Epidemiology of Mycobacterium tuberculosis infection in Pavia province, Lombardy, Northern Italy, 1998-2013.

This study investigated the epidemiology of tuberculosis in the last 16 years in the province of Pavia, Lombardy, Northern Italy. The objective was to evaluate the clinical pattern of tuberculosis in immigrant groups compared with Italians in an observational retrospective study conducted from 1998 to 2013. In all, 615 tuberculosis cases were admitted, 354 males (57.3%), median age 47-years, 425 (69.1%) Italian-born patients, 190 (30.9%) immigrants. The ratio between the immigrant group and the Italian-born group of patients increased from 1.7% to 54.5% in the study period (p=0.001). HIV was the most common comorbidity, affecting 48 patients (7.8%), followed by diabetes in 35 (5.7%) and COPD in 30 (4.9%). The overall admission-associated mortality was 5.5%. Italian-born patients were older than non-Italian born subjects and had at least one comorbidity, 162 (38.1%) and 22 (11.6%), respectively (p<0,0001). Mortality was increased among Italian-born compared with non-Italian-born patients (7.3% versus 1.6%, p=0.004). No significant variation in extra-pulmonary tuberculosis (EPTB) prevalence occurred. Considering specific form of EPTB, HIV infection was associated with an increased risk of EPTB (RR 2.02, 95%CI 1.09-3.74, p=0.026). There was a high risk of tuberculosis among immigrants, whereas a decreasing trend was consistently observed among Italian-born patients. Italian-born patients show a higher tuberculosis-associated mortality risk due to older age and comorbidities.

Epidemiological characteristics of bloodstream infections in patients with different degrees of liver disease.

Observational retrospective study to evaluate the etiology, the outcome and the risk factors of bloodstream infections (BSIs) in patients with liver disease. One hundred and forty-eight BSIs were diagnosed (infection rate: 0.60 per 100 days of hospital stay), 62 BSIs (41.9 %) were associated with Gram-positive bacteria (infection rate: 0.25 per 100 days of hospital stay) and 80 (54.4 %) with Gram-negative bacteria (infection rate: 0.32 per 100 days of hospital stay). Admission-associated mortality was higher in patients with BSI than in those without BSI (20.6 versus 5.0 %, p < 0.001). Patients with cirrhosis had an increased risk to develop a BSI compared with patients with chronic hepatitis, specifically for Gram-positive (and Staphylococcus spp)-related BSI.

Post-exposure rate of tuberculosis infection among health care workers measured with tuberculin skin test conversion after unprotected exposure to patients with pulmonary tuberculosis: 6-year experience in an Italian teaching hospital.

BACKGROUND: This study assesses the risk of LTBI at our Hospital among HCWs who have been exposed to TB patients with a delayed diagnosis and respiratory protection measures were not implemented. METHODS: All HCWs exposed to a patient with cultural confirmed pulmonary TB and respiratory protection measures were not implemented were included. Data on TST results performed in the past (defined as T0) were recorded. TST was performed twice: first, immediately after exposure to an index patient (T1) and three months later (T2). The period of time between T0 and T1 was used to calculate he annual rate of tuberculosis infection (ARTI), while le period of time between T1 and T2 was used to calculate the post exposure annual rate of tuberculosis infection (PEARTI). RESULTS: Fourteen index patients were admitted; sputum smear was positive in 7 (58.3%), 4 (28.6%) were non-Italian born patients. 388 HCWs were exposed to index patients, a median of 27 (12-39) HCW per each index patient. One hundred eighty (46.4%) HCWs received BCG in the past. One hundred twenty two HCWs (31%) were TST positive at a previous routine screening and not evaluated in this subset. Among the remaining 255 HCWs with negative TST test in the past, TST at T1 was positive in 11 (4.3%). ARTI was 1.6 (95% CI 0.9-2.9) per 100 PY. TST at T2 was positive in 9 (3.7%) HCWs, that were TST negative at T1. PEARTI was 26 (95% CI 13.6-50) per 100 PY. At univariate analysis, older age was associated with post exposure latent tuberculosis infection (HR 1.12; 95% CI 1.03-1.22, p=0.01). CONCLUSIONS: PEARTI was considerably higher among HCWs exposed to index patients than ARTI. These data underscore the overwhelming importance of performing a rapid diagnosis, as well as implementing adequate respiratory protection measures when TB is suspected.

