Abstract Book Vol. 1 [International Conference on AIDS (16th: 2006: Toronto, Canada)]

end with the NucliSens EasyQ HIV-1 assay offers state-of-the-art viral load
measurements.
Methods: Nucleic acids from well-characterized analytical and subtype panels
were isolated using the NucliSens miniMAG and easyMAG systems. HIV-1 RNA
was amplified using the NucliSens EasyQ HIV-1 assay and amplicon formation
was monitored using the NucliSens EasyQ Analyzer. Assay performance was
assessed by the statistical analyses of detection limit, quantitative range,
subtype detection and diagnostic specificity.
Results: Analyses of an analytical panel based on International Units (IU)
with NucliSens EasyQ HIV-1 in combination with magnetic extraction as frontend demonstrated accurate HIV-1 viral load monitoring over a range of 161
- 3x106 IU/mi with a detection limit of 73 IU/ml. Analyses of FDA and BBI
HIV-1 subtype panels showed successful detection of subtypes A through J and
linearity was confirmed. Analyses of 114 HIV-1 negative donor plasma samples
demonstrated a 100% diagnostic specificity.
Conclusions: The combination of NucliSens miniMAG or easyMAG magnetic
extraction with NucliSens EasyQ HIV-1 real-time viral load determination
showed to be efficient and reliable. HIV-1 viral load monitoring is subtype
independent and quantitative over a broad range. While NucliSens miniMAG
extraction provides a cost efficient solution for low or medium throughput
laboratories, NucliSens easyMAG extraction is optimally suited for high volume
labs by offering high throughput and high level of user convenience.
MOPE0150
Evaluation of dried blood spots (DBS) for HIV-1
antibody testing in Ethiopia
D. Kassa, D. Tessema, H. Melese, T. Messele, W. Tamene, Z. Ahmedin,
M. Tebeje, A. Adane, N. Gezahegn, D. Wolday. Ethiopian Health and Nuitrion
Reserch Institute, Addis Ababa, Ethiopia
Background: Seroepidemiological survey has been conducted in Ethiopia
to assess the prevalence of HIV. However, as serosurvey is logistically very
challenging DBS has been considered as better alternative as it is easy to
transport, tolerant of high temperature and antibodies are more stable DBS.
We aimed to assess the performance of DBS technology vs. plasma based
EIA.
Methods: 714 Paired plasma and DBS were collected from four sites. All
specimens were tested in parallel with Vironostika-HIV Uniform II plus O0
(ELISA-1), Vironostika-HIV Uniform II Ag/Ab (ELISA-2) and Enzygnost HIV1/2. Discrepant results between plasma and DBS were tested with WB.
Results: HIV positive of the plasma samples was 22.4%, 23.7% and 15.0%
with ELISA-1, ELISA-2 and Enzygnost respectively. Out of the positive plasma
samples with ELISA-1 and ELISA-2, Enzygnost had missed 14.3% and 14.2%
respectively. Comparing DBS and plasma test results, there was a 100%
concordance in the negative HIV test results in all three ELISAs. However, out
of the total confirmed plasma HIV positive specimens with ELISA-1 (n=126),
ELISA-2 (n=127) and Enzygnost (n=107), 14.3%, 14.2% and 0.9% DBS
specimens were found to be negative respectively, giving an overall discrepancy
of 14.3%. Indeterminate test results by WB of the specimens with discrepant
plasma/DBS test results were excluded from concordance analysis.
Conclusions: Our results showed DBS underestimated positive results mainly
at low OD level which could be due to the low blood volume in the spot or
other reasons. Although DBS is an alternative candidate for serosurvey, we
suggest that further optimization of the assay should be undertaken. However,
the highest concordance between DBS and plasma in the positive specimens
in Enzygnost HIV-1/2 was due to the characteristic of the assay which missed
most positive of DBS as well as plasma with relatively low OD values.
MOPE0151
Sensitivity of total lymphocyte count as a predictor
of CD4 count in ARV naive HIV patients at JUTH, Jos,
Nigeria
M. Akanbil, T. Babafemi2, L. Welty2, J. Idoko3, I. Samson3, N. Gwamzhi3,
R. Murphy2. 1Department of Medicine, JUTH/ APIN. Jos Nigeria, Internal
Medicine, Jos, Nigeria, 2North Western University, Feinberg School of
Medicine., Infectious Diseases, Chicago, United States, 'Department of
Medicine, JUTH/ APIN. Jos Nigeria, Infectious Diseases, Jos, Nigeria
Background: The WHO recommends that in settings where CD4 enumeration
cannot be performed, ART should be initiated for WHO clinical stage 2 or 3 if
total lymphocyte count (TLC) is < 1200 cells/mm3. The proposed guideline
change for 2005-2006 is to apply the TLC <1200 cut-off to WHO stage 2
disease only. We compared entry CD4 count and TLC among treatment-naive
WHO stage 2 patients in Jos, Nigeria.
Methods: Data were obtained from the records of 3,462 pre-consented HIVseropositive patients attending the APIN clinic, JUTH, Jos between January
2004 and December 2005. HIV was confirmed using western blot. CD4 was
analyzed using flow cytometry, and complete blood count by an auto-analyzer.
Total lymphocyte count was calculated from the complete blood count. Results

