Achilleas Gikas

Prospective evaluation of effects of broad-spectrum antibiotics on gastrointestinal yeast colonization of humans.

This study evaluated the effects of broad-spectrum antibiotics on the gastrointestinal (G.I.) yeast flora of humans and correlated the findings with those obtained from a mouse model of G.I. colonization by Candida albicans. We prospectively studied 46 adult cancer patients who received one of five broad-spectrum antibiotics (ceftriaxone, ceftazidime, ticarcillin-clavulanic acid, imipenem-cilastatin, and aztreonam) as therapy for infections. Quantitative examination of yeast colonization of stools was conducted at the baseline, at the end of antibiotic treatment, and 1 week after discontinuation of therapy. Antibiotics with anaerobic activity (ticarcillin-clavulanic acid) or high G.I. concentrations (ceftriaxone) caused a higher and more sustained increase in G.I. colonization by yeasts than did antibiotics with poor anaerobic activity (ceftazidime and aztreonam) or a low G.I. concentration (imipenem-cilastatin). These results were similar to those obtained with a mouse model of G.I. colonization by C. albicans that involved the same antibiotics. Hence, the mouse model may be useful for evaluation of yeast colonization of the human G.I. tract.

Prospective study of the impact of broad-spectrum antibiotics on the yeast flora of the human gut

The effects of four antibiotics on the yeast flora of the human gut were evaluated. Forty adult cancer patients who received therapy with amoxicillin-clavulanate, ciprofloxacin, sulfamethoxazole-trimethoprim or ampicillin were studied prospectively. Quantitative stool cultures for yeasts were performed immediately before, at the end of and one week after the end of the antibiotic treatment. Amoxicillin-clavulanate caused a higher and more persistent increase in gastrointestinal colonization by yeasts compared to ciprofloxacin, sulfamethoxazole-trimethoprim or ampicillin. The present results are similar to those obtained in a mouse model of gastrointestinal colonization byCandida albicans when the same antibiotics were used.

Antibiotic use and the risk of carbapenem-resistant extended-spectrum-β-lactamase-producing Klebsiella pneumoniae infection in hospitalized patients: results of a double case–control study

OBJECTIVES To identify the roles of various antibiotics as risk factors for carbapenem-resistant extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae (KP) infection (ESBL-KP infection). METHODS Data were collected over 26 months in a tertiary care university hospital with established endemicity of carbapenem-resistant ESBL-KP (ESBL-CRKP). Using a case-case-control design, patients who presented an infection caused by carbapenem-susceptible ESBL-KP (ESBL-CSKP) and patients with ESBL-CRKP infection were compared with a common control group of hospitalized patients. Effects of treatment and duration of treatment with antibiotics were examined, adjusting for major non-antibiotic risk factors and controlling for confounding effects among the antibiotics via logistic regression models. RESULTS Ninety-six ESBL-CRKP cases, 55 ESBL-CSKP cases and 151 controls were analysed. Multivariate analysis, adjusting for major non-antibiotic risk factors, showed that the risk of ESBL-CRKP infection rose with increasing duration of prior treatment with β-lactam/β-lactamase inhibitor combinations [odds ratio (OR) 1.15 per day increase; P = 0.001] and revealed that increased duration of treatment with fluoroquinolones amplified the impact of exposure to carbapenems (and vice versa) on ESBL-CRKP infection risk (OR 1.02 for interaction term; P = 0.009). Duration of prior treatment with fluoroquinolones was also associated with increased risk of ESBL-CSKP infection (OR 1.07 per day increase; P = 0.028), while prior receipt of carbapenems presented a protective effect against ESBL-CSKP infection (OR 0.21; P = 0.003). CONCLUSIONS This study highlights the major role of treatment and duration of treatment with β-lactam/β-lactamase inhibitor combinations and combinations of carbapenems with fluoroquinolones. Clinicians should counterweight the potential benefits of administering these antibiotics against the increased risk of ESBL-CRKP infection.

