Background: Aeromonas are ubiquitous bacteria causing many clinical conditions including acute diarrhea. Diarrheagenic Aeromonas harbors aerolysin gene secreting virulent enterotoxin, aerolysin.
Objectives: To develop a molecular and immunological based method for detection of
Aeromonas.
Methods: Diarrheal
Aeromonas strains were identified from stool samples using culture, enterotoxicity testing using mice model.
During immune magnetic polymerase chain reaction IM-PCR protocol, aerolysin specific antibodies were bound with immuno
magnetic binding. Sensitivity and specificity tests for IM-PCR were conducted.
Results: There was high detection of
Aeromonas using IM-PCR (12.4 %) technique when compared to low isolation with culture (5.1%). Our study confirmed that some strains of enterotoxic
Aeromonas strains were uncultivable. Enterotoxicity tests on
culture isolates revealed many strains were negative. IM-PCR detected high, (62/500) rate of identification of
Aeromonas with
aerolysin toxin gene.
Aeromonas species identified after IM-PCR were
A. hydrophila
(40.3% ),
A. veronii
(17.7 %),
A. caviae
(14.5 %),
A. trota
(11.2 %),
A. jandei
(9.6 %) and
A. schuberti
(6.4%). All
A. trota strains were undetected by cultivation.
Conclusion: High sensitivity and specificity of IM-PCR are due to preparation of aerolysin antibodies and immuno magnetic
binding, prior to PCR. Since diseases due to
Aeromonas are increasingly reported, IM-PCR is recommended for detection from
clinical specimens.
DOI: https://dx.doi.org/10.4314/ahs.v19i2.27
Cite as: Subbaram K, Gatasheh MK, Al Azzam KM, Kannan H. Molecular identification of diarrheal Aeromonas using immuno magnetic
polymerase chain reaction (IM-PCR) technique: a comparative study with conventional culture method. Afri Health Sci.2019;19(2): 2036-2042.
https://dx.doi.org/10.4314/ahs.v19i2.27 
