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Purpose To determine the baseline antibiotic susceptibility patterns of conjunctival and nasopharyngeal flora isolated from patients undergoing intravitreal (IVT) injections for choroidal neovascularization (CNV). Design Prospective, observational study. Participants Forty-eight eyes of 24 patients undergoing unilateral IVT injections for CNV. Methods Bilateral conjunctival and unilateral nasopharyngeal cultures on the treatment side were taken before application of any topical medications. Main Outcome Measures Bacterial isolates were identified and tested for antibiotic susceptibility to 16 different antibiotics using the Kirby-Bauer disc diffusion technique. Results A total of 57 bacterial isolates were obtained from the conjunctiva of 48 eyes. Coagulase-negative staphylococci (CNS) accounted for 37 of the 57 isolates (65%). The most common CNS organisms were Staphylococcus epidermidis and Staphylococcus lugdunensis accounting for 73% and 11% of CNS isolates, respectively. More than half of S. epidermidis isolates demonstrated some level of resistance to ofloxacin and levofloxacin, and 33% and 37% of isolates showed some level of resistance against gatifloxacin and moxifloxacin, respectively. Some 60% and 30% of CNS isolates were resistant to ≥3 and ≥5 antibiotics, respectively. Among the 24 nasopharyngeal cultures, 8 (33%) grew Staphylococcus aureus , and 1 of the 8 isolates (13%) was resistant to all penicillin, cephalosporin, macrolide, and fluoroquinolone antibiotics tested. Conclusions Our results demonstrate subtantial levels of resistance to third- and fourth-generation fluoroquinolones and multiresistance among ocular CNS isolated from patients undergoing IVT injections for CNV. Financial Disclosure(s) The authors have no proprietary or commercial interest in any materials discussed in this article.

Achromobacter xylosoxidans (formerly Alcaligenes xylosoxidans) is a rare but important cause of bacteremia in immunocompromised patients, and strains are usually multiply resistant to antimicrobial therapy. We report an immunocompromised patient with hyper-immunoglobulin M syndrome who suffered from 14 documented episodes of A. xylosoxidans bacteremia. Each episode was treated and resulted in rapid clinical improvement, with blood cultures testing negative for bacteria. Between episodes, A. xylosoxidans was isolated from an excised right axillary lymph node, whereas the culture of the central venous catheter, removed at the same time, was negative. Multiple cultures from sputum, stool, and urine samples, as well as from gastrointestinal biopsies or environmental sources, were negative. Results from antibiotic sensitivity testing and pulsed-field gel electrophoresis suggested that a single strain of A. xylosoxidans caused the recurrent bacteremias in this patient; this strain originated from persistently infected lymph nodes. Lymphoid hyperplasia is a prominent characteristic of hyper-IgM syndrome and may serve as a source of bacteremia with low-pathogenicity organisms.

A simple clinical index can be utilized to identify occult bacterial infections in the critical care unit. Use of this index enables the critical care physician to estimate the likelihood of occult infection, thus reducing and directing the diagnostic effort. This article reviews nonspecific screening tests used in the index.

Summary Appropriate early antimicrobial therapy of patients with serious infections caused by S. aureus is well recognized as an important factor for a favorable outcome. The fact that MRSA strains often are multi-resistant leaves only few antibiotics available for the therapy of MRSA infections. As a consequence, clinicians in many countries resort to the use of glycopeptides to broadly cover the patient for a possible MRSA infection until the results of cultures and susceptibility testing are available. Such use of glycopeptides clearly increases the selective pressure for vancomycin resistance, an issue which is of great concern in view of the increasing problem with vancomycin-resistant enterococci. Moreover, there is an additional risk that the overuse of vancomycin may lead to the development of vancomycin-resistant stains of MRSA, a situation for which no treatment would be available! Finally, therapy with glycopeptides results in higher cost as compared to s-lactamase stable penicillins due to the higher cost of the drug as well as higher associated costs of therapy such as vancomycin levels. Rapid/accurate detection of MRS A is important in order to decrease the use of glycopeptide antibiotics. Furthermore, rapid and accurate detection increases the possibilities of reducing or even controlling the spread of MRSA. DNAbased rapid assays have been developed and should be available commercially soon. At present, these rapid assays are also being evaluated against methicillin resistance in coagulase negative staphylococci (CNST). Such resistance is also encoded by the mecA gene. CNST infections are increasing, especially in immunocompromised patients with methicillin resistance being very common in these strains. The existing phenotypic susceptibility methods detection of methicillin resistance is so unreliable when testing CNST that many clinicians choose to treat with glycopeptide antibiotics regardless of the test results.