{
  "schemaVersion": 2,
  "eyebrow": "Allergy and Immunology",
  "title": "Selective IgA Deficiency",
  "summary": "Confirm persistent, isolated severe IgA reduction after age 4, then distinguish uncomplicated disease from impaired antibody function, evolving CVID, secondary causes, and associated infection, autoimmune, allergic, or transfusion-risk phenotypes.",
  "seoDescription": "Physician guide to diagnosing selective IgA deficiency, evaluating recurrent infections and comorbidity, and managing transfusion and immunoglobulin risks.",
  "clinicalQuestion": "How should physicians confirm, phenotype, monitor, and manage selective IgA deficiency?",
  "specialty": "Allergy and Immunology",
  "audience": "U.S. physicians and medical trainees",
  "tags": [
    "selective IgA deficiency",
    "SIgAD",
    "recurrent sinopulmonary infections",
    "specific antibody deficiency",
    "CVID",
    "celiac disease",
    "anti-IgA antibodies",
    "transfusion reaction"
  ],
  "keyTakeaways": [
    "Diagnose SIgAD only in patients older than 4 years with serum IgA <7 mg/dL, normal IgG and IgM, normal vaccine responses, and exclusion of secondary hypogammaglobulinemia and T-cell defects. [9][18]",
    "Recurrent bacterial sinopulmonary infection should trigger assessment for IgG subclass deficiency and functional protein and polysaccharide antibody responses, because these coexisting defects identify a more consequential phenotype. [1][15][19]",
    "Use IgG-based celiac serology when IgA is deficient; IgA-tTG alone can miss celiac disease. [11][19]",
    "Do not use routine IVIG for isolated SIgAD; consider immunoglobulin replacement only in carefully selected severe phenotypes with a justified additional antibody defect, using a product with minimal IgA. [9][12]",
    "Document IgA deficiency before transfusion or immunoglobulin exposure, especially after a prior reaction; rare anti-IgA antibodies can mediate anaphylaxis with IgA-containing blood products or immunoglobulin. [4][12][13]"
  ],
  "sections": [
    {
      "id": "confirm-the-diagnosis",
      "eyebrow": "Diagnostic threshold",
      "heading": "Confirm isolated IgA deficiency before assigning SIgAD",
      "intro": "A low IgA value is not sufficient to establish a primary selective antibody deficiency.",
      "paragraphs": [
        "Classify SIgAD when serum IgA is <7 mg/dL in a patient older than 4 years, with normal serum IgG and IgM, normal vaccine responses, and exclusion of secondary hypogammaglobulinemia and T-cell defects. Do not apply this definitive label to younger children, in whom low IgA can be developmentally transient. [9][16][18]",
        "Repeat quantitative serum immunoglobulins when the initial result is unexpected or obtained during an acute clinical evaluation, and interpret pediatric concentrations against age-specific laboratory reference ranges. Quantify IgG and IgM concurrently: low IgG or low IgM shifts the working diagnosis away from isolated SIgAD and toward a broader humoral immunodeficiency. [18][23]",
        "Review medications and acquired conditions before diagnosing a primary disorder. Antiepileptic medications, microbiome disruption associated with antibiotics, infections, and malignancy have been associated with secondary IgA deficiency. [4][15]"
      ],
      "bullets": [
        "Obtain a CBC with differential, quantitative IgG/IgA/IgM, IgG subclasses, lymphocyte subsets, and antigen-specific responses to protein and polysaccharide antigens when IgA deficiency is clinically suspected. [15]",
        "Treat a low IgA result with abnormal IgG, impaired vaccine response, or lymphocyte abnormalities as an expanded immunodeficiency workup rather than isolated SIgAD. CVID requires low IgG with marked IgA reduction, exclusion of secondary causes and severe T-cell deficiency, plus severely altered vaccine response or reduced memory B cells. [18]"
      ],
      "subsections": [],
      "table": {
        "caption": "Laboratory patterns that determine whether low IgA represents SIgAD or another immune phenotype. [9][15][18]",
        "columns": [
          "Pattern",
          "Key findings",
          "Clinical next step"
        ],
        "rows": [
          [
            "SIgAD",
            "Age >4 years; IgA <7 mg/dL; normal IgG and IgM; normal vaccine responses; secondary causes and T-cell defects excluded. [9][18]",
            "Phenotype infection burden, allergy, autoimmunity, gastrointestinal disease, and transfusion history. [15][18]"
          ],
          [
            "Low IgA in a child younger than 4 years",
            "Does not meet age criterion for SIgAD. [9][18]",
            "Use age-adjusted interpretation and reassess immunoglobulins over time if clinical infections or immune features persist. [6][23]"
