Free Living Amoeba Flashcards
primary amebic meningoencephalitis (PAM
Naegleria
Survive and replicate in the envi without a host, no insect vectors, etc Infection of humans is infrequent but is life threatening
Free living amoeba
granulomatous amebic encephalitis (GAE) and amebic keratitis Affects immunocompromised individuals
Acanthameba
GAE, affects primarily healthy individuals
Balamuthia
GAE + granulomatous skin and lung lesions, primarily healthy individs Sappinia diplidea Single case report (encephalitis
Balamunthia mandrillaris
Naegleria Life Cycle
free living flagellate form, not in body but in
Environment
Naegleria
dormant, form protective covering on itself for preservation from harsh surroundings
Cyst
Naegleria
pathogenic/infective/infective stage, inhaled directly through nasal mucosa descriptively termed lopopods (Naegleria pseudopods, rounded) Found in human brain
Amoeboid trophozoite
Naegleria
found in fresh water lakes and ponds, esp warm water
ubiquitous genes
Free living amoebas, instead of pseudopode
Lobopodes
PAM recognized by
Fowler
PAM initially thought to be
Acanthamoeba
Naegleria
Invasive reproductive form, penetrate nasal mucosa and cribriform plate during inhalation or aspiration
Trophozoite
Naegleria
Free living form
Flagellate
Neutrophils surround the trophozoite
Naegleria
Incubation period of PAM
1-14 days
PAM symptoms usually within a few days after swimming in
Warm still water
PAM is indistinguisable from?
Bacterial meningitis
Symptoms of PAM
Headache
Lethargy
Disorientation
Coma
PAM is rapid clinical course, death in _____ after onset of symptoms
4-5 days
PAM
Can be detected in spinal fluid but diagnosis is usually autopsy
Trophozoite
Dagnosis of PAM
Leukocytosis/hyperglycemia
PCR/DNA
CT scan of head
Lumbar puncture
PAM lumbar puncture
Increase pressure increase CSF protein N or low glucose Break WBC Gram stain negative ameba Wet amount of fresh CSF
PAM
No drug of choice but survivors were treated with
Ampotericin B
PAM mortality rate
> 95%
Mae/female 3/1
PAM new drug
Azithromycin
No flagellate form
Acanthamoeba spp