Cytokines Flashcards

Question

CVID

Answer 1

Defect in B-cell differentiation. Cause unknown in most cases May present in childhood but usually diagnosed after puberty increaserisk of autoimmune disease, bronchiectasis, lymphoma, sinopulmonary infections decreaseplasma cells, decrease immunoglobulins

Answer 2

Deficiency of Th17 cells due to STAT3 mutationimpaired recruitment of neutrophils to sites of infection Cold (noninflamed) staphylococcal Abscesses, retained Baby teeth, Coarse facies, Dermatologic problems (eczema), increased IgE, bone Fractures from minor trauma increase IgE increase eosinophils Learn the ABCDEF’s to get a Job!

Answer 3

Mutation in WAS gene; leukocytes and platelets unable to reorganize actin cytoskeleton defective antigen presentation; X-linked recessive WATER: Wiskott-Aldrich: Thrombocytopenia, Eczema, Recurrent (pyogenic) infections increasedrisk of autoimmune disease and malignancy low to normal IgG, IgM high IgE, IgA Fewer and smaller platelets

Answer 4

Defect in lysosomal trafficking regulator gene (LYST) Microtubule dysfunction in phagosome-lysosome fusion; autosomal recessive PLAIN: Progressive neurodegeneration, Lymphohistiocytosis, Albinism (partial), recurrent pyogenic Infections, peripheral Neuropathy ``` Giant granules ( B , arrows) in granulocytes and platelets Pancytopenia Mild coagulation defects ```

Answer 5

Defect of NADPH oxidase decreasedreactive oxygen species (eg, superoxide) and decreasedrespiratory burst in neutrophils; X-linked form most common increasedsusceptibility to catalase ⊕ organisms Recurrent infections and granulomas ``` Abnormal dihydrorhodamine (flow cytometry) test (green fluorescence) Nitroblue tetrazolium dye reduction test (obsolete) fails to turn blue ```

Answer 6

Defect in LFA-1 integrin (CD18) protein on phagocytes; impaired migration and chemotaxis; autosomal recessive Late separation (>30 days) of umbilical cord, absent pus, dysfunctional neutrophils recurrent skin and mucosal bacterial infections increased neutrophils in blood Absence of neutrophils at infection sitesimpaired wound healing

Answer 7

Several types including defective IL-2R gamma chain (most common, X-linked recessive); adenosine deaminase deficiency (autosomal recessive); RAG mutationVDJ recombination defect Failure to thrive, chronic diarrhea, thrush Recurrent viral, bacterial, fungal, and protozoal infections decreased T-cell receptor excision circles (TRECs) Part of newborn screening for SCID Absence of thymic shadow (CXR), germinal centers (lymph node biopsy), and T cells (flow cytometry)

Answer 8

Most commonly due to defective CD40L on Th cells class switching defect; X-linked recessive Severe pyogenic infections early in life; opportunistic infection with Pneumocystis, Cryptosporidium, CMV Normal or high IgM super low IgG, IgA, IgE Failure to make germinal centers

Answer 9

Autoimmune disorder characterized by destruction of exocrine glands (especially lacrimal and salivary) by lymphocytic infiltrates A . Predominantly affects females 40–60 years old. Findings: Inflammatory joint pain Keratoconjunctivitis sicca ( tear production and subsequent corneal damage) Xerostomia (saliva production)mucosal atrophy, fissuring of the tongue B Presence of antinuclear antibodies, rheumatoid factor (can be positive in the absence of rheumatoid arthritis), antiribonucleoprotein antibodies: SS-A (anti- Ro) and/or SS-B (anti-La) Bilateral parotid enlargement Anti-SSA and anti-SSB may also be seen in SLE. A common 1° disorder or a 2° syndrome associated with other autoimmune disorders (eg, rheumatoid arthritis, SLE, systemic sclerosis). Complications: dental caries; mucosa-associated lymphoid tissue (MALT) lymphoma (may present as parotid enlargement); risk of giving birth to baby with neonatal lupus. Focal lymphocytic sialadenitis on labial salivary gland biopsy can confirm diagnosis.

Answer 10

Systemic, remitting, and relapsing autoimmune disease. Organ damage primarily due to a type III hypersensitivity reaction and, to a lesser degree, a type II hypersensitivity reaction. Associated with deficiency of early complement proteins (eg, C1q, C4, C2)clearance of immune complexes. Classic presentation: rash, joint pain, and fever in a female of reproductive age.prevalence in Black, Caribbean, Asian, and Hispanic populations. Antinuclear antibodies (ANA)  Sensitive, nonspecific  Anti Double stranded DNA antibodies  specific  Specific  Seen in 1/3 of patients o Clinical manifestations o Treatments  Avoid sunlight  Glucocorticoids  Other immunosuppressive agents o Drug induced SLE  Antihistone antibodies- characteristic  Hydralazine, procainamide, and isoniazide common causes  Treat: remove drug  Rheumatoid Arthritis  Anti-Sm antibody  Antiphosphlipid antibody  Low complement: C3, C4, CH50 RASH OR PAIN: Rash (malar A or discoid B ) Arthritis (nonerosive) Serositis (eg, pleuritis, pericarditis) Hematologic disorders (eg, cytopenias) Oral/nasopharyngeal ulcers (usually painless) Renal disease Photosensitivity Antinuclear antibodies Immunologic disorder (anti-dsDNA, anti-Sm, antiphospholipid) Neurologic disorders (eg, seizures, psychosis)

