Parasitology - Classification And Amoeba Flashcards
Types of Amoeba
Intestinal
Free living
Examples of intestinal Amoeba
E. Histolytica
E. Coli
Examples of Free living Amoeba
Naegleria fowleri
Acanthamoeba
Example of Ciliated Parasites
Bolantidium Coli
Example of Flagellated Parasites
Intestine - Giardia lamblia
Genital - Trichomonas vaginalis
Blood and tissue - Leishmania, Trypanosoma
Examples of Sporozoan parasites
Malaria, Babesia
Toxoplasma, Coccidian parasites
Stages of Entamoeba histolytica
3 stages
Trophozoite
Pre-cyst
Cyst - Infective stage
Host in case of Entamoeba histolytica
Humans
Infective form in case of Entamoeba histolytica
Quadrinucleated cyst
Infective dose of Entamoeba histolytica
Small infectivity dose - less than 100 cysts
Entamoeba histolytica cysts can survive in
Chlorination of water
Mode of transmission of Entamoeba histolytica
Feco oral (MC)
Rarely homosexual
Which organisms needs Small infectivity dose
CHHOTA SMALL
C - Cryptosporidium
H - E. Histolytica
H - eHec
S - Shigella
Giardia lamblia
Virulence factor in case of Entamoeba histolytica
Gal/Gal NAC lectin antigen
Enzymes involved in Entamoeba histolytica
Metallo- collagenase
Neuraminidase
Life cycle of Entamoeba histolytica
Ingestion of mature cyst (Feco oral) - Excystation in Small intestine - Formation of 8 trophozoites - Encystation in large intestine - Cyst formation - Cysts nd trophozoites passed in feces - In environment cyst survives - again ingestion
Organs affected in Entamoeba histolytica
Intestine - Travellers diarrhea
Ulcer seen in intestine due to Entamoeba histolytica infection
Flask shaped ulcer - Inside flask - Trophozoites + which engulfed the RBCs (Erythrophagocytosis)
Clinical features of Entamoeba histolytica infection
Asymptomatic intraluminal amoebiasis (M/C)
Amoebic colitis - bloody diarrhea
Complications of Entamoeba infection
Appendicitis
Perforation
Peritonitis
Most common extraintestinal organ involved in Entamoeba infection
Liver - Right lobe (Post superior surface of liver) - leading to Amoebic liver abscess
Gross finding in case of Amoebic liver abscess
Anchory sauce appearance
Microscopic examination finding in Amoebic liver abscess
Trophozoites in pus
Ameboma/Amoebic granuloma involves which region
Chronic condition
Rectosigmoid region
Trogocytosis means
Attachment of Gal/Gal NAC Lectin - killing/Nibbling of cell
Sample taken for diagnosis of Entamoeba
2 stool samples (consecutive days) - intermittent shedding