Tuberculosis in sheltered homeless population of Rome: an integrated model of recruitment for risk management.

The authors show the results of an integrated model for risk management of tuberculosis in a sample of sheltered homeless in Rome. Tuberculin skin test (TST) was used for evaluating the prevalence of latent infection (LTBI). In TST positives, expectorate was collected and chest X-ray was achieved. Multiple logistic regression analysis was performed to investigate determinants of infection. Out of 288 recruited subjects, 259 returned for the TST reading; 45.56% were positive and referred to a specialized center; 70 accessed the health facility and completed the clinical pathway. The risk factors associated to LTBI were male gender (OR = 3.72), age over 60 years (OR = 3.59), immigrant status (OR = 3.73), and obesity (OR = 2.19). This approach, based on an integrated social network, guarantees high adherence to screening (89.93%), allowing patients testing positive for latent tuberculosis infection to be diagnosed and rapidly referred to a specialized center.

Detection of Pulmonary tuberculosis: comparing MR imaging with HRCT.

BACKGROUND: Computer Tomography (CT) is considered the gold standard for assessing the morphological changes of lung parenchyma. Although novel CT techniques have substantially decreased the radiation dose, radiation exposure is still high. Magnetic Resonance Imaging (MRI) has been established as a radiation- free alternative to CT for several lung diseases, but its role in infectious diseases still needs to be explored further. Therefore, the purpose of our study was to compare MRI with high resolution CT (HRCT) for assessing pulmonary tuberculosis. METHODS: 50 patients with culture-proven pulmonary tuberculosis underwent chest HRCT as the standard of reference and were evaluated by MRI within 24 h after HRCT. Altogether we performed 60 CT and MRI examinations, because 10 patients were also examined by CT and MRI at follow- up. Pulmonary abnormalities, their characteristics, location and distribution were analyzed by two readers who were blinded to the HRCT results. RESULTS: Artifacts did not interfere with the diagnostic value of MRI. Both HRCT and MRI correctly diagnosed pulmonary tuberculosis and identified pulmonary abnormalities in all patients. There were no significant differences between the two techniques in terms of identifying the location and distribution of the lung lesions, though the higher resolution of MRI did allow for better identification of parenchymal dishomogeneity, caseosis, and pleural or nodal involvement. CONCLUSION: Technical developments and the refinement of pulse sequences have improved the quality and speed of MRI. Our data indicate that in terms of identifying lung lesions in non-AIDS patients with non- miliary pulmonary tuberculosis, MRI achieves diagnostic performances comparable to those obtained by HRCT but with better and more rapid identification of pulmonary tissue abnormalities due to the excellent contrast resolution.

Duration of viral shedding in hospitalized patients infected with pandemic H1N1.

BACKGROUND: The first influenza pandemic of the 21th century was ignited by a new strain of influenza A virus (A/H1N1pdm). Specific patient groups, including those with comorbidities, pregnant women, young children, older and immunocompromised patients, are at increased risk for serious influenza-related disease. This study was aimed at investigating the influence of clinical presentation, antiviral treatment and possible drug resistance-associated mutations, on the extent and duration of viral shedding in patients infected with A/H1N1pdm. METHODS: An observational study was performed, based on retrospective review of clinical and laboratory records of patients who were hospitalized for A/H1N1pdm infection at the National Institute for Infectious Diseases "L. Spallanzani", Rome, Italy, between April 24 and December 31, 2009. Among 119 hospitalized patients, 39 were selected for a post hoc analysis, based on the availability of serial nasopharyngeal swabs samples and related information. RESULTS: Eleven out of the 39 study patients (28.2%) presented with pneumonia; 29 (74.4%) received antiviral treatment. Patients with pneumonia were significantly older than patients without pneumonia. The mean values of viral RNA concentration were not significantly increased in patients with pneumonia, but a significant increase in the duration of viral shedding was observed as compared to patients without pneumonia. In patients receiving antivirals, the viral RNA concentration was significantly reduced in comparison to untreated patients at days 4-5 after symptom onset, while the overall duration of viral shedding was only marginally affected. A significant correlation between duration of viral shedding and time elapsed between symptom onset and therapy start was observed, with a significant reduction of days of viral shedding when therapy was initiated within 2 days of symptoms appearance. No known drug resistance mutations were detected in patients with prolonged viral shedding. CONCLUSIONS: Our results show that severe respiratory illness is associated with delayed virus clearance in patients with A/H1N1pdm infection. Antivirals caused an early reduction of viral load, but only marginally affected the overall duration of shedding. Prolonged shedding was not associated with the emergence of strains carrying known drug-resistance mutations.

