Bloodstream infections in hospitalized adults with dengue fever: Clinical characteristics and recommended empirical therapy.

BACKGROUND: Dengue is an important mosquito-borne tropical viral disease and dual infection, though rare, has been regarded as a risk factor for severe disease and mortality. However, few studies focused on bloodstream infections (BSIs) and empirical antibiotic therapy rarely addressed. METHODS: Dengue patients with concurrent or subsequent BSIs between July 1 and December 31, 2015 were included. Clinical information, laboratory data, and drug susceptibility data were collected. RESULTS: Totally 80 patients, with an in-hospital mortality rate of 32.5%, were included and categorized into three groups. 32 patients in Group I (BSI onset within 48 h after admission), 32 in Group II (between 48 h and one week), and 16 in Group III (more than one week). Patients in Group I were older (mean age: 75.6 vs. 72.6 or 69.6 years; P = 0.01) and had a higher Charlson comorbidity index (3.1 vs. 1.8 or 1.9; P = 0.02) than those in Group II or III. Streptococcus species (28.9%, 11/38) and Escherichia coli (23.7%, 9/38) were major pathogens in Group I. Enterobacteriaceae (38.2%, 13/34) isolates predominated in Group II. Fatal patients more often received inappropriate empirical antibiotic than the survivors (61.5% vs. 35.2%; P = 0.03). According to susceptibility data, pathogens in Group I and II shared similar susceptibility profiles, and levofloxacin, cefepime, or piperacillin/tazobactam, can be empirically prescribed for those hospitalized within one week. CONCLUSIONS: BSI pathogens vary among dengue patients. For adults with dengue and suspected BSI hospitalized within one week, empirical antimicrobial agents are recommended.

Comparison of empirical therapy with cefoperazone/sulbactam or a carbapenem for bloodstream infections due to ESBL-producing Enterobacteriaceae.

Objectives: Carbapenems are widely recommended for the treatment of infections caused by ESBL producers however, non-carbapenem ß-lactams such as ß-lactam/ß-lactamase inhibitor combinations (BLBLIs) deserve consideration for the treatment of ESBL infections. Cefoperazone/sulbactam is one of the most commonly used BLBLIs in China; however, few outcome studies have been reported. In this study, we evaluated and compared the clinical efficacy of cefoperazone/sulbactam with that of a carbapenem in the treatment of bloodstream infections (BSIs) caused by ESBL-producing Enterobacteriaceae. Methods: Patients with monomicrobial ESBL-producing Enterobacteriaceae BSIs empirically treated with cefoperazone/sulbactam or a carbapenem were included. Outcomes of interest were clinical response and 14 day mortality. To make a comparison of the efficacy of cefoperazone/sulbactam and a carbapenem more accurate, propensity score analysis was performed. Results: No statistically significant differences in success rates or 14 day mortality were found between the cefoperazone/sulbactam (n = 17) and carbapenem (n = 46) groups. In the propensity score analysis with 17 case-control pairs, the success rate in the cefoperazone/sulbactam group (70.6%, 12/17) was lower than that in the carbapenem group (94.1%, 16/17), but the difference was not significant (P = 0.175). Sepsis-related mortality and 14 day mortality rates did not significantly differ either (P = 1.000 for both). In the cefoperazone/sulbactam group, 66.7% (2/3) of the patients with a Pitt bacteraemia score ≥5 died within 14 days, whereas none (0/14) of the patients with a Pitt bacteraemia score <5 died within 14 days (P = 0.022). Conclusions: This study showed that cefoperazone/sulbactam had a lower success rate and a higher 14 day mortality rate compared with carbapenems, although the differences were not statistically significant because of the small patient numbers. Further evaluation of cefoperazone/sulbactam is needed.

Resolution of infectious parameters after antimicrobial therapy in patients with ventilator-associated pneumonia.

Although recommended durations of antimicrobial therapy for ventilator-associated pneumonia (VAP) range from 7 to 21 d, these are not based on prospective studies and little is known about the resolution of symptoms after start of antibiotics. Resolution of these symptoms was investigated in 27 patients. VAP was diagnosed on clinical, radiographic, and microbiological criteria, including quantitative cultures of bronchoalveolar lavage. All patients received appropriate antibiotic therapy. Highest temperatures, leukocyte counts, Pa(O(2))/FI(O(2)) ratios, and semiquantitative cultures of endotracheal aspirates were recorded from start of therapy until Day 14. Resolution was defined as the first day that these parameters fulfilled the following definition: temperature < or = 38 degrees C, leukocytes < or = 10 x 10(9)/L, Pa(O(2))/FI(O(2)) ratio > or = 25 kPa, and no or +1 of bacterial growth of etiologic pathogens in cultures of endotracheal aspirate. VAP was caused by Enterobacteriaceae (n = 14), P. aeruginosa (n = 7), S. aureus (n = 6), H. influenzae (n = 3), and S. pneumoniae (n = 1). H. influenzae and S. pneumoniae were eradicated from tracheal aspirates, whereas Enterobacteriaceae, S. aureus, and P. aeruginosa persisted, despite in vitro susceptibility to antibiotics administered. Significant improvements were observed for all clinical parameters, most apparently within the first 6 d after start of antibiotics. Newly acquired colonization, especially with P. aeruginosa and Enterobacteriaceae, occurred in the second week of therapy. Six patients developed a recurrent episode of VAP, four of them with P. aeruginosa. Clinical responses to therapy for VAP occur within the first 6 d of therapy, endotracheal colonization with Gram-negative bacteria persists despite susceptibility to therapy, and acquired colonization usually occurs in the second week of therapy and frequently precedes a recurrent episode.

