10. Infections 2: Fungal, Protozoal, & Spirochetes

Question 1

Where does histoplasmosis typically come from?

Answer 1

Mississippi and Ohio river valleys

Question 2

How does histoplasmosis grow in the body?

Answer 2

As a mold that converts to a yeast above 37 degrees

Question 3

What are the major systemic signs/symptoms of histoplasmosis?

Answer 3

TB-like granulomatous infection

Question 4

What are the ocular findings of histoplasmosis?

Answer 4

Histo-spots
PPA
CNVM
*No vitritis

Question 5

What type of organism is histo?

Answer 5

Fungus

Question 6

What does malaria infect?

Answer 6

Red blood cells

Question 7

What causes the fever, chills and rigors associated with malaria?

Answer 7

Release of cytokines when RBCs rupture

Question 8

Patients with what conditions are protected from malaria?

Answer 8

Hemoglobin S
Hemoglobin C
Thalassemia

Question 9

What are the ocular signs of malaria?

Answer 9

Roth spots, CWS, mac edema

Conj pallor, hemes

Question 10

Retinal hemes are prognostic signs for what type of malaria?

Answer 10

Cerebral malaria

Question 11

What are the 4 differentials for Roth Spots?

Answer 11

Anemia
Bacterial endocarditis
Leukemia
Malaria

Question 12

What type of organism of Toxoplasmosis?

Answer 12

Intracellular protozoan

Question 13

How does toxo get around?

Answer 13

Oocysts are shed from the intestines of cats, brds, and other mammals

Question 14

What 2 things are found in humans that can cause toxo?

Answer 14

Cysts

Trophozoites

Question 15

What symptoms are seen in acquired toxo?

Answer 15

Mostly asymptomatic

May have lymphadenopathy

Question 16

How is congenital toxo passed?

Answer 16

Trans-placental

Question 17

What are the common CNS signs of congenital toxo?

Answer 17

Cerebral calcification
Seizures
Encephalitis

Question 18

What are the ocular signs/symptoms of toxo?

Answer 18

Microphthalmia
Cataracts
Scleritis
Acute uveitis

Question 19

What are the common retinal findings in toxo?

Answer 19

Bilateral macular scars in childhood
Chorio-retinitis
CME
RD
Vasculitis
Neo
Vitritis - headlights in fog

Question 20

Active IgM antibodies from toxo can persist for how long?

Answer 20

Up to 1 year

Question 21

What test/change is indicative of recent toxo infection?

Answer 21

Seroconversion from negative to positive IgG

Question 22

What tests are used to confirm toxoplasmosis infection?

Answer 22

Toxo DNA by PCR analysis of CSF

PTOX/PCR

Question 23

When is IgG not useful for diagnosing?

Answer 23

In infants under 6 months

Question 24

What types of drugs are used to Tx toxo?

Answer 24

Combos - pyrimetamine and sulfa
Clindamycin and sulfa
Trimethoprim and sulfa

Question 25

In immuno-compromised pts, stereoids should never be used without what?

Answer 25

Antimicrobials

Question 26

In primary syphilis, where does Chancre occur?

Answer 26

At the inoculation site

Question 27

What disseminates through the body in secondary syphilis?

Answer 27

T Palladium

Question 28

What produced the dermatologic, ocular, and constitutional manifestsions of secondary syphilis?

Answer 28

T Palladium

Question 29

What does tertiary syphilis cause?

Answer 29

Aortitis Gummata Uveitis, retinitis, optic neuritis Neurosyphilis

Question 30

What are the common signs of congenital syphilis?

Answer 30

``` Clutton's joints Sabre shins Snuffles Saddle nose Frontal bossing Mulberry molars Rhagades Hutchinson's triad ```

Question 31

What is Hutchinson's triad?

Answer 31

Mulberry molars Deafness Interstitial keratitis

Question 32

What are the ocular signs of syphilis?

Answer 32

Conj chncre Interstitial keratitis Salt and pepper fundus Argyll-Robertson pupil

Question 33

What labs can be done for syphilis?

Answer 33

RPR, VDRL Darkfield microscopy Direct fluorescent antibody (DFA) Biopsy

Question 34

When might RPR and VDRL be non-reactive, but syphilis is actually present?

Answer 34

Early in disease Latency HiV

Question 35

Why isn't penicillin useful for tertiary syphilis?

Answer 35

Does not reach high levels in the eye or CNS

Question 36

What are the neurologic/cardiac signs of Lyme?

Answer 36

CN VI palsy | Bell's palsy

Question 37

What ocular findings are seen in chronic Lyme?

Answer 37

Episcleritis Keratitis Granulomatous KPs Pars planitis/vitritis

Question 38

What are the ocular signs/symptoms of rocky mountain spotted fever?

Answer 38

Conj suffusion | Bilateral periorbital edema