Clostridium difficile Infection Diagnosis by Biological Molecular Methods

In the past 15 years, the incidence of Clostridium difficile infection has emerged especially because of the new highly virulent strains. The classical diagnosis methods used to diagnose C. difficile infection take time and the enzyme immunoassay (EIA) test has demonstrated the lack of sensitivity. Even though new modern molecular methods have become available, the diagnosis of C. difficile in patients or healthy carriers remains a big challenge for both clinicians and laboratory staff. In the present chapter, we will list the main genotyping methods, stressing their advantages and disadvantages, as well. A brief presentation of the most useful kit (principle, sensitivity, specificity, benefits and disadvantages) to assess the impact of molecular methods in comparison with classical methods will offer support for future research in the present context of an increasing prevalence of C. difficile infection that represents worldwide, a real public health problem. To improve the patients’ quality of life, to limit hospital transmission, and to save money, we have tried to identify the best diagnosis algorithm as tool in C. difficile diagnosis and surveillance. This algorithm may differ depending on the capacities of the laboratories and on the socioeconomic level of the countries in question

Merkel Cell Polyoma Virus and Cutaneous Human Papillomavirus Types in Skin Cancers: Optimal Detection Assays, Pathogenic Mechanisms, and Therapeutic Vaccination

Oncogenic viruses are recognized to be involved in some cancers, based on very well-established criteria of carcinogenicity. For cervical cancer and liver cancer, the responsible viruses are well-known (e.g., HPV, HBV); in the case of skin cancer, there are still many studies which are trying to identify the possible viral etiologic agents as principal co-factors in the oncogenic process. We analysed scientific literature published in the last 5 years regarding mechanisms of carcinogenicity, methods of detection, available targeted therapy, and vaccination for Merkel cell polyomavirus, and beta human papillomavirus types, in relation to skin cancer. This review is targeted at presenting the recent findings which support the involvement of these viruses in the development of some types of skin cancers. In order to optimize the management of skin cancer, a health condition of very high importance, it would be ideal that the screening of skin cancer for these two analysed viruses (MCPyV and beta HPV types) to be implemented in each region’s/country’s cancer centres’ molecular detection diagnostic platforms, with multiplex viral capability, optimal sensitivity, and specificity; clinically validated, and if possible, at acceptable costs. For confirmatory diagnosis of skin cancer, another method should be used, with a different principle, such as immunohistochemistry, with specific antibodies for each virus

Host mRNA Analysis of Periodontal Disease Patients Positive for Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Tannerella forsythia

Periodontal disease is a frequent pathology worldwide, with a constantly increasing prevalence. For the optimal management of periodontal disease, there is a need to take advantage of actual technology to understand the bacterial etiology correlated with the pathogenic mechanisms, risk factors and treatment protocols. We analyzed the scientific literature published in the last 5 years regarding the recent applications of mRNA analysis in periodontal disease for the main known bacterial species considered to be the etiological agents: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Tannerella forsythia. We identified new pathogenic mechanisms, therapeutic target genes and possible pathways to prevent periodontal disease. The mRNA analysis, as well as the important technological progress in recent years, supports its implementation in the routine management of periodontal disease patients

Heterogeneous Distribution of Fetal Microchimerism in Local Breast Cancer Environment.

Fetal cells enter maternal circulation during pregnancy and persist in the woman's body for decades, achieving a form of physiological microchimerism. These cells were also evidenced in tumors. We investigated the frequency and concentration of fetal microchimerism in the local breast cancer environment. From 19 patients with confirmed breast neoplasia, after breast surgical resection, we collected three fresh specimens from the tumor core, breast tissue at tumor periphery, and adjacent normal breast tissue. The presence of male DNA was analyzed with a quantitative PCR assay for the sex determining region gene (SRY) gene. In the group of women who had given birth to at least one son, we detected fetal microchimerism in 100% of samples from tumors and their periphery and in 64% (9 of 14) of those from normal breast tissue. The tissues from the tumor and its periphery carry a significantly increased number of SRY copies compared to its neighboring common breast tissue (p = 0.005). The median of the normalized SRY-signal was about 77 (range, 3.2-21467) and 14-fold (range, 1.3-2690) greater in the tumor and respectively in the periphery than in the normal breast tissue. In addition, the relative expression of the SRY gene had a median 5.5 times larger in the tumor than in its periphery (range, 1.1-389.4). We found a heterogeneous distribution of fetal microchimerism in breast cancer environment. In women with sons, breast neoplasia harbors male cells at significantly higher levels than in peripheral and normal breast tissue

