Diagnosis of Trichomonas vaginalis infection: The sensitivities and specificities of microscopy, culture and PCR assay.

OBJECTIVES: The aim of this study was to compare wet mount-, Giemsa stain-, acridine orange fluorescent stain-, cultivation- and polymerase chain reaction (PCR)-based approaches to establish which method or combination of methods was most effective in the laboratory diagnosis of trichomoniasis. STUDY DESIGN: Out of 200 investigated patients with various gynecological complaints, Trichomonas vaginalis infection was detected in 27 (13.5%) by any of methods investigated. Among women with trichomonads, a typical clinical finding was presented in only nine. For analysis of sensitivity and specificity of the methods used, the receiver operating characteristic (ROC) curve concept with culture as a gold standard was applied. RESULTS: Infection was diagnosed by wet mount in 14 (7.0%) women, by Giemsa stain in 11 (5.5%) and by acridine orange stain in 16 (8.0%) women. In 21 (10.5%) women, it was diagnosed by culture in Diamond's medium, and in 22 (11.0%) by PCR. For the initial diagnosis of trichomoniasis, wet preparation is the test that is widely available in most STD clinics, but its sensitivity is poor (66.67%). Giemsa stain shows a low sensitivity of 52.38%. Acridine orange shows reasonable sensitivity and specificity of 71.43% and 99.44%, respectively. The sensitivity and specificity of PCR (80.95% and 97.21%) did not exceed that of culture. CONCLUSION: With regard to the fact that trichomoniasis can have an atypical or even asymptomatic course, in order to accurately diagnose this disease, microbiological investigation is necessary. Comparison of different methods showed that at least two techniques, such as culture and acridine orange staining, have the potential for better diagnosis of T. vaginalis infection. PCR detection of infection has been demonstrated to be highly specific and sensitive, but its availability and cost effectiveness are in question. PCR could provide an alternative for laboratory diagnosis of trichomoniasis by culture.

[IgG serum antibody responses in suspected liver cystic echinococcosis patients].

INTRODUCTION: Cystic echinococcosis is a parasitic zoonosis caused by a tapeworm Echinococcus granulosus. Liver infection is the most common form of human echinococcosis. Diagnosis of liver echinococcosis could be made by different methods. It is very important to have good anamnesis and epidemiological evaluation, clinical status and clinical investigations such as X-ray examination, ultrasonography, nuclear magnetic resonance, computerized tomography, laboratory analysis and serology. Different serologic tests could be used for diagnosis of echinococcosis: complement fixation test, immunoelectrophoresis, indirect haemagglutination, latex agglutination, indirect fluorescence test and enzyme immunoassays sush as ELISA test. OBJECTIVE: The aim of this study was to investigate anti-E granulosus antibodies by ELISA test as a complementary laboratory method in the diagnosis of human echinococcosis. METHOD: In this study, we investigated 212 patients of suspected liver cystic echinococcosis. ELISA test was used for detection of whole anti-E granulosus IgG antibodies specific for AgB. RESULTS: Out of 212 patients, in 26 (12.26%) patients echinococcosis was confirmed by ELISA test. In 7/26 patients who had data about the ultrasonographic morphological type of cyst according to Gharbi, high values of seropositivity were found. Borderline values were found in 15/212 (7.08%) patients. In three patients with borderline values, second sera samples were examined after 18-22 days. In one patient, the test showed the same value, in the second patient echinococcosis was confirmed while in the third, the test showed a negative value. In 171 (80.66%) patients, anti-Echinococcus antibodies were not found by ELISA test. CONCLUSION: It has already been known that serological investigation has some limitations, but detection of specific antibodies remains an indispensable mark in evaluation of suspected liver cystic echinococcosis patients.

[Antifungal drug resistance: mechanisms of resistance, freqeuncy, prevention and control of resistance].

Fungi are important causes of human infections, especially systemic mycoses. Pathogenic fungi have many complex mechanisms of resistance to antifungal drugs. In this article, information about the cellular, genetic and clinical factors contributing to antifungal-drug resistance, and their diagnostic and epidemiologic characteristics are reviewed. Understanding the mechanisms of resistance should assist in developing better detection and preventive strategies. The emergence of acquired antifungal resistance, especially in immunocompromised hosts, has necessitated routine antifungal susceptibility testing. Initial antifungal screening of clinical isolates by the disk-diffusion method would be followed by confirmation of resistant strains by the broth dilution method. Also, strategies to avoid and suppress the antifungal resistance are discussed. There are several strategies to overcome antifungal resistance, including increased antifungal-dose intensity, immunomodulation, combined antifungal therapy and new antifungals.