Melania Ruggeri

Interferon‐γ release assay in people infected with immunodeficiency virus

The present study aimed to use QuantiFERON TB Gold in tube (Cellestis Limited, Carnegie, Victoria, Australia) as a tool for the screening for tubercular infection in HIV-positive patients. Seventy-three HIV-positive subjects were tested. For each individual, QuantiFERON TB in tube was performed. The immunoassay was negative in 53 subjects, positive in eight and indeterminate in 12. The data obtained indicate that factors such as the CD4 cell count and their percentage, as well as the stage of the disease, could affect the performance of the interferon-γ release assay in populations at risk such as HIV-positive subjects.

Could inducible protein-10 and heparin-binding hemagglutinin improve the detection of Mycobacterium tuberculosis-infected subjects in a country with low incidence of tuberculosis ?

Abstract Background: This study aimed to evaluate inducible protein-10 (IP-10) as a biomarker besides interferon-gamma (IFN-γ) to improve the identification of active tuberculosis (TB) and latent tubercular infection (LTBI) in a country with a low incidence of TB. Methods: Whole blood from Mycobacterium tuberculosis-infected subjects was stimulated with region-of-difference-1 (RD1)-specific peptides and with heparin-binding hemagglutinin (HBHA) to determine the release of IP-10 and IFN-γ. Results: No statistically significant difference was observed between positive rates of IP-10 and IFN-γ after RD1-specific peptide stimulation in the TB and LTBI groups; a different response was detected in QuantiFERON TB-gold test-negative (QFT–) subjects. A significantly different proportion of positive responses was observed between IP-10 and IFN-γ following HBHA stimulation in the TB group and in the QFT– group but not in the LTBI group. Conclusions: The IP-10 test seemed to identify false-negative QFT results in some subjects with a positive IFN-γ/IP-10/HBHA pattern.

Beyond pulmonary nontuberculous mycobacteria disease: do extra-pulmonary forms represent an emerging clinical and public health threat?

Nontuberculous mycobacteria (NTM) are a heterogeneous group of pathogens including all mycobacteria other than Mycobacterium tuberculosis complex and Mycobacterium leprae [1]. The rate of NTM infection has increased substantially over the last decades, especially in high-income countries, as recently illustrated by Diel et al. [2] who have highlighted the relevant clinical and economic burden of NTM disease in Germany. The main reasons include the aging of the population, the increasing number of patients with immunodepressive disorders, the use of immunosuppressive agents and a substantial increase in awareness of the disease [3]. Epidemiological data on NTM worldwide are lacking and very few reports have been published based on the Italian population [4, 5]. Pulmonary and extra-pulmonary diseases caused by nontuberculous mycobacteria: new clinical and public health threats http://ow.ly/87Dm30eMFd9

Tuberculosis in Sardinia: An investigation into the relationship between natives and immigrants

Objective/background: Tuberculosis (TB) has had a recrudescence in the last few decades in Italy as a result of many factors, among which migration from countries where TB is endemic is one of them. In Sardinia, a major island of Italy, there was no knowledge of the mechanisms of transmission of TB in the immigrant subpopulation and the impact it may have on the native subpopulation and on the community as a whole. Therefore, a molecular epidemiological study was carried out to get a clearer picture of the number and genetic features of Mycobacterium tuberculosis strains isolated from immigrants and from natives in Sardinia. Methods: Two groups of clinical isolates of M. tuberculosis, one collected from immigrants and the other one from Sardinians, were analyzed in this study. The genotyping was executed through the variable number tandem repeat-mycobacterial interspersed repetitive units technique and a first-line antimycobacterial drug-susceptibility test was also carried out. Results: Thirty-six clinical isolates from immigrants and 25 from Sardinians were analyzed. Variable number tandem repeat-mycobacterial interspersed repetitive units technique showed that all of them belonged to different strains and there was a quite high allelic diversity among them. Moreover, data collected allowed the finding of, with a good approximation, the phylogenetic relations among the strains isolated and the best-known phylogenetic groups. Conclusion: The study pointed out that since every strain is different, there was no TB transmission in any of the subpopulations and between immigrants and natives. This showed that the presence of immigrants was not a risk factor for contracting TB in the community.

Epidemic of tuberculosis in a high school in Northern Sardinia

The aim of this study was to investigate the Mycobacterium tuberculosis transmission among high school student and teacher populations in a high school in Northern Sardinia. Tuberculin skin-test screening, chest-X-rays, QuantiFERON-TB Gold, microbiological examination, spoligotyping and variable numbers of tandem repeats (VNTR) analysis of M. tuberculosis isolates were performed. This study indicates the effectiveness of the epidemiological investigation.

USEFULNESS OF THE QUANTIFERON-TB-GOLD IN TUBE IN A POPULATION AT RISK OF BOVINE TUBERCULAR INFECTION

The effectiveness of the QuantiFERON-TB-Gold in tube was compared with PPD to detect tuberculosis infection in the staff of cattle-farms, as a consequence of an outbreak of bovine tuberculosis in livestock. The data revealed the advantage of the immunological test for the specific detection of subjects infected by Mycobacterium tuberculosis complex.