVID-19) infection. This study aimed to evaluate the efficacy of intravenous immunoglobulin (IVIG) as prophylaxis against COVID-19 in this vulnerable population. A total of 125 elderly patients with DLBCL undergoing reduced intensity R-CHOP therapy were analyzed in this prospective, multicenter study. Patients with hypogammaglobulinemia were categorized into IVIG and non-IVIG groups, while those with normal immunoglobulin levels constituted the observation group. The study evaluated COVID-19 infection rates, therapy response, and safety outcomes. Among the enrolled patients (median age: 77 years), 89 patients (71.2%) presented with hypogammaglobulinemia at diagnosis, and 56 patients enrolled in the IVIG administration group. IVIG administration remarkably reduced COVID-19 infection rates compared to non-IVIG recipients (8.9% vs. 24.6%; p =0.040). Notably, patients over 80 years old were more susceptible to COVID-19. Patients on IVIG exhibited good tolerance with manageable adverse events. Among patients with hypogammaglobulinemia who received IVIG, 40.5% of patients developed additional immunoglobulin deficiencies during chemotherapy. One or more new hypogammaglobulinemia occurred during chemotherapy in 72% of patients with hypogammaglobulinemia who did not receive IVIG, and in 61.3% of patients who did not have hypogammaglobulinemia at diagnosis. IVIG showed promise in reducing COVID-19 infections among elderly patients with DLBCL receiving reduced intensity R-CHOP therapy. This highlights IVIG's potential as a prophylactic measure, necessitating further investigation to optimize dosing, administration schedules, and potential interactions with vaccination strategies.

An Unusual Case of HHV-8 Negative, Idiopathic, Multicentric Castleman Disease Following Chronic Lymphocytic Leukaemia.

Castleman disease is a rare condition characterised by polytypic lymphocytes proliferation and lymphadenopathy generally with a benign course. Whereas high grade lymphoma (Richter syndrome) is a classical complication seen in chronic lymphocytic leukaemia with a poor outcome, benign conditions mimicking this entity are infrequent. We describe the case of an 81-year-old Caucasian male who developed a human herpesvirus-8 (HHV-8)-negative, idiopathic multicentric Castleman disease (iMCD) following a treated Binet C chronic lymphocytic leukaemia (CLL). The clinical and radiological pattern raised initially the suspicion of a classical Richter transformation. Blood analysis showed auto-immune haemolytic anaemia and thrombocytopenia. He had normal immunoglobulin levels. The anatomopathological analysis of a cervical adenomegaly showed hypervascularisation and a polytypic plasmocytic proliferation compatible with a plasmocytic iMCD type. Interestingly, bone marrow examination showed reticuline fibrosis but, in the absence of anasarca or generalised oedema, we were not allowed to conclude to the diagnosis of a TAFRO syndrome. We excluded all other mimicking conditions, comprising haematological malignancies, infections, and auto-immune diseases He was first treated with corticosteroids with poor results but dramatically responded to tocilizumab (anti-Il6). To our knowledge, this the first case described of a Castleman disease following CLL and surprisingly mimicking Richter syndrome. Clinicians should be aware of this rare misleading condition. Castleman disease can mimic a Richter transformation in a CLL patient.

Combined deficient response to polysaccharide-based and protein-based vaccines predicts a severe clinical phenotype.

