Stamatina Levidiotou

An eternal microbe: Brucella DNA load persists for years after clinical cure.

BACKGROUND Despite the continuing high incidence of brucellosis, vague aspects of pathophysiology, diagnosis, and treatment continue to exist, particularly with regard to the ability of Brucella species to survive inside the host. METHODS A quantitative real-time polymerase chain reaction assay was used for monitoring bacterial DNA load in brucellosis-affected patients throughout different disease stages. Three or more specimens per patient were obtained (1 at diagnosis, 1 at the end of treatment, and at least 1 during the follow-up period) from 39 patients with acute brucellosis. RESULTS The majority of patients (87% at the end of treatment, 77% at 6 months after treatment completion, and 70% at >2 years after treatment) exhibited persistent detectable microbiological load despite being asymptomatic. The 3 patients who experienced relapse did not exhibit any statistically significant difference in their bacterial load at any stage of disease or during follow-up. CONCLUSION Brucella melitensis DNA persists despite appropriate treatment and apparent recovery. This finding offers a new insight into the pathophysiology of the disease: B. melitensis is a noneradicable, persisting pathogen.

Carriage of Neisseria meningitidis and Neisseria lactamica in northern Greece

In response to an increase in the number of cases of invasive meningococcal disease (IMD) in northern regions of Greece, a survey was carried out to determine if there was an increase in carriage of Neisseria meningitidis, particularly in areas where there have been increases in immigrant populations from neighbouring countries. The second objective was to determine if there was an increase in the serogroup C:2a:P1.5,2 a phenotype associated with recent outbreaks or changes in antibiotic sensitivities. As carriage of Neisseria lactamica is associated with development of natural immunity to IMD, the third objective was to determine the carriage rate of N. lactamica in this population. Among 3167 individuals tested, meningococci were isolated from 334 (10.5%). Compared with our previous studies, the proportion of meningococcal carriers was significantly increased among children in secondary education (11.3%) (chi2=9.67, P<0.005) and military recruits (37.4%) (chi2=21.11, P<0.000). Only 5/334 (1.5%) isolates expressed the phenotype associated with the increase in IMD in Greece. N. lactamica was isolated from 146/3167 (4.6%) participants. It was isolated from 71/987 (7.2%) children attending primary or nursery schools; however, the highest proportion of carriers (11.3%) was found in the boarding school for young Albanian men. In the 21-59-year age range, the majority of N. lactamica isolates (22/25, 88%) were from women, probably due to closer or more prolonged contact with children in the primary school age range. Smoking was significantly associated with isolation of meningococci from men but not from women. Penicillin-insensitive strains (25/334, 7.5%) were identified in all four regions examined; the majority (14/25, 56%) were obtained from military personnel. We conclude that there was a higher proportion of carriers in the population of northern Greece; however, the increase in carriage rate was not associated with the influx of immigrants from neighbouring countries, and there was not a higher incidence of the C:2a:P1.5,2 strain responsible for increased disease activity in Greece in either the immigrant or local populations.

Usefulness of Herpes Consensus PCR methodology to routine diagnostic testing for herpesviruses infections in clinical specimens.

The purposes of the study were to assess the usefulness of simultaneously amplifying herpes simplex virus 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus and human herpesvirus 6 DNA in various clinical specimens and to analyze clinical events in patients presenting positive results. A total of 763 clinical samples obtained from 758 patients, including 115 cerebrospinal fluids, 102 aqueous fluids, 445 swabs from genital (152), oro-facial (138) and other (155) skin lesions, 96 eye swabs and 5 bronchoalveolar lavages, were tested by using the Consensus polymerase chain reaction methodology. The clinical files of the patients were consulted retrospectively. 171 of the 758 patients (22.5%) were positive for at least one of the six target viruses: herpes simplex virus 1 (n = 95), varicella-zoster virus (n = 40), herpes simplex virus 2 (n = 21), herpes simplex virus 1 plus herpes simplex virus 2 (n = 8), cytomegalovirus (n = 4), Epstein-Barr virus (n = 1), human herpesvirus 6 (n = 1), and herpes simplex virus 1 plus human herpesvirus 6 (n = 1). The Consensus methodology enabled the rapid and accurate detection of herpesviruses in various clinical specimens and provided a reliable tool in the diagnosis of herpetic infections.

Utility of Real-Time PCR in the Diagnosis of Primary Epstein-Barr VirusInfection

Background: Despite the availability of several serological markers, Epstein-Barr virus (EBV) status of some patients is not easily resolved. Objectives: The aim of the present study was to investigate the quantification and the diagnostic utility of EBV DNA detection as an adjunct to serological diagnosis of primary EBV infection. Study Design: Sera from 118 patients referred for suspected primary EBV infection, were tested for heterophile antibodies (HA), IgM antibodies against viral capsid antigen (VCA IgM) and IgG against nuclear antigen (EBNA IgG). A quantitative real time EBV PCR assay (Light Cycler EBV Quant kit) was simultaneously performed in plasma of these patients. Results: EBV DNA was detected in 43 of 46 patients (93.5%) with serologically confirmed primary infection. By performing real time RCR in the remaining 72 samples, 24 additional cases were diagnosed: in 20 of them, VCA IgM was positive but not HA; in 4 cases, HA were positive, but not VCA IgM. EBV DNA load was detectable in all samples drawn until day 12 after onset of symptoms; 20 days after onset all samples were negative. Higher viral load levels were detected in younger patients and in male patients. Conclusions: The use of EBV PCR assay resulted in an increase in definitive diagnosis of primary EBV infection, enhancing overall diagnostic efficacy by 20.3%. Real time PCR is a reliable tool for diagnosis of primary EBV infection early in the course of disease and may especially serve as a useful diagnostic supplement in serologically unclear cases of EBV infection.

Point-prevalence survey of healthcare facility-onset healthcare-associated Clostridium difficile infection in Greek hospitals outside the intensive care unit: The C. DEFINE study

Background The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013. Methods There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea. Results 5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18–6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03–12.76, p = 0.045) were independent risk factors for CDI development. Charlson’s Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98–5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009). Conclusions The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.

The influence of postoperative infection in survival of patients with high-grade gliomas

High-grade gliomas are the most common type of brain tumors. Of these, glioblastoma account for 60-70% and despite treatment carries a dismal prognosis. Postoperative surgical site infection has been associated with prolonged survival. Herewith, we present a case of glioblastoma and a case of anaplastic oligoastrocytoma that developed postoperative infection of the surgical site and had prolonged survival. A thorough literature review is also presented.

Serum IgE levels in patients with intracranial tumors

Aim: Several epidemiological studies have shown an inverse correlation between allergy and brain cancer. The purpose of this study was to compare the serum IgE levels between patients with gliomas and nonglial tumors and their possible prognostic role. Methods: A total of 84 patients with intracranial tumors were included in this study. At clinical presentation, estimation of serum IgE levels was assessed by nephelometry. Detailed information regarding the history of allergies was collected by interview. Results: Of the 84 cases, 42 were gliomas, 23 were meningiomas, 16 were metastases and 3 were primary central nervous system lymphomas. Patients with high-grade glioma had lower IgE levels than patients with low-grade glioma. Patients with glioma and meningioma had statistical significant lower serum IgE levels than patients with metastases. Patients with glioblastoma with serum IgE levels greater than 24 U/mL had a better survival. Conclusion: Patients with glioma and meningioma had lower IgE levels than patients with metastatic lesions. A prognostic role of serum IgE levels was found in glioblastoma. Further studies in larger patient series are required in order to verify our preliminary observations.