Wsu Exam 4 Bacteria Fungus Protozoa Cns Infection

Front 1

What is the famous triad of CNS abscess?

Back 1

Fever

Headache

Focal neurological findings

Front 2

What are the NORMAL ranges of the following in the CSF:

WBC
% PMN
RBC (per uL)
Glucose (mg / dl)
Protein (mg/dl)

Back 2

WBC = 0 – 5

%PMN = 0

RBC (per uL)= 0 – 2

Glucose (mg / dl) = 45 – 85

Protein (mg/dl) = 15 – 45

Front 3

Bug?

-> flu-like symptoms
-> encephalitis
-> psychotic symptoms not unlike schizophrenia

Back 3

Toxoplasma gondii (Toxoplasmosis)

Front 4

What G(+) organisms are most commonly associated with brain abscesses?

Back 4

Streptococcus**
Bacteroides
Peptostreptococcus
Staphylococcus
Nocardia
Actinomyces

Front 5

What are 3 key symptoms of b. burgdorferi?

Back 5

initial skin lesion
can lead to arthritis
neurological problems

Front 6

Bug?

Primary pulmonary infections have no diagnostic symptoms and usually are asymptomatic and lead to latent infection

-> reactivation of latent infection can occur in immunocompromised patients

-> primary infection may remain localized into the lungs or disseminate throughout the body, particularly the CNS

Back 6

Cryptococcus neoformans

Front 7

Disease?

-> headache, drowsiness, confusion, hemiparesis, seizures, or speech difficulties together with fever, but usually NOT a stiff neck

-> often leads to a space occupying lesion, which compresses the normal structures in the brain

Back 7

Polymicrobial abscesses

Front 8

What organism transform into spherical cells called "spherules" in the lung?

An acute respiratory infection occurs 7to 21 days after exposure and typically resolves rapidly.

Back 8

Coccidiodes imitis (Valley Fever)

- once in the lungs, the arthroconidia transform into spherical cells called spherules"

Front 9

What CNS pathogens have a high carriage rate in nose, pharynex, and mouth?

Back 9

Strep. Pneumonia

N. meningitides

H. influenza

Front 10

Bug and disease?

Acquisition: from bite of infected Triatome bug (reduviid bug)

Distribution: From southern US to southern Argentina

Symptoms: initial sore develops at site of insect bite, followed by fever and acute encephalitis, chronic disease can develop years later and affect heart, colon, or nervous system (3% of cases)

Back 10

Trypanosoma cruzi (Chagas Disease)

Front 11

Consists of tightly joined endothelial cells surrounded by glial processes

Back 11

Blood brain barrier = BBB

Front 12

onset of symptoms within hour to several days (sudden)

other sx:
high fever
sever persistant headache
stiff neck
nausea
vomitting

most infections caused by bacterial or viruses

Back 12

Acute meningitis

Front 13

What are the ranges for acute bacterial CSF infection ?

WBC
% PMN
RBC (per uL)
Glucose (mg / dl)
Protein (mg/dl)

Back 13

WBC = > 1000 (neutrophils)

%PMN > 50

RBC (per uL)= 0 – 10

Glucose (mg / dl) < 30

Protein (mg/dl) > 100

Front 14

What organism has the following vaccine?

->contains capsular polysaccharides of 23 serotypes responsible for about 90% of infections

Back 14

23 – valent vaccine for s. pneumo

Front 15

What CNS infection most frequently present with symptoms of:

headache
drowsiness
confusion
seizures
hemiparesis
speech difficulties

-> together with fever with a rapidly progressive course but NOT stiff neck

Back 15

Abscess

Front 16

Bug?

- Majority of acute cases of infection with this fungus follow a subclinical and benign course in normal hosts

- A disseminated and potentially fatal picture is seen among immunosuppressed Individuals

- Dissemination to the CNS results in chronic meningitis or encephalitis

Back 16

Histoplasma capsulatum

Front 17

Consist of endothelium with fenestration and tightly joined choroid plexus endothelial cells

Back 17

Blood CSF barrier = BCB

Front 18

What organism the following virulence factor:

a dark pigment that protects against oxidative defenses of macrophages?