          ],
          [
            "Low IgA plus impaired polysaccharide or protein antibody responses",
            "Functional antibody defect on specific antibody testing. [15]",
            "Assess infection severity and consider immunology-directed prevention or, rarely, immunoglobulin replacement when clinically justified. [9][15]"
          ],
          [
            "Low IgA plus low IgG",
            "Pattern is inconsistent with isolated SIgAD; CVID criteria include low IgG with marked IgA reduction and impaired vaccine response or low memory B cells. [18]",
            "Evaluate for CVID and secondary hypogammaglobulinemia; refer to clinical immunology. [18]"
          ],
          [
            "Low IgA after medication, infection, or malignancy",
            "Potential secondary IgA deficiency. [4]",
            "Identify and address the associated cause before diagnosing a primary immunodeficiency. [4][15]"
          ]
        ]
      }
    },
    {
      "id": "phenotype-the-patient",
      "eyebrow": "Clinical branching",
      "heading": "Use phenotype to direct the workup",
      "intro": "Most affected individuals are asymptomatic; testing and surveillance should follow the presenting clinical branch.",
      "paragraphs": [
        "Incidentally identified, asymptomatic patients usually need confirmation of the immunoglobulin pattern and documentation rather than treatment. Approximately 85% to 90% of IgA-deficient individuals are asymptomatic, whereas symptomatic patients most often have recurrent respiratory or gastrointestinal infections, allergic disease, or autoimmunity. [15][16]",
        "For recurrent otitis, sinusitis, bronchitis, or pneumonia, obtain microbiologic data during clinically significant episodes when feasible and assess functional antibody responses to protein and polysaccharide antigens. Recurrent pulmonary infections are commonly associated with encapsulated bacteria, particularly Streptococcus pneumoniae and Haemophilus influenzae; risk is greater when IgG2 or IgG3 subclass deficiency coexists. [15][19]",
        "For chronic or recurrent diarrhea, malabsorption, or unexplained weight loss, test for Giardia lamblia and evaluate for celiac disease. SIgAD has a predilection for Giardia infection, and total IgA deficiency makes IgA-based celiac testing unreliable. [4][11][19]",
        "For severe allergic rhinitis, asthma, eczema, urticaria, conjunctivitis, food allergy, or recurrent allergic symptoms, evaluate and treat the allergic disorder on its own merits while recognizing the association with SIgAD. For autoimmune features, use organ-directed testing based on presentation because celiac disease, thyroid disease, type 1 diabetes, systemic lupus erythematosus, autoimmune cytopenias, and inflammatory arthritis are associated conditions. [18][19]"
      ],
      "bullets": [
        "Order total IgA with IgA-tTG as first-line celiac testing only when IgA is adequate; if IgA is deficient, use IgG EMA, IgG deamidated gliadin peptide, or IgG-tTG testing. [11]",
        "Obtain IgG subclasses and specific antiprotein and antipolysaccharide antibody responses when infection frequency, severity, or pathogen pattern suggests clinically meaningful humoral dysfunction. [1][15]",
        "Ask specifically about prior plasma, platelet, red-cell, or immunoglobulin reactions; anaphylaxis after a blood product is an indication for immunologic evaluation for IgA deficiency. [15]"
      ],
      "subsections": [
        {
          "heading": "When to escalate to immunology",
          "paragraphs": [
            "Refer patients with recurrent or severe sinopulmonary infection, bronchiectasis concern, impaired vaccine responses, IgG subclass abnormalities, low IgG or IgM, lymphocyte abnormalities, anaphylaxis to blood products, or a phenotype raising concern for CVID. The referral question is whether the patient has isolated SIgAD or a broader defect requiring infection prevention or immunoglobulin replacement. [15][18]"
          ],
          "bullets": []
        }
      ],
      "table": {
        "caption": "Presentation-driven evaluation in confirmed or suspected SIgAD. [4][11][15][18][19]",
        "columns": [
          "Clinical branch",
          "Targeted evaluation",
          "Interpretation and action"
        ],
        "rows": [
          [
            "Recurrent sinopulmonary infection",
            "CBC with differential; IgG subclasses; protein and polysaccharide antigen-specific antibody responses; lymphocyte subsets. [15]",
            "Identify coexisting subclass or functional antibody defects; escalate if vaccine responses are impaired or broader immune abnormalities are present. [1][15][18]"
          ],
          [
