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The 34th annual meeting of the Infectious Diseases Society of America (IDSA)
took place September 18-20, 1996 in New Orleans. The following is a summary of
selected reports from this meeting.
- Gross PA, et al. Testing Compliance with the IDSA AIDS Prevention
Standards of Care (Hackensack University Medical Center, Newark): The
authors reviewed three standards of care in 116 patients, including 60 from
private practices and 56 from HIV clinics. The results were presented to
physicians, and compliance was then evaluated 11 months later in 1996.
Compliance with CD4 counts at 6 month intervals was 58%, for PCP prophylaxis it
was 90%, and for annual PPD skin test it was 19%. Reevaluation after
notification of these results showed compliance improved to 81%, 93%, and 53%
for the three standards, respectively. The authors concluded that this type of
feedback to participating physicians improved the quality of care.
- Evans SE, et al. HIV, HBV and HCV Prevalence Among Source Patients
Reported to the San Francisco General Needlestick Hotline (San Francisco):
This is a review of 191 needlestick injuries among health care workers. The
frequency in the source patient was 50 (26%) for HIV, 66 (36%) for HCV, and 3
(1.6%) for HBV (by HBsAg). All HIV-infected source patients were known to be
infected at the time of the needlestick injury; thus, serologic testing did not
reveal any unknown infections. Of the 50 source patients with HIV, 21 had been
treated with AZT and 7 had been treated with 3TC. Analysis of patient isolates
revealed AZT resistance (codon 215 mutation) in 15%, and the frequency of
resistance to 3TC (184 codon mutation) was zero. Only two of the source patients
were known to have HCV infection prior to exposure. The authors conclude that
in hospitals like San Francisco General, most of the source patients with HIV
are known to have this infection, but HCV is both common and usually unknown.
- Beekmann SE. Risk Factors for HIV Seroconversion in a Prospective Study
of AZT Post-Exposure Prophylaxis (NIH, Iowa College and San Francisco
General Hospital): The CDC has published a case-control study defining four
risks for HIV transmission that has been reviewed in prior issues of the Hopkins
HIV Report. The present study examines the frequency of these variables in
health care workers with needlestick injuries from an HIV infected source.
Among the 154 exposures, 10 (6%) were deep injuries, 52 (34%) showed visible
blood on the device, 64 (42%) involved needles used in an artery or vein, and
93 (60%) were in source patients with late stage HIV infection (AIDS or a CD4
cell count less than 50 cells/mm3). There were 92 (60%) with 0-1 risk and 2
(1%) with all four risks. No seroconversions were noted.
- Martins MD, et al. Incidence of Symptomatic and Asymptomatic Carriage
of Fluconazole-Resistant Candida in the Oropharynx of HIV-Infected Patients
(Houston): The authors evaluated 125 consecutive HIV-infected adult
patients to determine carriage rates of fluconazole-resistant Candida. Cultures
of the oral cavity were performed, and sensitivity was tested using
standardized techniques. The carriage rate was 81 of 125 (65%) patients; only
32% of the carriers had clinical thrush. Of particular importance was that
non-C. albicans carriage was noted in 27% of the carriers, but thrush was seen
only in those with C. albicans. Fluconazole-resistant strains were seen in 26%
of carriers. The authors concluded that non-C. albicans carriage is common, but
does not appear to cause symptomatic thrush in the absence of C. albicans, and
that asymptomatic carriage of azole-resistant strains is common.
- Revankar SG, et al. Development of Fluconazole Resistance with
Continuous Versus Intermittent Therapy in Oropharyngeal Candidiasis in
HIV-Infected Patients (San Antonio): The authors evaluated 40 patients with
thrush who were randomized to receive continuous or intermittent treatment for
clinical disease using fluconazole (200 mg/day). The mean CD4 cell count was 41
cells/mm3 and the follow-up period averaged 7.6 months. Follow-up cultures
demonstrated a 4-fold rise in MIC to at least 16 fg/ml for 7 of 15 receiving
continuous treatment and 9 of 25 receiving intermittent treatment. This
difference is not statistically significant, though the sample size is too small
to exclude differences. The authors noted that patients with resistant strains
tended to respond well to fluconazole; only one of 40 patients failed to
respond.