Staphylococcus aureus toxic shock syndrome toxin-1 endocarditis with muscular metastatic abscesses.

A 42-year-old woman, living in a nursing home for the mentally disabled, with congenital ventricular septal defect and multiple comorbidities, developed endocarditis with vegetations of the interventricular septum and the right coronary aortic leaflet. The main feature of this case was the metastatic embolism leading to multiple and muscular abscesses. Methicillin-sensitive S. aureus, spa type 253 and ST30, producing toxin shock syndrome toxin-1 was isolated from blood cultures. The patient was initially treated with beta-lactam antibiotics without showing clinical response and subsequently with daptomycin and linezolid that improved the patient's clinical symptoms. The effectiveness of treatment with daptomycin and linezolid was partly due to the ability of linezolid to reduce TSST-1 secretion. The portal of entry of the infection was not recognized. TSST-1 production by the strain might have favoured the formation of large cardiac vegetations and the subsequent metastatic dissemination to the muscles.

Detection of Epstein-Barr virus-specific memory CD4+ T cells using a peptide-based cultured enzyme-linked immunospot assay.

Approaches to evaluate T-cell responses to Epstein-Barr virus (EBV) include enzyme-linked immunospot (ELISPOT), which quantifies cells capable of immediate interferon-γ secretion upon antigen stimulation. However, evaluation of expandable EBV-specific memory T cells in an ELISPOT format has not been described previously. We quantified EBV-specific T-cell precursors with high proliferative capacity by using a peptide-based cultured interferon-γ ELISPOT assay. Standard and cultured ELISPOT responses to overlapping peptide pools (15-mers overlapping by 11 amino acids) covering the lytic (BZLF1 and BMRF1) and latent (EBNA1, EBNA3a, EBNA3b, EBNA3c, LMP1 and LMP2) EBV proteins were evaluated in 20 healthy subjects with remote EBV infection and, for comparison, in four solid organ transplant recipients. Cultured ELISPOT responses to both lytic and latent EBV antigens were significantly higher than standard ELISPOT responses. The distribution of EBV-specific T-cell responses detected in healthy virus carriers showed more consistent cultured ELISPOT responses compared with standard ELISPOT responses. T-cell responses quantified by cultured ELISPOT were mainly mediated by CD4+ T cells and a marked pattern of immunodominance to latent-phase antigens (EBNA1 > EBNA3 family antigens > LMP2 > LMP1) was shown. Both the magnitude and distribution of EBV-specific T-cell responses were altered in solid organ transplant recipients; in particular, cultured ELISPOT responses were almost undetectable in a lung-transplanted patient with EBV-associated diseases. Analysis of T-cell responses to EBV by ELISPOT assays might provide new insights into the pathogenesis of EBV-related diseases and serve as new tools in the monitoring of EBV infection in immunocompromised patients.

Postinfectious neurologic syndromes: a prospective cohort study.

OBJECTIVES: Postinfectious neurologic syndromes (PINSs) of the CNS include heterogeneous disorders, sometimes relapsing. In this study, we aimed to a) describe the spectrum of PINSs; b) define predictors of outcome in PINSs; and c) assess the clinical/paraclinical features that help differentiate PINSs from multiple sclerosis (MS). METHODS: In this prospective cohort study, adult inpatients with PINSs underwent extensive diagnostic assessment and therapeutic protocols at inclusion and during a minimum 2-year follow-up. We compared them with newly diagnosed, treatment-naive patients with MS, also prospectively recruited. RESULTS: The study sample comprised 176 patients with PINSs aged 59.9 ± 17.25 years (range: 18-80 years) divided into 2 groups: group 1 (CNS syndromes, 64%)-encephalitis, encephalomyelitis, or myelitis; and group 2 (CNS + peripheral nervous system [PNS] syndromes, 36%)-encephalomyeloradiculoneuritis or myeloradiculoneuritis. We observed the patients for 24 to 170 months (median 69 months). Relapses, almost invariably involving the spinal cord, occurred in 30.5%. PNS involvement was an independent risk factor for relapses (hazard ratio 2.8). The outcome was poor in 43% of patients; risk factors included older age, greater neurologic disability at onset, higher serum-CSF albumin percentage transfer, myelitis, and PNS involvement. Steroid resistance occurred in 30% of the patients, half of whom responded favorably to IV immunoglobulins. Compared with MS, PINSs were characterized by older age, lower tendency to relapse, and distinct CSF findings. CONCLUSIONS: The category of PINSs should be revised: most of the clinical variants have a poor prognosis and are not readily classifiable on the basis of current knowledge. PNS involvement has a critical role in relapses, which seem to affect the spine only.