HBV genotypes circulation in pregnant women in Romania: a pilot study

Background: The risk of mother to child transmission of hepatitis B virus (HBV) is recognized worldwide, a reason for which the World Health Organization aims to reduce this public health issue of major concern in the next ten years. The aim of our study was to detect circulating HBV genotypes in a selected population of pregnant women, as scientific evidence to recommend personalized antiviral therapy and to obtain updated epidemiological information

Staphylococcus lugdunensis endophthalmitis following dexamethasone intravitreal implant

We present a unique case of endophthalmitis with Staphylococcus lugdunensis following dexamethasone intravitreal implant for branch retinal vein occlusion associated with cystoid macular edema. Patient did not show favorable clinical response after vitrectomy and intravitreal antibiotics; so, we decided to repeat vitrectomy, remove the steroid implant and fill the eye with silicon oil, and repeat intravitreal vancomycin. Vision has improved from hand movements at presentation to counting fingers at 1.5 m after second vitrectomy and final visual acuity 3 months later after silicon oil removal was 6/36

The efficiency of sodC gene / N. meningitidis detection in comparison with the classical methods for the diagnosis of meningococcal infection / Evaluarea eficienţei Real Time PCR TaqMan utilizând gena sodC / N. meningitidis în comparaţie cu metodele clasice utilizate în diagnosticul infecţiei meningococice

Pentru a iniția corect terapia antibiotică și a institui profilaxia pentru contacți, infecția meningococică necesită un diagnostic cât mai rapid și precis. Scopul studiului nostru a fost evaluarea eficienței Real Time PCR -TaqMan utilizând gena sodC / N. meningitidis în comparație cu metodele clasice de diagnostic utilizate în infecția meningococică: examen direct, cultură, latex aglutinare din LCR (lichid cefalorahidian) și hemocultură. Prin RT-PCR au fost identificați 24/44 (54.54%) pacienți cu infecție meningococică; atât în cazul pacienților trataţi cu antibiotice anterior internării, cât și a celor fără tratament, cele mai înalte valori ale ariei de sub curbă au fost înregistrate în cazul RT-PCR din LCR și sânge. În concluzie, testul sodC RT-PCR este o metodă rapidă, cu sensibilitate și specificitate ridicate pentru detecția Neisseria meningitidis, motiv pentru care ar fi utilă includerea acestei metode ca variantă multiplex, pentru depistarea şi a altor etiologii, în testarea de rutină a pacienților cu suspiciune clinică de infecție meningococică

Detection of HPV 16 and HPV 18 viral loads by real time PCR in women with cervical dysplasia

Viral load of high risk HPV types 16 and 18 can be useful biomarkers in detecting women with cervical dysplasia in early stage, prior to development of cervical cancer. Purpose of the study was to assess the clinical utility of viral load determination for HPV 16 and 18 in relation with the severity of cervical dysplasia and the association of classical risk factors. The HPV 16 and 18 positive women were selected from a cohort study, using one HPV DNA test for screening. METHODS: Viral load quantification was performed with Real Time PCR MX3005P. RESULTS: The viral load for HPV 16 was between 3.45 - 7.177 x 106 copies / μl, and 1.138 x 103 to 7.119 x 104 for HPV 18. CONCLUSIONS: Viral load of high risk HPV types seems to be one sensitive and objective biological marker in detecting women at risk for developing cervical cancer. No significant association was fount for the risk factors investigated