-
[show abstract]
[hide abstract]
ABSTRACT: Numerous studies suggest that herpes simplex virus type 2 (HSV-2) increases the risk of HIV-1 infection but recent clinical trials of HSV-2 suppressive therapy failed to show an effect. We assessed the putative association between HSV-2 and HIV-1 in a population of HIV-concordant-negative, HIV-1-discordant and HIV-1-concordant-positive married couples from Dakar, Senegal. In agreement with previous studies, we observed a strong overall association between HSV-2 and HIV-1 (odds ratio 4.61; P < 0.001). However, this association was mainly determined by a low HSV-2 prevalence in HIV-concordant-negative couples compared with HIV-1-discordant and HIV-1-concordant-positive couples (23% versus 59% and 66%, respectively; P < 0.001). We observed no further differences in HSV-2 prevalence between HIV-1-discordant and HIV-1-concordant-positive couples (59% and 66%, respectively; P = 0.483). Neither the index (59% versus 62%, P = 1.000) nor recipient partners (41% versus 63%, P = 0.131) in HIV-1-discordant and HIV-1-concordant-positive couples showed significant differences in HSV-2 prevalence. HSV-2 does not constitute a clear risk factor for HIV-1 infection in this population.
International Journal of STD & AIDS 11/2012; 23(11):810-4. · 1.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: BACKGROUND: CD4 T-cell enumeration (CD4 count) is used as a criterion to initiate antiretroviral therapy (ART) in HIV patients and to monitor treatment efficacy. However, simple, affordable, and reliable point-of-care (POC) instruments adapted to resource-limited settings are still lacking. The PIMA CD4 analyzer is a new POC instrument for CD4 counting that uses disposable cartridges and a battery-powered analyzer. METHODS: Whole blood samples were taken by venipuncture or by finger prick from 300 subjects, including HIV-infected patients and HIV (-) controls. CD4 counts were measured by PIMA (using venous or capillary blood) and by FACSCount (using venous blood) considered as the reference. RESULTS: Similar CD4 counts were obtained by PIMA and FACSCount using either HIV+ venous blood or HIV+ finger-prick blood samples. However, with a concordance coefficient of 0.88 and a Pearson correlation of 0.89, finger-prick blood performed not as good as venous blood (0.97 and 0.98, respectively). For a clinical decision to start ART at 200 CD4 cells per microliter, sensitivity of PIMA was 90%/91% and specificity 98%/96% for venous/finger-prick blood, respectively, and for a treatment threshold of 350 CD4 cells per microliter, the sensitivity was 98%/91% and the specificity was 79%/80% for venous/finger-prick blood, respectively. Repeatability (precision) on venous blood resulted in a coefficient of variation of 4%. Using finger-prick blood, the average instrument error frequency resulting in aborted analyses was 14%. CONCLUSIONS: PIMA is a good POC instrument for screening adult HIV-infected patients in resource-limited settings for treatment eligibility. Its performance on finger-prick blood is not as good as on venous blood. Adequate training for correct use of finger-prick blood samples is mandatory
J.Acquir.Immune.Defic.Syndr. 12/2011; 58(4).