Performance of liver stiffness measurements by transient elastography in chronic hepatitis.

AIM: To compare results of liver stiffness measurements by transient elastography (TE) obtained in our patients population with that used in a recently published meta-analysis. METHODS: This was a single center cross-sectional study. Consecutive patients with chronic viral hepatitis scheduled for liver biopsy at the outpatient ward of our Infectious Diseases Department were enrolled. TE was carried out by using FibroScan™ (Echosens, Paris, France). Liver biopsy was performed on the same day as TE, as day case procedure. Fibrosis was staged according to the Metavir scoring system. The diagnostic performance of TE was assessed by using receiver operating characteristic (ROC) curves and the area under the ROC curve analysis. RESULTS: Two hundred and fifty-two patients met the inclusion criteria. Six (2%) patients were excluded due to unreliable TE measurements. Thus, 246 (171 men and 75 women) patients were analyzed. One hundred and ninety-five (79.3%) patients had chronic hepatitis C, 41 (16.7%) had chronic hepatitis B, and 10 (4.0%) were coinfected with human immunodeficiency virus. ROC curve analysis identified optimal cut-off value of TE as high as 6.9 kPa for F ≥ 2; 7.9 kPa for F ≥ 3; 9.6 kPa for F = 4 in all patients (n = 246), and as high as 6.9 kPa for F ≥ 2; 7.3 kPa for F ≥ 3; 9.3 kPa for F = 4 in patients with hepatitis C (n = 195). Cut-off values of TE obtained by maximizing only the specificity were as high as 6.9 kPa for F ≥ 2; 9.6 kPa for F ≥ 3; 12.2 kPa for F = 4 in all patients (n = 246), and as high as 7.0 kPa for F ≥ 2; 9.3 kPa for F ≥ 3; 12.3 kPa for F = 4 in patients with hepatitis C (n = 195). CONCLUSION: The cut-off values of TE obtained in this single center study are comparable to that obtained in a recently published meta-analysis that included up to 40 studies.

Xenotropic and polytropic murine leukemia virus-related sequences are not detected in the majority of patients with chronic fatigue syndrome.

XMRV and polytropic MLV-related virus have been controversially associated with chronic fatigue syndrome (CFS). Subsequent reports failed to detect XMRV and MLV-related virus in CFS patients, and the previous results have been interpreted as a massive laboratory contamination by mouse DNA sequences. Among 12 sequential CFS patients, two were positive for XMRV/MLV sequences. In contrast, 40 selected control subjects were negative. CSF patients and controls were negative for mitochondrial mouse-specific DNA sequences. These findings do not confirm the high frequency of MLV-related viruses infection in CFS patients, but also contrast the widespread laboratory contamination previously suggested.

Guillain-Barré syndrome associated with the D222E variant of the 2009 pandemic influenza A (H1N1) virus: case report and review of the literature.

Guillain-Barré syndrome (GBS) is an acute immune-mediated disorder of the peripheral nervous system and a triggering infectious event is often reported in the weeks before the disease onset. Influenza viruses have been associated with Guillain-Barré syndrome (GBS), both after infection and, in rare cases, after vaccination. However, GBS has rarely reported to be a neurological complication of the recent pandemic influenza A(H1N1) 2009 virus infections. Here we describe the case of a young man, who developed acute severe motor inflammatory demyelinating polyradiculoneuropathy during influenza A(H1N1)2009 infection. Peculiar features are the findings of a mutated haemagglutinin gene (D222E variant), which has never previously been associated with neurological involvement, and the almost simultaneous appearance of respiratory infectious and immune-mediated neurological symptoms. Moreover we review the clinical presentation, laboratory findings and outcome of influenza-related GBS.

