Antimicrobial use and microbiological testing in district general hospital ICUs of the Veneto region of north-east Italy.

International - predominantly American - studies undertaken in the ICUs of teaching centres show that inadequate antibiotic therapy increases mortality and length of stay. We sought to ascertain whether this also pertains to smaller ICUs in the Veneto region of north-east Italy. To the best of our knowledge, this is the first such survey in the Veneto area or in Italy as a whole. A retrospective, observational study was performed across five general-hospital ICUs to examine appropriateness of microbiological sampling, empirical antibiotic adequacy, and outcomes. Among 911 patients (mean age, 65.8 years ± 16.2 SD; median ICU stay, 17.0 days [IQR, 8.0-29.0]), 757 (83.1 %) were given empirical antibiotics. Treatment adequacy could be fully assessed in only 212 patients (28.0 %), who received empirical treatment and who had a relevant clinical sample collected at the initiation of this antibiotic (T0). Many other patients only had delayed microbiological investigation of their infections between day 1 and day 10 of therapy. Mortality was significantly higher among the 34.9 % of patients receiving inadequate treatment (48.6 % vs 18.80 %; p < 0.001). Only 32.5 % of combination regimens comprised a broad-spectrum Gram-negative ß-lactam plus an anti-MRSA agent, and many combinations were irrational. Inadequate treatment was frequent and was strongly associated with mortality; moreover, there was delayed microbiological investigation of many infections, precluding appropriate treatment modification and de-escalation. Improvements in these aspects and in antibiotic stewardship are being sought.

Deep tissue biopsy vs. superficial swab culture monitoring in the microbiological assessment of limb-threatening diabetic foot infection.

AIMS: The results of ulcer swabbing vs. deep tissue biopsy have been compared prospectively in 29 diabetic patients with limb-threatening foot infection, to investigate the effectiveness and reliability of each method, and to evaluate whether any of the two could be more suitable for the microbiological follow-up of severe lesions. METHODS: Microbiological samples were collected by using both methods at fixed intervals after therapy commencement (i.e. at day 0, 7, 14, and 30). Statistical comparison was performed between the results of each sampling procedure after the end of follow-up. RESULTS: At enrolment, the mean number of isolates per patient was 2.34 by swabbing and 2.07 by tissue biopsy sampling; the rate of isolation for anaerobes with the two methods was 35% and 25%, respectively; no statistical differences could be observed between the two procedures in terms of either species or frequency of isolation. Anaerobic species were never detected after the first 2 weeks of appropriate treatment, and those ulcers which were still active at day 30 yielded almost exclusively Gram-positive bacteria. At the end of follow-up, deep tissue cultures appeared to exhibit a higher diagnostic sensitivity with respect to swabs. CONCLUSIONS: Swabbing and deep tissue cultures appear to be equally reliable for the initial monitoring of antimicrobial treatment in severe diabetic foot infection. However, our experience seems to suggest that deep tissue might be more sensitive than swabbing for monitoring those isolates that have been selected for antibiotic resistance, i.e. those from ulcers that are still active after 30 days of treatment.

Randomized prospective controlled trial of recombinant granulocyte colony-stimulating factor as adjunctive therapy for limb-threatening diabetic foot infection.

Adult diabetic patients admitted to our Diabetes Center from September 1996 to January 1998 for severe, limb-threatening foot infection were consecutively enrolled in a prospective, randomized, controlled clinical study aimed at assessing the safety and efficacy of recombinant human granulocyte colony-stimulating factor (G-CSF) (lenograstim) as an adjunctive therapy for the standard treatment of diabetic foot infection. Forty patients, all of whom displayed evidence of osteomyelitis and long-standing ulcer infection, were randomized 1:1 to receive either conventional treatment (i.e., antimicrobial therapy plus local treatment) or conventional therapy plus 263 microg of G-CSF subcutaneously daily for 21 days. The empiric antibiotic treatment (a combination of ciprofloxacin plus clindamycin) was further adjusted, when necessary, according to the results of cultures and sensitivity testing. Microbiologic assessment of foot ulcers was performed by both deep-tissue biopsy and swab cultures, performed at enrollment and on days 7 and 21 thereafter. Patients were monitored for 6 months; the major endpoints (i.e., cure, improvement, failure, and amputation) were blindly assessed at weeks 3 and 9. At enrollment, both patient groups were comparable in terms of both demographic and clinical data. None of the G-CSF-treated patients experienced either local or systemic adverse effects. At the 3- and 9-week assessments, no significant differences between the two groups could be observed concerning the number of patients either cured or improved, the number of patients displaying therapeutic failure, or the species and number of microorganisms previously yielded from cultures at day 7 and day 21. Conversely, among this small series of patients the cumulative number of amputations observed after 9 weeks of treatment appeared to be lower in the G-CSF arm; in fact, only three patients (15%) in this group had required amputation, whereas nine patients (45%) in the other group had required amputation (P = 0.038). In conclusion, the administration of G-CSF for 3 weeks as an adjunctive therapy for limb-threatening diabetic foot infection was associated with a lower rate of amputation within 9 weeks after the commencement of standard treatment. Further clinical studies aimed at precisely defining the role of this approach to this serious complication of diabetes mellitus appear to be justified.