Malaria Flashcards
What is the infectious form of malaria?
Sporozoites. Injected from mosquito
Where does malaria travel within host?
First, liver, then RBCs.
What’s unique about vivax?
It’s got a “resting stage” in the liver. Can stay dormant for months
How does malaria cause disease?
Infects RBCs, which lyse and release new infectious forms. Causes fevers and eventually gametocytes
What is the incubation period for malaria?
10-40 days
What are the sx of malaria?
Fever spikes, headache, arthralgia, chills, sweats
Why is falciprum an emergency?
Can progress rapidly–well to death in 6 hrs. In a feverish ill traveler, falciprum should be at the TOP of your differential
What is a serious complication of malaria?
Cerebral malaria, where cells clog the venules causing coma.
How do you diagnose malaria?
blood films
dipstick
PCR
Why is it hard to develop immunity to malaria?
The surface antigen is always changing and a vaccine is not available
What would protect you from malaria? What would increase your risk?
sickle cell protective
G6PD deficiency protective
Duffy blood antigen increases your risk
How do you treat malaria?
Chloroquine and primaquine.
How do you get babesia?
From ticks
What do you see on blood film of babesia?
Both INTRA and EXTRAcellular ring forms that look like malaria. MALTESE CROSS is classic
How do you treat babesia?
If asymptomatic, do not treat.
- -Atovaquone and azith
- -Clindamycin and quinine.
–Consider a transfusion is serious
How does babesia present?
With nonspecific symptoms and fever
What would u see on smear of falciprum?
banana form. Aside from that, they should ALL be rings. Vivax has many different forms.
What is the technical name for the pin worm?
Enterobius vermicularis
What is the dx stage for pinform?
The perianal egg
WHat is the diagnostic stage of ascaris?
egg in the feces. These are destroyed by sunlight or dehydration.
What is the clinical presentation of ascaris?
light infection=malabsorption
heavy infection=intestinal obstruction or hemorrhagic pneumonitis w/ N/V/abdominal pain
Most are ASYMPTOMATIC!
Where does strongyloides mature in the human host?
Within the alveoli of the lungs. Once they are coughed up and swallowed, they mature again in the intestines.
What is the hyperinfection cycle of stronyloides?
Newly laid eggs hatch and stay in the intestine rather than being excreted in the feces
How do you get strongyloides?
From walking barefoot
How do you diagnose visceral larva migrans?
antibodies to worm antigens and liver biopsy. You will NOT see eggs in the stool!
What causes cuteanea larva migrans?
the dog/cat hookworm
Which type of schisto likes the bladder in particular?
S. hematobium
How do you tell apart the three different types of schistos?
mansoni has one spine poking out to the side
hematobium has a pointy hat
japonicum is round
How long does schisto live in your system?
DECADES. THey use human antigens to avoid the immune system
How long is the incubation period with schisto?
6 weeks
What is the one “key word” with schisto?
PIPESTEM fibrosis of the liver
What key constellations of sx would make you suspect schisto?
eosinophilia
hepatosplenomegaly
bloody vomit
hematuria
FRESH WATER CONTACT
What is the name for the pork tape worm? Who is the definitive host?
taenia solium.
Human are the definitive host. They live in our guts. In pigs, they stay in the muscle. You can get it from eating undercooked pork.
–cysticercosis is life threatening
What’s the diagnostic stage of giardia?
cyst in stool OR trophozoite in diarrhea
How do you diagnose toxo?
sabin-feldman dye test
Elisa
PCR
Symptoms of toxo?
myalgia, headache, fever
-encephalitis, myocarditis, hepatitis
If perinatal infection, blindness and mental retardation
What do you give to a pregnant mom who is asymptomatic but positive for toxo?
Chemo (spiramycin) during pregnancy
Sulfadiazine after birth
Can you have a latent crypto infection like with toxoplasma?
NO–must be a new infection. Cannot be reactivated
What are the most serious sequelae of falciprum?
- cerebral malaria (headache/coma/paralysis)
- GI hemorrhage
- Tubular necrosis in the kidneys
- ->All of these stem from micro infarcts
What is unique about the blood smear in plasmodium vivax?
- Large, infected reticulocytes
- All forms seen
- ROUND not banana gametocytes
- Schuffner’s dots
What do you use for malaria prophylaxis?
Mefloquine
What drug is effective for P vivax in particular?
Primaquine
HOw do you treat babesia?
atovaquone + azithro or clindamycin
Where does vivax sleep?
In the liver
What would you see in the blood tests of someone with falciprum (no smear)
Decreased hgb (hemolytic anemia) Decreased platelets (thrombocytopenia) Increased creatinine (acute renal failure)
In a patient with influenza, what common OTC is absolutely contraindicated?
Aspirin–Can cause Reyes syndrome!
How do you treat strep throat?
Penicillin. If allergic, use erythromycin
What are pneumonia red flags?
hilar adenopathy
heart failure
diffuse infiltrate (viral/atypical)
Upper lobe infiltrate with granulomas