Back 18

organism: Cryptococcus neoformans

virulence factor: melanin

Front 19

Bug?
Acquisition: Inhalation, no person to person spread

Distribution: Endemic to SW US

-> the infection may alternatively result in a chronic pulmonary condition or disseminate to the meninges, bones, joints, and subcutaneous and cutaneous tissues

Back 19

Coccidiodes imitis (Valley Fever)

Front 20

What are the ranges for viral or fungal CSF infection ?

WBC
% PMN
RBC (per uL)
Glucose (mg / dl)
Protein (mg/dl)

Back 20

WBC = 100 – 500 (lymphocytes)

%PMN < 10

RBC (per uL)= 0 – 2

Glucose (mg / dl) < 40

Protein (mg/dl) = 50 – 100

Front 21

Bug?
Acquisition: inhalation

Distribution: Natural reservoirs include pigeon excreta and rotting wood

Risk Factors: Immunosuppression: most common cause of meningitis in HIV+ patients

Back 21

Cryptococcus neoformans -chronic fungal meningoencephalitis

Front 22

What form of Plasmodium falciparum is released form liver cells to infect RBC?

Back 22

MEROZOITES

Front 23

What is the common presentation of Lyme disease associated encephaliis?

Back 23

Aseptic (due to inflammatory response) *** key

aseptic - without contamination with bacteria or other microorganisms

Front 24

How are capsules ( a virulence factor) identified in labs?

Back 24

Serogroups and serotypes

Quellung reaction

India ink stain

Front 25

Bug?

- if untreated leads to dissemination to CNS

- difficulty coordinating muscle movements, paralysis, numbness, gradual blindness, and dementia

Back 25

t. pallidum (3 syphilis)

Front 26

What is the fxn of a capsule as a virulence factor?

Back 26

Prevent complement and antibody deposition

Prevent phagocytosis

Protect intracellularly

Toxic to host cells

Front 27

How do microbes cross BBB &/or BCG?

Back 27

- infect cells that compromise the barrier

- passive transport across in intracellular vacuoles

- carried across by WBC

Front 28

Leading cause of acute bacterial meningitis

Back 28

s. pneumo

Front 29

What microbe has carriage rates of at least < 5% in the nose, pharynx, mouth, GI, & GU?

Back 29

E.coli K1

Front 30

How does a fetus/infant exposed to T. gondii in utero present?

Back 30

- hydrocephalus
- intracranial calcification
- chorioretinitis
- with the possibility of spontaneous abortion or intrauterine death

Front 31

G(-) spirochete

->immunological tests available

-> initial genital chancre sore

-> involves multiplication of the bacteria at the site of entry to produce a localized infection

-> occurs following an asymptomatic period and involves dissemination of the bacteria to other tissues such as CNS

Back 31

T. pallidum

-> bacterial encephalitis

Front 32

Bug?

Acquisition: inhalation of macroconidia from soil

Distribution: central and southern US(Ohio and Mississippi Vally)

Risk Factors: immunosuppression
age < 2 years
elderly
exposure to large inoculums

Back 32

Histoplasma capsulatum

Front 33

What organisms are most frequently associated with brain abscess in patients with AIDS ?

Back 33

Toxoplasma and Cryptococcus

Front 34

What are the virulence factors for TB?

Back 34

The development of TBM is a two step process:

1. M. tuberculosis bacilli enter the host by droplet inhalation, and infect lung macrophages

2. Escalating lung infection = dissemination to blood via lymphatics
-> during this stage there is a short but significant bacteremia that results in dissemination to the CNS

Front 35

Bug?

-> G(-) spirochete

-> microaerophilic

-> difficult to culture

-> requires special medium (BSK-II)

-> must use serological tests with variable reliability

Back 35

Borelia burgdorferi (lyme disease)

Front 36

What virulence factor associated with Cryptococcus neoformans degrades host phospholipids and aids in tissue destruction and cellular escape?

Back 36

Phospholipase B

Front 37

What bugs are assoc with bacterial encephalitis?

