IDSA and ICAAC Conference Coverage: Part III
Note: The following summaries conclude our coverage of the 37th ICAAC conference and the 35th Annual Meeting of the IDSA. Many of these summaries are extracted only from the published abstracts, and it is possible that some of the material presented at the conference may have differed. sd
Infectious disease consultation on patients with S. aureus bacteremia was associated with significantly fewer relapses (P = 0.01), despite their dealing with significantly more complicated cases. (IDSA-409.)
Analysis of an antibiotic control program in a 624-bed university teaching hospital in place for 11 years found that 4374 changes were made in response, with $423 saved per change. (IDSA-424.)
Intervention by infectious disease consultants in the use of amphotericin B lipid complex at an academic medical center resulted in an estimated cost avoidance of $166,350 to $305,360 over a six-month period. (IDSA-428.)
Only 50% of Indian travelers to India from Toronto had sought pre-travel advice, mostly from family practitioners, and just 30% were using malaria prophylaxis, but only 6% were using an approved regimen. Fewer than 10% were using insect protection measures. Family practitioners were more likely to have inappropriately prescribed chloroquine than travel clinics or tropical medicine physicians (P < 0.001). (LM-82.) This finding once again stresses the need for travelers to seek assistance from trained, knowledgeable physicians.
Six (6%) of 105 individuals ages 18-35 years who traveled to developing countries for 1-6 months had serological evidence of having acquired infection with Helicobacter pylori, while none of 85 matched non-traveling controls did so (P = 0.03). Corrected for travel time, the rates were six per 305 travel months vs. 0 for 474 travel months (P = 0.002). (K-58.) Thus, H. pylori becomes the latest addition to the ever-expanding list of travel-related infections.
Vascular access devices
A randomized comparison of the use of polyurethane triple lumen central venous catheters impregnated with either minocycline and rifampin or chlorhexidine and silver sulfadiazine found that the former was associated with significantly lower rates of catheter colonization and catheter-related bloodstream infections. (LB-22.)
Another example of the need for the hospital epidemiologist to occasionally think like a criminal investigator was presented. A nosocomial outbreak of HCV infection among patients in an ambulatory surgical center proved to be due to apparent contamination of fentanyl citrate because of tampering by a scrub technician with chronic HCV infection. (J-28.)
Epidural catheters
The overall incidence of epidural catheter infections in 200 patients (100 each with intractable pain and pregnancy) was 10.5%; there was a significant difference in infection rate between catheters kept in place for less than three days (17.3%) and those kept in place for four days or more (33.3%; P < 0.001). Colonization (> 15 cfu) of the catheter was more common among those with infection (46.4%) than those without (4.6%; P < 0.01). (J-108.)
A retrospective analysis of 14 epidural catheter-associated infections found that the mean time to onset was 4.1 + 2.8 days (range, 1-12 days). Eight patients had meningitis and four had "spinal" abscesses, while two had only soft tissue infection. (In my experience, most epidural catheter-related infections are less serious than those reported here, suggesting that many such infections may have been overlooked.) Both gram positive and negative organisms were etiologic. There were no fatalities, but four had neurologic sequelae. (J-109.)
Sinusitis
Twenty-seven (26 with orotracheal intubation) mechanically ventilated patients with suspected sinusitis underwent percutaneous maxillary sinus puncture. Pathogens were recovered from 13 (76%) of 16 not receiving antibiotics and from only three (30%) of 10 receiving such therapy. Thirteen patients had a culture of their endotracheal aspirate at the time of sinus puncture, and in 12 of these, the aerobic pathogen isolate differed from that recovered from the sinus culture. (J-130.) Thus, cultures of endotracheal aspirate do not reflect the sinus flora in mechanically ventilated patients, and sinus aspiration is seldom rewarding in patients already receiving antibiotics.
Urinary tract infection
An analysis of 809 hospitalized, newly bladder-catheterized patients found that 63 (7.9%) developed urinary tract infection. A comparison of those with and without infection, however, could detect no difference in the frequency of bladder symptoms, and most were afebrile. Only two catheterized patients developed bacteremia with the same species of bacteria present in the bladder, and, in both cases, an infected intravascular line could not be excluded as the source. (IDSA-45.)
Pneumonia
Mechanically ventilated patients were randomized to topical antimicrobial prophylaxis (vancomycin, gentamicin, colistin) applied to the oropharynx every six hours or to no intervention. Topical prophylaxis was associated with significantly reduced colonization of the oropharynx and trachea but not the stomach. Ventilator-associated pneumonia was diagnosed in 10/87 (11.5%) prophylaxis patients and 38/139 (27.3%) controls (P = 0.003). Mortality was not significantly different between the groups. (J-48.)
IV alatrovafloxacin followed by oral trovafloxacin was compared to ciprofloxacin plus clindamycin in 267 patients with nosocomial pneumonia. The clinical success rate was 77% for the former and 78% for the latter regimen. (LM-74.)