Kinetics of T-lymphocyte subsets and posttransplant opportunistic infections in heart and kidney transplant recipients.

BACKGROUND: The potential use of T-lymphocyte measurements as infection risk markers after solid organ transplant has not been fully investigated. We analyzed the kinetics of T-lymphocyte subsets within the first 8 months posttransplant and their correlation with opportunistic infections (OIs) in solid organ transplant recipients. METHODS: Serial measurement of CD4 and CD8 T cells was performed retrospectively in 48 heart transplant recipients (HTR) and 42 kidney transplant recipients (KTR). Generalized estimating equation models were used to analyze longitudinal data separately for HTR and KTR. RESULTS: An initial CD4 T-cell drop (at months 1 and 2, in HTR and KTR, respectively) coincided with the peak of OIs. HTR with a low nadir CD4 T-cell count (≤ 200/µL) showed poor CD4 T-cell recovery (175 ± 277 cells/µL at baseline vs 242 ± 99 cells/µL at month 8) and their CD8 T cells increased from 153 ± 194 cells/µL at baseline to 601 ± 399 cells/µL at month 8. KTR with a low nadir CD4 T-cell count (≤ 200/µL) showed a modest CD4 T-cell recovery (138 ± 46 cells/µL at baseline vs. 440 ± 448 cells/µL at month 8), and their CD8 T cells increased from 90 ± 41 cells/µL at baseline to 450 ± 242 cells/µL at month 8. HTR developing OIs had lower CD4 (P<0.001) and CD8 T cells (P=0.001) than those without infections, whereas in KTR the risk for OIs seemed restricted to patients with low CD8 T cells. HTR with OIs had a low CD4/CD8 T-cell ratio, whereas KTR had a high CD4/CD8 T-cell ratio. CONCLUSIONS: Determination of T-lymphocyte subsets is a simple and effective parameter to identify patients at risk of developing OIs.

Long-term CD4+ T-cell count evolution after switching from regimens including HIV nucleoside reverse transcriptase inhibitors (NRTI) plus protease inhibitors to regimens containing NRTI plus non-NRTI or only NRTI.

BACKGROUND: Data regarding CD4+ recovery after switching from protease inhibitor (PI)-based regimens to regimens not containing PI are scarce. METHODS: Subjects with virological success on first-PI-regimens who switched to NNRTI therapy (NNRTI group) or to nucleoside reverse transcriptase (NRTI)-only (NRTI group) were studied. The effect of the switch on the ongoing CD4+ trend was assessed by two-phase linear regression (TPLR), allowing us to evaluate whether a change in the CD4+ trend (hinge) occurred and the time of its occurrence. Furthermore, we described the evolution of the frequencies in CD4-count classes across four relevant time-points (baseline, before and immediately after the switch, and last visit). Finally, we explored whether the CD4+ counts evolved differently in patients who switched to NNRTI or NRTI-only regimens by considering: the overall CD4+ trends, the time to CD4+≥ 500/mm3 after the switch, and the area-under-the-curve (AUC) of the CD4+ after the switch. RESULTS: Eight hundred and ninety-six patients, followed for a median of 2,121 days, were included. At TPLR, hinges occurred in 581/844 (68.9%), but in only 40/581 (6.9%) within a time interval (180 days) compatible with a possible relationship to the switch; furthermore, in 19/40 cases, CD4+ counts appeared to decrease after the hinges. In comparison with the NNRTI group, the NRTI group showed CD4+ count greater at baseline (P = 0.0234) and before the switch (P ≤ 0.0001), superior CD4+ T-cell increases after HAART was started, lower probability of not achieving CD4+ ≥ 500/mm3 (P = 0.0024), and, finally, no significant differences in the CD4+ T-cell AUC after the switch after adjusting for possible confounders (propensity score and pre-switch AUC). Persistence at CD4+ < 200/mm3 was observed in 34/435 (7.5%) patients, and a decrease below this level was found in only 10/259 (3.9%) with baseline CD4+ ≥ 350/mm3. CONCLUSIONS: Switching from first-line PI to NNRTI- or NRTI-based regimens did not seem to impair CD4+ trend over long-term follow-up. Although the greater CD4+ increases in patients who switched to the NRTI-only regimen was due to higher CD4+ counts before the switch, several statistical analyses consistently showed that switching to this regimen did not damage the ongoing immune-reconstitution. Lastly, the observation that CD4+ T-cell counts remained low or decreased in the long term despite virological success merits further investigation.