Antibody response on polysaccharide- and protein-based vaccines is useful to test Bcell functionality. As only few studies have explored the value of studying immune response to both vaccines, we evaluated the clinical value of anti-polysaccharide and anti-protein Luminex-based multiplex assays in context of primary immunodeficiency (PID) diagnosis. A 10-plex Luminex-based assay detecting antibodies to ten pneumococcal polysaccharide (PnPS) serotypes [present in unconjugated Pneumovax, not in 13-valent pneumococcal conjugated vaccine (PCV)] and a 5-plex assay detecting antibodies to five protein antigens (present in DTap/Tdap) were clinically validated in healthy individuals (n=99) and in retrospective (n=399) and prospective (n=108) patient cohorts. Clinical features of individuals with impaired response to PnPS and/or proteins were compared to those with normal response. Antigen-specific antibody thresholds were determined in healthy individuals. Individuals with impaired anti-PnPS responses and deficient immunoglobulin levels suffered more from autoimmune diseases and had lower Bcell levels compared to individuals with impaired anti-PnPS response with normal immunoglobulin levels. Individuals with combined impaired response to PnPS and proteins showed more severe clinical manifestations compared to individuals with isolated impaired response to PnPS or proteins. Eight of the 11 individuals with severely impaired responses to both PnPS and proteins had common variable immunodeficiency. Evaluation of the anti-PnPS response to four serotypes not contained in 20-valent PCV was comparable to evaluation to ten serotypes not contained in 13-valent PCV. Multiplexed assessment of anti-PnPS and anti-protein responses combined with immunoglobulin quantification provides useful clinical information to support PID diagnosis.

#5076 MONOCLONAL GAMMOPATHY IN C3 GLOMERULOPATHY: DOES THE BUCKET STOP THERE?

Abstract Background and Aims C3 glomerulopathy (C3G) is a rare diagnosis, characterized by dysregulation of the alternative pathway of complement, classically presenting in children and young adults. Recently, it has been reported the association between the production of a monoclonal protein and the development of C3G, affecting a larger age span. Method We report the case of a 53-year-old male patient, that attended the emergency department due to persistent holocranial headache. He was an IV drug abuser with a history of treated Hepatitis C infection and free lambda light chain monoclonal protein, being studied by the Haematology Department. On admission, he was hypertensive (187/98 mmHg), and labs showed an acute on chronic kidney disease (serum creatinine 2.35 mg/dL from a basal of 1.5 mg/dL) with an active urinary sediment (38 erythrocytes/field, with dysmorphia), a urinary protein/creatinine ratio of 626 mg/g, and C3 consumption (0.52 g/L). The patient was admitted, and a kidney biopsy was performed. Results Further lab results confirmed a serum IgG Lambda monoclonal protein. Autoantibodies screening (ANCAs, ANAs, Anti-GBM), ASLO and Rheumatoid Factor were negative. Cryoglobulinemia was detected, and the cryoprecipitate's immunofixation revealed monoclonal proteins IgG Lambda and IgM Kappa. HCV viral load was negative. Bone marrow biopsy revealed a small population (< 3%) of plasma cells with Lambda light chain restriction. Kidney biopsy's light microscopy showed increased mesangial matrix and cells, endocapillary hypercellularity, and some glomeruli with lobulated appearance. Five out of 15 glomeruli presented fibrocellular crescents. Immunofluorescence showed C3 dominant staining on capillary walls and in the mesangium, with absent IgG and light chain deposits. A presumptive diagnosis of C3 glomerulopathy was made and the patient was empirically started on corticosteroids (3 pulses of intravenous methylprednisolone, followed by oral prednisolone 1mg/Kg/day), which was followed by paraprotein-directed chemotherapy with bortezomib, cyclophosphamide and dexamethasone (VCD). The patient is currently on the third VCD cycle, presenting both renal and haematological responses: recovery of serum creatinine to basal levels (1.54 mg/dL), resolution of haematuria and proteinuria, normalisation of C3 levels. Serum immunofixation is currently negative for monoclonal protein, with normal serum immunoglobulin levels. Electron microscopy revealed electron-dense deposits in the mesangium, and mesangium-capillary transition, supporting the diagnosis of C3 glomerulonephritis. Genetic testing of complement-related genes revealed a rare missense variation of unknown significance (c.4855A>C) on the C3 gene, that has been previously reported in association with C3 glomerulopathy and atypical Haemolytic-Uremic syndrome. Conclusion This case represents a monoclonal gammopathy associated-C3 glomerulonephritis with a favourable response to paraprotein-directed chemotherapy. Although the association between monoclonal gammopathy and C3G rests on epidemiologic findings, experimental evidence suggests that several monoclonal proteins have complement dysregulation features, which may enhance alternate complement pathway activation. Our patient's response is in line with observational data that have shown improved renal outcomes in patients who achieve a haematological response following clone-directed chemotherapy, which further supports the role of monoclonal gammopathy in C3G pathogenesis [1]. Interestingly, the genetic variation identified in our patient might have provided a favourable genetic background for the development of C3G, which is thought to rely upon a complex interaction of triggering events, such as a monoclonal gammopathy, and underlying complement abnormalities, such as genetic variants in complement genes.