Murine typhus in Greece: epidemiological, clinical, and therapeutic data from 83 cases

Over a period of 5 years (1993-97), 83 cases of murine typhus were identified and studied in the city of Chania, on the island of Crete. Of these cases, 4.8% were registered in 1993, 19.3% in 1994, 47.0% in 1995, 10.8% in 1996, and 18.1% in 1997. The greatest incidence of the disease occurred during the third trimester of the year. Direct contact with rats was noted in 45 (54.2%) of 83 patients. Two strains of Rickettsia typhi were isolated in cell cultures. The predominant clinical manifestations were: fever (100%), headache (88%), chills (86.7%), and rash (79.5%). In 4 of the patients (4.8%), the disease was complicated by acute renal failure, and in 4 other patients (4.8%), by pulmonary consolidations. The outcome under appropriate treatment was favourable for all patients.

Activities of sparfloxacin, azithromycin, temafloxacin, and rifapentine compared with that of clarithromycin against multiplication of Mycobacterium avium complex within human macrophages.

The activities of sparfloxacin, azithromycin, temafloxacin, and rifapentine against two virulent strains of the Mycobacterium avium complex isolated from patients with AIDS were evaluated in a model of intracellular infection and were compared with that of clarithromycin. Human monocyte-derived macrophages were infected with the M. avium complex at day 6 of culture. The intracellular CFU was counted 60 min after inoculation. The intracellular and supernatant CFU was counted on days 4 and 7 after inoculation. The concentrations used, which were equal to peak levels in serum, were 10 micrograms of rifapentine per ml (MICs for the two strains, 4 and 16 micrograms/ml), 4 micrograms of clarithromycin per ml (MICs, 8 and 4 micrograms/ml), 1 microgram of azithromycin per ml (MICs, 32 and 16 micrograms/ml), 4 micrograms of temafloxacin per ml (MICs, 2 and 16 micrograms/ml), and 1 microgram of sparfloxacin per ml (MICs, 0.5 and 2 micrograms/ml). Compared with controls on day 7 after inoculation, clarithromycin (P less than 0.001), sparfloxacin (P less than 0.001), and azithromycin (P less than 0.001 for the first strain, P less than 0.02 for the second) slowed intracellular replication. Rifapentine (P less than 0.001) and temafloxacin (P less than 0.001) slowed intracellular replication of the first strain but not of the second strain. Azithromycin plus sparfloxacin was as effective as sparfloxacin alone. In this macrophage model, sparfloxacin or clarithromycin (difference not significant) exhibited a better efficacy than rifapentine, azithromycin, or temafloxacin against intracellular M. avium complex infection.

Surgical Site Infections, International Nosocomial Infection Control Consortium (INICC) Report, Data Summary of 30 Countries, 2005–2010

OBJECTIVE  To report the results of a surveillance study on surgical site infections (SSIs) conducted by the International Nosocomial Infection Control Consortium (INICC). DESIGN  Cohort prospective multinational multicenter surveillance study. SETTING  Eighty-two hospitals of 66 cities in 30 countries (Argentina, Brazil, Colombia, Cuba, Dominican Republic, Egypt, Greece, India, Kosovo, Lebanon, Lithuania, Macedonia, Malaysia, Mexico, Morocco, Pakistan, Panama, Peru, Philippines, Poland, Salvador, Saudi Arabia, Serbia, Singapore, Slovakia, Sudan, Thailand, Turkey, Uruguay, and Vietnam) from 4 continents (America, Asia, Africa, and Europe). PATIENTS  Patients undergoing surgical procedures (SPs) from January 2005 to December 2010. METHODS  Data were gathered and recorded from patients hospitalized in INICC member hospitals by using the methods and definitions of the Centers for Disease Control and Prevention National Healthcare Safety Network (CDC-NHSN) for SSI. SPs were classified into 31 types according to International Classification of Diseases, Ninth Revision, criteria. RESULTS  We gathered data from 7,523 SSIs associated with 260,973 SPs. SSI rates were significantly higher for most SPs in INICC hospitals compared with CDC-NHSN data, including the rates of SSI after hip prosthesis (2.6% vs. 1.3%; relative risk [RR], 2.06 [95% confidence interval (CI), 1.8-2.4]; P < .001), coronary bypass with chest and donor incision (4.5% vs. 2.9%; RR, 1.52 [95% CI, 1.4-1.6]; [P < .001); abdominal hysterectomy (2.7% vs. 1.6%; RR, 1.66 [95% CI, 1.4-2.0]; P < .001); exploratory abdominal surgery (4.1% vs. 2.0%; RR, 2.05 [95% CI, 1.6-2.6]; P < .001); ventricular shunt, 12.9% vs. 5.6% (RR, 2.3 [95% CI, 1.9-2.6]; P < .001, and others. CONCLUSIONS  SSI rates were higher for most SPs in INICC hospitals compared with CDC-NHSN data.

