Hello and welcome to the Zero to Finals podcast. My name is Tom and in this episode I'm going to be talking to you about complement disorders.

And if you want to follow along with written notes on this topic, you can follow along at 0.orgonels.com slash complement disorders or in the immunology section of the zero definals pediatrics book.

So let's get straight into it.

Complement disorders affect the complement proteins that make up the complement system,

which helps to destroy pathogenic cells.

Compliment proteins are most important in dealing with encapsulated organisms,

such as hemophilus influenza B, streptococcus pneumoniae, and nyseria meningitis.

First let's talk about complement deficiencies.

Deficiencies in complement proteins result in a vulnerability to certain infective organisms

leading to recurrent infections with these organisms.

Complement deficiencies make children particularly susceptible to infections of the respiratory

tract, ears and throat.

They're also associated with immune complex disorders such as systemic lupus erythematosis,

as an incomplete complement cascade leads to immune complexes building up and being deposited in

tissues leading to chronic inflammation. C2 deficiency is the most common complement deficiency.

Vaccination against encapsulated organisms is very important in managing patients with complement

deficiencies. Next let's talk about C1 esterase inhibitor deficiency, which is also known as hereditary angiadema.

Bradikinin is a part of the inflammatory response.

It's responsible for promoting blood vessel dilatation and increased vascular permeability,

leading to angiadema.

Part of the action of C1 esterase is to inhibit bradychinin.

An absence of C1 esterase in C1 esterase deficiency causes intermittent angiadema in response to

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