IP-10 detection in urine is associated with lung diseases.

BACKGROUND: Blood cytokines and chemokines have been proposed as biomarkers for tuberculosis (TB). Recently, some immune mediators found in the urine of patients with renal dysfunctions have also been suggested as potential biomarkers. Finding biomarkers for TB in urine would present several advantages over blood in terms of collection and safety. The objective of this study was to investigate the presence of cytokines and chemokines in the urine of patients with pulmonary TB at the time of diagnosis. In a subgroup, the evaluation was also performed during TB treatment and at therapy completion. Patients with lung diseases other than TB, and healthy subjects were also enrolled. METHODS: Urine samples from 138 individuals, after exclusion of renal dysfunctions, were collected during an 18 month-period. Among them, 58 received a diagnosis of pulmonary TB, 28 resulted having lung diseases other than TB, and 34 were healthy subjects. Moreover, 18 TB patients, 9 of whom were tested 2 months after AFB smear sputum reversion and 9 of whom were cured of TB were also included. Cytokines and chemokines in urine were evaluated using a Cytometric-Bead-Array-Flex-Set. IP-10 detection in 49 subjects was also carried out in parallel by using an Enzyme Linked ImmunoSorbent Assay (ELISA). RESULTS: IFN-γ, TNF-α, IL-2, IL-8, MIP-1α, MIP-1ß and RANTES were poorly detected in all urine samples. Conversely, IP-10 was consistently detected in urine and its level was significantly increased in patients with lung disease compared to healthy subjects (p < 0.001). Increased IP-10 levels were found in both pulmonary TB and lung diseases other than TB. Moreover lower IP-10 levels were found in cured-TB patients compared to the levels at the time of diagnosis, and this difference was close to significance (p = 0.06). Interestingly, we demonstrated a significant correlation between the data obtained by flow cytometry and ELISA (r² 0.82, p < 0.0001). CONCLUSIONS: IP-10, in contrast to IFN-γ, TNF-α, IL-2, IL-8, MIP-1α, MIP-1ß and RANTES, is detectable in the urine of patients with pulmonary diseases in the absence of renal dysfunctions. Moreover, the IP-10 level in cured-TB patients is comparable to that found in healthy subjects. More studies are needed to further investigate the clinical utility of these findings.

Resistant and multi-resistant Gram-positive severe infections: the GISIG working methodology.

BACKGROUND: Five thematic working groups composed of Italian infectious disease experts and a group coordinator, supported by a scientific secretary, identified controversial issues in the field of severe healthcare-associated infections caused by multidrug-resistant organisms. The five group coordinators received training courses on data sources and electronic databases, literature search strategies, the scientific revision methods of quality assessment, and the construction of an evidence matrix. WORKING PLAN AND METHODS: The working plan identified the following step: definition of the controversial issues and identification of documents for a systematic literature review. A specific methodology to classify the selected evidence was used that required the evaluation of the quality of review documents and statement documents and evaluation of the quality of original research. An original method to assess review documents and statement documents was proposed. A matrix model to extract and evaluate the evidence from original studies was designed using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, cohorts, and retrospective studies. QUALITY OF EVIDENCE: A modified GRADE working group method was applied for grading quality of evidence and strength of recommendations. The working groups reviewed the available studies and formulated recommendations to be voted on at the national consensus conference held in Rome in June 2009.

Consensus document on controversial issues in the diagnosis and treatment of prosthetic joint infections.