Mycobacterium avium Complex Infections: Detailed Phenotypic and Functional Immunological Work-Up Is Required despite Genetic Analyses

Introduction: Cervical scrofulous lymphadenitis due to Mycobacterium avium complex (MAC) in immunocompetent adults is a rare disease. The presence of MAC infections demands meticulous clinical evaluation of patients along with detailed phenotypic and functional evaluation of their immune system including next-generation sequencing (NGS) analyses of target genes. Methods: Exact clinical histories of the index patients both suffering from retromandibular/cervical scrofulous lymphadenitis were obtained along with phenotypic and functional immunological evaluations of leukocyte populations followed by targeted NGS-based sequencing of candidate genes. Results: Immunological investigations showed normal serum immunoglobulin and complement levels, but lymphopenia, which was caused by significantly reduced CD3+CD4+CD45RO+ memory T-cell and CD19+ B-cell numbers. Despite normal T-cell proliferation to a number of accessory cell-dependent and -independent stimuli, the PBMC of both patients elaborated clearly reduced levels of a number of cytokines, including IFN-γ, IL-10, IL-12p70, IL-1α, IL-1β, and TNF-α upon TCR-dependent T-cell stimulation with CD3-coated beads but also superantigens. The IFN-γ production deficiency was confirmed for CD3+CD4+ helper and CD4+CD8+ cytotoxic T cells on the single-cell level by multiparametric flow cytometry irrespective of whether PMA/ionomycin-stimulated whole blood cells or gradient-purified PBMC was analyzed. In the female patient L1, targeted NGS-based sequencing revealed a homozygous c.110T>C mutation in the interferon-γ receptor type 1 (IFNGR1) leading to significantly reduced receptor expression on both CD14+ monocytes and CD3+ T cells. Patient S2 presented with normal IFNGR1 expression on CD14+ monocytes but significantly reduced IFNGR1 expression on CD3+ T cells, despite the absence of detectable homozygous mutations in the IFNGR1 itself or disease-related target genes. Exogenous addition of increasing doses of IFN-γ resulted in proper upregulation of high-affinity FcγRI (CD64) on monocytes from patient S2, whereas monocytes from patient L1 showed only partial induction of CD64 expression after incubation with high doses of IFN-γ. Conclusion: A detailed phenotypic and functional immunological examination is urgently required to determine the cause of a clinically relevant immunodeficiency, despite detailed genetic analyses.

A case of Familial Mediterranean Fever presented with recurrent infection.

The periodic fever syndrome Familial Mediterranean Fever (FMF) is caused by mutations in MEFV, which promote inflammation and present with uncontrolled systemic and organ-specific inflammation that can resemble infectious conditions. It is diagnosed based on clinical criteria, including frequent symptoms such as abdominal and thoracic pain, family history, and response to treatment with colchicine, which is confirmed by genetic assessment. Herein, we present a case of FMF with a relatively uncommon presentation. A 22-month-old female was referred to the allergy and clinical immunology clinic with eczematoid skin rashes. She was admitted to the hospital several times since the 2nd day of life with different complaints like fever, seizure, and restlessness, and treated with the diagnosis of septicemia. Endoscopy and colonoscopy were done at the age of 6 months due to poor weight gain and bloody diarrhea, which revealed active crypt-destructive colitis with foci of erosion in favor of infectious or allergic colitis. The colon biopsy was negative for Cytomegalovirus (CMV). Regarding family history, she was the second child of the first cousins parents and had a healthy 12-year-old sister. There was a history of death for unknown reasons of her cousin, whose parents were related. The immunologic evaluation was done, which showed a relatively normal immunoglobulin level, antibody response, flow cytometry, and lymphocyte transformation test. Nonetheless, a genetic study was done, which showed a homozygote mutation in exon 10 of the MEFV gene in the patient and a heterozygote mutation in both her parents. The periodic fever syndrome Familial Mediterranean Fever (FMF) is caused by mutations in MEFV, which promote inflammation and present with uncontrolled systemic and organ-specific inflammation that can resemble infectious conditions. The patient was diagnosed with FMF, and treatment was started using colchicine, which successfully controlled the patient's symptoms and prevented the recurrence of fever and other inflammatory manifestations.