Differential distributions in tissues and efficacies of aztreonam and ceftazidime and in vivo bacterial morphological changes following treatment.

The differential tissue distributions of aztreonam and ceftazidime within fibrin clots infected with Pseudomonas aeruginosa, Enterobacter cloacae, and Serratia marcescens, their efficacies, and the in vivo bacterial morphological changes induced by these drugs were evaluated. Rabbits were given intravenously a single dose of 100 mg of either agents/kg of body weight. In the cores of the clots, the peak levels of both drugs were much lower than those observed in the peripheries and in serum. Aztreonam's half-lives within the peripheries and in the cores of the fibrin clots were up to six times higher than observed in serum, while ceftazidime's half-lives in clots were twice that observed in serum. This resulted in a much greater penetration ratio for aztreonam than for ceftazidime. Both drugs controlled the growth of P. aeruginosa in vivo, but E. cloacae and S. marcescens responded better to ceftazidime. Morphological changes were more abundant in the peripheries than in the cores of the clots. In the control group, P. aeruginosa's morphology in the cores was different than that in the peripheries of the clots. Against P. aeruginosa, aztreonam did induce morphological changes in the cores while ceftazidime did not. Electron microscopic studies revealed that morphological changes associated with aztreonam seemed different than those of ceftazidime. Along with elongation of bacteria, more bow tie and herniated bacteria were observed with aztreonam. Though both agents selectively affect PBP 3, as manifested by elongated bacteria, they induce in the peripheries of the clots thickening, breaks, and detachment in bacterial cell walls, alterations which are generally associated with antibiotics affecting PBP 1a and 1b.

Use of ciprofloxacin in an infant with ventriculitis.

Ciprofloxacin was used successfully in a neonate with ventriculitis caused by a multiply resistant strain of Enterobacter cloacae. Limited pharmacokinetic data indicated that adequate concentrations of drug could be attained in cerebrospinal fluid.

Clinical and laboratory studies with amikacin in newborns, infants, and children.

Thirty (86%) of 35 infants and older children with proven gram-negative sepsis had a complete clinical remission after treatment with amikacin. In 27 (82%) of 33 infectious episodes for which bacteriologic results were available before and after treatment, the organism was eradicated. The dosage of amikacin was either 7.5 mg/kg or 15 mg/kg given intramuscularly at 12-hr intervals. No adverse clinical effects or laboratory abnormalities were observed during treatment, which lasted from five to 14 days. All bacteria were sensitive to amikacin when tested by the disk diffusion method, and all but a single strain of Pseudomonas were sensitive when tested by the agar dilution method. Assays of serum and urine demonstrated adequate levels of amikacin after single intramuscular injections of 3.75 or 7.5 mg/kg; simultaneous assays of serum and cerebrospinal fluid in two cases demonstrated comparable concentrations of drug suggestive of a high degree of penetration into the cerebrospinal fluid in two cases demonstrated comparable concentrations of drug suggestive of a high degree of penetration into the cerebrospinal fluid during infection. Serial measurements of amikacin in serum from 0.5 to 12 hr after administration of single doses of 7.5 mg of drug/kg to six newborns revealed no significant differences in the concentrations achieved with intramuscular or intravenous administration of the drug.

Amikacin therapy for severe gram-negative sepsis: efficacy in infections involving gentamicin-resistant organisms.

Thirty-eight patients with 41 serious infections due to gram-negative bacteria were treated with amikacin. Twenty of these infections involved organisms that were resistant to gentamicin. The results of therapy in 31 of the infections satisfied the criteria for bacteriologic and clinical cure. Eight patients with urinary tract infections and obstructive uropathy had a good clinical response, but routine follow-up cultures of urine at 30 days were positive. Two patients had persistent sepsis and were considered therapeutic failures. Toxicity to the eighth nerve was documented in three of 31 patients for whom routine audiometric testing was performed. These results indicate that amikacin is effective in the treatment of serious infections due to gram-negative bacilli and is particularly useful in infections involving resistant organisms.