            "Chronic diarrhea or malabsorption",
            "Giardia testing; total IgA; IgG EMA, IgG DGP, or IgG-tTG if IgA deficient. [4][11]",
            "Do not rely on IgA-tTG alone in IgA deficiency. [11][19]"
          ],
          [
            "Allergic phenotype",
            "Clinical assessment for rhinitis, asthma, eczema, urticaria, conjunctivitis, and food allergy. [19]",
            "Treat the specific allergic disease and continue surveillance for infectious and autoimmune complications. [17][19]"
          ],
          [
            "Autoimmune phenotype",
            "Organ-directed testing for celiac disease, thyroid disease, type 1 diabetes, lupus, arthritis, or cytopenia according to presentation. [18][19]",
            "Manage the identified autoimmune disease while reassessing for associated immune evolution when immunoglobulin abnormalities broaden. [17][18]"
          ],
          [
            "Prior transfusion reaction",
            "Review product exposure and reaction phenotype; evaluate IgA deficiency and involve transfusion medicine before future exposure. [13][15]",
            "Avoid unplanned exposure to standard immunoglobulin preparations in patients at risk for anti-IgA-mediated reactions. [12][13]"
          ]
        ]
      }
    },
    {
      "id": "manage-infections-and-associated-disease",
      "eyebrow": "Treatment selection",
      "heading": "Treat the phenotype, not the IgA value",
      "intro": "There is no replacement therapy that corrects isolated mucosal IgA deficiency.",
      "paragraphs": [
        "For isolated SIgAD without clinically consequential infections or associated disease, do not institute immunoglobulin replacement solely because the IgA concentration is low. IVIG is not indicated when selective IgA deficiency is the only abnormality of concern. [12]",
        "For recurrent bacterial respiratory infections, treat documented infections with pathogen-directed antimicrobial therapy and determine whether impaired specific antibody responses, an IgG subclass deficiency, or evolving CVID is contributing. Prophylactic antibiotics may be appropriate in selected symptomatic patients, particularly those with a severe infectious phenotype; agent choice and regimen should be individualized to infection site, cultures, allergy history, and local resistance patterns. [4][9]",
        "Consider immunoglobulin replacement only rarely and only when there is a justified severe phenotype with an additional clinically meaningful antibody defect. If replacement is used, select an immunoglobulin product with minimal IgA and initiate and monitor treatment under an immunodeficiency-experienced physician because hypersensitivity reactions can occur in patients with anti-IgA antibodies. [9][12]",
        "Treat associated Giardia, celiac disease, allergic disease, and autoimmunity according to the confirmed disorder rather than attributing persistent symptoms to SIgAD alone. In celiac disease, use IgG-based serology for the diagnostic pathway when IgA deficient. [4][11][18]"
      ],
      "bullets": [
        "Do not prescribe standard IVIG for an isolated low IgA level without a separate replacement indication. [12]",
        "Before considering Ig replacement, document quantitative immunoglobulins, IgG subclasses, and functional protein and polysaccharide antibody responses. [15]",
        "Use infection cultures and clinical response to determine whether recurrent respiratory illness is bacterial and whether antibiotic prevention is warranted. [9][15]"
      ],
      "subsections": [],
      "table": {
        "caption": "Management choices by SIgAD phenotype. [4][9][11][12][15]",
        "columns": [
          "Phenotype",
          "Management",
          "Avoid or reassess"
        ],
        "rows": [
          [
            "Asymptomatic isolated SIgAD",
            "Document diagnosis, educate regarding relevant complications, and monitor clinically. [4][15]",
            "Avoid IVIG solely for low IgA. [12]"
          ],
          [
            "Recurrent bacterial respiratory infection with otherwise normal functional evaluation",
            "Treat episodes using microbiologic and clinical data; consider prophylactic antibiotics in selected severe phenotypes. [9][15]",
            "Reassess for functional antibody defects if infections persist or worsen. [15]"
          ],
          [
            "SIgAD plus impaired specific antibody response or IgG subclass deficiency",
            "Immunology-directed prevention; prophylactic antibiotics may be used, and rare cases may justify low-IgA immunoglobulin replacement. [1][9][15]",
            "Do not assume isolated SIgAD; evaluate for broader humoral disease. [18]"
          ],
          [