BACKGROUND: Joint replacement surgery has been on the increase in recent decades and prosthesis infection remains the most critical complication. Many aspects of the primary prevention and clinical management of such prosthesis infections still need to be clarified. CONTROVERSIAL ISSUES: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for the following controversial issues: (1) Is a conservative surgical approach for the management of prosthetic joint infections effective? (2) Is the one-stage or the two-stage revision for the management of prosthetic joint infections more effective? (3) What is the most effective treatment for the management of prosthetic joint infections due to methicillin-resistant staphylococci? Results are presented and discussed in detail. METHODS: A systematic literature search using the MEDLINE database for the period 1988 to 2008 of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence and strength of recommendation was applied.

Consensus document on controversial issues in the diagnosis and treatment of bloodstream infections and endocarditis.

BACKGROUND: The treatment of severe bloodstream infections (sepsis, endocarditis, and infections of vascular prostheses) caused by Gram-positive microorganisms is made even more difficult by the emergence of resistant strains. The introduction of new antibiotics with activity against these strains has created new opportunities, but many controversial issues remain. CONTROVERSIAL ISSUES: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues concerned the duration of therapy and role of aminoglycosides and teicoplanin in the treatment of Gram-positive bacterial endocarditis, the optimal use of the new antibiotics in the treatment of bloodstream infections caused by resistant Gram-positive strains, and the use of microbiological techniques (i.e., bactericidal serum testing and synergy testing) and of pharmacokinetic data (e.g., monitoring of plasma levels of antibiotics) in the treatment of difficult-to-treat Gram-positive bloodstream infections. METHODS: A systematic literature search of randomized controlled trials and/or non-randomized studies was performed mainly using the MEDLINE database. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for non-randomized studies. The GRADE method for grading the quality of evidence and strength of recommendation was applied.

Consensus document on controversial issues for the treatment of infections of the central nervous system: bacterial brain abscesses.

BACKGROUND: Bacterial brain abscesses remain a serious central nervous system problem despite advances in neurosurgical, neuroimaging, and microbiological techniques and the availability of new antibiotics. The successful treatment of brain abscesses requires surgery, appropriate antibiotic therapy, and eradication of the primary source; nevertheless many controversial issues on the management of this serious infection remain unresolved. CONTROVERSIAL ISSUES: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues were: (1) Which patients with bacterial brain abscesses can be managed safely using medical treatment alone? (1a) What is the efficacy in terms of outcome, tolerability, cost/efficacy, and quality of life of the different antibiotic regimens used to treat bacterial cerebral abscesses? (1b) Which antibiotics have the best pharmacokinetics and/or tissue penetration of brain and/or brain abscess? 2) What is the best surgical approach in terms of outcome in managing bacterial brain abscesses? Results are presented and discussed in detail. METHODS: A systematic literature search using the MEDLINE database for the period 1988 to 2008 of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence and strength of recommendation was applied.

Methicillin-resistant Staphylococcus aureus: the superbug.

Over the last decade, methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged as serious pathogens in the nosocomial and community setting. Hospitalization costs associated with MRSA infections are substantially greater than those associated with methicillin-sensitive S. aureus (MSSA) infections, and MRSA has wider economic effects that involve indirect costs to the patient and to society. In addition, there is some evidence suggesting that MRSA infections increase morbidity and the risk of mortality. Glycopeptides are the backbone antibiotics for the treatment of MRSA infections. However, several recent reports have highlighted the limitations of vancomycin, and its role in the management of serious infections is now being reconsidered. Several new antimicrobials demonstrate in vitro activity against MRSA and other Gram-positive bacteria. Data from large surveys indicate that linezolid, daptomycin, and tigecycline are almost universally active against MRSA. This review will briefly discuss the epidemiology, costs, outcome, and therapeutic options for the management of MRSA infections.

Consensus document on controversial issues in the treatment of complicated skin and skin-structure infections.

