Severe Combined Immunodeficiency (Scid)



It is caused due to –

  • Deficiency of Adenosine Deaminase (ADA)
  • Adenosine accumulates and converted to ribonucleotides and deoxyribonucleotides (dATP).
  • dATP inhibits ribonucleotidereductase which decreases production of deoxyribose nucleotides.
  • There is decrease in T and B cells leading to immunodeficiency.
  • X Linked Type is the Most Common Pattern of Inheritance

Clinical features-

  •  Chronic diarrhea
  •   failure to thrive.


  • Gene therapy is the first order to be treated.
  • Enzyme Replacement Therapy with Polyethyleneglycol modified bovine adenosine deaminase (PEGADA).

Exam Important

  • There is a decrease in T and B cells.
  • Adenosine accumulation is seen in SCID.
  • DNA synthesis decreases.
  • X Linked Pattren of Inheritance is most common
Don’t Forget to Solve all the previous Year Question asked on SEVERE COMBINED IMMUNODEFICIENCY (SCID)

Module Below Start Quiz

Leave a Reply

Free Mini Course on Stomach

Mini Course – Stomach

22 High Yield Topics in Stomach

in Just 2 Hours

Submission received, thank you!

Close Window
%d bloggers like this:
Malcare WordPress Security