Immunodeficiency in a female patient with Incontinentia Pigmenti

Incontinentia pigmenti (IP) is a rare X-linked dominant neuroectodermal disorder characterized by ocular, dermatologic, and neurological abnormalities. It is caused by heterozygous mutations in IKBKG (NEMO), which encodes a regulatory factor involved in NF-kB activation. Random and skewed X-inactivation allows for female survival and determines extent of disease. Although immune function is typically normal in IP patients, hypomorphic IKBKG mutations are known to cause immunodeficiency, as occurs in X-linked NEMO deficiency. A female newborn presented with bullous vesicles, peeling skin, alopecia, hearing loss, and tonic-clonic seizures with MRI demonstrating evidence of in utero stroke. She developed intermittent fevers and cellulitis and was diagnosed with IP based on clinical findings. Following discharge, she was readmitted at 1 month of age due to bronchiolitis complicated by pulmonary abscess. Labs demonstrated hyperleukocytosis with hypereosinophilia, normal T, B, and NK lymphocyte enumeration, abnormal lymphocyte proliferation to phytohemagglutinin (PHA) and anti-CD3, and abnormal toll-like receptor (TLR) function. Genetic analysis revealed a heterozygous deletion of exons 4–10 in IKBKG. Labs at 1 year follow up showed normal lymphocyte (T, B, and NK) enumeration and mitogen responses, normal immunoglobulin levels, and normal responses to pneumococcal and tetanus vaccines. While about 70% of IP patients harbor a deletion of exons 4–10 in IKBKG. unlike other hypomorphic NEMO mutations, this mutation is not typically associated with altered immune function. This case highlights that immunodeficiency may be an early clinical manifestation in female patients with IP.

Atypical Presentations of Hypomorphic X-Linked SCID

RationaleIL2RG mutations are associated with X-linked Severe Combined Immunodeficiency (X SCID). There is increasing awareness of Hypomorphic SCID associated with IL2RG variants; we present 3 novel mutations of this gene with variable presentations. MethodsChart review was performed for patients with hypomorphic SCID due to pathogenic IL2RG variants. Plasmablast differentiation was performed from peripheral blood mononuclear cells using CD40L and IL-21 stimulation for 6 days followed by staining for plasmablast markers (CD19+/CD27+/CD38+) and surface immunoglobulins. ResultsPatient 1 is a 7-year-old Honduran boy with history of recurrent sinopulmonary infections including recent CMV pneumonitis, bronchiectasis, chronic lung disease, food allergies, unilateral retinal detachment, and hydrocephalus s/p VP shunt. Immunologic testing showed elevated lymphocyte numbers with decreased memory B cells, normal immunoglobulins, absent vaccine responses, and poor proliferation to mitogens. Whole genome testing showed two mosaic mutations in IL2RG: c. 568C>T (20%), c. 589T>C (87%). He is on prophylaxis with azithromycin and trimethoprim/sulfamethoxazole, immunoglobulin, and awaiting definitive treatment. Patient 2 is a 10-year-old with recurrent sinopulmonary disease with bronchiectasis. He had normal TRECs, normal lymphocyte numbers with normal mitogen proliferation to PHA, normal immunoglobulin levels, but absent vaccine responses, and abnormal plasmablast differentiation (0.12% CD27+/CD38+ at day 6 post in vitro activation) and profoundly decreased expression of surface IgG and IgA in vitro. Genetic testing showed a hemizygous IL2RG c.32T>C mutation, as well as CFTR mutations (c.1972dup and c.1977_1985del, in cis). He is maintained on immunoglobulin replacement. Patient 3 is a 40-year-old who had recurrent infections beginning in childhood, and extranodal B-cell lymphoma at age 26 years. He had pan-lymphopenia, and genetic testing showed IL2RG c.982C>T, p.R328X. He underwent successful bone marrow transplantation from a matched sibling at age 36. ConclusionsHypomorphic X-SCID due to novel or mosaic variants in IL2RG can present with variable symptoms including malignancy and variable lymphocyte phenotype including normal T, B, and NK cell counts, and should be considered in males with opportunistic or persistent infections. [Display omitted]

