Parasitic/Spirochetal Infections Flashcards
(47 cards)
The transmission of amebiasis is…
Fecal-oral route- the trophozoites invade the mucosa and induce necrosis
About how long is the incubation period for amebiasis?
2-4 weeks. The diarrhea will begin with abdominal pain, distention, tenderness, and hyper peristalsis
- FEVER USUALLY UNCOMMON
Most common group to be infected with amebiasis
Young kids, pregnant, immunocompromised, and those receiving corticosteroids
Amebiasis can present with extra intestinal disease. Describe it
Ameboma- hepatic amebiasis with a liver abscess. Abscesses may rupture causing a fatal prognosis
Clinical findings of amebiasis
- leukocytosis
- hematochezia
- +/- fecal leukocytes
- elevated LFTs if extraintestinal disease
Diagnosis of amebiasis
- stool specimens (at least 3) for occult blood testing, cysts, trophozoites, stool antigen test
- dont be fooled by serology, it stays positive for YEARS after the infection so can’t distinguish an acute infection from an old one.
What is the best way to diagnosis extraintestinal amebiasis such as hepatic ameboma
- serologic tests or anti-amebic antibodies. This can be negative early on, repeat in a week if negative but clinically suspicion high
What should you always rule out before initiated steroid treatment for someone with IBS symptoms?
Amebiasis if in endemic areas! Steroids will worsen the condition
Someone is infected with entamoeba dispar and is asymptomatic. What is the treatment?
- No treatment
What is the treatment for entamoeba histolytica (amebiasis) ?
- metronidazole or tinidazole to eradicate the tissue trophozoites
PLUS
- A luminal amebicide: diloxanide, furoate, iodoquinal, paramomycin
The luminal amebicide iodoquinal should not be used in which patient population?
- those with thyroid disease
- those with kidney disease
Which two luminal amebicides should be avoided in patients with kidney disease?
-iodoquinal and paromomycin
If a patient with intestinal amebiasis can not tolerate metronidazole/tinidazole, what alternative drug can you use?
- tetracycline + chloroquine
If a patient has extraintestinal amebiasis and fails to respond to metronidazole/tinidazole- what can you add to the drug regimen?
- chloroquine, emetine, or dehydroemetine
- aspirate large abscesses
Risk factor for hookworm
- walking barefoot on the beach in tropical/subtropical regions
While most people infected with hookworm are asymptomatic, what is the clinical course of the infection?
- initially: dry cough, wheezing, low grade fever, and eosinophilia during pulmonary migration
- about 1 month later: epigastric pain, anorexia, and diarrhea
What are major complications of a chronic hookworm infection?
- anemia: patient is iron deficient which can lead to weakness, pallor, and heart failure
- protein deficient: hypoalbuminemia, edema ascites
- malnourishment: impairment in growth and development in children
What is “cutaneous large migrans” in relation to a hookworm infection?
- pruritic, maculopapular, often serpingous rash at the site of cutaneous penetration
Treatment for hookworm
- mebendazole/albendazole - not during pregnancy
- 2nd line treatment: pyrantal pamoate and levamisole
Treatment for pinworm
Treat all household members with pyrantel pamoate, albendazole, or mebendazole.
- Treat now and 2 weeks from now after the last eggs have hatched
Malaria typically presents cyclically in three stages. Describe them
- Cold stage - shivering, chills
- Hot stage- fever
- Then finally the sweating stage - diaphoresis
Several different protozoans cause malaria. Describe how the cyclical fevers can be helpful when differentiating the subtypes
- P. Falciparum- constant fever. Most severe form of the disease
- P ovale/vivax - fever spikes q48 hours, these organisms lay dormant in the liver
- P. Malariae - fever spikes q72 hours
General clinical symptoms of malaria
- fever, headache, malaise, chills, N/V/D, dry cough
Complications of P. Falciparum
- Cerebral malaria
- Hyperpyrexia
- Pulmonary edema
- AKI secondary to ATN
- Arrhythmias
- Hemolytic anemia