            "IgA deficiency with suspected celiac disease",
            "Use IgG EMA, IgG DGP, or IgG-tTG rather than an IgA-only serologic strategy. [11]",
            "Do not interpret a negative IgA-tTG as exclusion of celiac disease. [11][19]"
          ]
        ]
      }
    },
    {
      "id": "transfusion-and-immunoglobulin-safety",
      "eyebrow": "Safety critical",
      "heading": "Plan blood-product and immunoglobulin exposure",
      "intro": "The key safety task is identifying patients with a reaction history before another exposure.",
      "paragraphs": [
        "A rare subset of patients with complete IgA deficiency develops anti-IgA antibodies, including IgE anti-IgA antibodies, that can cause severe hypersensitivity or anaphylaxis after IgA-containing blood products or immunoglobulin. A prior anaphylactic transfusion reaction should prompt formal evaluation and transfusion-medicine planning before future transfusion. [4][13][15]",
        "Standard immunoglobulin preparations should not be used casually in SIgAD. IVIG labeling guidance states that true hypersensitivity reactions are rare but may occur in patients with anti-IgA antibodies, and IVIG is not indicated for isolated SIgAD. When an independent replacement indication is established, use a low-IgA product and supervise initiation and monitoring through an experienced immunodeficiency clinician. [9][12]",
        "Place IgA deficiency and any prior transfusion or immunoglobulin reaction prominently in the medical record. For patients with a concerning reaction history, coordinate product selection prospectively with transfusion medicine rather than waiting until urgent transfusion is required. [13][15]"
      ],
      "bullets": [
        "Ask about hypotension, wheeze, urticaria, angioedema, or anaphylaxis during prior transfusion or immunoglobulin exposure. [12][13]",
        "Do not infer that every patient with SIgAD will react to transfusion; focus precautions on complete deficiency and especially those with prior reactions or identified anti-IgA antibodies. [4][12][13]"
      ],
      "subsections": [],
      "table": {
        "caption": "Exposure decisions in patients with IgA deficiency. [4][9][12][13][15]",
        "columns": [
          "Situation",
          "Decision",
          "Reason"
        ],
        "rows": [
          [
            "Isolated SIgAD, no replacement indication",
            "Do not administer IVIG for the IgA deficiency itself. [12]",
            "IVIG is not indicated when SIgAD is the only abnormality. [12]"
          ],
          [
            "Prior anaphylaxis to a blood product",
            "Evaluate for IgA deficiency and coordinate future transfusion planning with transfusion medicine. [13][15]",
            "Anti-IgA antibodies can confer risk of anaphylaxis with IgA-containing products. [13]"
          ],
          [
            "Independent indication for immunoglobulin replacement",
            "Use only after immunodeficiency-experienced supervision; choose a minimal-IgA product when justified. [9][12]",
            "Hypersensitivity reactions are rare but can occur in patients with anti-IgA antibodies. [12]"
          ]
        ]
      }
    },
    {
      "id": "monitoring-and-reclassification",
      "eyebrow": "Longitudinal care",
      "heading": "Monitor for changing phenotype and broader immunodeficiency",
      "intro": "Follow-up intensity should track infectious burden and emergence of immune-mediated disease.",
      "paragraphs": [
        "Monitor symptomatic patients at regular clinical intervals for recurrent sinopulmonary infection, gastrointestinal infection, asthma or allergic rhinitis, and autoimmune disease. Infection is often the earliest manifestation in symptomatic cohorts, with allergic and autoimmune manifestations emerging later; new disease in one domain should prompt reassessment of the others. [4][17]",
        "Repeat quantitative immunoglobulins and functional antibody assessment when infections become more frequent or severe, when new autoimmune disease develops, or when a prior isolated pattern changes. SIgAD can be an early manifestation before subsequent CVID diagnosis; falling IgG, impaired vaccine responses, or reduced memory B cells warrants reclassification rather than continued labeling as uncomplicated SIgAD. [4][18]",
        "Patients with recurrent lower respiratory infections require particular attention because coexisting IgG subclass deficiency and defective antibody responses can identify a higher-risk phenotype. Persisting lower respiratory disease despite standard management should prompt immunology review rather than empiric indefinite treatment as uncomplicated SIgAD. [1][15][19]"
      ],
      "bullets": [
