Evaluation of predictors of third-generation cephalosporin non-susceptibility and factors affecting recurrence or death in bacteremia caused by Citrobacter freundii complex, Enterobacter cloacae complex, and Klebsiella aerogenes.

Factors involved in the susceptibility of third-generation cephalosporins (3GCs) to bacteremia caused by Citrobacter freundii complex, Enterobacter cloacae complex, and Klebsiella aerogenes were investigated based on a case-case-control design. Antimicrobial therapy administered 30 days prior to bacteremia and hospitalization within 90 days were common risk factors for the 3GC susceptible and 3GC non-susceptible groups, while hospitalization from an institution or another hospital was a specific risk factor for the 3GC non-susceptible group. We also attempted to examine the factors affecting the clinical outcome of bacteremia. Hospitalization more than 14 days before the onset of bacteremia was an independent factor indicating poor clinical outcome. In contrast, the implementation of source control was an independent predictor of successful treatment. Although a longer hospital stay before the onset of bacteremia was associated with worse clinical outcomes, implementation of source control may have contributed to improved treatment outcomes for bacteremia.

The Clinical Evaluation of Third-generation Cephalosporins As Definitive Therapy for Enterobacter spp. and Klebsiella aerogenes Bacteremia.

Objective Third-generation cephalosporins (3GCs) may be susceptible in vitro to Enterobacter spp. and Klebsiella aerogenes. However, treatment with mainly fourth-generation cephalosporins or carbapenems is currently recommended. Diversification of antimicrobial agents in therapy is required to avoid the selection pressure of resistant organisms by broad-spectrum antimicrobial agents. This study investigated the clinical efficacy of 3GC therapy for Enterobacter spp. and Klebsiella aerogenes bacteremia in a multicenter, retrospective, observational study. Methods Patients with Enterobacter spp. or Klebsiella aerogenes detected in blood cultures and treated with a susceptible antimicrobial agent were included in the study. Propensity score matching was performed to align patient background bases, and clinical outcomes between the 3GC and non-3GC groups were compared. Treatment success was defined as having no need for treatment escalation or the addition of other antimicrobial agents, no recurrence, or no death within 30 days. Results The study included 188 cases, of which 57 and 131 were included in the 3GC and non-3GC treatment groups, respectively; 53 patients in each group were matched by propensity score matching. There were no significant differences between groups in rates of switching to a susceptible antimicrobial or adding another agent, relapse within 30 days, or death within 30 days. In the 3GC group, source control was associated with favorable clinical outcomes. Conclusion Definitive 3GC therapy for susceptible Enterobacter spp. and Klebsiella aerogenes bacteremia is as clinically effective and valuable a targeted therapy as non-3GC therapy and can be implemented under conditions in which infection source control measures are in place.

[Decreased Serum Copper Concentrations by Zinc Administration in Preterm Infants with Hypozincemia Are Associated with a Lower Postmenstrual Age: A Single-center Retrospective Observational Study].

Copper is one of the essential trace elements in humans, and its deficiency causes various diseases. Zinc acetate dihydrate is administered to treat hypozincemia in preterm infants; however, zinc inhibits the gastrointestinal absorption of copper, which may cause copper deficiency. To safely treat hypozincemia in preterm infants, we retrospectively analyzed the factors reducing serum copper concentrations when zinc is administered to preterm infants with hypozincemia. Seventy preterm infants were included in the present study. Serum zinc and copper concentrations, doses, and other clinical characteristics were retrieved from electronic medical records. The administration of zinc acetate dihydrate decreased serum copper concentrations in 21 out of 70 patients. In comparisons between the two groups with and without a decrease in serum copper concentrations, significant differences were observed in postmenstrual age (34.9 and 35.9 weeks, respectively) and serum zinc concentrations (62.0 and 58.0 µg/dL, respectively) at the start of the zinc acetate dihydrate treatment. A logistic regression analysis identified postmenstrual age as a significant factor decreasing serum copper concentrations. In the ROC curve, the cut-off value for postmenstrual age for a decrease in serum copper concentrations was 34.143 weeks. The present results suggest that when zinc acetate dihydrate is administered to preterm infants with a low postmenstrual age who are at higher risk of decreased serum copper concentrations, particularly to those with a postmenstrual age <34 weeks, it is important to consider copper deficiency and periodically measure serum copper concentrations.

Administration of zinc to preterm infants with hypozincemia does not reduce serum copper concentrations in most cases: a single-center retrospective observational study.

BACKGROUND: Zinc is an essential trace element involved in various physiological functions. In Japan, zinc acetate dihydrate is administered to neonates and infants with hypozincemia. Since serum copper concentrations are reduced by the administration of zinc, we retrospectively investigated changes in serum zinc and copper concentrations in preterm infants with hypozincemia receiving zinc acetate dihydrate. METHODS: Sixty-three preterm infants were included in the present study. Serum zinc and copper concentrations, doses, and other clinical characteristics were retrieved from electronic medical records. RESULTS: The medians and interquartile ranges of the dosage and duration of zinc acetate dihydrate were 2.1 (1.8-2.5) mg/kg/day and 12.0 (10.0-13.0) days, respectively. Its administration increased serum zinc concentrations in 39 patients (61.9%) and to more than 70 µg/dL in 16 patients (25.4%). The group with a serum zinc concentration of 70 µg/dL or higher after administration had a significantly higher zinc dose of 2.5 mg/kg/day than the group with a serum zinc concentration of less than 70 µg/dL. Serum copper concentrations did not decrease in 44 patients (69.8%). In the group with a decreased serum copper concentration, postmenstrual age and body weight were significantly lower, while serum zinc concentrations were significantly higher at the start of administration. CONCLUSION: The present results showed that when zinc acetate dihydrate was administered to preterm infants with hypozincemia, it was possible to increase serum zinc concentrations without decreasing serum copper concentrations in many cases. However, caution may be required when administering zinc to preterm infants with a lower postmenstrual age or milder hypozincemia because serum copper concentrations may decrease.