A rare immunological disease, caspase 8 deficiency: case report and literature review

BackgroundCaspase-8 is a molecule in the FAS pathway that initiates apoptosis. One of the rarest autoimmune lymphoproliferative syndromes is caspase-8 deficiency. Immunodeficiency, splenomegaly, and lymphadenopathy are the common symptoms of this condition.Case PresentationA two-year-old boy entered this study with a fever of unknown origin (FUO) and dysentery. Moreover, he suffered from failure to thrive and was allergic to the cow's milk protein. His fever and dysentery did not respond to antibiotic therapy. The colonoscopy revealed diffuse ulcerations regions in the sigmoid along with skipped areas, mimicking Crohn's disease aphthous lesions. He represented very early-onset inflammatory bowel disease (IBD) and was diagnosed with the caspase-8 deficiency.ConclusionThere can be diarrhea or dysentery as the first or main symptoms of inborn errors of immunity (IEIs). The cause of diarrhea and dysentery in this case was early-onset IBD. One of the symptoms of IEIs such as caspase-8 deficiency is early-onset of IBD. Patients with early-onset had normal T cell count and low or normal immunoglobulin levels with insufficient immune response.

Reduced G protein signaling despite impaired internalization and β-arrestin recruitment in patients carrying a CXCR4Leu317fsX3 mutation causing WHIM syndrome.

WHIM syndrome is an inherited immune disorder caused by an autosomal dominant heterozygous mutation in CXCR4. The disease is characterized by neutropenia/leukopenia (secondary to retention of mature neutrophils in bone marrow), recurrent bacterial infections, treatment-refractory warts, and hypogammaglobulinemia. All mutations reported in WHIM patients lead to the truncations in the C-terminal domain of CXCR4, R334X being the most frequent. This defect prevents receptor internalization and enhances both calcium mobilization and ERK phosphorylation, resulting in increased chemotaxis in response to the unique ligand CXCL12. Here, we describe 3 patients presenting neutropenia and myelokathexis, but normal lymphocyte count and immunoglobulin levels, carrying what we believe to be a novel Leu317fsX3 mutation in CXCR4, leading to a complete truncation of its intracellular tail. The analysis of the L317fsX3 mutation in cells derived from patients and in vitro cellular models reveals unique signaling features in comparison with R334X mutation. The L317fsX3 mutation impairs CXCR4 downregulation and β-arrestin recruitment in response to CXCL12 and reduces other signaling events - including ERK1/2 phosphorylation, calcium mobilization, and chemotaxis - all processes that are typically enhanced in cells carrying the R334X mutation. Our findings suggest that, overall, the L317fsX3 mutation may be causative of a form of WHIM syndrome not associated with an augmented CXCR4 response to CXCL12.

Skin Manifestations in Patients with Selective Immunoglobulin E Deficiency.