        "At follow-up, document interval infection number, infection site, cultured organisms, antimicrobial courses, hospitalizations, and response to preventive strategies. [9][15]",
        "Reassess celiac disease using IgG-based testing when compatible symptoms arise, and pursue organ-directed evaluation for thyroid disease, type 1 diabetes, lupus, arthritis, or cytopenias when clinically indicated. [11][18][19]",
        "Revisit transfusion precautions at transitions of care and before planned procedures likely to require blood products. [13][15]"
      ],
      "subsections": [],
      "table": null
    }
  ],
  "faq": [],
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  "editorialNote": "Prepared from cited clinical literature using Astra's research workflow. Verify recommendations against current guidance and patient-specific factors.",
  "citations": [
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      "authors": "thorax.bmj.com",
      "host": "thorax.bmj.com",
      "snippet": "IgG subclass deficiency is associated with an increased risk of sino-pulmonary infection in patients with selective IgA deficiency. (IgA concentration less than",
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    {
      "number": 2,
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      "snippet": "Title: P177 Selective ig a deficiency in paediatric recurrent infections – a retrospective study | Archives of Disease in Childhood\n**Background and aims** Abnormal antibody response to polysaccharide proteins found in various bacteria (Haemophilus Influenzae type b, Pneumococcus, Klebsiella Pneumon",
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    {
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      "url": "https://www.sciencedirect.com/science/article/abs/pii/S1521661619303390",
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      "snippet": "### Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). International Federation of Clinical Chemistry. Community Bureau of Refe",
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      "number": 4,
      "title": "The clinical implications of selective IgA deficiency - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S2589909019300255",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "Selective IgA deficiency (SIgAD) is the most common primary immunodeficiency but does not always result in clinical disease. This may in part be due to the definition based on serum IgA, while most IgA is secreted at mucosal surfaces, not amenable to measurement. Clinical complications include incre",
      "score": 0.6989468
    },
    {
      "number": 5,
      "title": "Selective IgA Deficiency: Epidemiology, Pathogenesis, Clinical ...",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/pdf/10.1111/sji.12499",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "The epidemiology, pathogenesis, clinical phenotype, diagnosis, prognosis, management and treatment in patients with SIgAD have been reviewed. Introduction.",
      "score": 0.6549173
    },
    {
      "number": 6,
      "title": "Selective IgA deficiency in early life: Association to infections and allergic diseases during childhood - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/abs/pii/S1521661609006950",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "### J. Allergy Clin. Immunol.\n\n### Transient IgA deficiency and pathogenesis of infantile atopy\n\n### Lancet\n\n### Clinical heterogeneity and reversibility of selective immunoglobulin A deficiency in 80 children\n\n### Lancet\n\n### Genetic approach to common variable immunodeficiency and IgA deficiency\n\n",
      "score": 0.6158511
    },
    {
      "number": 7,
      "title": "Selective Immunoglobulin A Deficiency - ScienceDirect.com",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/immunology-and-microbiology/selective-immunoglobulin-a-deficiency",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "Selective IgA deficiency is defined as the most common form of immunodeficiency, Clinically, it involves undetectable serum IgA levels while maintaining normal",
      "score": 0.6072213
    },
    {
      "number": 8,
      "title": "A novel method to standardise serum IgA measurements shows an ...",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/full/10.1002/cti2.1344",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "With our method to standardize IgA values for laboratory and age differences, we show that IgA deficiency is more prevalent in children less",
      "score": 0.23291197
    },
    {
      "number": 9,
