Pathogenic Intestinal Amoeba

• Entamoeba histolytica 


  Causes:

  = Intestinal and Extraintestinal Amoebiasis or AMOEBIC DYSENTERY
• Entamoeba histolytica

  Incubation:

  = highly variable can range from 4 DAYS to 4 MONTHS
• Entamoeba histolytica

  Infective form:

  = MATURE QUADRINUCLEATE CYST passed in feces of CONVALESCENT and CARRIERS
• Entamoeba histolytica

  Habitat:

  = COLON
• Entamoeba histolytica

  Mode of Transmission or MOT

  = Man acquires infection by SWALLOWING FOOD and CONTAMINATED WATER with CYST.
• PATHOGENESIS

  Clinical Manifestations for Intestinal Amoebiasis:

  = Stools are LARGE, FOUL SMELLING, and BROWNISH BLACK

  = with BLOOD-STREAKED MUCUS intermingled with feces.

  = The RBCs in stools are clumped and REDDISH-BROWN in color.

  = Presence of CHARCOT-LEYDEN CRYSTALS
• PATHOGENESIS

  Clinical Manifestations of Hepatic Amoebiasis:

  = LIVER ABSCESS

  = Contains THICK CHOCOLATE BROWN PUS (Anchovy sauce pus is the example and may look like)
• PATHOGENESIS

  Laboratory Diagnosis:

  = STOOL EXAMINATION

  Treatment

  = Paromomycin

  = Diloxanide furoate (Furamide)

  = Metronidazole (Flagyl)
• CYST of Entamoeba histolytica

  = Size: 10-20 um

  = With fine even PERIPHERAL CHROMATIN

  = Usually with 1-4 NUCLEI

  = THIN nuclear membrane

  = Contains: CHROMATID BODIES or CHROMIDIAL BARS

  = Resistant to GASTRIC ACIDITY & DESICCATION

  = Encyst in the SMALL INTESTINE liberating 8 TROPOZOITES that proceed to the COLON
• TROPOZOITE of Entamoeba histolytica

  = Size: 10-60 um

  = With finger-like, SHARPLY POINTED PSEUDOPODS

  = Progressive, rapid, and UNIDIRECTIONAL MOVEMENT

  = With fine even PERIPHERAL CHROMATIN

  = Cytoplasm: GROUND GLASS APPEARANCE

  = Hallmark: Presence of INGESTED RBCs