- Van Dyke R, et al. Factors in Addition to Viral Load Influence
Maternal-Child Transmission of HIV (7 U.S. sites): The authors used a
standardized protocol prospectively in seven sites to define risk factors for
vertical transmission of HIV. AZT therapy was given to 79% of the participants.
There were 227 evaluable infants, including 20 who had confirmed HIV infection.
In comparing the 11% with vertical transmission to the 89% without vertical
transmission, the former had a higher frequency of injection drug use (30%
versus 20%), a lower median CD4 cell count (372 cells/mm3 versus 465 cells/mm3),
and a higher plasma HIV RNA at delivery (mean of 7,550 copies/ml versus 3,550
copies/ml). None of these differences was statistically significant. The
authors concluded that maternal drug use, viral load at delivery and mode of
delivery were not strong predictors of vertical transmission in this population
in which most received AZT treatment.
Reboli AC, et al. Influenza Vaccination has no Effect on Viral
Load in HIV-Infected Patients with Higher CD4 Cell Counts (Robert Wood
Johnson Medical School and Chiron): The authors studied the effect of influenza
vaccine on 32 patients randomized to receive influenza vaccine (16 participants)
versus placebo (16 patients). All participants had asymptomatic HIV infection
with CD4 cell counts above 200 cells/mm3. Results were evaluated with CD4 cell
counts and quantitative virology before immunization and then at 2, 4, 8, 12 and
26 weeks after. No differences were noted between the two groups for either CD4
cell count or viral burden. (It should be noted that similar negative results
on CD4 cell count and viral burden with influenza vaccine were noted in another
paper from Rush Medical College.)
- Foulds G, et al. The Clinical Pharmacology of Azithromycin in HIV
Positive Subjects (Pfizer): The authors analyzed azithromycin levels in
serum and leukocytes of 12 patients following administration of a 1200 mg dose.
The mean half-life was approximately 60 hours in serum and about 55 hours in
leukocytes. The peak serum level was 0.5-0.8 fg/ml, and in leukocytes the mean
was about 170 fg/ml. These results indicate that the concentration of
azithromycin in leukocytes after a 1200 mg oral dose remained above 32 fg/ml for
approximately three days, supporting the currently recommended dose of 1200 mg
weekly for MAC prophylaxis.
- Bersalona MP, et al. Genotypic Analysis of Reverse Transcriptase Coding
from Patients Treated with d4T. (St. Luke's Medical Center, Chicago): This
paper addresses the issue of d4T resistance, about which there has been little
information. The study consisted of analysis of 21 reverse transcriptase
sequences from 17 patients at different times during treatment with d4T. Three
mutations were potentially associated with d4T resistance. Only one of these
was associated with high level resistance, and this was only noted in a single
patient. This study showed that patients treated for up to 18 months with d4T
had infrequent emergence of relatively few mutations potentially associated with
d4T resistance.
- Pirzada A, et al. HIV Urine EIA: A More Sensitive Screening Test?
(St. Luke's--Roosevelt Hospital, New York): The authors evaluated the new HIV
Urine EIA test (Seradyn Sentinel Urine HIV-1 EIA) and compared it with routine
serology. Of the 142 participants, 58 (41%) were nonreactive by both tests, and
80 (56%) were positive by both tests. Two participants were initially positive
with the urine EIA, but negative with repeat testing, and both were
seronegative. One was positive with the urine test, repeatedly negative by
serology, but was serum positive for p24 antigen and HIV-1 genome by RNA and
DNA PCR. These results indicate a sensitivity of 100% and specificity of 94%.
The authors noted the ease of specimen collection, storage and testing. With
refrigeration, the EIA results remained reproducible with refrigerated urine for
periods exceeding six months.
- Valdez H, et al. Survival and Economic Impact of Cryptosporidiosis in
AIDS (Cleveland Clinic Foundation): The authors conducted a retrospective
review of 39 patients with crypto-sporidiosis. The median CD4 cell count was 30
cells/mm3. All had diarrhea, abdominal pain, and weight loss, and 25% had
biliary disease. Mean survival was 232 days, compared to 446 days in 53
controls matched for CD4 cell count. Death was ascribed to cryptosporidiosis in
26 (80%), including three due to complications of intravenous catheters placed
for therapy. The mean number of hospital days in patients with cryptosporidiosis
was 31, and the mean hospital cost was $31,712 per patient.