-
T.N. Dieye,
P.A. Diaw,
G. Daneau,
D. Wade,
Niang M. Sylla,
M. Camara,
A.A. Diallo,
Kane C. Toure,
Ndiaye H. Diop,
B. Mbengue,
A. Dieye,
L. Kestens,
S. Mboup
[show abstract]
[hide abstract]
ABSTRACT: Laboratory follow-up of HIV patients in resource-limited settings requires appropriate instruments for CD4 T cell enumeration. In this study, we evaluated the application of a simplified, mobile and robust flow cytometry system, the Apogee Auto 40 analyzer (Auto40) using thermoresistant reagents, for CD4 T cell enumeration. We measured the absolute CD4 counts in fresh whole blood samples from 170 Senegalese subjects, including 129 HIV-positive (HIV+) patients and 41 HIV-negative (HIV-) controls. Based on volumetric primary CD4 gating, cells were stained with commercially available reagents (Easy MoAb CD4;Bio-D, Valenzano, Italy) and analyzed on the Auto40. The results were compared with those from the FACSCount system (Becton Dickinson, San Jose, USA). Repeatability analysis was performed on duplicate testing of 49 samples on both FACSCount and Auto40. The intra-run precision was measured by 10 replicates using 3 clinical blood samples with low, intermediate and high CD4 concentrations. The results from the two instruments were in good agreement. The percent similarity between the results of both instruments was 99%+/-relative standard deviation of 12.7%. The concordance correlation coefficient was 0.99. The absolute bias and limits of agreement (LOA) between the two instruments, calculated by Bland-Altman analysis, were clinically acceptable (bias: +4 cells/mul; LOA: -111 to +120 cells/mul). The clinical agreement between the two instruments at a cutoff of 200 CD4 cells/mul was 94%. The repeatability of measurements on the Auto40 was also similar to that observed with FACSCount system (bias +0.1 cells/mul, coefficient of variation 2.5% vs bias -1.1cells/mul, coefficient of variation 2.9% respectively). In conclusion, our results indicate that the Auto 40 system, using thermoresistant reagents, is suitable for CD4 T cell enumeration and will be a helpful tool to improve HIV laboratory monitoring in resource-limited settings
J.Immunol.Methods. 09/2011; 372(1-2).
-
[show abstract]
[hide abstract]
ABSTRACT: Hepatitis C virus (HCV) is an important problem of public health in the world according to its transmission mode and its pathogenesis. The risk of blood transmission has led to be the systematic screening of blood donors in the world. In Senegal no study about HCV prevalence on the general population and also has been done. The aim of our study was to determine HCV prevalence in blood donors and the rate of co-infection with hepatitis B (HCV/HBV) or with HIV infection (HCV/HIV).
This study had been done in the National Blood Transfusion Centre (CNTS) in Dakar. Two different techniques has been used for the assessment HCV: 1/ ELISA technique and 2/ Immunoblot RIBA as confirmation test.
Our study relates to 1565 blood donors recruited in CNTS during 2002. 369 of them were new blood donors with 365 females and 1200 males. The mean average was 30.5 +/- 9.5 years, ranged from 18 to 59 years. HCV ELISA test were positive in 22 plasma samples and one of them were co-infected with hepatitis B (HCV/HBV). Four out of these 22 samples have been confirmed positive to RIBA test and three of them were not determined. HCV seroprevalence were 1.4% after ELISA and 0.25% after RIBA testing. This seroprevalence were similar in male and in female and higher in new blood donors than in regular blood donors.
Our results reinforce the necessity to screen hepatitis C virus in all Senegalese blood transfusion centres.
Bulletin de la Société médicale d'Afrique noire de langue française 02/2006; 51(1):47-52.
-
T N Dieye,
P S Sow,
T Simonart,
A Guèye-Ndiaye,
S J Popper,
M L Delforge,
A Dieye,
A D Sarr,
A Crusiaux,
J P Van Vooren,
M Devleeschouwer,
P Kanki,
S Mboup,
L Diakhate,
C M Farber
[show abstract]
[hide abstract]
ABSTRACT: Twelve HIV-1-infected, nine HIV-2-infected patients and eight HIV-negative subjects were given a 40IU booster dose of tetanus toxoid (TT). Blood was collected on days 0, 7 and 30 after immunization. Changes in HIV-1 or HIV-2 RNA load were evaluated by nested PCR. TT-IgG antibody levels were quantified by ELISA. CD4 cell counts as well as activation, memory and maturation markers of T lymphocyte subsets were determined by flow cytometry. The induction of apoptosis was investigated using 7-aminoactinomycin D (AAD) and propidium iodide (PI) staining. Proliferative responses to TT and pokeweed mitogen (PWM) were determined by the level of [(3)H] thymidine incorporation. Seven and 30 days after immunization, there was no detectable increase in HIV-1 or HIV-2 plasma load. There were also no changes in CD4 cell counts, CD69, HLA-DR and memory CD45RO or naive CD45RA antigens. Immunization did not increase the spontaneous apoptosis of peripheral blood mononuclear cells (PBMCs), CD4+ and CD8+ T cells subsets neither in controls nor in HIV-infected patients. Similarly, apoptosis induced in vitro by PWM or by the specific TT recall antigen did not vary during the study period. The proliferative response to PWM and to the TT recall antigen was decreased both in HIV-1- and HIV-2-infected patients compared to HIV-negative controls. Immunization significantly increased the TT-IgG levels in healthy controls and in HIV-infected patients. However, the anti-TT-IgG response, as measured by the fold-increase index between days 0 and 30, was significantly higher in healthy controls than in HIV-1- (P=0.036) and HIV-2-infected patients (P=0.003). In conclusion, we found no deleterious immunologic or virologic effect was detected in healthy HIV-1- and HIV-2-infected individuals after antigenic challenge with a TT booster. However, the response to TT vaccination was lower in HIV-1- and in HIV-2-infected individuals than in healthy HIV-negative controls.
