Amoebiasis
Definition
An infection caused by anyof the amoebas of the Entamoeba gro;up
Commonly by Entamoeba histolytica.
Incidence
Present all over the world
Transmission
Fecal oral route
Ingestion of the cyst form of the parasite, a semi-dormant form of the parasite in the fecal matter
Fecal contamination of the food & water
Non encyste forms - trofozoites die quickly after leaving the body
Endemic in areas of the world where hygiene is poor
Clinical Features
Mild to severe symptoms
Abdominal pain
Mild diarrhoea
Bloody diarrhoea
Severe colitis
Ulceration of the intestinal mucosa
Tissue death
Dysentery
Diagnosis
Microscopic examination of the stool reveals amoebic cyste and trophozoite forms
Asymptomatic persons - stool is examined by flotation or sedimentation procedures
A minimum of three stool examinations may be neede
Serological tests - antibodies - only after two weeks of the infection - antibodies persist in the blood for years after clinical cure - so only the negtive serological test is more significant
New methods of detection by a kit that detects the presence of ameba proteins in the feces
Detecting ameba DNA in the feces
Complications
Perforation of the amoebic ulcer of the intestinal mucosa - pneumoperitoneum - peritonitis
Iron deficiency anemia
Blood spread - to liver - Amoebic liver abscess - rupture into the pleural cavity - death
Lung abcess, empyema, broncho pleural fistula
Brain abscess, amoebic meningoencephalitis
Cutaneous amoebiasis in skin around sites of colostomy wound, perianal region, at the site of drainage of liver abscess
Amoebic vulvovaginitis, rectovesical fistula and rectovaginal fistula
Malnutrition and stunting of growth
Medical Treatment
Amoebiasis in tissues - Imidazole derivatives like metronidazole (flagyl, metrogyl), tinidazole, nitazoxaide, dehydroemetine or chloroquin
Luminal infection - Dilozanide furoate or iodoquinoline
Prevention
Hand washing with soap and hot running water for at least 10 seconds after using the toilet or changing baby's diaper and before handling food
Clean bathrooms and toilets - toilet seats and taps
Avoid sharing towels or face washers
Avoid raw vegetables in endemic areas
Boil water or treat water with iodine tablets
Avoid eating street foods
Improve sanitation and sewage disposal
Sedimentation and filtration of water since the cysts are resistant to chlorination of water