Selective immunoglobulin E deficiency (SIgED) is still an unrecognised primary immunodeficiency despite several observations supporting its existence. This study aimed to describe the skin manifestations associated with SIgED. We retrospectively assessed medical records of patients with SIgED, the diagnosis being based on serum IgE levels ≤2 Uk/L associated with normal serum levels of immunoglobulins G, M, and A. A total of 25 patients (24 female) with SIgED were included in the study. Eleven patients (44%) presented chronic spontaneous urticaria (CSU), five (20%) angioedema always associated with CSU, five erythema (20%), and six eczema (24%). Other, less frequent manifestations were lichen planus, anaphylactoid purpura, thrombocytopenic purpura, bullous pemphigoid, bullous pyoderma gangrenosum, and atypical skin lymphoproliferative infiltrate associated with reactive lymphadenopathy, chronic cholestasis, arthritis, and fibrosing mediastinitis. Fifteen patients (60%) had different types of associated autoimmune diseases, Hashimoto's thyroiditis being the most frequent (n = 5, 20%), followed by arthritis (n = 4, 16%), autoimmune hepatitis, neutropenia, vitiligo, and Sjögren's syndrome (n = 2, 8% each). Five malignancies were diagnosed in four patients (16%). An ultralow IgE serum level may be the only biomarker that reveals the presence of a dysregulated immune system in patients with a broad spectrum of skin manifestations.

How to Treat Isolated Leptomeningeal Relapse of Multiple Myeloma 11 Years after Autologous Stem Cell Transplantation (ASCT)

Post transplant relapse of Multiple Myeloma (MM) in the central nervous system (CNS) is rare and it is almost always associated with systematic relapse and in most instances, shortly after initial treatment. We did not encounter reports of relapse isolated to the CNS ten years post-transplant. In October 2009, a 49-year-old male presented with an IgG lambda MM, ISS II. He was treated with Bortezomib/Dexamethasone, autologous PBSCT, followed by two years maintenance with Lenalidomide, attaining stringent CR, confirmed by PET/CT. He discontinued follow up and returned after 11y/8m progression free survival, in June 2021 with paraplegia due to cauda equina syndrome. NMR consistent with leptomeningeal infiltration, single focal intramedullary lesion at L1 level without bone affectation. No MM defining criteria (CRAB). Normal levels of serum Immunoglobulins (IGs), serum and urine immunofixation, and serum free light chains. Flow cytometry negative in bone marrow. Spinal tap was unsuccessful and through an Ommaya reservoir, that was placed after NMR showed evidence of cranial leptomeningeal involvement, CSF showed infiltration by countless malignant plasma cells. Patient received immediate conformational radiotherapy and biweekly IT methotrexate and hydrocortisone. A month later his course was complicated by left leg proximal deep vein thrombosis and pulmonary embolism which was treated with Apixaban. Given the rarity of this type of relapse, we questioned the appropriateness of the treatment and searched the literature with respect to the accessibility of the CNS by the different novel drugs used to treat MM in order to determine the most effective strategy. In addition to corticosteroids, there is clinical evidence that thalidomide crosses the blood-brain barrier (BBB), in murine models pomalidomide also has good penetration into the CNS. Both have a penetration of 30 to 40% into the CSF. Among proteasome inhibitors, only marizomib has been observed to cross the BBB in a murine model, while bortezomib does not. With respect to anti CD38 monoclonal antibodies, mass spectrometry at 12, 15, and 19 days after daratumumab infusion showed antibody levels in CSF 71 times less than in serum on the three sample days. It is not known if weekly doses of daratumumab could attain therapeutic levels in CSF. We found only 14 cases of isolated CNS relapse in patients with MM treated with ASCT with a median interval between transplant and relapse of 3 months (0.5-96m), with only one reported relapse 7.5 years after autologous transplant and the median overall survival was only 3 months. Two cases died in less than a month and only one case survived for a year after the CNS relapse.To date, our patient has received 12 cycles of Pomalidomide/dexamethasone with progressive improvement, now he is able to carry on his life unassisted and there is no evidence of MM relapse anywhere. The rarity of this case scenario highlights the lack of knowledge regarding the best approach to CNS MM relapse. There is no evidence of the effectiveness of methotrexate and Ara C, in MM, and no novel drug can be instilled into the CSF. We conclude that the systemic use of pomalidomide and dexamethasone should be the best approach of MM isolated CNS relapse. Further investigations will clarify if other novel drugs are active in this context.

