Page 221 - HIVMED_v21_i1.indb

Page 3 of 9 Original Research

irrespective of their treatment regimens, immunological or A normality test (D’Agostino & Pearson normality test) was
virological parameters. Informed consent was obtained from applied to the data set, and all continuous variables
the study participants and the controls. Patients were (including the CD4+ T-cell count) were expressed as a
excluded only if they refused or were otherwise unable to median and interquartile range. Comparisons between pre-
give consent. and post-dialysis parameters were performed using a paired
student’s t test.
The study participants were recruited from both the public
and private sector including the Helen Joseph Hospital The longitudinal trend analysis of the absolute CD4 counts,
(Johannesburg, South Africa), the Chris Hani Baragwanath the percentage of CD4 cells and the viral loads were analysed
Hospital (Johannesburg, South Africa), the Charlotte using a time series where possible.
Maxeke Johannesburg Academic Hospital (Johannesburg,
South Africa) and the Donald Gordon Medical Centre All the statistical data were analysed using Graph Pad Prism
(Johannesburg, South Africa). 7.05. A p-value of < 0.05 was considered significant for these
analyses.
Demographic and clinical information were collected,
including the presence of comorbid diseases, drug history, Ethical consideration
social habits, the presence of chronic infections, the Ethical approval was obtained from the Human Research
underlying cause for ESKD and the ART regimen. All Ethics Committee of the University of the Witwatersrand
available (14 of 17 participants) CD4+ T-cell counts and HIV (reference number: M170858).
viral loads were documented.
Results
Prior to taking blood samples, the study participants were
matched 1:1 with HIV-uninfected patients having ESKD A total of 17 participants and 17 controls were included in
receiving chronic haemodialysis. The control group was this study. The controls were matched for age, sex and BMI to
selected at each site where the study participants were the participants. All the study participants were diagnosed
selected. Controls were selected based on the criteria needed with ESKD and were receiving RRT by means of chronic
to match them with the HIV-infected group. They were haemodialysis (three sessions per week, and each session
matched with the HIV-infected group for age, sex and body lasting ~4 hours).
mass index (BMI).
Renal biopsies had not been performed in most participants
Vascular access was established immediately prior to (2 of 17; 11%); and in the majority of cases (15 of 17; 88%), the
haemodialysis. Peripheral whole blood samples were cause of renal failure was inferred from the patient’s medical
collected with a needle and a syringe and placed in a 4.5 mL records. The most common cause for ESKD was stated as
EDTA tube. Haemodialysis was initiated and continued hypertension (82%). Most of the study participants had
for 4 hours. A second whole blood sample was collected uncontrolled hypertension. Two patients had (renal biopsy
with a needle and syringe within 10 min after the end of confirmed) HIV-associated nephropathy (2%) and one patient
dialysis and placed in a 4.5 mL EDTA tube. The samples had renal failure as a result of ethylene glycol overdose (1%).
were transported at room temperature to the laboratory
within 24 h of collection. All HIV-infected patients were treated with first-line ART
regimen at doses adjusted for kidney failure. All HIV-infected
All CD4+ T-cell counts were analysed by flow cytometry. participants had received a GeneXpert (Cepheid, Sunnyvale)
Briefly, 100 µL of whole blood was incubated for 10 min test for Mycobacterium tuberculosis prior to the commencement
in an automated T-Q-Prep machine (Beckman Coulter, of haemodialysis. Only a single patient had hepatitis B virus
Berea, CA, USA) with 5 µL Cyto stat tetra CHROMETM co-infection. The socio-demographic details are summarised
CD45 (fluorescein isothiocyanate (FITC))/CD4(RD1)/ in Table 2.
CD8(ECD)/CD3 (PC-5) monoclonal antibody (Beckman
Coulter Ireland Inc). During the incubation period, a Leucocyte count and T-cell subsets were measured
stabiliser, lysing agent and fixative were added. Flow count immediately before and after a single session of haemodialysis
beads of 100 µL (Beckman Coulter) were then added to the for the study controls and the study participants. These
lysate and analysed on a Beckman-Coulter FC500-MPL flow results are summarised in Tables 3 and 4.
cytometer on a 4-colour T-cell protocol. Absolute T-cell
numbers were then calculated using the total white cell count For the HIV-uninfected study controls, the following pre-
(WCC), and the percentage of lymphocytes and the dialysis parameters were less than the normal reference
percentage of CD3 or CD4 or CD8 cells were also calculated ranges: total leucocyte count (5.9%), absolute CD4+ T-cell
and expressed as both an absolute number (cells/µL) and a count (29%) and the absolute CD8+ T-cell count (23%). In
percentage of WCC. The CD4+ T-cell count was compared addition, the following post-dialysis parameters were less
18
using the laboratory-determined reference range. In four than the normal reference ranges used: absolute CD4+
study participants, only CD4+ T-cell counts could be T-cell count (23%) and the absolute CD8+ T-cell count
performed. (38%; Table 3).

http://www.sajhivmed.org.za 213 Open Access