Calculated parenteral initial therapy of bacterial infections: Bacterial meningitis.

This is the thirteenth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. Bacterial meningitis is a life-threatening infectious disease with high mortality and disability rates requiring prompt initiation of antimicrobial treatment to lower these rates.

Concentrations of piperacillin-tazobactam in human jaw and hip bone.

OBJECTIVES: It is unclear to what extent pharmacokinetic data from bone outside the facial area can be transferred to the maxillofacial area. The aim of this study was to evaluate the penetration characteristics of piperacillin-tazobactam into human jaw and hip bone as a model for different bone characteristics. MATERIALS AND METHODS: The drug was administered at the start of surgery in a single 15-min intravenous infusion dose (4g piperacillin & 0.5g tazobactam i.v.). Plasma and bone samples of ten patients were analyzed. RESULTS: Mean concentration of piperacillin in plasma was 309microg/ml at 0.5h declining at 4h to 14microg/ml. The respective values for tazobactam were 34microg/ml declining to 2.8microg/ml. The piperacillin-tazobactam ratio dropped during the study interval from 0.5h: 9.2%+/-0.8 to 2h: 7.2%+/-1.1 and 4h: 4.9%+/-0.7. Mean bone concentrations of piperacillin and tazobactam were 9.0+/-11.6microg/g and 1.2+/-1.3microg/g, respectively. Mean penetration ratios for all bone samples were 15% (+/-17) for piperacillin and 13% (+/-14) for tazobactam without a difference between bone of different origin. DISCUSSION: Piperacillin-tazobactam levels in jaw bone tissue after a single dose are sufficient to assure antibacterial activity of the combination and are above the minimal inhibitory concentrations of the most relevant pathogens in head and neck surgery. Our data suggests the use of piperacillin-tazobactam as an alternative for the therapy of severe infections of the head and neck.

[No obvious difference in Streptococcus pneumoniae antibiotic resistance profiles--isolates from HIV-positive and HIV-negative patients]. / Vergleichbare Antibiotikaresistenz von Pneumokokkenisolaten HIV-positiver und -negativer Patienten.

BACKGROUND AND PURPOSE: HIV patients are overexposed to hospital environment, immune suppression, and antibiotic prophylaxes. Therefore, with HIV positive patients an increased risk for resistant bacterial rods is to be expected. The purpose of this case-control study was to determine the susceptibility patterns of pneumococci from adult patients in relation to their HIV status and to compare both patient groups. PATIENTS AND METHODS: Between January 2001 and December 2005, samples from internal medicine patients of one university hospital laboratory were investigated on culture of Streptococcus pneumoniae and in case of a positive vial, a resistance test was done by agar diffusion method. All patients with culture-confirmed infection due to pneumococci underwent a standardized retrospective evaluation in regard to demographic and clinical characteristics including HIV status. RESULTS: A total amount of 135 Streptococcus pneumoniae cultures could be assigned to 64 HIV-positive (A) and 71 HIV-negative patients (B), with susceptibility results for 134 isolates. Full susceptibility was seen in 44 (69.8% [A]) versus 42 (59.2% [B]) samples, reduced susceptibility ("intermediate-susceptible") was found in eight (12.7% [A]) versus 17 (23.9% [B]). Eleven (17.5% [A]) and twelve (16.9% [B]), respectively, out of all pneumococci were tested resistant to at least one antibiotic. Among these, resistance to erythromycin was most relevant (11.1% [A] and 11.3% [B]). None of the tested rods was resistant to penicillin. All differences between groups for susceptibility testing were not found significant. HIV-negative patients were significantly older, needed more often hospitalization and intensive care, and cultures for pneumococci were more frequently positive in primary sterile materials, such as cerebrospinal fluid and blood. The difference concerning death within 28 days following positive sample was just not significant as well as in immune suppression status of patients. HIV patients experienced more frequently an infection relapse and were more frequently smokers. CONCLUSION: No obvious difference in pneumococci resistance patterns was observed between HIV-positive and HIV-negative adult patients. The absence of resistance to penicillin underscores the importance of beta-lactams in case of typical community-acquired pneumonia; therefore, this class of antibiotics should be included in treatment guidelines as first-line drugs also for HIV patients. HIV-negative controls of this study were more aged and suffered from a higher morbidity, however, the fact that they were not significantly less immune suppressed may be special character of a university hospital control patient group. HIV patients presented in an earlier stage of their pneumococcal disease, probably due to a direct access to tertiary hospital medical supply. A higher relapse rate underscores the importance of pneumococcal vaccination for HIV patients.

Is TNF-alpha a prognostic factor in patients with sepsis?

OBJECTIVE: To determine tumor necrosis factor-alpha (TNF-alpha) levels in a prospective study in 58 hospitalized patients in a department of internal medicine (63 episodes, 29 in immunocompromised patients) during a 7-month period. METHODS: Patients fulfilling the following criteria were included: clinical evidence of acute infection, temperature >38.2 degrees C, tachycardia >90 beats/min, tachypnea >20 breaths/min. Samples were taken from day 1 up to day 13 after an infection was diagnosed, and TNF-alpha was determined by enzyme immunoassay. RESULTS: In 29 episodes (46.0%) the infection was microbiologically documented. The median of the TNF-alpha levels in the Gram-negative episodes was significantly higher than that in the Gram-positive episodes (p=0.002). Thirteen of 63 episodes (20.6%) had a fatal outcome. With respect to all measured values, the non-survivors had a significantly higher median of TNF-alpha levels than the survivors (p=0.0001). There was, however, great interpatient and intrapatient variability in TNF-alpha levels; thus, no unequivocal correlation between TNF-alpha and outcome could be documented. CONCLUSIONS: Our data indicate that the influence of the infecting organism on TNF-alpha kinetics is less pronounced than that of the underlying disease.

Comparison of BacT/Alert and BACTEC NR 860 blood culture systems in a laboratory not continuously staffed.

OBJECTIVE: To evaluate the performance of continuously working blood culture systems in a discontinuous laboratory system. METHODS: The systems used were BacT/Alert (Organon Teknika Corp., Durham, NC) and BACTEC NR 860 (Becton Dickinson Diagnostic Instruments, Sparks, Md) in a comparison in a laboratory staffed 8 1/2 h on Mondays to Fridays and 4 1/2 h on Saturdays. Blood culture bottles (BacT/Alert aerobic and anaerobic, BACTEC NR 26 A and NR 27 A) were received thrice daily. RESULTS: From 1824 pairs of blood culture vials, 110 clinically significant microorganisms were recovered by both BACTEC and BacT/Alert, 43 by BACTEC alone, and 33 by BacT/Alert alone. The differences between the systems in total recovery and in recovery of individual species were not statistically significant. The average detection times were 13.36 h for BACTEC and 13.93 h for BacT/Alert (P>0.1). These times represent only 35.6% (BACTEC) and 32.6% (BacT/Alert) of the total timespans from collection of blood to informing the ward of a positive result (tcrd, clinically relevant detection time). If 24 h per day blood culture processing conditions and continuous transport of vials to the laboratory had been available, these percentages would have risen to 87% (BACTEC) and 87.5% (BacT/Alert). Under such 'ideal' conditions, ttrd could have been reduced by 22.16 h using BACTEC and by 26.81 h using BacT/Alert. The BacT/Alert system showed more false-positive results than the BACTEC system (80 (4.39%) versus 23 (1.26%), P<0.001). CONCLUSIONS: No time benefit for detection of positive blood cultures is gained with continuously measuring systems, if loading and processing of vials is organized discontinuously, as in our laboratory.