Immuno Def Disorders

Question 1

Immuno def disorders

Answer 1

These diseases include diverse spectrum of illness that arise from lack or abnormality of immune system

Question 2

Basic clinical manifestation

Answer 2

Frequent , prolonged, severe infections caused by micro organism with low pathogenicity

Question 3

Classification if idd

Answer 3

1. Primary idd
2. Secondary idd

Both involve
B cell deficiency
T cell deficiency
Combined b and t cell deficiency
Complement deficiency
Phagocytic deficiency

Question 4

B cell deficiency

Answer 4

1. X linked hypogammaglobulinemia or brutons agammaglobinaemia
   ( very low level of all classes of ig produced.
   Recurrent pyogenic bacterial infection eg. Otitis media, sinusitis, pneumonia in infants)
2. Selective immunodeficiencies- isolated iga deficiency
3. Hyper igm syndrome

Question 5

T cell deficiency

Answer 5

1. Thymic aplasia: di george syndrome
   (Profound def of t cells
   Both thyroid and parathyroid glands fail to develop properly in embryonic life
   Several viral fungal protozoal inf in infants. Not bacterial because b cell is not affected)
2. Chronic mucocutaneous candidiasis

Question 6

Combined t and b cell def

Answer 6

Severe combined immunodeficiency disease scid
Recurrent infection caused by bacteria virus fungi protozoa in early infancy
Immunoglobulins are low
Tonsils and lymph node are absent

Question 7

Complement deficiency in pr

Answer 7

Autoimmune diseases like sle

Question 8

Phagocytic
Deficiency

Answer 8

1. Chronic granulomatous disease
2. Chediac higashi disease- pt is susceptible to opportunistic inf with certain bact and fungi
   Fusion of phagosome and lysosome is inhibited

Question 9

Pattern recognition receptor deficiency

Answer 9

1. Receptors on the surface of innate immune cells - def of tlr 5 results in failure of recognizing flagellin on bacteria and marked susceptibility to legionella infection
2. Receptors within innate immune cells
   NOD receptors in cytoplasm recognise peptidoglycan of gram + and -ve bact
   Mutation of nod is associated with diseases related to gut barrier immunity

Question 10

In secondary b cell def

Answer 10

1. Severe malnutrition
2. Asplenia- reduced supply of aa and reduced synthesis of igG leading to pyogenic bact inf
3. Pts suffer from recurrent sinusitis
   Pneumonia

Question 11

T cell def in sec

Answer 11

1. AIDS due to greatly reduced t cell number caused by hiv
   Hiv will kill cd4 t cell so both cmi and hi is lost
   Opportunistic inf in pts with aids
2. Measles.. pts with transient suppression of cmi.
   Quiscent TB becomes active

Question 12

Complement def in sec

Answer 12

1. Liver failure- alcoholic cirrhosis and chr hep B or C
2. Malnutrition- decreased supply of AA leads to decreased synthesis of complement in liver

Question 13

Phagocytic def in sec

Answer 13

Neutropenia..
These pts present with severe infection caused by pyogenic bacteria and enteric gram -ve rods
Neutrophile <500 /ul predispose to infection.
It is due to use of cytotoxic drugs in
cancer chemotherapy
Leukemia
Autoimmune destruction of neutrophil

Question 14

Predisposing factors for sec idd

Answer 14

Skin disorders like burn or eczema
Malnutrition
Loss of protein- nephrotic synd and protein loosing encephalopathy
Urinary catheterization
IV cannulation
Artificial prosthetics
Antibiotic therapy
Cancers
Immuno suppresive drugs like steroids

Question 16

Basic clinical manifestation

Answer 16

Frequent , prolonged, severe infections caused by micro organism with low pathogenicity