Immunology & Rheumatology syndromes.

Gene/chromosome: WAS, Xp11; Inheritance: X-linked recessive; Triad: Thrombocytopenia with small platelets, eczema, recurrent infections; Associated: Autoimmune disease, lymphoma; Investigation: Low platelet count with small platelets, WAS protein testing

Gene/chromosome: 22q11.2 deletion; Inheritance: Usually de novo, autosomal dominant transmission possible; Triad: Cardiac defects, abnormal facies, thymic hypoplasia, hypocalcemia; Associated: Conotruncal defects, interrupted aortic arch; Investigation: FISH or chromosomal microarray

Gene/chromosome: CYBB (X-linked), or autosomal recessive genes; Inheritance: X-linked or autosomal recessive; Triad: Recurrent catalase-positive infections, granuloma formation, abscesses; Associated: Aspergillus, Staphylococcus aureus, Serratia, Burkholderia; Investigation: Dihydrorhodamine flow cytometry or NBT test

Gene/chromosome: LYST, chromosome 1; Inheritance: Autosomal recessive; Triad: Partial albinism, recurrent infections, neuropathy; Associated: Accelerated-phase hemophagocytic lymphohistiocytosis; Investigation: Giant granules in leukocytes on peripheral smear

Gene/chromosome: ATM, chromosome 11; Inheritance: Autosomal recessive; Triad: Cerebellar ataxia, telangiectasia, recurrent infections; Associated: Lymphoma, leukemia, radiosensitivity; Investigation: ATM testing, AFP, immunoglobulin levels

Gene/chromosome: STAT3; Inheritance: Usually autosomal dominant; Triad: Eczema, recurrent staphylococcal abscesses, markedly elevated IgE; Associated: Pneumatoceles, skeletal/dental abnormalities; Investigation: Serum IgE, STAT3 testing

Gene/chromosome: BTK, Xq22; Inheritance: X-linked recessive; Triad: Recurrent bacterial infections, absent tonsils, very low immunoglobulins; Associated: Enteroviral infections, Giardia; Investigation: Flow cytometry showing absent B cells, low immunoglobulins

Gene/chromosome: Heterogeneous; Inheritance: Usually sporadic; Triad: Recurrent sinopulmonary infections, low IgG, poor vaccine response; Associated: Autoimmune cytopenias, lymphoma, bronchiectasis; Investigation: Quantitative immunoglobulins and vaccine antibody response

Gene/chromosome: IL2RG (X-linked), ADA and other genes; Inheritance: X-linked or autosomal recessive; Triad: Severe infections, chronic diarrhea, failure to thrive; Associated: Opportunistic infections, absent thymic shadow in some forms; Investigation: T-cell lymphopenia, newborn TREC screening

Gene/chromosome: FOXP3, X chromosome; Inheritance: X-linked recessive; Triad: Enteropathy, endocrinopathy, eczema; Associated: Type 1 diabetes, autoimmune thyroid disease; Investigation: FOXP3 testing, regulatory T-cell evaluation

Gene/chromosome: MEFV, chromosome 16; Inheritance: Autosomal recessive; Triad: Recurrent fever, serositis, erysipelas-like erythema; Associated: AA amyloidosis; Investigation: MEFV testing, clinical criteria

Gene/chromosome: SERPING1, chromosome 11; Inheritance: Autosomal dominant; Triad: Recurrent non-urticarial swelling, abdominal pain, laryngeal edema; Associated: Life-threatening airway obstruction; Investigation: Low C4 and C1 esterase inhibitor level/function

Gene/chromosome: Polygenic susceptibility; Inheritance: Multifactorial; Triad: Photosensitivity, arthritis, renal involvement; Associated: Libman-Sacks endocarditis, antiphospholipid syndrome; Investigation: ANA, anti-dsDNA, anti-Sm, complement levels

Gene/chromosome: HLA-DRB1 shared epitope; Inheritance: Multifactorial; Triad: Symmetric inflammatory polyarthritis, morning stiffness, rheumatoid nodules; Associated: Felty syndrome, lymphoma risk, interstitial lung disease; Investigation: Anti-CCP, rheumatoid factor

Gene/chromosome: HLA-B27, chromosome 6; Inheritance: Multifactorial; Triad: Inflammatory back pain, sacroiliitis, reduced spinal mobility; Associated: Acute anterior uveitis, aortic regurgitation; Investigation: MRI sacroiliac joints, HLA-B27

Gene/chromosome: HLA-B27 association; Inheritance: Multifactorial; Triad: Arthritis, conjunctivitisveitis, urethritis; Associated: Enthesitis, circinate balanitis; Investigation: Clinical diagnosis after infection, NAAT for triggering pathogen

Gene/chromosome: HLA-B51 association; Inheritance: Multifactorial; Triad: Recurrent oral ulcers, genital ulcers, uveitis; Associated: Venous thrombosis, aneurysms, neurologic involvement; Investigation: Clinical criteria, pathergy test may support diagnosis

Gene/chromosome: Polygenic susceptibility; Inheritance: Multifactorial; Triad: Dry eyes, dry mouth, parotid enlargement; Associated: MALT lymphoma; Investigation: Anti-Ro/SSA, anti-La/SSB, Schirmer test

Gene/chromosome: Polygenic susceptibility; Inheritance: Multifactorial; Triad: Skin thickening, Raynaud phenomenon, esophageal dysmotility; Associated: Pulmonary arterial hypertension, renal crisis; Investigation: Anti-centromere, anti-Scl-70, nailfold capillaroscopy

Gene/chromosome: No single gene; Inheritance: Acquired autoimmune; Triad: Thrombosis, recurrent pregnancy loss, antiphospholipid antibodies; Associated: Stroke, DVT, pulmonary embolism; Investigation: Lupus anticoagulant, anticardiolipin, anti-β2 glycoprotein I repeated after ≥12 weeks