Immunology 👾 Flashcards
Cells with specialized antigen presenting functions-
BMD – B lymphocytes, Macrophages, Dendritic cells
Most abundant antibody in serum
IgG
Which antibody can cross placenta-
IgG
Which antibody acts as an opsonin-
IgG1 & IgG3
(Fc segments)
Which antibody is particularly important in defence against polysaccharide antigens-
IgG2
Highly effective at neutralizing toxins-
IgA
Which antibody is most abundant in external secretions-
IgA
Antibodies present in external secretion
GAM
Antibodies that act through complement activation-
GM
Which antibody is most efficient in complement activation-
IgM
Which antibody has highest molecular weight-
IgM
Important in defence against parasite infection-
IgE
Function in B cell development-
IgD
First antibody that is produced following exposure to a new antigen-
IgM
IgM appears in serum after-
5-10 days
Following subsequent re-exposure, lag time between exposure and production of antibody is decreased to-
2-3 days
During re exposure with same antigen, antibody response is dominated by-
IgG
After production of IgM, production of other antibodies takes –
1-2 weeks
Additional input from T lymphocyte to produce antibodies is required in-
Primary antibody response
Predominant antibody in mucosal surface-
IgA
Direct biomarker of acute inflammation-
CRP
CRP is synthesized by-
Liver
CRP acts as-
BAO
( biomarker, APR, Opsonin)
Following an inflammatory stimulus, circulating concentrations of CRP rises within –
6 hours
Half life of CRP-
18 hours
Sequential measurements of CRP is useful for-
monitoring disease activity
Sensitive early indicator of acute phase response-
CRP
Indirect measure of inflammation-
ESR
Reliable marker of inflammation-
Plasma viscosity
Conditions associated with normal CRP & raised ESR:
LUPUS OME
L= SLE
U= Ulcerative Colitis
P= Pregnancy
U
S=Sjogren Syndrome
O= Old age
M=Multiple Myeloma
E=ESRD
Conditions associated with raised CRP & raised ESR:
Bacterial infection ( Acute, Necrotising,Chronic)
Viral infection (Acute)
Fungal infection (Acute,Chronic)
Localized abscess
Bacterial endocarditis
Tuberculosis
Crohn’s Disease
Polymyalgia Rheumatica
Inflammatory Arthritis
Acute inflammatory diseases
Anti inflammatory cytokines are-
Interleukin-4
Interleukin-10
TGF-B
Pro inflammatory cytokines are-
Interleukin-1,2,6,8,17,23
TNF-Alpha
Interferon-Gamma
Interleukins causing fever-
IL-1
IL-6
TNF-alpha
T cell deficiency causes infection with which bacterias?
Mycobacterium tuberculosis
Atypical mycobacteria
T cell deficiency causes infection with which fungi-
Candida
Aspergillus
Pneumocystis jirovecii
Infection with M.tb or atypical mycobacteria may suggest which immunodeficiency?
T lymphocyte deficiency
Phagocyte deficiency
Staph aureus infection occurs in which immunodeficiency
1)Phagocyte deficiency
2)Antibody deficiency
Phagocyte deficiency causes infection with:
No(Nocardia)
Burkha (Burkholderia)
Stephanie (Staph A)
Candy (Candida)
To
Sera (Serratia)
As per (Aspergillus)
Pseudo (Pseudomonas)
Tv (TB-Mtb+atypical)
T cell deficiency causes infection with-
L= lung( Aspergillus)
Y
M= MTB+ atypical TB
P=Pneumocystis jirovecii
H=HZV, HPV, HHV ( not HIV)
O
C=Candida
Cytomegalovirus
Cryptosporidia
Y
T=Toxoplasma gondii
E= EBV
Complement deficiency causes infection with
NHS
Neisseria meningitis
Neisseria gonorrhoeae
Hemophilus influenzae
Streptococcus pneumoniae
Antibody deficiency causes infection with-
HSSG
Hemophilus influenzae
Streptococcus pneumoniae
Staphylococcus aureus
Giardia lamblia
common sites of chronic granuloma formation-
BULLS
Lung, lymph nodes, soft tissue, bone, skin, urinary tract
Most common site of granuloma-
Lungs
Most common primary antibody deficiency
Selective IgA deficiency
Recognized complication of common variable immune deficiency
Bronchiectasis
Diseases associated with common variable immune deficiency
ITP
Autoimmune Hemolytic Anemia
Lymphoproliferative Diseases
In all Primary immune deficiency which vaccines should be avoided-
Live
Treatment of choice in severe combined immune deficiency?
