Tissue invasion by Entamoeba histolytica: evidence of genetic selection and/or DNA reorganization events in organ tropism.
Entamoeba histolytica infection may have various clinical manifestations. Nine out of ten E. histolytica infections remain asymptomatic, while the remainder become invasive and cause disease. The most common form of invasive infection is amebic diarrhea and colitis, whereas the most common extra-intestinal disease is amebic liver abscess. The underlying reasons for the different outcomes are unclear, but a recent study has shown that the parasite genotype is a contributor. To investigate this link further we have examined the genotypes of E. histolytica in stool- and liver abscess-derived samples from the same patients. Analysis of all 18 paired samples (16 from Bangladesh, one from the United States of America, and one from Italy) revealed that the intestinal and liver abscess amebae are genetically distinct. The results suggest either that E. histolytica subpopulations in the same infection show varying organ tropism, or that a DNA reorganization event takes place prior to or during metastasis from intestine to liver.
Ali
Ibne Karim M
IK
Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom.
Solaymani-Mohammadi
Shahram
S
Akhter
Jasmine
J
Roy
Shantanu
S
Gorrini
Chiara
C
Calderaro
Adriana
A
Parker
Sarah K
SK
Haque
Rashidul
R
Petri
William A
WA
Clark
C Graham
CG
D000818:Animals; D016054:DNA, Protozoan / Q000235:genetics*; D004404:Dysentery, Amebic / Q000469:parasitology; D004748:Entamoeba histolytica / Q000235:genetics / Q000502:physiology*; D005243:Feces / Q000469:parasitology; D005838:Genotype; D006801:Humans; D008101:Liver Abscess, Amebic / Q000469:parasitology; D016133:Polymerase Chain Reaction; D012641:Selection, Genetic / Q000235:genetics / Q000502:physiology*
D016054:DNA, Protozoan