Improved diagnosis of central venous catheter-related bloodstream infections using the HB&L UROQUATTRO™ system.

The diagnosis of catheter-related bloodstream infections (CRBSIs) in febrile patients with indwelling central venous catheters (CVCs) needs improvement. To diagnose CRBSIs more efficiently, we have developed a novel culture approach using the catheter tips removed from febrile patients. CVCs and blood cultures from 1,070 patients with only CVC-related infections were obtained over a period of 3 years (January 2009 to December 2011). The CVCs were evaluated by a semi-quantitative catheter culture method according to Maki's method and by our novel method, which is based on the use of the HB&L UROQUATTRO™ system (Alifax, Padova, Italy). Using our new method, 571 (571/1,070) of the infections were confirmed as CRBSIs. The remaining 487 patients had infections that were associated with hematologic malignancies, neutropenia, prior exposure to antibiotics, and a decreased CVC removal rate. Twelve samples were identified as false-positives. The percentage of patients with CRBSIs confirmed using the HB&L UROQUATTRO™ system was 53.36 % versus 34.95 % (p-value 0.004) using Maki's method (374/1,070 CVC Maki-positive samples). Our results indicate that our new culture method allows for an improved CRBSI diagnosis rate. A significant number of tip cultures (18.41 %) tested positive for CRBSIs using our system but were negative when tested using Maki's method. Moreover, the use of the HB&L UROQUATTRO™ system allowed us to significantly reduce diagnosis time; a negative CRBSI diagnosis could be made within 6 h and a positive diagnosis could be made within 22-28 h.

The combined use of VIGI@ct (bioMérieux) and fluorescent amplified length fragment polymorphisms in the investigation of potential outbreaks.

Even with good surveillance programmes, hospital-acquired infections (HAIs) are not always recognized and this may lead to an outbreak. In order to reduce this risk, we propose a model for prompt detection of HAIs, based on the use of a real-time epidemiological information system called VIGI@ct (bioMèrieux, Las Balmas, France) and on the rapid confirmation or exclusion of the genetic relationship among pathogens using fluorescent amplified length fragment polymorphism (f-AFLP) microbial fingerprinting. We present the results of one year's experience with the system, which identified a total of 306 suspicious HAIs. Of these, 281 (92%) were 'confirmed' by clinical evidence, 16 (5%) were considered to be simple colonization and the latter nine (3%) were archived as 'not answered' because of the absence of the physician's cooperation. There were seven suspected outbreaks; of these, f-AFLP analysis confirmed the clonal relationship among the isolates in four cases: outbreak 1 (four isolates of Pseudomonas aeruginosa), outbreak 2 (three Escherichia coli isolates), outbreak 6 (two Candida parapsilosis isolates) and outbreak 7 (30 ESbetaL-producing Klebsiella pneumoniae subsp. pneumoniae). Based on our results, we conclude that the combination of VIGI@ct and f-AFLP is useful in the rapid assessment of an outbreak due to Gram-positive or Gram-negative bacteria and yeasts.

Requests of medical examinations after pneumococcal & influenza vaccination in the elderly.

BACKGROUND & OBJECTIVES: There are no specific recommendations about pneumococcal vaccination (PV) in Italy. There are limited data on the requests of medical examination or hospitalization due to side effects of pneumococcal vaccination. In the present study we present our analyses on the requests of medical examination due to side effects of pneumococcal vaccination (PV) in 29,086 elderly aged >/=65 yr. METHODS: Vaccination with influenza vaccine (IV) alone or in association with PV was offered during the IV campaign in the winter 1999-2000 in 8 counties of Sicily. General practitioners (GPs) provided the vaccination and, 72 h later, recorded local and systemic side effects by a telephonic interview with the waccinees. GPs recorded also the requests of medical treatments. RESULTS: A total of 16,601 subjects (57.1%) were vaccinated with IV alone and 12,485 (42.9%) with the association IV+PV. Adverse effects were reported by 14.7 per cent of vaccinees. Out of 4,289 subjects with side effects, 305 (7.1%) looked for a medical examination. The factors associated with a significantly increased risk for medical examination after vaccination were symptoms duration >72 h (OR 2.04; 95% CI 1.38-3.01; P=0.0002); local induration (OR 3.26; 95% CI 2.07-5.13; P<0.0001); general malaise (OR 2.05; 95% CI 1.34-3.13; P=0.0009); fever >/=38 degrees C (OR 3.34; 95% CI 1.90-5.86; P<0.0001); myalgia (OR 2.80; 95% CI 1.46-5.37; P=0.0018) and dyspnea (OR 37.86; 95% CI 9.65-148.60; P=0.0001). INTERPRETATION & CONCLUSION: The few requests for medical examination and the low rate of adverse effects confirmed the tolerability and safety of PV+IV; GPs consultation were related to the severity and duration of symptoms, but independent of the type of vaccine administered.

Variables affecting salivary Streptococcus mutans counts in a cohort of 12-year-old subjects.

BACKGROUND: Several factors such as toothbrushing, diet, acidogenic potential of the mutans streptococci strain and site of the carious lesion can modify the salivary Streptococcus mutans (Sm) counts. In the present investigation the effect of some behavioural, clinical and microbiological variables on Sm salivary counts was evaluated in a cohort of 12-year-olds. METHODS: Forty subjects were examined by two calibrated examiners (GC, AL). The number of surfaces either decayed occlusal, decayed smooth or filled and the number of bleeding sextants, (clinical index for oral hygiene) were reported. Saliva was collected using a tongue depressor and was plated onto mitis salivarius agar with bacitracin and 20% sucrose. The presumptive Sm colonies were counted and the concentrations were logarithmically transformed. One Sm strain per subject was identified and the cariogenic potential evaluated as the minimum pH value recorded, during 5 hrs of incubation in 5% sucrose solution. The children's parents or guardians completed a questionnaire concerning the frequency of toothbrushing, the consumption of sweet foods and soft drinks and at what age the children started brushing their teeth. The effect of the explanatory variables on Sm count logarithms was evaluated by stepwise multiple regression. RESULTS: The regressors with significant additional explanatory power were cariogenic potential (b = -1.335, p = 0.00001, R2 increment = 0.312), decayed smooth surfaces (b = -0.456, p = 0.009, R2 increment = 0.114) and bleeding sextants (b = -0.113, p = 0.004, R2 increment = 0.062), whereas the power of filled surfaces was marginally significant (p = 0.08). CONCLUSIONS: On the basis of these results, it is suggested that acidogenicity is not only a cariogenic factor, but also a factor promoting colonization of oral sites by Sm, especially in subjects with a high frequency of sugar consumption.