were analyzed using statistical software package R, 2.1.1
Results: The CD4 and TLC counts of 1281 patients with WHO stage 2
disease were analyzed. CD4 and TLC were significantly positively correlated
(Spearman's rho = 0.48, p < 0.001). Using TLC < 1200 as a predictor of
CD4 < 200 resulted in 31.5% sensitivity, 96.0% specificity, 95.9% positive
predictive value, and 31.6% negative predictive value. Increasing the cutoff
value to 1900 resulted in 67.0% sensitivity, 67.9% specificity, 86.3% positive
predictive value, and 40.4% negative predictive value. Both TLC and CD4 were
highly skewed. Median TLC was 1200 (IQR = 1118, min = 180, max = 8190)

and median CD4 was 108 (IQR = 154, min = 1, max = 790). There were no
statistically significant differences in TLC or CD4 by gender.
Conclusions: In these WHO stage 2 patients from a resource-limited setting,
TLC <1200 cell/mm3 was a poor predictor of CD4 count < 200 cells/mm3.
Over half of patients with CD4 count < 200 would have been inappropriately
excluded by TLC-guided treatment with a cut-off of 1200.
MOPE0152
Antibiotic susceptibility patterns of bacterial
opportunistic respiratory pathogens in HIV/AIDS
patients in Lagos, Nigeria
N. Idika1, M. Aniedebe2. 'Nigerian Institute of Medical Research, Microbilogy,
Yaba, Nigeria, 2Nigerian Institute of Medical Research, Yaba, Human Virology,
Lagos, Nigeria
Background: Approximately 40 million persons live with HIV infections
worldwide while the prevalence is 5% in Nigeria. The main biological
characteristic of HIV is the progressive breakdown of cellular immunity causing
multiple pathological conditions that lead to opportunistic infections. They
could be viral, bacterial, fungal or parasitic and are the most common causes
of death in HIV/AIDS patients.
Antimicrobial drug use has been reported to be a major contributor to the
emergence of resistance in respiratory pathogens which vary depending on the
rates of antimicrobial drug use.This study therefore was designed to investigate
resistance of bacterial opportunistic respiratory pathogens in order to provide
information for better management of HIV/AIDS in Nigeria.
Methods: A total of 310 sputum samples from HIV patients with respiratory
infections reporting at 3 anti-retroviral (A R V) clinics in Lagos, were tested and
the isolates identified using standard microbiological methods. The antibiotic
susceptibility patterns were determined using agar diffusion method.
Results: The nature and frequency of the pathogens obtained were
Morexella catarrhalis (25.1%), Staphylococcus aureus (9.2%), Streptococcus
pneumoniae (8.3%) Pseudomonas aeruginosa (7.3%) and coaggulase negative
Staphylococcus (6.6%).Other pathogens including some Enterobacteriacae
were obtained in low percentages. Ofloxacin was the most effective antibiotic
(86.8%) in this study followed by ciprofloxacin (80.2%), gentamycin
(70.8%), augmentin (58%), tetracycline (27.2%), cotrimoxazole (12.8%) and
erythromycin (10.7%).
Conclusions: The results have shown that normal bacterial flora of the sputum
and Enterobacteriacae have the potentials for respiratory infections in HIV
infections. The antibiotic patterns obtained will aid the management of HIV
in Nigeria.
MOPE0153
HIV rapid testing for scaling up HIV prevention
efforts
A. Sands', G. Vercauteren', G. Beelaert2, K. Fransen2. 'World Health
Organization, Essential Health Technologies, Geneva, Switzerland, 'Institute
of Tropical Medicine, Microbiology, Antwerp, Belgium
Background: A necessary component in efforts to achieve the goal of Universal
Access to HIV prevention, treatment and care programmes for all by 2010 is
the provision of reliable and accurate HIV testing. With increased availability of
lesser-complexity HIV rapid tests, the quality and performance of these tests
must be assessed prior to implementation in resource-limited settings.
Methods: A variety of HIV rapid tests from different manufacturers were
evaluated by WHO using a panel of 769 HIV positive and negative clinical
specimens. Common false positive and false negative results were observed
and recorded. In addition, 9 commercially acquired HIV panels were used to
assess sensitivity in seroconversion and mixed titers of anti-HIV. Other factors
assessed included storage conditions, ease of use, inter-reader variability.
Results: The observed HIV rapid test performance characteristics included
sensitivity (ranging 99.6% -100%), specificity (ranging 98.8%-100%) and
inter-reader variability (as assessed by 3 independent readers) ranging 0%4.6%. Common false reactivities were observed between test kits using similar
antigen preparations. The seroconversion indices on the 8 seroconversion
panels ranged from 1.625 (specimens) later to equal the bench mark assay. All
tests were able to identify all specimens in the mixed titer panels. The shelf life
of the rapid tests ranged 6-24 months and 13 of the test kits could be stored
between 20-300C. Most of the rapid tests took no more than two steps to be
completed.
Conclusions: A total of 19 HIV rapid tests have been evaluated by WHO and
were comparable in performance to commonly available enzyme immunoassays
(EIAs). The simpler rapid test procedure (relative to EIAs) means that they
can be used outside the traditional laboratory settings. It is imperative that
provision be made for independent evaluations of HIV rapid tests in the setting
of intended use.

Monday
14 August
Poster
Exhibition ---- - - - -------

XVI INTERNATIONAL AIDS CONFERENCE * 13-18 AUGUST 2006 * TORONTO CANADA * ABSTRACT BOOK VOLUME 1