Answer 11

 80% positive rheumatoid factor  Antibodies against Fc portion of IgG antibody  “seropositive”  But not specific, other diseases can also have positive rheumatoid factor (SLE, Sjogren’s)  Antibodies to citrullinated peptides (ACPA)  Specific marker for rheumatoid

Answer 12

Systemic sclerosis. Triad of autoimmunity, noninflammatory vasculopathy, and collagen deposition with fibrosis. Commonly sclerosis of skin, manifesting as puffy, taut skin A without wrinkles, fingertip pitting B . Can involve other systems, eg, renal (scleroderma renal crisis; treat with ACE inhibitors), pulmonary (interstitial fibrosis, pulmonary HTN), GI (esophageal dysmotility and reflux), cardiovascular. 75% female. 2 major types: Diffuse scleroderma—widespread skin involvement, rapid progression, early visceral involvement. Associated with anti-Scl-70 antibody (anti-DNA topoisomerase-I antibody) and anti-RNA polymerase III. Limited scleroderma—limited skin involvement confined to fingers and face. Also with CREST syndrome: Calcinosis cutis C , anti-Centromere antibody, Raynaud phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasia. More benign clinical course.

Answer 13

Also called chronic autoimmune thyroiditis. Most common cause of hypothyroidism in iodine- sufficient regions. Associated with HLA-DR3,risk of primary thyroid lymphoma (typically diffuse large B-cell lymphoma). Findings: moderately enlarged, nontender thyroid. May be preceded by transient hyperthyroid state (“Hashitoxicosis”) due to follicular rupture and thyroid hormone release. Serology: ⊕ antithyroid peroxidase (antimicrosomal) and antithyroglobulin antibodies. Histology: Hürthle cells A , lymphoid aggregates with germinal centers B . Postpartum thyroiditis—mild, self-limited variant of Hashimoto thyroiditis arising < 1 year after delivery.

Answer 14

Neoplastic, via chromosomal instability pathway with mutations in APC and KRAS. Tubular B histology has less malignant potential than villous C (“villous histology is villainous”); tubulovillous has intermediate malignant potential. Usually asymptomatic; may present with occult bleeding.

Answer 15

Previously called hereditary nonpolyposis colorectal cancer (HNPCC). Autosomal dominant mutation of mismatch repair genes (eg, MLH1, MSH2) with subsequent microsatellite instability. ∼ 80% progress to CRC. Proximal colon is always involved. Associated with endometrial, ovarian, and skin cancers.

Answer 16

Conceptually, USMLE likes to test on C3b (Innate) and IgG’s (adaptive) roles as opsonins. Opsonization dramatically increases kill efficiency, and thus is important for the general ability of the immune system to function.

Answer 17

Individuals with C1 esterase inhibitor deficiency have an inherently overactive kinin system. The only thing keeping it in check is constant degradation by ACE Giving these patients an ACEi removes the last check on kinin production and can precipitate life threatening edema of the airway mucosa. Note: It is not the angioedema itself that is life-threatening, it is the resulting asphyxiation This classically presents as a patient with no asthma history presenting to the ED with marked swelling and respiratory failure after starting an ACEi. They will ask you something about C1INHµ, or kinin involvement. The Tx is Epinephrine and intubation

Answer 18

Site of B-cell localization and proliferation. In outer cortex. 1° follicles are dense and quiescent. 2° follicles have pale central germinal centers and are active.

Answer 19

Consists of medullary cords (closely packed lymphocytes and plasma cells) and medullary sinuses. Medullary sinuses communicate with efferent lymphatics and contain reticular cells and macrophages.

Answer 20

Contains T cells. Region of cortex between follicles and medulla. Contains high endothelial venules through which T and B cells enter from blood. Not well developed in patients with DiGeorge syndrome. Paracortex enlarges in an extreme cellular immune response (eg, EBV and other viral infections paracortical hyperplasialymphadenopathy).

Answer 21

ontains macrophages and specialized B cells. Site where antigen-presenting cells (APCs) capture blood-borne antigens for recognition by lymphocytes. Located between red pulp and white pulp.

Answer 22

Contains T cells. Located within white pulp.

Answer 23

Contains B cells. Located within white pulp.

Answer 24

Located in the anterosuperior mediastinum. Site of T-cell differentiation and maturation. Encapsulated. Thymus epithelium is derived from third pharyngeal pouch (endoderm), whereas thymic lymphocytes are of mesodermal origin. Cortex is dense with immature T cells; medulla is pale with mature T cells and Hassall corpuscles containing epithelial reticular cells. Normal neonatal thymus “sail-shaped” on CXR (asterisks in A ), involutes by age 3 years. T cells = Thymus B cells = Bone marrow Absent thymic shadow or hypoplastic thymus seen in some immunodeficiencies (eg, SCID, DiGeorge syndrome). Thymoma—neoplasm of thymus. Associated with myasthenia gravis, superior vena cava syndrome, pure red cell aplasia, Good syndrome.

Cytokines Flashcards

(48 cards)