12.2 Infectious Disease Pathology

Question 1

where do you find bacterial meningitis?

Answer 1

subarachnoid space

Question 2

what does “encephalitis” really mean?

Answer 2

infection within the brain parenchyma

Question 3

when an infection involves both the brain parenchyma and the subarachnoid space

Answer 3

meningoencephalitis

Question 4

what are microglial nodules? where are they seen?

Answer 4

small aggregates of chronic inflammatory cells (elongated microglial cells) viral encephalitis

Question 5

bacteria and cut inflammation of the CSF circulating in the subarachnoid space is called:

Answer 5

bacterial meningitis

Question 6

the CSF in bacterial meningitis shows: ________ protein, __________ glucose, ________, ___________

Answer 6

increased, decreased bacteria neutrophils

Question 7

what are the short term and long term complications of bacterial meningitis?

Answer 7

short term: edema and vasculitis long term: subarachnoid fibrosis (hydrocephalus)

Question 8

when do you see fibrosis in the brain?

Answer 8

brain abscess

Question 9

in a brain abscess, you see a _________ center with _____, a ring of ________ _______ around and surrounding ______ and ______

Answer 9

necrotic, pus granulation tissue fibrosis and edema

Question 10

what does a brain abscess look like on imaging?

Answer 10

a ring-enhancing lesion

Question 11

what causes a brain abscess?

Answer 11

direct implantation or spread of bacteria to the brain

Question 12

what are the features of an acute abscess histologically? Chronically, you can see _______.

Answer 12

neutrophil collection fibrosis

Question 13

usually viral infections in the brain are (choose one): encephalitis, meningoencephalitis, just meninges

Answer 13

meningoencephalitis

Question 14

histologically, what are most viral meningoencephalitis infections characterized by?

Answer 14

perivascular lymphocytes and microglial nodules

Question 15

herpes simplex type 1 causes necrosis and hemorrhage of the ________ lobes

Answer 15

temporal

Question 16

what do you see in imaging of Herpes encephalitis?

Answer 16

light colored lesions on the temporal lobes

Question 17

what is the most likelt diagnosis

Answer 17

herpes encephalopathy

Question 18

what do you see in histology of herpes encephalitis?

Answer 18

perivascular inflammation

Cowdry type A intracellular inclusions

Question 19

what are these?

what disease is this?

Answer 19

Cowdry type A intracellular inclusions

herpes encephalitis

Question 20

how does HIV make its way to the brain?

Answer 20

by attaching to CD4 on macrophages, which serve as a reservoir

Question 21

what is distinct that is seen in HIV encephalitis?

Answer 21

multinucleated giant cells in a perivascular location

Question 22

what does this show?

what infection is this most likely?

Answer 22

perivascular giant cells

HIV encephalitis

Question 23

most of the patients that get fungal infection of the brain are ____________. The fungi are _________.

Answer 23

immunocompromised

opportunisic

Question 24

cryptococcal meningitis is caused by what?

Answer 24

a budding yeast, cryptococcus

Question 25

what disease grossly produces “soap bubbles” in the brain?

Answer 25

cryptococcal meningitis

Question 26

what is this?

Answer 26

cryptococcal meningitis

Question 27

what do you see in imaging in someone with cerebral toxoplasmosis?

Answer 27

ring enhancing lesions

Question 28

cerebral toxoplasmosis: opportunistic infection caused by __________ _______

Answer 28

toxoplasma gondii

Question 29

microscopically, cerebral toxoplasmosis is seen as:

Answer 29

necrotic lesions surrounded by acut and chronc inflammation and macrophages

also, cysts characteristic of it

Question 30

what does the arrow show

Answer 30

cyst characteristic of toxoplasma gondii

Question 31

acute inflammatory cells (neutrophils) are most common in: __________ infections

Answer 31

bacterial infections