Listeria monocytogenes in spontaneous abortions in humans and its detection by multiplex PCR.
OBJECTIVE
To assess the extent of Listeria monocytogenes in causation of human spontaneous abortions by isolation methods and PCR analysis for the presence of virulence-associated genes.


RESULTS
A total of 305 samples comprising blood, urine, placental bits, faecal and vaginal swabs were collected from 61 patients with spontaneous abortions. Listeria spp. were isolated from 10 samples collected from nine (14.8%) patients. Confirmation of these isolates was based on biochemical tests, haemolysis on blood agar, CAMP test, phosphatidylinositol-specific phospholipase C (PI-PLC) assay followed by in vivo pathogenicity tests and multiplex PCR to detect virulence-associated genes (prfA, plcA, hlyA, actA and iap). Three isolates were confirmed as L. monocytogenes. Of these, two isolates turned out to be pathogenic and found to posses all five genes. However, the remaining two haemolytic L. monocytogenes isolates lacking the plcA gene and activity in the PI-PLC assay were found to be nonpathogenic by in vivo tests.


CONCLUSIONS
The occurrence of pathogenic L. monocytogenes in cases of spontaneous abortions was 3.3%. It seems that the plcA gene and its expression have an important role as essential virulence determinants in pathogenic Listeria spp.


CONCLUSIONS
The recovery of pathogenic L. monocytogenes isolates from cases of spontaneous abortion indicates the significance of listeric infection in pregnant women.
Kaur
S
S
Division of Veterinary Public Health, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
Malik
S V S
SV
Vaidya
V M
VM
Barbuddhe
S B
SB
D000022:Abortion, Spontaneous / Q000382:microbiology*; D000818:Animals; D016470:Bacteremia; D015373:Bacterial Typing Techniques; D002642:Chick Embryo; D005243:Feces / Q000382:microbiology; D005260:Female; D005516:Food Microbiology; D005798:Genes, Bacterial; D006801:Humans; D008089:Listeria monocytogenes / Q000235:genetics / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology*; D010920:Placenta / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D014556:Urine / Q000382:microbiology; D014621:Vagina / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics
D037521:Virulence Factors