Giacomo Zanelli

Staphylococcus aureus nasal carriage in the community: a survey from central Italy.

Recently, concern has increased regarding the spread of methicillin-resistant Staphylococcus aureus (MRSA) in the community. We studied 812 subjects from central Italy to establish the rates of nasal carriage of S. aureus, and antibiotic susceptibility patterns, in the community. The prevalence of S. aureus nasal carriage was 30.5%. Only one subject, with predisposing risk factors for acquisition, was identified as carrier of MRSA (prevalence of 0.12%). The presence of MRSA in the community of our area still appears to be a rare event. Among methicillin-susceptible S. aureus (MSSA) isolates, a surprisingly high rate (18%) of resistance to rifampin was observed.

Large Oligoclonal Outbreak Due to Klebsiella pneumoniae ST14 and ST26 Producing the FOX-7 AmpC β-Lactamase in a Neonatal Intensive Care Unit

ABSTRACT A large outbreak caused by expanded-spectrum cephalosporin-resistant Klebsiella pneumoniae (ESCRKP) was observed in a neonatal intensive care unit (NICU) in central Italy. The outbreak involved 127 neonates (99 colonizations and 28 infections, with seven cases of sepsis and two deaths) over a period of more than 2 years (February 2008 to April 2010). Characterization of the 92 nonredundant isolates that were available for further investigation revealed that all of them except one produced the FOX-7 AmpC-type β-lactamase and belonged to either sequence type 14 (ST14) or ST26. All of the FOX-7-positive isolates were resistant to cefotaxime, ceftazidime, and piperacillin-tazobactam, while 76% were susceptible to cefepime, 98% to ertapenem, 99% to meropenem, and 100% to imipenem. The two carbapenem-nonsusceptible isolates had alterations in the genes encoding outer membrane proteins K35 and K36, which resulted in truncated and likely nonfunctional proteins. The outbreak was eventually controlled by the reinforcement of infection control measures based on a multitiered interventional approach. This is the first report of a large NICU outbreak caused by ESCRKP producing an AmpC-type enzyme. This study demonstrates that AmpC-type enzyme-producing strains can cause large outbreaks with significant morbidity and mortality effects (the mortality rate at 14 days was 28.5% for episodes of sepsis), and it underscores the role of laboratory-based surveillance and infection control measures to contain similar episodes.

Muscular-skeletal cryptococcosis in a patient with idiopathic CD4+ lymphopenia

A healthy 27-year-old woman presented, four months after childbirth, ingravescent pain and claudication of the left lower limb. Magnetic Resonance Imaging of the lumbosacral and iliac regions showed widespread muscular-skeletal lesions. The patient underwent surgery; Cryptococcus neoformans was isolated from surgical samples. Liposomal amphotericin B, fluconazole and itraconazole were administered. Laboratory findings showed lymphocytopenia, with reduction of CD4+ lymphocytes (23 cells per cubic millimeter) in the absence of HIV infection and any other defined immunodeficiency. This is a rare case of muscular-skeletal cryptococcal infection isolated in a subject affected with idiopathic CD4+ lymphocytopenia.

Cutaneous leishmaniasis: usefulness of PCR on paraffin-embedded skin biopsies as part of routine investigation

Human cutaneous leishmaniasis (CL) caused by Leishmania infantum is an endemic disease in Italy (Gramiccia, 2003). Its true incidence is probably under-estimated because the clinical pictures are extremely variable, the lesions can self-cure, and the usual method of diagnosis — the microscopical demonstration of amastigotes in skin biopsies — is not very sensitive (Faber et al., 2003). Although PCR-based assays can increase the sensitivity of CL diagnosis (Motazediam et al., 2002; Safaei et al., 2002; Muller et al., 2003; Cordoba Lanus et al., 2005), in Italy such assays are still largely confined to reference centres and research applications. The aim of the present, retrospective study, which was based on archived, paraffin-embedded skin biopsies, was to assess the potential value of PCR in the routine diagnosis of CL.