Stem cell transplantation
Patients in whom T lymphocyte deficiency is suspected,they should be screened for-
HIV
Half life of IgG
21 days
Hyperimmune globulin is used in-
R-PET VH-PEP C-PI
1) Rabies (post exposure treatment)
2) Hepatitis B (post exposure prophylaxis)
3) Varicella Zoster ( post exposure prophylaxis)
4)Cytomegalovirus ( as prophylaxis in immunosuppressed/transplant patients)
Recurrent cough+ diarrhea=?
Selective IgA deficiency
Defective/No antibody response to polysaccharide antigen
Specific antibody deficiency
Patients with complement deficiency should be vaccinated with-
Meningococcal vaccine
Pneumococcal vaccine
H.influenzae B vaccine
Prevention of meningococcal infection-
Lifelong prophylactic penicillin
Patients with T lymphocyte deficiency should be considered for –
Anti-pneumocystis and anti-fungal prophylaxis
Physiological causes of secondary immune deficiency-
Age
Pregnancy
Prematurity
Infections causing secondary immune deficiency-
HIV
Measles
Mycobacterial infections
Drugs causing secondary immune deficiency-
Anti-epileptic drugs
Stem cell transplantation
Radiation injury
Immunosuppressants
Anti cancer drugs
Glucocorticoids
Sources of Interferon-alpha?
T cell
Macrophage
(ATM)
Sources of interferon-gamma?
T cell
NK cell
(GTN)
Resident cells of lymph node?
Cortex- B cell
Paracortex- T cell, Dendritic cell
Medulla-Plasma cell,Macrophages
Primary/Azurophil granules of the neutrophils contain which enzymes?
Myeloperoxidase
Secondary granules of the neutrophil contain-
LLC
L= Lysozyme
L=Lactoferrin
C=Collagenase
Opsonins include-
CRP
IgG
C3b
Phagocytes include-
Macrophage
Monocyte
Neutrophil
Cells of the innate immunity system-
1)Neutrophil
2)Eosinophil
3)Basophil
4)Monocyte
5)Macrophage
6)Mast cell
7)Natural Killer cell
Cells of the adaptive immune system-
1)B cell
2)T cell
3)Antigen presenting cell
Components of both innate & adaptive immune system-
1)NK cell
2)Macrophage
3)Complement
Mucosal immunity-
Th17
Acute/Positive phase reactants are-
CRP
Amyloid A
Fibrinogen
Alpha-1 Antitrypsin
Alpha-1 Antichymotrypsin
Haptoglobin
Manganese Superoxide Dismutase
Ferritin
Lactoferrin
(CAFe LaTTe)
Negative phase reactants-
(Increased in chronic inflammation)
Albumin
Urea
Factors helping in Resolution of inflammation-
TGF-Beta
PDGF
Chronic inflammation is frequently associated with-
Normocytic normochromic anemia
(anemia of chronic disease)
Which mineral deficiencies cause secondary immune deficiency
Iron
Zinc
Examples of periodic fever syndromes-
1)FMF
2)Mevalonate Kinase Deficiency
3)TNF Receptor Associated Periodic Syndrome (TRAPS)
4)Cryopyrin Associated Periodic Syndrome (CAPS)
Most common form of familial periodic fever-
FMF
FMF occurs due to mutation in-
MEFV gene
Pyrin protein
Recurrent episodes of fever lasting for hours to 4 days which is painful + abdominal pain+ chest pain+ arthritis + markedly elevated CRP =?