Back 37

Borrelia burgdorferi (lyme disease)

Treponema pallidum (3 symphilis)

Front 38

How are localized suppurative infection within the brain diagnosed?

Back 38

This refers to Polymicrobial abscesses

Diagnosis:
->CT scan recommended prior to lumbar puncture due to risk of brain herniation, 4-5 days

-> abscess is surrounded with a fibrous capsule

-> results in the famous ring-enhancing appearance n CT examination with contrast

Front 39

What is the infectious stage of T. gondii?

Back 39

Cats = oocyst with sporozoites

other hosts = pig, sheep, mouse = tissue cyst with bradyzoite

Humans ingest oocyst with sporozoites or tissue cyst with bradyzoites

Front 40

What CNS infection may erroneously suggest meningitis due to neuro exam which may reveal a stiff neck on occasion?

Back 40

abscesses

Front 41

In what form does T. gondii cause encephalitis?

Back 41

Tissue cysts develop, especially in the brain and cause encephalitis

Front 42

What type of vaccine for n. meningitides is recommended for ages 11 – 55?

Back 42

Meningococcal conjugate vaccine (MCV4)

Front 43

What are the cause of common neonatal acute bacterial meningititis?

Back 43

S. agalactiae (GBS): G(+) cocci in chain

L. monocytogenes: G(+) bacilli

E. coli K1: G(-) bacillis

Front 44

What are the virulence factors for Listeria Monocytogenes?

Back 44

-> invasion (InlA and InlB)

->intracellular survival (Hly)

-> cell-to-cell spread (ActA)

->escape from host cell vacuoles (LLO, Listeriolysin O)

Front 45

Adhesion virulence factor of Streptococcus pneumonia which binds to CHO on cell surface?

Back 45

CpbA

- other adhesion virulence factor: PspA

Front 46

What risk factors are associated with polymicrobial abscesses of the brain?

Back 46

Immunocompromised & distal infection (sinusitis, otitis media)

Front 47

What form of p. falciparm is taken up by a mosquito from human host and what form is in injected in human host?

Back 47

Gametocytes

Sporozoites – infectious of p. falciparm

Front 48

Bug?

Gram (-) pleomorphic coccobacilli
->facultative anaerobe

- can be encapsulated (typeable) or nonencapsulated (nontypeable)

- fastidious growth & nutrient requirements

- grows on Chocolate agar,

-requires: Factor V: nicotinamide adenine nucleotide (NAD) & Factor X: hemin

Back 48

H. Influenza type B

Front 49

What does T. gondii transform into to cause spread throughout the body?

Back 49

In host, transform into tachyzoites are released and spread throughout the body

Front 50

What organism has the following vaccine contains 7 capsular polysaccharides that are most prevalent in
-children
-immunocompromised
-elderly patients

Back 50

7 – valent vaccine for s. pneumo

Front 51

What bug is associated with chronic bacterial meningitis?

Back 51

M. tuberculosis

Front 52

What virulence factors are associated with n. meningitdis?

Back 52

IgA protease

Pili – adherence to epithelium

LOS - like LPS (toxic and pro-inflammatory)

Capsule (A, B, C, Y, W 135)

Front 53

Bug?

G(+) cocci in chains
Catalase (-)
Beta-hemolytic
(+) CAMP hemolysis test
Capsule

Back 53

GBS or Strep Agalactiae

Front 54

Bug?

G(-) cocci, generally in pairs (diplococci)

Fastidious: chocolate agar, Oxidase (+)
Ferments glucose and maltose

Back 54

Neisseria meningitides

Front 55

What organism presents with the following symptoms?

->infection have characteristic pyogranulomatous microabscesses diagnosed as “granulomatosis infantiseptica”

-> infants will also often have microabscesses on the liver

Back 55

Listeria moncytogenes

Front 56

What post-neonatal bacterial meningitis organism has the following virulence factors:

- Capsule
- IgA protease
- Pili
- Endotoxin
- Outer membrane proteins (OMP)

Back 56

H. Influenza

hint:
hat is like a cap outside

Hint 56

hat is like a cap outside

Front 57

Bug & disease?