First case in Italy of acquired resistance to oseltamivir in an immunocompromised patient with influenza A/H1N1v infection.

A pandemic influenza A/H1N1v strain with the neuraminidase H274Y mutation was detected in nasal secretions of a 2-year-old leukemic patient with influenza-like illness after 18 days of treatment with oseltamivir. At baseline, no drug-resistant virus was found, while 4 days after treatment initiation a mixture of wild-type and mutated virus was detected. After treatment interruption, the wild type influenza virus re-emerged and became prevalent in nasal secretions after a few days, suggesting the lower fitness of the mutated virus strain. The patient slowly improved concurrently with a decrease in virus load, which resulted negative 42 days after diagnosis. No other drug-resistant influenza A/H1N1v virus strains have been detected in Italy (up to the end of November 2009) since the first case of the novel A/H1N1v virus was identified in the country (May 2009).

Candida infective endocarditis: report of 15 cases from a prospective multicenter study.

Candida species are an uncommon cause of infective endocarditis (IE). Given the rarity of this infection, the epidemiology, prognosis, and optimal therapy of Candida IE are poorly defined. We conducted a prospective, observational study at 18 medical centers in Italy, including all consecutive patients with a definite diagnosis of IE admitted from January 2004 through December 2007.A Candida species was the causative organism in 8 cases of prosthetic valve endocarditis (PVE), 5 cases of native valve endocarditis (NVE), 1 case of pacemaker endocarditis, and 1 case of left ventricular patch infection. Candida species accounted for 1.8% of total cases, and for 3.4% of PVE cases. Most patients (86.6%) had a health care-associated infection. PVE associated with a health care contact occurred after a median of 225 days from valve implantation. Ten patients (66.6%) were treated with caspofungin alone or in combination with other antifungal drugs. The overall mortality rate was 46.6%. Mortality was higher in patients with PVE (5 of 8 cases, 62.5%) than in patients with NVE (2 of 5 patients, 40%). A better outcome was observed in patients treated with a combined medical and surgical therapy.Candida IE should be classified as an emerging infectious disease, usually involving patients with intravascular prosthetic devices, and associated with substantial related morbidity and mortality. Candida PVE usually is a late-onset disease, which becomes clinically evident even several months after an initial episode of transient candidemia.

Acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM), which is classified as a demyelinating disease of the central nervous system (CNS), is a condition that may be regarded as a bridge linking neurology and the infectious diseases. According to the classic definition, ADEM is a monophasic disease that can arise spontaneously; in most cases, however, it is triggered by systemic viral infections or, more rarely, by vaccinations. As the most recent publications on this topic have shown, ADEM can present a relapsing course, being described as "recurrent" if the affected districts are always the same, or "multiphasic" if there is a dissemination in space and time of the lesions, together with a more or less marked association with polyradiculoneuritis. The clinical features and history of the disease create difficulties in differential diagnosis both with encephalomyelitis caused by infectious agents and with noninfectious inflammatory diseases (other demyelinating syndromes, vasculitis, nonvasculitic autoimmune encephalopathies). This paper describes the main features of ADEM, focusing in particular particular on the factors that influence its outcome and can guide the process of differential diagnosis.

Varicella zoster virus meningo-encephalo-myelitis in an immunocompetent patient.

OBJECTIVE: To describe clinical, MRI and cerebrospinal fluid (CSF) features of a varicella zoster virus (VZV) related meningo-encephalo-myelitis (MEM) without rash in an immunocompetent female. PATIENT: An 85 year old immunocompetent woman with mild hyperthermia and acute, severe MEM. INTERVENTION: Serum antibodies and CSF PCR were searched for several viruses. Brain and spinal cord MRI were performed. Immunological profile. TREATMENTS: i.v. acyclovir 30 mg/kg/day; i.v. 6-MP 125 mg/day. RESULTS: Marked CSF lymphomonocytic pleocytosis, blood-brainbarrier damage, and PCR detection of 3.05 X 10 6 copies of VZV DNA. MRI revealed lesions of the meninges, brain and spinal cord. No evidence of immunosuppression. CONCLUSION: We highlight the importance of considering the possibility of VZV related MEM, even in immunocompetent patients. We also provide a MRI description of VZV related multifocal myelitis, not previously available. As supported by other reports, we underline the necessity of a prompt therapeutic intervention in this life-threatening condition.

