Detection of biofilm related genes, classical enterotoxin genes and agr typing among Staphylococcus aureus isolated from bovine with subclinical mastitis in southwest of Iran.

Staphylococcus aureus by producing biofilm and facilitating chronic infection is a common cause of mastitis in cows and thereby can cause food poisoning by production of enterotoxins in milk. The agr typing method is an important tool for epidemiological investigation about S. aureus. The aims of the present study were to detect biofilm related genes, 5 classical enterotoxin genes and the agr types among S. aureus isolates. The ability of S. aureus isolates to produce biofilm was evaluated by modified CRA plate. Six biofilm related adhesion genes (icaD, icaA, fnbA, bap, clfA and cna), five classical enterotoxin genes (sea, seb, sec, sed and see) and tst-1 gene were detected by PCR methods. Multiplex-PCR was used to determination of the agr groups. 55 out of 80(68.8%) S. aureus isolates were biofilm producer. The icaD gene was detected in 70 (87.5%) of isolates. The prevalence rates of fnbA, icaA, clfA, cna and bap were 72.5, 56.25, 50, 22.5, and 5% respectively. The agr group I and III were detected in 57.5% 25% of studied isolates. The sea, sed and tst-1 genes were found in 10%, 7.5% and 1.25% of isolates respectively. The majority of S. aureus were able to produce biofilm. Significant associations were observed between presence of the icaD, icaA, fnbA, clfA and the cna genes as well as biofilm formation. The present study revealed that isolates with the agr type III are more potent for biofilm production. Our data supported a possible link between the agr types and certain SE genes.

Clinical and Molecular Evaluation of a Case of Giant Primary Splenic Hydatid Cyst: A Case Report.

Spleen is an unusual location for hydatid cyst. Here we report a case of primary splenic hydatid cyst in a 41-yr-old Iranian woman from Yasuj, southwest of Iran. The patient had been admitted to Shahid Beheshti Hospital because of abdominal pain. Abdominal sonography revealed a hypoechoic lesion of 150 X 130 mm in the spleen, suggestive of hydatid cyst. Splenectomy was performed for the patient and surgical interventions revealed a hydatid cyst occupying most of splenic parenchyma. She was discharged on the 5 day of her operation. Postoperative diagnosis and confirmation of hydatid cyst was done by histopathological, molecular and serological approaches. Histopathological evaluation revealed the classical laminated layer of hydatid cyst. DNA was extracted from a part of cyst and PCR amplified. Sequencing and analysis of PCR product revealed that the isolate has the most similarity with G1 strain of Echinococcus granulosus. Patient's serum was positive for IgG anti-hydatid cyst antibodies, using antigen-B ELISA.