- fetus infected in utero and development of systemic infections (including bacteriemia, puemonia, and meningitis)

- occurs during first 6 days of life (mean age of 12 hours)

Back 57

GBS (strep agalactiae)

-> Early onset disease

Front 58

What are the risk factors associated with outbreaks of meningitis at colleges and universities?

Back 58

poor eating habits

alcohol use

smoking

pulmonary infections

-> changes in immune function and microbiota composition

Front 59

What are the virulence factors associated with Guillain Barré Syndrome?

Back 59

- infection occurs after ingestion of as few as 800 organisms

-> chemotaxis, motility, and flagella: attachment and colonization of the gut epithelium,

-> other possible virulence determinants are iron acquisition, host cell invasion, toxin production, and epithelial disruption

Front 60

Pregnant woman has Listeriosis, what ae are seen in fetus?

Back 60

Infected pregnant women may experience flu-like illness.

Fetus can have microabscess on skin, liver, spleen, lung, and brain.

infection can lead to miscarriage or still birth, or premature delivery

Front 61

What organisms are associated with a capsule as a virulence factor?

Back 61

Streptococcus pneumonia

Neisseria meningitides

Haemophilus influenza

GBS

Cryptococcus neoformans

Front 62

What post-neonatal bacterial meningitis organism has the following virulence factors:

Capsule
IgA protease
pneumolysin
autolysin
CpbA
PspA

Back 62

S. pneumo

Front 63

Bug?

G(-)curved rods
-microaerophilic
-motile

Back 63

Campylobacter jejuni

Front 64

What post-neonatal bacterial meningitis organism has the following virulence factors:

Capsule
IgA protease
Pili
Endotoxin

Back 64

n. meningitis

Front 65

Bug?

Gram (+)yeast

India Ink (+) -> (negative stain for capsule)

Calcofluor White (+) ->(fungal stain)

Urease (+) -> (also a virulence factor)

Capsular antigen detected in CSF or serum

Back 65

Cryptococcus neoformans

Front 66

What 2 bugs can be acquired from unpasteurized dairy?

Back 66

L. mono and E. coli K1

Front 67

Bug & disease?

fetus colonized during birth and infection ( primarily meningitis) at 7 days to 3 months

Back 67

GBS - late onset disease

Front 68

Bug?

- after initial infection, dissemination leads to inflammatory response and characteristic skin lesion at site of insect bite

- bacteria spread hematogenously within days and result in systemic inflammation response

- after several months, bacteria can localize in certain tissues (CNS, skin, joints)

Back 68

Borelia burgdorferia - bacteria encephalitis

Front 69

What are the virulence factors associated with E. coli K1?

Back 69

K1 capsule (Kps proteins): composed of K1 Ag, antiphagocytic & serum resistant

LPS

Front 70

What are the most common organisms recovered from Polymicrobial Abscesses in the brain?

Back 70

Streptococcus anginosus group (US)

Streptococcus milleri group (Europe)

Synergy with anaerobic organisms

Front 71

What are the virulence factors for GBS?

Back 71

Capsule (Csp protein)

ATP protease (Clp protein)

Front 72

What 2 protien does Ab to C. Jejuni cross react with in periperial nervous system and what is the result of the cross rxn?

Back 72

microbial gangliosides and neural antigens

immunologic attack upon peripheral nerve myelin due to crossreactivity between microbial gangliosides and neural antigens

Front 73

What bug enters the body by droplet inhalation, infects the lungs, spread to the blood and can enter the cns?

Back 73

M . Tuberculosis

Front 74

What G(-) organisms are associated with Polymicrobial brain abscesses?

Back 74

Prevotella

Fusobacterium

Escherichia coli

Citrobacter koseri

Proteus mirabilis

Front 75

What CNS infection has the following sx?

sudden fever
headache
vomiting
abnormal visual sensitivity to light
stiff neck and back
confusion
drowsiness
clumsiness
unsteady gait
irritability

Back 75

Encephalitis

Front 76

Bug?

Gram (-)bacilli
Ferments lactose (Pink on MacConkey)
Oxidase (-)

Back 76

Ecoli K1