Comparative profiling of agr locus, virulence, and biofilm-production genes of human and ovine non-aureus staphylococci.

BACKGROUND: In a collaboration between animal and human health care professionals, we assessed the genetic characteristics shared by non-aureus staphylococci (NAS) infecting humans and dairy ewes to investigate their relatedness in a region concentrating half of the total National sheep stock. We examined by PCR 125 ovine and 70 human NAS for biofilm production, pyrogenic toxins, adhesins, autolysins genes, and accessory gene regulator (agr) locus. The microtiter plate assay (MPA) was used for the phenotypic screening of biofilm production. Ovine NAS included S. epidermidis, S. chromogenes, S. haemolyticus, S. simulans, S. caprae, S. warneri, S. saprophyticus, S. intermedius, and S. muscae. Human NAS included S. haemolyticus, S. epidermidis, S. hominis, S. lugdunensis, S. capitis, S. warneri, S. xylosus, S. pasteuri, and S. saprophyticus subsp. bovis. RESULTS: Phenotypically, 41 (32.8%) ovine and 24 (34.3%) human isolates were characterized as biofilm producers. Of the ovine isolates, 12 were classified as biofilm-producing while the remaining 29 as weak biofilm-producing. All 24 human isolates were considered weak biofilm-producing. Few S. epidermidis isolates harbored the icaA/D genes coding for the polysaccharide intercellular adhesin (PIA), while the bhp, aap, and embp genes coding biofilm accumulation proteins were present in both non-producing and biofilm-producing isolates. Fifty-nine sheep NAS (all S. epidermidis, 1 S. chromogenes, and 1 S. haemolyticus) and 27 human NAS (all S. epidermidis and 1 S. warneri) were positive for the agr locus: agr-3se (57.8%) followed by agr-1se (36.8%) predominated in sheep, while agr-1se (65.4%), followed by agr-2se (34.6%) predominated in humans. Concerning virulence genes, 40, 39.2, 47.2%, 52.8, 80 and 43.2% of the sheep isolates carried atlE, aae, sdrF, sdrG, eno and epbS respectively, against 37.1, 42.8, 32.8, 60, 100 and 100% of human isolates. Enterotoxins and tsst were not detected. CONCLUSIONS: Considerable variation in biofilm formation ability was observed among NAS isolates from ovine and human samples. S. epidermidis was the best biofilm producer with the highest prevalence of adhesin-encoding genes.

Multi-parasite infection in an immigrant from Ghana: potential for new epidemic foci.

INTRODUCTION: Imported parasitosis, which do not require an invertebrate vector, are extremely dangerous and can lead to the occurrence of disease in currently parasite free areas. In the present study we report a case of multi-parasitic infection in a young immigrant from Ghana to Italy caused by filaria, Schistosoma sp. and Strongyloides sp. CASE PRESENTATION: A 27-year-old Ghanaian man attended the Hospital of Nuoro (Sardinia), Italy, at the end of August 2015, claiming pain to the kidney and hypertensive crisis; the patient presented with dyspnea and epistaxis, chronic itchy skin of the back, shoulders, arms and legs, anuria and high creatinine, metabolic acidosis and hypereosinophilic syndrome. Serological test for parasitic infections were done, and showed a marked positivity for filaria, Schistosoma sp. and Strongyloides sp. The patient started the treatment immediately with two doses per day of Bassado Antibiotic (tetracycline) for twenty days and then with a single dose of 3 mg of ivermectin that was repeated after 3 months. CONCLUSIONS: Immigrant patients from endemic areas who show clinical signs, such as a general itching on the back, shoulders and arms and legs, should have a thorough history in order to make early diagnosis and prevent further complications. Therefore, general practitioners and doctors in Europe and in other parasitosis non-endemic countries, should consider to test for parasites in any immigrant from endemic countries to aid in establishing the final diagnosis and prevent further complications.

Association of N176K and L141F dimorphisms of the PRNP gene with lack of pathological prion protein deposition in placentas of naturally and experimentally scrapie-affected ARQ/ARQ sheep.

The placenta is important in the horizontal transmission of the aetiological agent in scrapie-affected sheep. It has been demonstrated that the placentas of fetuses carrying the dimorphism Q171R of the PRNP gene is resistant to pathological prion protein (PrP(Sc)) accumulation in the placenta. To test whether other PRNP polymorphisms are associated with a lack of placental PrP(Sc) deposition, we carried out a study on 26 naturally and 11 experimentally scrapie-affected ewes with or without clinical signs. PrP(Sc) was detected in the placenta of ARQ/ARQ(wild type) fetuses by Western blot and immunohistochemical analysis, but not in ARQN(176)/ARQK(176) or, as expected, ARQ/ARR samples. Furthermore, three of four AL(141)RQ/AF(141)RQ placentas were also PrP(Sc) negative, suggesting that the dimorphism at codon 141 may also mediate placental deposition of PrP(Sc). This finding demonstrates for the first time that fetal PRNP polymorphisms, other than those at codon 171, are associated with the lack of placental deposition of PrP(Sc).