ABSTRACT
Amoebic dysentery (amebiasis) is a parasitic infection caused by Entamoeba histolytica. The diagnosis of invasive amebiasis has traditionally been based on direct and stained microscopic examination of stool samples. Stool microscopy exhibits low sensitivity and it is difficult to distinguish E.histolytica cysts and trophozoites from cells such as leukocytes, macrophages and non-pathogenic Entamoeba species in the stool by microscopy. Therefore more sensitive and specific diagnostic methods such as enzyme linked immunosorbent assay (ELISA) tests which investigate the presence of E.histolytica-specific antigen in stool, and polymerase chain reaction (PCR) are being widely used. In this study it was aimed to study stool samples of the patients who applied with the clinical signs of amebiasis by using direct and permanent stained microscopy, E.histolytica adhesin antigen ELISA test and real-time PCR-based BD Max Enteric Parasite Panel (BD Max EPP) test and to evaluate the diagnostic values of these tests. A total of 546 faecal samples with blood and/or mucus were analyzed in the study. In these samples, the presence of E.histolytica was investigated by direct and permanent stained microscopy, E.histolytica adhesin antigen ELISA and BD Max EPP PCR. Of the samples 36.3% were suspected to contain E.histolytica/dispar/moshkovskii cyst and/or trophozoite by direct microscopic examination. Trichrome staining was performed on these samples and 49 samples were found suspicious for the presence of E.histolytica/dispar/moshkovskii cysts and/or trophozoites. The presence of E.histolytica and other Entamoeba species was not confirmed in 75.2% of the samples. BD Max EPP PCR and E.histolytica adhesin antigen ELISA tests were studied in 49 faecal samples that were suspected by trichrome staining. None of these samples were positive by ELISA. Forty-four samples were negative by PCR and invalid test results were obtained in five samples. In this study, E.histolytica was not detected in the patient population. The results of this study showed that microscopic examination alone is not sufficient for the detection of E.histolytica. It is concluded that it is necessary to use a more sensitive and specific also rapid diagnostic test such as E.histolytica-specific antigen detection test or PCR in the diagnosis of amebiasis to avoid misdiagnosis and unnecessary treatment of patients.
Subject(s)
Amebiasis , Diarrhea , Entamoeba histolytica , Humans , Amebiasis/diagnosis , Diarrhea/diagnosis , Diarrhea/parasitology , Feces/parasitology , Real-Time Polymerase Chain ReactionABSTRACT
BACKGROUND: Because of the emergence and spread of extended-spectrum-beta-lactamase (ESBL)-producing strains which are resistant to many antibiotics, reliable detection of ESBL is very important for infection control. Several chromogenic media have been proposed for the detection of ESBL producers in addition to the conventional phenotypic and genotyping methods. The aim of the present study was to evaluate the performance of Brilliance ESBL agar (Oxoid; Thermo Fisher Scientific, UK), a selective chromogenic agar for the detection of ESBL-producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) strains. METHODS: A total of 237 strains (143 ESBL producers (76 isolates of E. coli and 67 isolates of K. pneumoniae) and 94 non-ESBL producers (44 isolates of E. coli and 50 isolates of K. pneumoniae)) isolated from various clinical specimens were included in the study. Isolates were identified by conventional methods, Phoenix system (Becton Dickinson, USA), and mass spectrometry. ESBL confirmation was performed by phenotypical tests. A 10 microL aliquot of each isolate's 0.5 McFarland suspension was streaked onto Brilliance ESBL agar. All plates were incubated at 37 degrees C for 24 hours and then were interpreted for growth and colony color according to the manufacturer's recommendations. Identification and ESBL test results were used to calculate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the medium evaluated at 24 hours. RESULTS: The sensitivity, specificity, PPV, and NPV of the medium were 97.9%, 100%, 100%, and 96.9%, respectively, when considering only species specific colored colonies of the isolates. CONCLUSIONS: Brilliance ESBL agar could provide a practical alternative to the traditional methods for the identification of ESBL producers.
Subject(s)
Escherichia coli/enzymology , Klebsiella pneumoniae/enzymology , beta-Lactamases/biosynthesis , Culture MediaABSTRACT
OBJECTIVES: Endothelia, intima, and connective tissues comprise the heart valves, but the relationship between heart valve damage, the pathogenesis of valve degeneration, and vitamin D, oxidative stress remains unclear. Here, we assessed serum 25(OH) vitamin D (calcidiol), parathormone (PTH), and redox balance in patients with mitral valve regurgitation (MR) and aortic valve regurgitation (AR). METHODS: This study includes 56 chronic heart valve disease (HVD) patients. Patients were diagnosed with MR or AR depending on the echocardiographic findings. Also, 40 sex-matched healthy control participants were enrolled for comparison. Serum calcidiol, PTH, total oxidative status (TOS), and total antioxidative capacity were measured, and the oxidative stress index (OSI) was calculated. RESULTS: Patients with HVD demonstrated significantly higher PTH, increased TOS and OSI, and a higher frequency of calcidiol deficiency than the control participants. Calcidiol and TOS were negatively correlated (r = -0.29; P <0.005), as were calcidiol and OSI (r = -0.413; P = 0.001). PTH and OSI were positively correlated (r = 0.22; P = 0.02). DISCUSSION: We demonstrate that vitamin D deficiency and secondary increases in PTH are highly prevalent. Heart valve regurgitation (AR and MR) is correlated to oxidative stress and hypovitaminosis D.