Vaccine 01/2002; 20(5-6):905-13. · 3.77 Impact Factor
-
The Lancet 10/2000; 356(9234):1027. · 38.28 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Increased programmed cell death (PCD) or apoptosis has been detected in the T cells of HIV-infected subjects; it is held partially responsible for the continuous loss of CD4+ T cells during the natural course of HIV infection. Highly active antiretroviral therapy (HAART) decreases the viral load and leads to an increase of CD4+ count in vivo. In this study we evaluated PCD in total peripheral blood mononuclear cells, CD8+ and CD4+ lymphocytes before and four weeks after initiation of HAART. Seven HIV-1-infected patients were investigated. Viral load was assessed by RT-polymerase chain reaction and PCD by flow cytometry using apoptosis by 7 amino actinomycin D (7AAD) and propidium iodide (PI). After four weeks of HAART, CD4+ T and CD8+ T cell levels were stable, and plasma HIV-RNA copies were significantly decreased. In four of the patients (4/7), HIV-RNA levels were reduced to undetectable levels (fewer than 400 copies per milliliter). A statistically significant reduction of apoptosis among CD4+ cells was observed (P < 0.03), though neither in the CD8+ T cell population nor in peripheral blood mononuclear cells (PBMCS). These results demonstrate the beneficial effect of HAART on apoptosis of CD4+ cells in the early treatment stage.
Biomedecine [?] Pharmacotherapy 02/2000; 54(1):16-20. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Sickle cell disease is an hereditary hemoglobinopathy syndrome which provokes deglobulization crisis and infectious complications. These infectious diseases may be due to a permanent activation of the immune system. The aim of our study was to explore alternative pathway by measuring C3 complement and the classical pathway by C4 complement. The level of immunoglobulins IgA, IgG and IgM was also measured in the subjects sera. Thirty homozygous sickle cell anemia (SS), 25 heterozygous (AS) and 34 controls subjects (AA) were recruited in the Hôpital d'Enfants Albert Royer (HEAR), Fann hospital and Centre National de Transfusion Sanguine (CNTS). Radial Immunodiffusion (RID) technics using specific antisera for C3c, C4c, IgA, IgG and IgM were used in our study. Homozygous SS proved an increase level of IgA (50%, p < 0.003) and IgG (47%, p < 0.003), unlike of IgM level. The C3c complement decrease significantly in (27%) of homozygous SS patients (p < 0.0005) unlike of C4c level. This low level of C3 and IgG in sickle cell homozygous patients can explain the higher susceptibility to infection in these patients. Normal level of C4 and low level of C3 show activation of alternative pathway. Heterozygous AS showed a normal level of C4, C3 and immunoglobulins. Our results suggests a direct involvement of the complement system in sickle cell disease and the depletion of C3 registered was a possible cause of increased susceptibility to infections in patients with homozygous sickle cell anemia.
Bulletin de la Société médicale d'Afrique noire de langue française 02/1999; 44(2):175-9.
