Patients deficient in early complement elements have a susceptiblilty to:
a) viruses
b) fungus
c) encapsulated bacteria
d) intracellular bacteria
e) protozoa
f) gonococcus and meningococcus
he correct answer is (c) encapsulated bacteria.
Patients deficient in early complement elements (C1-C4) have a susceptibility to infections with encapsulated bacteria, such as:
– Streptococcus pneumoniae
– Haemophilus influenzae
– Neisseria meningitidis (although late complement components also play a role in defense against this bacterium)
Encapsulated bacteria have a polysaccharide capsule that protects them from phagocytosis. The early complement components help to opsonize (mark) these bacteria for destruction by phagocytic cells. Without these components, the body has a harder time clearing these infections.
The other options are not directly related to deficiencies in early complement elements: