Evolution of fungemia in an Italian region.

BACKGROUND: Fungemia represents a public health concern. Knowing aetiology and activity of the antifungals is critical for the management of bloodstream infections. Therefore, surveillance on local/international levels is desirable for a prompt administration of appropriate therapy. METHODS: Data on fungi responsible for fungemia and antifungal susceptibility profiles were collected from a laboratory-based surveillance over 2016-2017 in 12 hospitals located in Lombardia, Italy. The trend of this infection in twenty years was analysed. RESULTS: A total of 1024 episodes were evaluated. Rate of candiaemia progressively increased up to 1.46/1000 admissions. C.albicans was the most common species (52%), followed by C. parapsilosis (15%) and C glabrata (13%). As in the previous surveys the antifungal resistance is rare (echinocandins<2%, fluconazole 6%, amphotericin B 0.6%). Fungi other than Candida were responsible for 18 episodes: Cryptococcus neoformans (5 cases), Fusarium spp. (4), Magnusiomyces clavatus (3), Saccharomyces cerevisiae (3), Rhodotorula spp. (2), Exophiala dermatitidis (1). All fungi, except S.cerevisiae, were intrinsically resistant to echinocandins. Some isolates showed also elevated azole MIC. CONCLUSIONS: No particular changes in terms of species distribution and antifungal susceptibility patterns was noted. However, surveillance programs are needed to monitor trends in antifungal resistance, steer stewardship activities, orient empirical treatment.

Preemptive therapy for systemic and pulmonary human cytomegalovirus infection in lung transplant recipients.

The incidence and treatment of both systemic and pulmonary human cytomegalovirus (HCMV) infection as well as HCMV-specific T-cell immune responses were investigated in 57 consecutive lung transplant recipients (LTR) by using as cutoffs for preemptive therapy: 300 000 DNA copies/mL whole blood for systemic infections and 100 000 DNA copies/mL bronchoalveolar lavage fluid for lung infections. Results showed that out of 29/57 LTR (50.9%) needing preemptive antiviral therapy, 15 (51.7%) reached the blood cutoff, 8 (27.6%) the pulmonary cutoff and 6 (20.7%) both the blood and the lung cutoff (3 simultaneously and 3 subsequently). Recovery of HCMV-specific T-cell immune responses was achieved much earlier for CD8+ than CD4+ T cells. However, protection from HCMV reactivation was conferred by the presence of both arms of the T-cell response. In two LTR reaching the pulmonary cutoff and not preemptively treated, a full HCMV-specific CD4+ and CD8+ T-cell response was associated with resolution of lung infection. Antirejection steroid therapy suppressed T-cell immune responses, thus facilitating HCMV reactivation. In conclusion, in LTR, monitoring HCMV infection in both blood and lungs, may improve preemptive therapy efficacy. In addition, monitoring the HCMV-specific T-cell immune response appears useful for predicting control of HCMV infection in the posttransplant period.

Correlation of rhinovirus load in the respiratory tract and clinical symptoms in hospitalized immunocompetent and immunocompromised patients.

While human rhinoviruses (HRVs) are well accepted as a major cause of common cold syndromes (rhinitis), their role in the etiology of lower respiratory tract infections is still controversial, and their detection in asymptomatic patients is relatively common. The HRV pathogenic role in four groups of hospitalized patients (pediatric immunocompetent and immunocompromised patients, and adult immunocompetent and immunocompromised patients) was investigated by quantifying HRV load in nasopharyngeal aspirates or bronchoalveolar lavage samples by real-time reverse transcription PCR (RT-PCR). Real-time RT-PCR was performed in duplicate on all respiratory samples resulting positive by qualitative RT-PCR. In addition, molecular typing allowed detection of all known HRV species (A, B, and C). In immunocompetent pediatric patients HRVs were mostly associated with lower respiratory tract infections (in the absence of other viral agents) and wheezing, when viral load was > or =10(6) RNA copies/ml. In young immunocompromised patients (stem cell transplantation recipients), an inverse correlation between HRV persistence over time and time at which the infection occurred after transplantation was observed, whereas in adult immunocompromised patients (lung transplant recipients) HRVs could be detected at a medium-low level (<10(5) RNA copies/ml) in bronchoalveolar lavage samples taken routinely from asymptomatic patients. In conclusion, when detected at high viral load, HRVs may cause severe upper and lower respiratory tract infections, whereas when detected at a medium-low viral load, an event more frequent in immunocompromised subjects, they may represent only bystander viruses.

Correlation of viral load as determined by real-time RT-PCR and clinical characteristics of respiratory syncytial virus lower respiratory tract infections in early infancy.

BACKGROUND: In infants hospitalized for a lower respiratory tract infection (RTI) caused by respiratory syncytial virus (RSV), the correlation between viral load (VL) and patient clinical characteristics remains to be defined. OBJECTIVES: To define this correlation. STUDY DESIGN: prospective study of 47 infants admitted to hospital in the period November 2006-May 2007 with a diagnosis of lower RTI. Nasopharyngeal aspirates (NPAs) were taken at admission, discharge, and at post-discharge control visits. VL was quantified by real-time RT-PCR for RSV subgroups A and B. RESULTS: Patients with bronchiolitis were compared with young patients with lower RTI other than bronchiolitis. Patients with bronchiolitis had a significantly lower age than patients with other syndromes, and a significantly longer duration of symptoms. Duration of hospitalization was not different in the two groups of patients, and was not related to RSV subgroup or viral coinfection. A sustained decrease in VL was observed in the general patient population between admission, discharge and post-discharge follow-up visits. CONCLUSIONS: (i) patients with bronchiolitis were significantly younger than patients with other lower RTIs; (ii) symptom duration was significantly longer in patients with bronchiolitis; (iii) RSV VL significantly decreased between admission and discharge.

Clinical severity and molecular typing of human rhinovirus C strains during a fall outbreak affecting hospitalized patients.

BACKGROUND: The circulation rate and the clinical severity of infections caused by members of the new human rhinovirus C (HRV-C) species remain to be defined. OBJECTIVES: To investigate the epidemiologic and clinical impact of HRV-C strains in a fall outbreak interesting hospitalized patients. STUDY DESIGN: HRV species (A-C) were determined by phylogenetic analysis following amplification of two genome regions (5'NCR and VP4/VP2) by RT-PCR. HRV species were correlated with age, respiratory tract involvement, clinical symptoms, and HRV load in respiratory secretions. RESULTS: During the first week of the period October-November 2008, single HRV infections were associated with 95% of all respiratory syndromes affecting hospitalized patients. Then, HRV infections (single+coinfections) interested about 90% of positive samples until the end of October, when they declined in frequency until reaching about 30% at the end of November. Overall, 104 HRV strains were detected and, of these, 90 could be classified by phylogenetic analysis, as follows: 45 HRV-A, 12 HRV-B, 28 HRV-C, and 5 human enterovirus D strains. HRV-C identity was confirmed by detection of cis-acting replication elements (cre) in 23/23 strains. As for severity of respiratory syndromes, unlike HRV-A and HRV-B strains, HRV-C strains were responsible for a significantly higher rate (p<0.05) of lower respiratory tract infections in the pediatric as compared to adult patient population. CONCLUSIONS: HRV-C strains have been shown to circulate at a rate intermediate between HRV-A and HRV-B strains, showing a greater degree of clinical severity in the pediatric population.