Parasitic Disease II Flashcards
What type of protozoa can be treated with metronidazole
Bacteria that lack mitochondria
Name
Description
Acquired
Symptoms
Lifecyle
Clinical Disease
Diagnosis
Treatment
Description
Flagellated extracellular protozoan
Acquired
Contaminated food & water
Ingest cysts
Symptoms
Weight loss
Malabsorption
Steatorrhea
Some can be symptomatic
Life cycle
Cysts in water/food
Mature into trophozoites host
Attach to small bowl microvilli
Extracellular lifecycle
Clinical Disease
Chronic infections are asymptomatic
Acute causes symptoms above
Patients with IgA deficiency are at greater risk of infection
Diagnosis
Microscopy – cysts in stool
Fluorescent antibody detection
Treatment
Metronidazole
Filtration necessary to remove cysts – chlorine is not enough
Diagnosted by cysts in the stool
Giardia
Most frequent waterborne disease in USA
Cryptosporidium
Name
Description
Epi
Transmission
Lifecycle
Diagnosis
Treatment
Cryptosporidium
Description
Intracellular parasite
Epi
Most frequent water born disease in USA (CDC)
Symptoms
Immunocompromised – watery diarrhea
Self-limited diarrhea in every one else
Transmission
Infected individuals – fecal oral
Livestock wastes can get into water
Lifecycle
Cyst is infectious & stable in water
Matures and replicates in epithelium of small bowl
Intracellular parasite
Diagnosis
Acid fast cysts
Immunofluorescence antibody detection
Treatment
Nothing good
Nitazoxanide & erythromycin for severely ill patients
Produces an acid fast cyst
Cryptosporidium
Name
Descrition
Symptoms in M & F
Lifecycle
Pathology
Diagnosis
Treatment & prevention
Trichomonas vaginalis
Description
Flagellated protozoan
Trophozoites causes disease
No cyst stage
Presentation in men & women
M=W
Men: Asymptomatic
Women: Frothy purulent discharge urethritis, prostatitis, infertility & low birth weight
Lifecycle
Only 1 stage
Only grow in mucosal cells of the genital tract
Transmitted by sexual intercourse
Pathology
Inflammation increases risk of infection by other STD
Diagnosis
Microscopy – wet prep (women)
Urine & prostate sections (men)
Cytology – Pap stain
Rapid EIA
Molecular assay (PCR most sensitive)
Treatment & prevention
Metronidazole
Must treat sexual partners
Condoms
P. vivex (Answer) - has many different shapes in RBC
P. falciparum only has a ring stage in RBC
Name
Epi (locations for types)
Lifecycle
Clinical presenation
- Incubation (compare)
- Early Symptoms
- Late symptoms
- Complications
Diagnosis (compare)
Why is reinfection common?
3 conditions that confer genetic immunity
Treatment
P. falciparum
Epi
Plasmodium falciparum most verulent
P. falciparum - Tropics
P. vivax – Also in temperent areas because long hepatic stage
Lifecyle
Female anopheles mosquito feeds on a mamal
Sporozoites – infectious form injected into the host
Rapidly multiple in the blood
Enter heptocytes – asytompatic (for up to a year in anopheles but falciparum infection progresses quicker)
Infect RBC – symptomatic
Gametocytes form in RBC can then infect a mosquito
Clinical Presenation
Incubation Period
P. falciparum – 10-40 days
P. vivax – Up to 12 months
First symptoms
Flu-like illness
Fever
Headache
Joint pain
Prostration
Later stages
Shaking chills
Sweats
Initially scyhronized but eventually become periodic
P. f and V – 2 day c
Complications
Cerebral malria – small vessels clogged
Diagnosis
Microscopy – Identify ring stages in RBC & types
Immunochromatographic test with NPV = 99% for p. falciparum
P. falciparum only has a ring stage in RBC
P. vivex has many different shapes in RBC
PCR most sensitive
Immune respionse
Reinfection commen
Slow immune response
Parasite alters surface antigens
Genetic resistance
Sickle cell hemoglobin
Duffy blood antigen
G6PD deficency in RBC
Treatement
Chloroquine
Atovaquone-proguanil
Mefloquine
Artmether-lumefantrine
Quinine
Primaquine used to treat p. viex contraindicated in pateints with GSP defciency
Name
Vector & commonly co-transmitted
Lifecyle
Diagnosis & patient at high risk
Treatment
Babesia
Epi
Spread by ixodes tick
Borrelia burgdorferi
Anaplasma phagocytophilum
Babesia microti
1-3% of patents in endemic areas can have more than 1 infection
Lifecyle
Transmited by white food deer tick – ixodes
Replicates in RBC – see ring ctructures
Slower process of breaking out of the cells so can see extracellular rings which you do not see with maleria
Diagnosis
Microscopy
Starlike cross formations (replicated forms stuck togther) in the RBC
Rings have may different sizes (malaria rings are more uniform)
Aspleic patients have a hiher risk of babesia preasitemia
Treatment
Symtomatic Disease
Atovaquone and Azithromycin
Clindamycin and Quinine
Severe Disease
Exchange tranfusion
p falciparum gametocyte
Name
Description
Lifecycle
Clinical DIsease
- Disease in patients with AIDS
- Risks in pregnany
Diagnosis
Treatment
Epi
15-90% of population infected
Description
Obligate intracellular parasite
Lifecyle
Intracellular protozoan
2 types of Cysts
- Feline gut necessary for sexual cycle which creates cytes that end up in soil or water
- Other strains can form cyctes in livestock
Cysts ingested and mature into tachyzoite/trophozoite which can infect many different cells types
Clinical Disease
Broad range of symptoms
Mono – like
Myocarditis
Hepatitis
Pneumonia
Encephalitis (reactivation stage in patients with AIDS)
Retinitis
Latent infection
Only symptomatic when cysts opens to releast trophozites - necrosis & nflammation
Congenital (mother to child)
CNS (if infected early in pregany) or ocular damage (if infected late in pregnanacy)
Diagnosis
IgG – exposure
IgM – Date infection (important for congental disease risl)
Rarely able to visualize by tissue culture
Treatment
Anti-folate therapy: pyrimethamine-sulfadiazine