VRE
Admission to a hospital room recently occupied by a patient colonized with VRE was an independent risk factor (RR = 17.3; P = 0.02) for VRE colonization. Apparent transmission from the environment was confirmed by DNA typing in four of four pairs of isolates studied. (IDSA-46.)
Antibiotic resistance
Institution of restriction of quinolone prescription in a Greek tertiary care hospital led to an 80% decrease in their use and was followed by a significant decrease in resistance to these drugs. (E-11.)
Trovafloxacin
The pharmacokinetics of trovafloxacin are not altered in AIDS patients, nor by hepatic impairment. (A-64, A-65.) The dosing of this fluoroquinolone does not require adjustment in the presence of renal impairment, and serum concentrations are not affected by dialysis. (A-66.)
Like other fluoroquinolones, trovafloxacin penetrates well into prostatic tissue. (A-67.) PET scanning in healthy volunteers given 200 mg daily by mouth for 5-8 days found mean peak concentrations greater than 20 mg/L in liver, kidney, spleen, and lung and approximately 2.6 mg/L in brain. (A-68.) CSF penetration in children was approximately 22-30% and should be adequate to treat meningitis due to the pneumococcus, meningococcus (this has been confirmed in a clinical study), and Hemophilus influenzae. (A-105.)
CMV infection and rejection have decreased in relative prominence as causes of fever in liver transplant recipients in Pittsburgh. In the investigators’ estimation, 58% of febrile episodes whose etiology remained unclear despite three days of diagnostic evaluation proved to be due to HHV-6. The presence of otherwise unexplained leukopenia was an important clue to the presence of HHV-6 infection in these patients. (J-95.) Another study found that HHV-6 infection in renal transplant patients was significantly associated with anemia and thrombocytopenia as well as leukopenia. (IDSA-705.)
Renal allograft recipients who were either CMV seronegative with a seropositive donor (high risk) or CMV seropositive (moderate risk) were randomized to receive either valaciclovir (2 g qid) or placebo. Valaciclovir prevented or delayed CMV disease by approximately 80% in both groups. (LB-25.)
Fifty consecutive episodes of leukocytosis in liver transplant recipients were reviewed. One-third occurred within three days of transplantation, were unaccompanied by fever, and resolved spontaneously. Infections accounted for 28%, were accompanied by fever in 57%, and had a median time to onset of 25 days. In 22%, leukocytosis occurred 7-14 days after transplantation, was unaccompanied by fever, resolved spontaneously, and was thought to be related to resolution of pretransplant hypersplenism with release of sequestered granulocytes and platelets. (IDSA-703.)
Sixteen recipients of first cadaveric renal grafts with immediate functional recovery, all receiving cyclosporin, were randomized to receive either ceftazidime or imipenem/cilastatin for a short course of prophylaxis. Although there was no apparent effect on cyclosporin blood levels, serum creatinine levels were lower and tubular damage (as determined by urinary excretion of N-acetyl-beta-D-gluosaminidase) was less in the imipenem/cilastatin recipients. This is consistent with the hypothesis that cilastatin can reduce cyclosporin-induced tubular damage. (IDSA-171.)
Fludarabine treatment of refractory chronic lymphocytic leukemia is associated with a marked increase in severe opportunistic infections. (IDSA-710.)
Influenza
It was recently reported that topical administration of the neuraminidase inhibitor zanamivir (GG167) was effective in the treatment of influenza A and B infections (N Engl J Med 1997;337:874-880). Oral administration of another neuraminidase inhibitor, GS4104, begun within 28 hours of intranasal inoculation of influenza A/Texas/91 (H1N1), decreased the duration of symptoms by almost half of that seen in a placebo-treated group. (LB-26.)
Enterovirus
Thirty-nine adults with clinically suspected enterovirus meningitis were randomized to receive either pleconaril (VPL 63843) or placebo. The mean time to clinical recovery in the pleconaril group was decreased, relative to the placebo group, to 4.0 from 9.5 days (P = 0.008). The mean time to return to work was decreased to 8.0 from 14.25 days. (LB-27.)
Hepatitis viruses
An evaluation of a group of men with naturally acquired hepatitis A infection found that they were viremic, as determined by PCR, for as long as 30 days prior to the onset of symptoms. (IDSA-103.)
The administration of lobucavir, a guanosine nucleoside analog, to patients with chronic hepatitis B virus infection was associated with a two- to four-fold reduction in HBV DNA levels. (H-32.)
Lamivudine administration in the CAESAR study of antiretroviral therapy of HIV infection was associated with a significant reduction in HBV DNA in coinfected individuals. (H-31.)
Protease inhibitor therapy of coinfected HIV-infected patients with either indinavir or saquinavir had no effect on HCV viral load. (H-26.)
Varicella
Nine varicella-exposed children who, by history, were varicella-susceptible were given the Oka/Merck vaccine within three days of onset of lesions in the index case. While four vaccinees developed no lesions, five developed 5-83 lesions. The mean number of lesions in the six index cases was 252, while in the nine vaccinees it was only 14.9. Thus, post-exposure varicella vaccination appeared to have some degree of efficacy in exposed susceptibles. (IDSA-614.)
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content