FMF
Major complication of FMF
AA Amyloidosis
Treatment of FMF:
1) Colchicine
2) Anakinra
3)Canalikumab
H/O chronic infection ( TB, Bronchiectasis, OM) or chronic inflammation( RA, FMF) + features of nephrotic syndrome=?
Reactive (AA) Amyloidosis
Multiple myeloma
+ SOB, features of HF ( R.Cardiomyopathy)
+ Tingling numbness (peripheral neuropathy) =?
Light chain amyloidosis (AL)
Known case of ESRD + pathological fracture+ joint pain + carpal tunnel syndrome=?
Dialysis associated Amyloidosis
(AB2M)
Pathognomonic feature of light chain amyloidosis
Macroglossia 👅
Hereditary amyloidosis inheritance pattern-
AD
Diagnosis of amyloidosis is established by-
Rectal or subcutaneous biopsy
Pathognomonic Histological finding of amyloidosis
🍏Apple green birefringence of amyloids when stained with congo red dye 🍷
Diseases associated with type 3 cryoglobulinemia
Hepatitis C
Rheumatoid arthritis
SLE
Type 3 cryoglobulin is
Polyclonal IgM or IgG formed against constant region of IgG then forming immune complex
Key investigation in the assessment of patient suspected of having allergy
Skin prick testing
Disadvantages of skin prick testing-
1) Remote risk of severe allergic reaction
2) Unreliable result in patients with extensive skin disease
3) Antihistamines inhibit the magnitude of response
4) Antihistamines should be discontinued for at least 3 days before test
5) Low dose glucocorticoids do NOT influence test results
6) Amitriptyline , Risperidone gives false negative results
Extremely useful in investigating a possible anaphylactic event
Serum mast cell tryptase
Following a systemic allergic reaction,Circulating levels of mast cell degranulation products rise dramatically to peak after-
1-2 hours
MOA of Omalizumab
Monoclonal antibody directed against IgE
Properties of angioedema
Episodic
Localized
Non pitting swelling of submucous or subcutaneous tissue
Key mediator of idiopathic angioedema
Histamine
Key mediator of hereditary angioedema
Bradykinin
Key mediator of ACEI associated angioedema
Bradykinin
Causes of idiopathic angioedema-
Hypothyroidism
NSAIDS
Opioids
Radiocontrast media
Inheritance pattern of hereditary angioedema-
AD
Pathophysiology of hereditary angioedema
Inherited C1 inhibitor deficiency
Adolescent male + facial swelling +/- SOB w H/O dental procedure or trauma or infection+ Family H positive=?
Hereditary Angioedema
Investigation for hereditary angioedema?
Acute- C4 levels : low
Confirm dx- C1 inhibitor levels
Treatment of hereditary angioedema
Acute attack:
1) C1 inhibitor concentrate
2) Bradykinin receptor antagonist: Icatibant
Prevent attack: Anabolic steroid- Danazol
Prophylaxis: Tranexamic acid
Classification of transplant rejection according to time
Minutes to hours- Hyperacute
5-30 days- Acute cellular
5-30 days- Acute Vascular
>30 days- Chronic
Pathological finding of hyperacute rejection
Thrombosis
Necrosis
Pathological findings of chronic allograft failure
Fibrosis
Scarring
Most common form of graft rejection
Acute cellular rejection
Major adverse effects of calcineurin inhibitors-
1)Increased susceptibility to infection
2)Hypertension
3)Nephrotoxicity
4)Diabetogenic (specially Tacrolimus)
5)Gingival hypertrophy (Ciclosporin)
6)Hirsutism (Ciclosporin)
Major complications of long term immunosuppression
Infection
Malignancy