ERYTHRODERMA AND EOSINOPHILIA WITH MULTI-SYSTEM INVOLVEMENT, A CASE OF VRESS

<h3>Introduction</h3> Resembling Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), Virus Reactivation with Eosinophilia and Systemic Symptoms (VRESS) occurs triggered by members of Herpesviridae family viruses. <h3>Case Description</h3> A 12-year-old male was hospitalized with a 5-day history of fever, pruritic erythematous rash on the trunk and extremities, and facial edema. The patient was exposed to a cousin diagnosed with Multisystem Inflammatory Syndrome in Children (MIS-C) 10 days prior. No history of traveling, unusual food intake, URI, drug ingestion during the prior 3 months. Patient was treated with clindamycin x 10 days for possible Staphylococcal Scalded Skin Syndrome. Patient was noted to have eosinophilia of >2000 that persisted through the hospital course and thereafter, transaminitis with direct bilirubinemia, transient microscopic hematuria, elevated CRP and C3, normal EKG and chest radiograph, normal T/B/NKC counts, normal levels of immunoglobulins and elevated IgE (2163>1579IU/mL). IgG and IgM were negative for: CMV, adenovirus, strongyloidces, HAV, HBV, and HIV. IgG positive to: EBV, HHV-6, mycoplasma, HHV-6, HSV1, and parvovirus. Negative cultures for MRSA and group A Streptococcus. Negative PCRs for COVID -19. At 8 week follow up, skin erythema evolved into desquamation in the fingers and eosinophilia persisted. <h3>Discussion</h3> VRESS should be on the differential for patients presenting with a DRESS-like symptoms in the absence of drug exposures. VRESS is often triggered by members of the Herpesviridae family of viruses including EBV and HHV-6, to both of which this patient was exposed to in the past. While diagnosis is one of exclusion, early identification can guide appropriate management.

RECURRENT APHTHOUS STOMATITIS AND ORAL CANDIDIASIS DUE TO STAT1 MUTATION

<h3>Introduction</h3> Chronic mucocutaneous candidiasis (CMC) often presents with chronic <i>Candida</i> infections of the skin, nails or mucous membranes in the absence of invasive fungal infections. Various genetic defects are associated with CMC. Here, we describe a case of recurrent aphthous stomatitis and chronic oral candidiasis due to gain-of-function (GOF) mutation in STAT1. <h3>Case Description</h3> A 21-year-old male presented to the Allergy and Immunology clinic with long-standing history of recurrent aphthous ulcers and oral candidiasis. He had previously undergone evaluation as a child with normal immunoglobulin levels, normal antibody response to vaccines and normal delayed-type hypersensitivity skin test to <i>Candida</i> antigen, but low absolute NK cells. Targeted genetic testing was negative for APECED and IPEX. He continued to experience frequent aphthous ulcers and oral thrush that can be debilitating at times, with one episode resulting in hospital admission due to severe mucosal pain and PO intolerance. Repeat immunology evaluation was similar to prior. He had low absolute NK cells, and NK cell function study using chromium release assay was notably decreased. A comprehensive primary immunodeficiency next generation sequencing panel identified a pathogenic heterozygous c.800C>T (p.A267V) mutation in STAT1. <h3>Discussion</h3> While fungal infection of the oral mucosa is a main clinical feature of CMC, aphthous stomatitis can be found frequently in patients with STAT1 GOF mutations as well. These patients also frequently have decreased NK cells and NK cell function. It is important to be aware of these additional phenotypes in the evaluation of a patient with CMC.

Subcutaneous Nodules in a 28-week-old Girl.

Subcutaneous Nodules in a 28-week-old Girl.

Exome sequencing contributes to identify comorbidities in a rare case of infant ARDS induced by the CD40LG mutation