BACKGROUND: Complicated skin and skin-structure infections (cSSSI), including surgical site infections (SSI), cellulitis, and abscesses, have been extensively studied, but controversial issues still exist. CONTROVERSIAL ISSUES: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for the following controversial issues: (1) What is the efficacy of topical negative pressure wound treatment as compared to standard of care in the treatment of severe surgical site infections, i.e., deep infections, caused by Gram-positive microorganisms? (2) Which are the most effective antibiotic therapies in the treatment of cSSSI, including SSI, due to methicillin-resistant staphylococci? Results are presented and discussed. METHODS: A systematic literature search using the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and www.clinicaltrials.gov databases of randomized controlled trials and/or non-randomized studies was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method was used for grading quality of evidence. An analysis of the studies published between 1990 and 2008 is presented and discussed in detail.

Consensus document on controversial issues for the treatment of hospital-associated pneumonia.

BACKGROUND: Hospital-associated pneumonia (HAP) remains an important cause of morbidity and mortality despite advances in antimicrobial therapy. Many aspects of the treatment of HAP caused by multi-resistant Gram-positive microorganisms have been extensively studied, but controversial issues remain. CONTROVERSIAL ISSUES: The aim of this GISIG (Gruppo Italiano di Studio sulle Infezioni Gravi) working group - a panel of multidisciplinary experts - was to define recommendations for some controversial issues using an evidence-based and analytical approach. The controversial issues were: (1) Is combination antibiotic therapy or monotherapy more effective in the treatment of HAP? (2) What role do pharmacokinetic/pharmacodynamic antibiotic features have as a guide in the selection of treatment for HAP? (3) Is a de-escalation approach for the management of HAP effective? An analysis of the studies published up until April 2009 is presented and discussed in detail. METHODS: A systematic literature search using PubMed, MEDLINE, and EMBASE databases and the Cochrane Library was performed. A matrix was created to extract evidence from original studies using the CONSORT method to evaluate randomized clinical trials and the Newcastle-Ottawa Quality Assessment Scale for case-control studies, longitudinal cohorts, and retrospective studies. The GRADE method for grading quality of evidence was applied.

A case of pulmonary tuberculosis presenting as diffuse alveolar haemorrhage: is there a role for anticardiolipin antibodies?

BACKGROUND: Diffuse alveolar haemorrhage (DAH) has been rarely reported in association with pulmonary infections. CASE PRESENTATION: We report the case of a 43 year old immunocompetent man presenting with dyspnoea, fever and haemoptysis. Chest imaging showed bilateral ground glass opacities. Microbiological and molecular tests were positive for Mycobacterium tuberculosis and treatment with isoniazid, rifampicin, ethambutol and pyrazinamide was successful. In this case the diagnosis of DAH relies on clinical, radiological and endoscopic findings. Routine blood tests documented the presence of anticardiolipin antibodies. In the reported case the diagnostic criteria of antiphospholipid syndrome were not fulfilled. CONCLUSIONS: The transient presence of anticardiolipin antibodies in association with an unusual clinical presentation of pulmonary tuberculosis is intriguing although a causal relationship cannot be established.

New tools for detecting latent tuberculosis infection: evaluation of RD1-specific long-term response.

BACKGROUND: Interferon-gamma (IFN-gamma) release assays (IGRAs) were designed to detect latent tuberculosis infection (LTBI). However, discrepancies were found between the tuberculin skin test (TST) and IGRAs results that cannot be attributed to prior Bacille Calmètte Guerin vaccinations. The aim of this study was to evaluate tools for improving LTBI diagnosis by analyzing the IFN-gamma response to RD1 proteins in prolonged (long-term response) whole blood tests in those subjects resulting negative to assays such as QuantiFERON-TB Gold In tube (QFT-IT). METHODS: The study population included 106 healthy TST+ individuals with suspected LTBI (recent contact of smear-positive TB and homeless) consecutively enrolled. As controls, 13 healthy subjects unexposed to M. tuberculosis (TST-, QFT-IT-) and 29 subjects with cured pulmonary TB were enrolled. IFN-gamma whole blood response to RD1 proteins and QFT-IT were evaluated at day 1 post-culture. A prolonged test evaluating long-term IFN-gamma response (7-day) to RD1 proteins in diluted whole blood was performed. RESULTS: Among the enrolled TST+ subjects with suspected LTBI, 70/106 (66.0%) responded to QFT-IT and 64/106 (60.3%) to RD1 proteins at day 1. To evaluate whether a prolonged test could improve the detection of LTBI, we set up the test using cured TB patients (with a microbiologically diagnosed past pulmonary disease) who resulted QFT-IT-negative and healthy controls as comparator groups. Using this assay, a statistically significant difference was found between IFN-gamma levels in cured TB patients compared to healthy controls (p < 0.006). Based on these data, we constructed a receiver operating characteristic (ROC) curve and we calculated a cut-off. Based on the cut-off value, we found that among the 36 enrolled TST+ subjects with suspected LTBI not responding to QFT-IT, a long term response to RD1 proteins was detected in 11 subjects (30.6%). CONCLUSION: These results indicate that IFN-gamma long-term response to M. tuberculosis RD1 antigens may be used to detect past infection with M. tuberculosis and may help to identify additional individuals with LTBI who resulted negative in the short-term tests. These data may provide useful information for improving immunodiagnostic tests for tuberculosis infection, especially in individuals at high risk for active TB.

