Waterhouse Friedrichson syndrome has which immune component deficient?
And infections with what organisms are the especially susceptible to?
No, just meningococcal
And just neisseria? Ideally, shouldn't there be increased susceptibility to all gram -ve organisms?
It is caused due to haemorrhage in adrenal gland. Waterhouse is not just a primarily immune complex deficient state. It is a manifestation of systemic infection due to meningococcal meningitis
Umm. My book says that patients with meningococcemia who develop Waterhouse..... Are generally MAC deficient.
There isn't susceptibility to other gram negatives because membrane attack complex is a defense against bacteria which can survive intracellularly.
So basically, extracellular lysis by MAC is effective in killing only Neisseria species.
You're susceptible to N. meningitis only because Neisseria gonorrhea has an outer membrane protein. MAC interacts with it and fails to insert in the bacterial membrane.
And then E. Coli and Salmonella have long polysaccharide chains in cell wall and these side chains prevent the insertion of MAC into bacterial membrane.
So MAC is good at killing only one thing - N. meningitidis and the deficiency will predispose you to this one infection only!
If you're talking about an infection that hemorrhages into the adrenals - it has to get really out of control to do that. And MAC deficient patients can't control their Neisseria infections leading to Water House Friedreichson syndrome. So the book is fair in saying those who develop WHFS due to meningococcal infections are usually MAC deficient.