BackgroundAcute respiratory distress syndrome (ARDS) causes significant mortality in young children with certain diseases. Early diagnosis and treatment can reduce infant mortality. Here, we report a rare case of exome sequencing in the early diagnosis of immunodeficiency in an infant.Case presentationA four-month-old full-term male infant presented with severe shortness of breath, hypoxemia, and unexplained parenchymal lung lesions. A series of examinations were performed to search for potential culprit viruses but negative results were obtained with the only exception being the rhinovirus that tested positive. The child’s family history revealed he had a brother who died of severe infection at the age of two years. We performed an exome sequencing analysis and a mutation analysis of CD40LG to obtain genetic data on the patient. Besides, we used flow cytometry to measure the CD40LG expression levels of activated T cells. A retrospective review of all the CD40LG mutant-induced X-linked hyper IgM syndromes (XHIGM) had been conducted to assess the differences between clinical and genetic molecular features. Finally, a regular intravenous immunoglobulin (IVIG) regimen led to steady breathing, the correction of hypoxemia, and a progressive improvement of lung CT scans. During follow-up, the patient received an IVIG regimen and his CT images improved. Moreover, his parents took advantage of pre-implantation genetic testing with in vitro fertilization to have a healthy twin offspring who did not carry such a mutation according to the early exome sequencing for the proband. Compared with other CD40LG mutant cases in our center, this proband displayed a normal plasma immunoglobulin level and he should be the youngest infant to have a molecular diagnosis of XHIGM.ConclusionUsually, XHIGM would not be suspected with a normal plasma immunoglobulin concentration. However, as we could not identify a potential comorbidity or risk factor, exome sequencing helps target this patient's real facts. Thus, this case report calls for exome sequencing to be performed in the case of unexplained infections when immunodeficiency is suspected after general immunological tests, especially for cases with a contributive family history among infants as the maternal transfused immunoglobulin might mask immune deficiency.

Comparison of Serum Immunoglobulin Levels and Lymphocyte Counts in Children with Lymphadenitis Following BCG Vaccination

Background: Lymphadenitis is the most common complication following BCG vaccination observed in 0.1% to 1% of children. Objectives: The presence of immunodeficiency can increase the probability of lymphadenitis or contribute to its exacerbation, so the early detection of immunodeficiency in those developing lymphadenitis can help prevent its many catastrophic complications. Methods: This study was performed on patients referred to Taleghani Hospital of Gorgan city in 1396. Forty children with lymphadenitis and 40 healthy children entered the study. Serum samples were taken to measure white blood cell counts and the antibodies, including IgE, IgG, IgM, and IgA. Purified protein derivative (PPD) test was done in both groups. Results: In this study, there were 40 patients with lymphadenitis, of whom 24 were boys (60%), and 16 were girls (40%), and in the control group were 22 boys (55%) and 18 girls (45%). There was no statistically significant difference between the two groups. Lymphadenitis was ipsilateral to the vaccine injection site in all 40 cases, and it was in the anterior axillary region in 82%. Abscess at the lymphadenitis site occurred in 25% of cases. The mean size of induration following PPD in the lymphadenitis group was larger than the control group (5.86 mm and 3.04 mm, respectively) (P = 0.004). There were five patients (12.5%) under one year of age with lymphopenia (lymphocyte count 3,000 &gt;), but no lymphopenia was observed in the control group. The mean average IgA and IgM levels were different between the case and control groups (P = 0.001), (P = 0.016), respectively. There was no statistical difference in IgG and IgE levels between both groups (P = 0.92 and P = 0.762, respectively). Conclusions: This study shows that the size of indurations following PPD injection is higher in those with post-vaccination lymphadenitis. Although the probability of a primary immunodeficiency disorder in the cases of our study was low considering the normal immunoglobulin levels and CBC report, further studies with a larger sample size and more specific investigations, such as flow cytometry and specific antibody response, are needed.

Exuberant Scleral Calcification from Secondary Hyperparathyroidism

A 38-year-old man with chronic end-stage renal disease and secondary hyperparathyroidism presented with bilateral ocular inflammation. Visual acuity was 20/40 in the right eye and 20/60 in the left eye with normal intraocular pressure and full extraocular motility in both eyes. Examination was notable for keratoconjunctivitis and proptosis in both eyes. Testing revealed normal thyroid function and stimulating immunoglobulin levels, but elevated phosphate (12.4 mg/ml). Computed tomography was unremarkable for orbital inflammation yet demonstrated diffuse scleral calcification (Fig A-B) confirmed on ultrasonography (Fig C).