Patient to patient transmission of hepatitis B virus: a systematic review of reports on outbreaks between 1992 and 2007.

BACKGROUND: Hepatitis B outbreaks in healthcare settings are still a serious public health concern in high-income countries. To elucidate the most frequent infection pathways and clinical settings involved, we performed a systematic review of hepatitis B virus outbreaks published between 1992 and 2007 within the EU and USA. METHODS: The research was performed using two different databases: the PubMed Database and the Outbreak Database, the worldwide database for nosocomial outbreaks. Selection of papers was carried out using the Quorom algorithm, and to avoid selection biases, the inclusion criteria were established before the articles were identified. RESULTS: Overall, 30 papers were analyzed, reporting on 33 hepatitis B virus outbreaks that involved 471 patients, with 16 fatal cases. Dialysis units accounted for 30.3% of outbreaks followed by medical wards (21.2%), nursing homes (21.2%), surgery wards (15.2), and outpatient clinics (12.1%). The transmission pathways were: multi-vial drugs (30.3%), non-disposable multi-patient capillary blood sampling devices (27.2%), transvenous endomyocardial biopsy procedures (9.1%), and multiple deficiencies in applying standard precautions (9.1%). CONCLUSION: The analysis of transmission pathways showed that some breaches in infection control measures, such as administration of drugs using multi-vial compounds and capillary blood sampling, are the most frequent routes for patient-to-patient transmission of hepatitis B virus. Moreover some outbreak reports underlined that heart-transplant recipients are at risk of contracting hepatitis B virus infection during the transvenous endomyocardial biopsy procedure through indirect contact with infected blood as a result of environmental contamination. To prevent transmission, healthcare workers must adhere to standard precautions and follow fundamental infection control principles, such as the use of sterile, single-use, disposable needles and avoiding the use of multi-vial compounds in all healthcare settings including outpatient settings.

Improved detection of human influenza A and B viruses in respiratory tract specimens by hemi-nested PCR.

RT-PCR is the most sensitive assay for diagnosis of influenza, due to enhanced rapidity and sensitivity as compared to classical methods. Hemi-nested RT-PCR was developed, targeting NP gene for influenza A and NS gene for influenza B, based on a previous single round RT-PCR method. The new method was compared with the previous technique for analytical sensitivity and specificity, and was applied to clinical samples from the lower and upper respiratory tract. The analytical sensitivity of hemi-nested RT-PCR was 10 (influenza A) and 4 times (influenza B) higher than the previous method. A high specificity of the new hemi-nested RT-PCR assay was observed by using whole respiratory viruses. When applied to lower respiratory tract specimens, the new method showed an increased rate of positivity as compared to the previous technique (9.3% versus 0.7% for influenza A, and 0.9% versus 0.2% for influenza B). Screening of upper respiratory tract samples collected during the seasonal 2005-2006 outbreak indicated 26.4% and 5.8% positivity for influenza A and B, respectively. The results were confirmed by sequence analysis: apart from influenza B, both influenza A subtypes H3N2 and H1N1, associated with the seasonal outbreak, were detected.