      "title": "Selective IgA Deficiency: Epidemiology, Pathogenesis, Clinical Phenotype, Diagnosis, Prognosis and Management - Yazdani - 2017 - Scandinavian Journal of Immunology - Wiley Online Library",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/full/10.1111/sji.12499",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "Title: Selective IgA Deficiency: Epidemiology, Pathogenesis, Clinical Phenotype, Diagnosis, Prognosis and Management - Yazdani - 2017 - Scandinavian Journal of Immunology - Wiley Online Library\nSelective immunoglobulin A deficiency (SIgAD) is the most common primary antibody deficiency. Although mor",
      "score": 0.84277284
    },
    {
      "number": 10,
      "title": "Immunodeficiency Disorders | Pediatrics In Review - AAP Publications",
      "detail": "publications.aap.org",
      "url": "https://publications.aap.org/pediatricsinreview/article/40/5/229/35282/Immunodeficiency-Disorders",
      "authors": "publications.aap.org",
      "host": "publications.aap.org",
      "snippet": "68. Cassidy. JT. ,. Kitson. RK. ,. Selby. CL . Selective IgA deficiency in children and adults with systemic lupus erythematosus . Lupus . 2007.",
      "score": 0.7458619
    },
    {
      "number": 11,
      "title": "[PDF] Coeliac disease: recognition, assessment and management | NICE",
      "detail": "www.nice.org.uk",
      "url": "https://www.nice.org.uk/guidance/ng20/resources/coeliac-disease-recognition-assessment-and-management-pdf-1837325178565",
      "authors": "www.nice.org.uk",
      "host": "www.nice.org.uk",
      "snippet": "Page 11 of 21 1.7.2 Explain to people with coeliac disease (and their family members or carers, where appropriate) that they may need to take specific supplements such as calcium or vitamin D if their dietary intake is insufficient. 1.7.3 Explain to people with coeliac disease (and their family memb",
      "score": 0.41634628
    },
    {
      "number": 12,
      "title": "[PDF] Guideline on core SmPC for human normal immunoglobulin for ...",
      "detail": "www.ema.europa.eu",
      "url": "https://www.ema.europa.eu/en/documents/scientific-guideline/guideline-core-summary-product-characteristics-human-normal-immunoglobulin-intravenous-administration-ivig-revision-4_en.pdf",
      "authors": "www.ema.europa.eu",
      "host": "www.ema.europa.eu",
      "snippet": " monitoring of serum creatinine levels  avoidance of concomitant use of loop diuretics. Hypersensitivity True hypersensitivity reactions are rare. They can occur in patients with anti-IgA antibodies. IVIg is not indicated in patients with selective IgA deficiency where the IgA deficiency is the on",
      "score": 0.49919498
    },
    {
      "number": 13,
      "title": "[PDF] Guidelines for Preventing Opportunistic Infections Among ... - CDC",
      "detail": "www.cdc.gov",
      "url": "https://www.cdc.gov/mmwr/PDF/RR/RR4910.PDF",
      "authors": "www.cdc.gov",
      "host": "www.cdc.gov",
      "snippet": "Notes: RSV intravenous immunoglobulin is contraindicated among patients with immunoglobulin A deficiency or who might have allergic reactions or anaphylaxis when receiving blood products containing immunoglobulin A (DIII).\nRSV monoclonal antibody is under investigational use among HSCT recipients fo",
      "score": 0.31846446
    },
    {
      "number": 14,
      "title": "Prevention of Hepatitis A Through Active or Passive Immunization: Recommendations of the Advisory Committee on Immunization Practices (ACIP)",
      "detail": "www.cdc.gov",
      "url": "https://www.cdc.gov/mmwr/preview/mmwrhtml/rr5507a1.htm",
      "authors": "www.cdc.gov",
      "host": "www.cdc.gov",
      "snippet": "Serious adverse events from IG are rare. Anaphylaxis has been reported after repeated administration to persons with\nknown immunoglobulin A (IgA) deficiency; thus, IG should not be administered to these persons\n(114). Pregnancy or lactation is not a contraindication to IG administration. [...] Serio",
      "score": 0.25679982
    },
    {
      "number": 15,
      "title": "Selective IgA Deficiency - PMC",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2821513?term=%22J+Clin+Immunol%22%5Bjour%5D",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "IgA deficiency should be a consideration in a patient with recurrent respiratory and gastrointestinal infections, allergies, and autoimmune disorders [1][2]. Immunologic evaluation for IgA deficiency is also warranted in case of anaphylaxis secondary to a blood product transfusion, celiac disease, a",
      "score": 0.82994765
    },
    {
      "number": 16,
      "title": "Selective IgA Deficiency and COVID-19 Outcomes: A Nationwide Retrospective Cohort Study - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13074005",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Serum IgA testing in routine clinical practice is typically performed during evaluation of suspected immunodeficiency, recurrent respiratory or gastrointestinal infections, autoimmune disorders (e.g., celiac disease), or broader immunologic workups. For each individual, the index IgA value was defin",