Newer macrolides as empiric treatment for acute Q fever infection

ABSTRACT The effectiveness of newer macrolides in acute Q fever for 113 patients was recorded. The mean times to defervescence were 2.9 days for doxycycline and 3.3, 3.9, 3.9, and 6.4 days for clarithromycin, roxithromycin, erythromycin, and β-lactams, respectively (P < 0.01 for macrolides versus β-lactams). We conclude that macrolides may be an adequate empirical antibiotic therapy for acute Q fever.

Activities of clarithromycin, sulfisoxazole, and rifabutin against Mycobacterium avium complex multiplication within human macrophages.

The activities of clarithromycin, sulfisoxazole, and rifabutin against three virulent strains of Mycobacterium avium complex isolated from patients with acquired immunodeficiency syndrome were evaluated in a model of intracellular infection. Human monocyte-derived macrophages were infected at day 6 of culture with M. avium complex. Intracellular bacteria were counted 60 min after inoculation. Extra- and intracellular bacteria were counted at days 4 and 7 after inoculation. The concentrations used were 4 micrograms of clarithromycin per ml (MICs for the three strains, 4, 4, and 4 micrograms/ml), 50 micrograms of sulfisoxazole per ml (MICs, 50, 25, and 25 micrograms/ml), and 0.5 micrograms of rifabutin per ml (MICs, 2, 0.5, and 0.5 micrograms/ml). Compared with controls, clarithromycin and rifabutin slowed the intracellular replication of the three strains (at day 7 after inoculation, P was less than 0.01 for the first strain and less than 0.001 for the two others). Sulfisoxazole was ineffective against the three strains. Clarithromycin was as effective as rifabutin. Clarithromycin plus rifabutin was as effective as each single agent. Clarithromycin plus sulfisoxazole was as effective as clarithromycin alone.

Simultaneous Detection of “Rickettsia mongolotimonae” in a Patient and in a Tick in Greece

ABSTRACT Rickettsia conorii, a spotted fever group rickettsia which is transmitted by Rhipicephalus sp. complex ticks, was considered until now the only pathogenic rickettsia prevalent in Greece. Here, we report the presence of “Rickettsia mongolotimonae” (proposed name) detected simultaneously in a patient and in a Hyalomma anatolicum excavatum tick, sampled on the patient.

Gram-negative bacteremia in non-neutropenic patients: A 3-year review

SummaryThe causative organisms, clinical manifestations, factors influencing prognosis, and other epidemiological characteristics of 81 episodes of bacteremia due to gram-negative organisms, in non-neutropenic patients, were studied retrospectively during a 3-year period (1992–1994) at the Department of Internal Medicine of the University Hospital of Heraklion, Crete, Greece. The gram-negative bacteremia incidence was 2% and the overall mortality 12%. All 81 patients had fever;Escherichia coli was the most frequent organism isolated (from 47 patients −58%) and was associated with shock (9/47), disseminated intravascular coagulation (DIC) (8/47), anuria (5/47), adult respiratory distress syndrome (ARDS) (3/47), and pneumonia (1/47). Other less frequent gram-negative microorganisms wereKlebsiella spp. (ten patients; 12%),Pseudomonas spp. (7; 7%),Salmonella spp. (5; 6%),Enterobacter spp. (5; 6%),Proteus spp. (3; 3.4%),Stenotrophomonas spp. (3; 3.4%), andAcinetobacter spp. (1; 1.2%). ARDS, shock, DIC, anuria, presence of central venous catheter, urinary catheter, unknown origin of infection and inappropriate treatment were significantly associated with a higher death rate. Early initiation of appropriate therapy was the most important intervention that favorably affected the outcome of gram-negative bacteremias in this patient population.