Severe steroid-resistant post-infectious encephalomyelitis: general features and effects of IVIg.

Based on their presumed immuno-mediated etiology, post-infectious CNS disorders are commonly treated with high-dose steroids. Factors influencing treatment effectiveness, possible alternative options for steroid-resistant cases, and their outcome profiles, remain unclear. We here describe the clinical features, the prognosis and the efficacy of i. v. immunoglobulins (IVIg) in a series of severe ADEM refractory to steroids. We performed an inception cohort study on inpatients of the Neurologic and Infectious Disease Clinics, consecutively admitted over eight years, with a minimum two-year follow-up. Nineteen patients affected by classic and site-restricted ADEM were treated with IVIg after steroid failure. Five other patients received IVIg as first-line treatment due to steroids contraindications: although not included in the analysis, they were monitored for anecdotal comparison. Steroids were administered as IV 6-methylprednisolone (6-MP) 500/1000 mg daily until a maximum dose of 6-8 g; IVIg were administered at 0.4 g/kg/day for 5 days. The outcome was assessed by the Scripps Neurological Rating Scale (SNRS) score with determined periodicity. We observed that steroid-resistant patients showed high prevalence of PNS damage (89%) and myelitis (95 %). Other features were old age, severe disability at onset, and moderate to severe blood-brain-barrier (BBB) damage on CSF. In 10/19 patients (53 %) IVIg were effective, the clinical improvement beginning within the end of the five-day cycle,without relapses. Prominent effects of IVIg were detectable on motor dysfunction. Milder onset disability (p = 0.013) and lower CSF albumin (p = 0.006) were the predictors of IVIg response. Among steroid-free patients, 3/5 were responsive to IVIg. We conclude that IVIg can be useful in a portion of patients with severe steroid-resistant ADEM and prominent motor dysfunction. Unsolved issues regard the usefulness of IVIg in less selected groups, and the spectrum of their clinical effects.

Predictors of clinical progression among HIV-1-positive patients starting HAART with CD4+ T-cell counts > or =200 cells/mm3.

BACKGROUND: Baseline and follow-up predictors of new AIDS-defining events (ADE) or death among patients who started HAART with CD4+ T-cell counts > or =200 cells/mm3 have rarely been assessed simultaneously. METHODS: A prospective observational cohort study (1996-2002) is reported. HIV-infected patients initiating HAART with a CD4+ T-cell count > or =200 cells/mm3 were studied. Baseline and time-varying factors were tested for the prediction of new ADE/death using Cox regression models. RESULTS: A total of 896 subjects were studied over a median of 5.1 years. The incidence of a new ADE was 1.6 (95% confidence interval 1.3-2.1) per 100 person-years. Among baseline factors, higher CD4+ T-cell counts before HAART were associated with lower risk of ADE/death, but not after adjustment for time-varying factors. On a multivariable analysis including both baseline and time-varying covariates, longer delay from HIV diagnosis to HAART was an independent predictor of ADE/death (per year, hazard ratio [HR] 1.06; P = 0.025) and was independent of CD4+ T-cell count before treatment. Longer time spent with HIV RNA <400 copies/ml (per month, HR 0.96; P = 0.003) and higher latest CD4+ T-cell count (per log2 cells/mm3, HR 0.65; P < 0.001) were found to be protective. CONCLUSIONS: Patients with higher CD4+ T-cell counts before HAART initiation had a better prognosis. However, except for the delay in starting HAART, viroimmunological evolution outweighed the effect of baseline factors. Moreover, suppressing HIV replication for as long as possible could improve the clinical outcome. Prospective randomized clinical trials to assess the optimal timing of HAART initiation are both feasible and urgently needed.