Five-Year Retrospective Italian Multicenter Study of Visceral Leishmaniasis Treatment

ABSTRACT The treatment of visceral leishmaniasis (VL) is poorly standardized in Italy in spite of the existing evidence. All consecutive patients with VL admitted at 15 Italian centers as inpatients or outpatients between January 2004 and December 2008 were retrospectively considered; outcome data at 1 year after treatment were obtained for all but 1 patient. Demographic characteristics, underlying diseases, diagnostic procedures, treatment regimens and outcomes, as well as side effects were recorded. A confirmed diagnosis of VL was reported for 166 patients: 120 (72.3%) immunocompetent, 21 (12.6%) patients with immune deficiencies other than HIV infection, and 25 (15.1%) coinfected with HIV. Liposomal amphotericin B (L-AmB) was the drug almost universally used for treatment, administered to 153 (92.2%) patients. Thirty-seven different regimens, including L-AmB were used. The mean doses were 29.4 ± 7.9 mg/kg in immunocompetent patients, 32.9 ± 8.6 mg/kg in patients with non-HIV-related immunodeficiencies, and 40.8 ± 6.7 mg/kg in HIV-infected patients (P < 0.001). The mean numbers of infusion days were 7.8 ± 3.1 in immunocompetent patients, 9.6 ± 3.9 in non-HIV-immunodeficient patients, and 12.0 ± 3.4 in HIV-infected patients (P < 0.001). Mild and reversible adverse events were observed in 12.2% of cases. Responsive patients were 154 (93.3%). Successes were 98.4% among immunocompetent patients, 90.5% among non-HIV-immunodeficient patients, and 72.0% among HIV-infected patients. Among predictors of primary response to treatment, HIV infection and age held independent associations in the final multivariate models, whereas the doses and duration of L-AmB treatment were not significantly associated. Longer treatments and higher doses of L-AmB were not able to significantly modify treatment outcomes either in the immunocompetent or in the immunocompromised population.

Treatment of Visceral Leishmaniasis: a Five Years Retrospective Italian Multicentric Study

ABSTRACT The treatment of visceral leishmaniasis (VL) is poorly standardized in Italy in spite of the existing evidence. All consecutive patients with VL admitted at 15 Italian centers as inpatients or outpatients between January 2004 and December 2008 were retrospectively considered; outcome data at 1 year after treatment were obtained for all but 1 patient. Demographic characteristics, underlying diseases, diagnostic procedures, treatment regimens and outcomes, as well as side effects were recorded. A confirmed diagnosis of VL was reported for 166 patients: 120 (72.3%) immunocompetent, 21 (12.6%) patients with immune deficiencies other than HIV infection, and 25 (15.1%) coinfected with HIV. Liposomal amphotericin B (L-AmB) was the drug almost universally used for treatment, administered to 153 (92.2%) patients. Thirty-seven different regimens, including L-AmB were used. The mean doses were 29.4 ± 7.9 mg/kg in immunocompetent patients, 32.9 ± 8.6 mg/kg in patients with non-HIV-related immunodeficiencies, and 40.8 ± 6.7 mg/kg in HIV-infected patients (P < 0.001). The mean numbers of infusion days were 7.8 ± 3.1 in immunocompetent patients, 9.6 ± 3.9 in non-HIV-immunodeficient patients, and 12.0 ± 3.4 in HIV-infected patients (P < 0.001). Mild and reversible adverse events were observed in 12.2% of cases. Responsive patients were 154 (93.3%). Successes were 98.4% among immunocompetent patients, 90.5% among non-HIV-immunodeficient patients, and 72.0% among HIV-infected patients. Among predictors of primary response to treatment, HIV infection and age held independent associations in the final multivariate models, whereas the doses and duration of L-AmB treatment were not significantly associated. Longer treatments and higher doses of L-AmB were not able to significantly modify treatment outcomes either in the immunocompetent or in the immunocompromised population.

Is Rotavirus a Hepatotropic Virus

Dear Editor, We read with interest a recent article by Teitelbaum [1] about rotavirus and hypertransaminasemia. In our experience (personal data, unpublished), not only do we confirm frequent mild transaminase elevation during rotavirus gastroenteritis, but we have also documented a true case of ‘‘hepatitis’’ associated with it. In December 2007, a 5-yearold girl was admitted to the Infectious Diseases Clinic at Siena University (Italy) with fever, vomiting, and diarrhoea. At physical examination she was suffering and dehydrated, her abdomen was painful, and there was hepatomegaly. Laboratory data showed leukocytes 2,540 cells/mm (range, 4,800–10,800), C-reactive protein 8.88 mg/dl (normal value \ 1.0), kaliemia 3.6 mEq/l (range, 3.8–5.5), sodium 128 mEq/l (range, 135–150), aspartate aminotransferase 448 UI/l (normal value \ 40), and alanine aminotransferase 225 UI/l (normal value \ 40), with bilirubin, creatinine phosphokinase, haemoglobin, and other biochemical parameters within normal ranges. An ultrasound evaluation of the abdomen confirmed liver enlargement; chest radiograph and electrocardiogram were negative. Stool antigen testing was positive for rotavirus; no other pathogens were cultured from faeces or blood. Serology for HAV, HBV, HCV, and EBV was negative. Intravenous rehydration was started, initially with antibiotic therapy, with a rapid improvement of symptoms, and the child was discharged in good health and with normalized laboratory data after 9 days. There was no history of previous liver disease or recent drug consumption, and a previous liver test showed normal transaminase values. Considering the concurrence of the gastroenteritis and the lack of evidence of other causes, these data suggest that the transitory liver alterations observed were caused by the rotavirus. As suggested by Teitelbaum in the title of his paper [1], this case seems to confirm the ability of rotavirus to involve the liver during infection, like other minor hepatotropic viruses. While a slight elevation of transaminase levels during rotavirus infection is frequent, to our knowledge this is the first case of mild rotavirus-associated ‘‘hepatitis’’ [1–4].