      "score": 0.82761955
    },
    {
      "number": 17,
      "title": "Understanding the natural history of selective IgA deficiency - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12276590",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "A total of 51 patients (1.2:1 female-to-male ratio) were included, with a median age at diagnosis of 6 years. Infections were the most common clinical manifestations of SIgAD (98 %), with pneumonia being the most frequent (94 %), followed by sinusitis (70 %). Additionally, 47 patients (92.1 %) exhib",
      "score": 0.81489426
    },
    {
      "number": 18,
      "title": "The clinical implications of selective IgA deficiency - PMC",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7388344",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Title: The clinical implications of selective IgA deficiency - PMC\nSIgAD is the most common primary immunodeficiency, and it is defined by the European Society for Immunodeficiency (ESID) as a serum IgA of less than 7 ​mg/dl in patients greater than 4 years old with normal levels of IgG and IgM, nor",
      "score": 0.81204927
    },
    {
      "number": 19,
      "title": "Selective IgA Deficiency - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/sites/books/NBK538205",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "## History and Physical\n\nMost IgA patients remain asymptomatic their whole life. Coincidentally, they are often diagnosed during routine laboratory screening. However, some patients present with different complaints and clinical phenotypes, mainly with recurrent sinopulmonary infection, allergies, a",
      "score": 0.78670514
    },
    {
      "number": 20,
      "title": "Selective IgA Deficiency - StatPearls - NCBI Bookshelf - NIH",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK538205",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "## History and Physical\n\nMost IgA patients remain asymptomatic their whole life. Coincidentally, they are often diagnosed during routine laboratory screening. However, some patients present with different complaints and clinical phenotypes, mainly with recurrent sinopulmonary infection, allergies, a",
      "score": 0.78532547
    },
    {
      "number": 21,
      "title": "Overlapping autoimmunity and immunodeficiency: a case of selective IgA deficiency with autoimmune hemolytic anemia - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12930997",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Keywords: Immunoglobulin A deficiency, Immunodeficiency, Autoimmune hemolytic anemia, Recurrent infection, Case report\n\n## Background\n\nSelective immunoglobulin A deficiency (SIgAD) is the most prevalent form of primary immunodeficiency, affecting males and females equally [1][2]. It is defined as se",
      "score": 0.7777226
    },
    {
      "number": 22,
      "title": "Selective IgA Deficiency May Be an Underrecognized Risk ...",
      "detail": "www.jaci-inpractice.org",
      "url": "https://www.jaci-inpractice.org/article/S2213-2198(22)01043-1/fulltext",
      "authors": "www.jaci-inpractice.org",
      "host": "www.jaci-inpractice.org",
      "snippet": "by R Ameratunga · 2023 · Cited by 14 — Symptomatic sIgAD patients may have recurrent upper respiratory tract infections and sometimes develop allergic or autoimmune disorders, including celiac",
      "score": 0.74363416
    },
    {
      "number": 23,
      "title": "Immunoglobulin A Deficiency - an overview | ScienceDirect Topics",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/immunoglobulin-a-deficiency",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "#### Diagnosis\n\nThe clinical expression of immunodeficiency disorders is primarily infection, related to impaired host defense. Thus, the diagnosis of suspected immunodeficiency involves the evaluation of recurrent, persistent, severe, and otherwise unexplained infections. Many, but not all, immune ",
      "score": 0.5694942
    },
    {
      "number": 24,
      "title": "IgA deficiency: clinical correlates and responses to pneumococcal ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/abs/pii/S152166160300336X",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "Selective IgA deficiency (IgAD) is the most common of the primary immunodeficiencies with a frequency between 1 in 400 and 1 in 2000 [2], [3], [4], [5], [6], [7]",
      "score": 0.5249554
    }
  ],
  "publishedAt": "2026-09-15T17:31:17.718208+00:00",
  "updatedAt": "2026-09-15T17:31:17.718208+00:00",
  "readingMinutes": 6,
  "slug": "selective-iga-deficiency"
}