Diseases Flashcards
Congenital asplenia
No defense against blood-borne pathogens
Howell-Joly bodies indicate lack of function
C5-C9 or properdin deficiency
Associated with increased susceptibility to infections by neisseria
(Doesn’t totally knock out complement function)
Immune complex disease
Deficiencies in C1, C2, C4
Aggregation and precipitation of immune complexes at basement membrane
Systemic lupus erythematous
Deposition of IgG autoantibodies against DNA
Characteristic butterfly rash
Mixed essential cryoglobulinemia
Common in patients with chronic hep C infections
Hereditary angioedema
Result of a C1INH deficiency
Chronic activation of complement leads to production of C2 kinin, causing extensive swelling
Factor I deficiency
Uncontrolled convertase activity results in C3 depletion–>reduced complement fixation–>reduced bacterial clearance–>patients more susceptible to encapsulated bacterial infections
Paroxysmal nocturnal hemoglobinuria
CD59 deficiency–>constant MAC pore formation
Sunlight triggers RBC hemolysis
Severe hemolytic anemia
TLR3/TRIF deficiency
Causes recurrent herpes simplex virus encephalitis
MyD88 deficiency
Lack of inflammatory cytokine production
Patients develop severe infections by pyogenic bacteria
Cannot develop fever
NEMO deficiency
Hypohidrotic ectodermal dysplasia
Susceptible to pyogenic bacteria
Characteristic abnormalities of ectoderm-derived tissues
Conical-shaped teeth
Septic shock
Systemic bacterial infection induces macrophages to release TNF-a, leading to massive leakage of fluid into body tissues
Disseminated intravascular coagulation
TNF-a causes increased blood flow, vascular permeability, and endothelial adhesiveness of WBCs and platelets leading to blood clots in venules
Severe congenital neutropenia
Deficiency of neutrophils at birth or soon after
Life-threatening pyogenic infections, acute gingivostomatitis, chronic periodontal disease
Leukocyte adhesion deficiency
Problem in recruiting neutrophils
Mutations of integrin beta chain
Recurrent skin infections, periodontal disease, delayed wound healing, candidiasis
Leukocytosis–increased WBC count
Chronic granulomatous disease
Caused by mutations in NADPH oxidase enzyme complex
Heightened susceptibility to infections by intracellular bacteria
Form granulomas due to inability to kill phagocytosed bacteria
No respiratory burst after phagocytosis
XLA
X-linked agammaglobulinemia
Lack of functional Bruton’s tyrosine kinase
No circulating B cells and no antibodies
DiGeorge Syndrome
Microdeletion in chromosome 22q11.2 CATCH-22 Cardiac abnormality Abnormal facies Thymic aplasia Cleft palate Hypocalcemia/hypoparathyroidism
Autoimmune lymphoproliferative syndrome (ALPS)
Mutation in Fas gene leading to uncontrolled lymphocyte proliferation in the absence of infection or malignancy
Splenomegaly and lymphadenopathy; later autoimmunity and lymphoma
IPEX
Absence of T-reg cells
Immune dysregulation, polyendocrinopathy, enteropathy X-linked disease
Agammaglobulinemia
total lack of B cells
Hyper IgM syndrome
defect in AID gene
susceptible to pyogenic infections
Severe combined immunodeficiency disease
total lack of T cells
B cells can’t function without T cells, so loss of both humoral and cell-mediated immunity
Omenn syndrome
type of SCID
Mutations in RAG gene lead to decreased enzyme activity
X-linked Hyper IgM Syndrome
CD40L deficiency
Cell-mediated and humoral defects
No class-switching