Listeria meningoencephalitis and anti-GQ1b antibody syndrome

We report the first case of Listeria monocytogenes meningoencephalitis associated with anti-GQ1b antibody syndrome in an immunocompetent adult. A prompt diagnosis, made thanks to the multidisciplinary contribution, allowed a combined therapeutic approach leading to final favourable outcome, despite several intercurrent complications.

Impact of transmitted HIV-1 drug resistance on the efficacy of first-line antiretroviral therapy with two nucleos(t)ide reverse transcriptase inhibitors plus an integrase inhibitor or a protease inhibitor

Objectives To examine the impact of transmitted drug resistance (TDR) on response to first-line regimens with integrase strand transfer inhibitors (INSTIs) or boosted protease inhibitors (bPIs). Methods From an Italian observational database (ARCA) we selected HIV-1-infected drug-naive patients starting two NRTIs and either an INSTI or a bPI, with an available pre-ART resistance genotype. The endpoint was virological failure (VF; plasma HIV-1 RNA >200 copies/mL after week 24). WHO surveillance drug resistance mutations and the Stanford algorithm were used to classify patients into three resistance categories: no TDR (A), TDR but fully-active ART prescribed (B), TDR and at least low-level resistance to one or more prescribed drug (C). Results We included 1365 patients with a median follow-up of 96 weeks (IQR 54-110): 1205 (88.3%) starting bPI and 160 (11.7%) INSTI. Prevalence of TDR was 6.1%, 12.5%, 2.6% and 0% for NRTI, NNRTI, bPI and INSTI, respectively. Cumulative Kaplan-Meier estimates for VF at 48 weeks were 11% (95% CI 10.1%-11.9%) for the bPI group and 7.7% (95% CI 5.4%-10%) for the INSTI group. In the INSTI group, cumulative estimates for VF at 48 weeks were 6% (95% CI 4%-8%) in resistance category A, 5% (95% CI 1%-10%) in B and 50% (95% CI 30%-70%) in C (P < 0.001). Resistance category C [versus A, adjusted hazard ratio (aHR) 12.6, 95% CI 3.2-49.8, P < 0.001] and nadir CD4 (+100 cells/mm3, aHR 0.6, 95% CI 0.4-0.9, P = 0.03) predicted VF. In the bPI group, VF rates were not influenced by baseline resistance. Conclusions Our data support the need for NRTI resistance genotyping in patients starting an INSTI-based first-line ART.

Non-granulomatous cerebellar infection by Acanthamoeba spp. in an immunocompetent host

Acanthamoeba spp. is a free-living amoeba, frequently involved in keratitis by contact lens in immunocompetent hosts. Anecdotal reports associate Acanthamoeba spp. as a cause of severe granulomatous encephalitis in immunocompromised and, less frequently, in immunocompetent subjects. Data regarding clinical and therapeutic management are scanty and no defined therapeutic guidelines are available. We describe an unusual case of non-granulomatous Acanthamoeba cerebellitis in an immunocompetent adult male, with abrupt onset of neurological impairment, subtle hemorrhagic infarction at magnetic resonance imaging, and initial suspicion of cerebellar neoplasm. Histopathological findings of excised cerebellar mass revealed the presence of necrosis and inflammation with structure resembling amoebic trophozoites, but without granulomas. Polymerase chain reaction from cerebellar tissue was positive for Acanthamoeba T4 genotype. Due to gastrointestinal intolerance to miltefosine, the patient was treated with long-term course of fluconazole and trimethoprim/sulphamethoxazole, obtaining complete clinical and neuroradiological resolution.