- Smith NH, et al. Treatment of Latent Syphilis in HIV-Infected
Persons: Ceftriaxone Versus Procaine Penicillin G plus Probenecid: Patients
with latent syphilis were randomized to receive procaine penicillin (2.4
million units IM daily) or ceftriaxone (1 gm IM daily); both groups received
parenteral treatment for 5 days/week for 15 doses. Penicillin recipients also
received probenecid, 500 mg po q6h. Results were evaluated by serologic
response. There were no clinical failures and no difference between the two
groups in terms of serologic response. The authors concluded that ceftriaxone
was at least as effective as procaine penicillin.
- Ward JW, et al. Pneumococcal Vaccination and the Incidence of
Pneumonia Among HIV-Infected Persons (CDC, Atlanta): Medical records were
reviewed for 21,334 HIV-infected patients from January 1990 through September
1995. In this group, 8,431 (40%) received Pneumovax, and 4,444 (21%) had CD4
cell counts > 200 cells/mm3. There were 276 cases of pneumococcal pneumonia
and 2,933 episodes of pneumonia with no identified pathogen. In persons with
a CD4 cell count above 200 cells/mm3, there was a 41% decrease in the rate of
pneumo-coccal pneumonia and a 25% decrease in pneumonia of unknown origin for
vaccine recipients compared to those who were not vaccinated. The authors
concluded that Pneumovax decreases the risk of pneumonia and is most effective
when given early in the course of HIV.
- Lacher M, et al. Nosocomial Bloodstream Infections in HIV-Infected
Patients--An Update (New York VA Hospital and CDC): Data were collected for
1,375 patients who had an average length of stay of 18.5 days and a mean CD4
cell count of 151 cells/mm3. Among these patients, there were 75 episodes of
primary nosocomial bacteremia, for a rate of 1.85 infections/1,000
patient-days. This rate did not change with sequential analysis. The mean
length of stay in those with bacteremia was 26.9 days. Infected central or
hemodialysis catheters accounted for 48 (64%), and peripheral venous lines
accounted for 27 (36%). The major pathogens were S. aureus (33%),
coagulase-negative staphylococci (25%), gram-negative bacilli (20%),
Enterococcus
(11%) and Candida (8%).
- Martin JN, et al. Emergence of Trimethoprim-Sulfamethoxazole Resistance
in the AIDS Era (University of California, San Francisco): Isolates of S.
aureus and Enterobacteriaceae at San Francisco General Hospital were reviewed
for the period 1988 through 1994. For E. coli and S. aureus,
there was a striking sequential increase in resistance to TMP-SMX that was more
dramatic for isolates from patients with HIV infection. For E. coli
isolates from 325 HIV-infected patients, the rate of resistance was 25% in 1988,
38% in 1991 and 72% in 1994. For 9,639 patients without HIV infection, the rate
of resistance was 12% in 1988, 16% in 1991 and 26% in 1994. For S. aureus, the
rate of resistance for 712 HIV-infected patients was zero in 1988, 1% in 1991
and 33% in 1994. For 7,559 isolates from non-HIV-infected patients, the rate of
resistance was 6% in 1994. These results demonstrate a disturbing but
predictable evolution of resistance by E. coli and S. aureus in
patients who are likely to have prolonged exposure to TMP-SMX.
- Coakley E, et al. Serum HIV-1 RNA as a Predictor of Survival in
HIV-Infected Individuals with CD4 Cell Counts < 50 cells/mm3 (Deaconess
Hospital and Harvard): The analysis consisted of 56 patients with CD4 cell
counts < 50 cells/mm3 documented between July 1989 and December 1993. Frozen
sera were analyzed by RNA PCR with follow-up outcome information through April
1996. The median CD4 cell count at baseline was 20 cells/mm3, and the median
viral burden was 200,000 copies/ml. No correlation was found between copy number
and survival; the median survival for patients with a viral burden below the
median and for those with viral burdens at baseline exceeding this value were
23 and 21 months, respectively. The CD4 cell count was more predictive of
survival than quantitative virology. These results contradict findings in
other studies that showed quantitative virology predicted survival even at low
CD4 strata.
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