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Infectious Diseases Update
Abstracts of current literature on epidemiology, diagnosis, and treatment
Series Editor: Jihad Slim, MD
BEDSIDE CLINICAL PREDICTORS OF BACTEREMIA
Researchers prospectively observed a cohort of patients admitted to a university hospital in Medellin, Columbia, in order to
identify clinical variables that could be used in a prediction
model for bacteremia. From September 2001 to February 2002,
complete clinical and laboratory data were collected for 500 patients who had at least 2 blood cultures requested, were hospitalized for 48 hours or more, and were over age 14 years. Exclusion criteria included pregnancy, recent transplant, incomplete/
unavailable records, and death/discharge ≤ 24 hours after initial
culture was requested. Data were then analyzed for their association with the outcome variable, which was the presence of bacteremia as demonstrated by a positive blood culture result. Significant predictors of bacteremia were age ≥ 30 years (odds ratio
[OR], 2.07 [95% confidence interval {CI}, 1.19–3.60]), heart
rate of ≥ 90 bpm (OR, 1.90 [95% CI, 1.13–3.17]), temperature
≥ 37.8°C (OR, 2.42 [95% CI, 1.41–4.14]), a leukocyte count
≥ 12 × 103/m3 (OR, 2.40 [95% CI, 1.41–4.10]), central venous
catheter use (OR, 1.89 [95% CI, 1.02–3.50]), and duration of
hospital stay ≥ 10 days (OR, 2.02 [95% CI, 1.25–3.24]). The
Hosmer-Lemeshow test revealed a goodness-of-fit of 2.99 (P =
0.9817), and the area under the receiver operating characteristics curve was 0.7186, which respectively indicate excellent calibration and acceptable discrimination. Simple variables observed during physical examination or results obtained from
routine laboratory tests are associated with bacteremia and
should be used to prioritize requests for blood culture analysis.
Jaimes F, Arango C, Ruiz G, et al. Predicting bacteremia at the bedside. Clin Infect Dis 2004;38:357–62.
CEREBROSPINAL FLUID ABNORMALITIES IN SYPHILIS
PATIENTS
In order to define clinical and laboratory features that identify
patients with neurosyphilis, researchers enrolled patients diagnosed with syphilis (according to 1993 Centers for Disease Control and Prevention guidelines) from 8 sites in the United States.
Patients (N = 326) were recruited from outpatient sexually transmitted diseases, infectious diseases, ophthalmology, lumbar
puncture, and general medicine clinics; emergency departments; and inpatient medicine and neurology wards. Patients
previously diagnosed with neurosyphilis were excluded. Earlystage syphilis was significantly associated with a serum rapid plasma reagin (RPR) titer ≥ 1:32 (P < 0.001). Early-stage syphilis also
was associated with HIV infection (P < 0.001). 65 patients
(20.1%) were identified with neurosyphilis. Early syphilis increased the odds of neurosyphilis in a univariate analysis but not
in multivariate analyses. Multivariate analyses revealed that
serum RPR titer ≥ 1:32 conferred a 10.85-fold (95% CI,
2.69–43.80; P < 0.001) increased risk of neurosyphilis in HIVuninfected patients and 5.98-fold (95% CI, 2.43–14.73; P <
0.001) in HIV-infected patients. A peripheral blood CD4 cell
count ≤ 350 cells/µL conferred a 3.10-fold increased risk of
neurosyphilis in HIV-infected patients. Results were similar
when neurosyphilis was defined more strictly as cerebrospinal
fluid VDRL test result. Results of serum RPR titer can predict the
chance of developing neurosyphilis, and positive HIV status confers greater risk of neurosyphilis.
Marra CM, Maxwell CL, Smith SL, et al. Cerebrospinal fluid abnormalities in patients with syphilis: association with clinical and laboratory features. J Infect Dis 2004;189:369–76.
POSSIBLE TRANSMISSION OF VARIANT CREUTZFELDTJAKOB DISEASE VIA BLOOD TRANSFUSION
The authors conducted a surveillance study in the United Kingdom to determine whether variant Creutzfeldt-Jakob disease
(vCJD) could be transmitted through blood transfusions. In
1997, the UK national CJD surveillance unit and the UK national blood service implemented a surveillance system for vCJD,
and workers began searching records from 1980 to the present
for blood donors who later became vCJD cases. 15 such donors
were identified, and their blood products were traced to 48 recipients, one of whom was identified as developing vCJD
6.5 years after transfusion. In 1996, this patient received a blood
transfusion from a donor who later developed vCJD. The recipient died approximately 13 months after onset of symptoms.
The recipient’s age was greater than that of most patients who
develop vCJD, and statistical analysis revealed that the chance of
observing vCJD in the absence of transfusion is about 1 in 15,000
and 1 in 30,000. Coincidental infection, therefore, was thought
to be unlikely; however, dietary exposure to bovine spongiform
encephalitis, which is causally linked to vCJD, still is possible. Of
the 48 blood recipients identified, 31 died, 17 within 1 year of
transfusion. Cause of death was established for 28 patients. As of
18 Dec 2003, the remaining 17 patients were alive and had not
developed vCJD. vCJD may be transmissible through blood
transfusions.
Llewelyn CA, Hewitt PE, Knight RSG, et al. Possible transmission of
variant Creutzfeldt-Jakob disease by blood transfusion. Lancet 2004;
363:417–21.
Dr. Slim is an assistant professor of medicine, Seton Hall University, South
Orange, NJ. Abstracts written by Rita E. Gould, Hospital Physician.
Copyright 2004 by Turner White Communications Inc., Wayne, PA. All rights reserved.
10 Hospital Physician April 2004
www.turner-white.com