Liver fibrosis is
associated with discordance between CD4 cell counts and percentages in
HIV-positive people, according to US research published in the online edition
of Clinical Infectious Diseases. The
association was especially marked for patients with a total lymphocyte count
below 1200 cells/mm3.
believe their findings have clinical significance. “From a practical
standpoint, our findings suggest a relatively simple approach could be for
clinicians to evaluate CD percentage in addition to CD4 number whenever a
patient’s total lymphocyte count is below 1200 cells/mm3.”
Separate research also
published in the online edition of Clinical
Infectious Diseases and reported here on aidsmap.com showed that discordance between CD4 cell count and
percentage was common in patients with HIV and hepatitis C-co-infection and was
associated with important markers of liver disease.
settings, CD4 cell counts are routinely measured in HIV care. Decisions on when
to start antiretroviral therapy are partly guided by CD4 cell count and the
test is central to monitoring disease progression.
The number of CD4
cells is usually correlated with CD4 cell percentage – the proportion of lymphocyte
cells which are CD4 cells.
However, it is well
known that CD4 cell count can fall in the context of infections. Research
conducted in patients with hepatitis C mono-infection has shown that CD4 cell
count and percentage can be discordant in patients with more advanced liver
Investigators from the
US ALIVE study wanted to see if liver fibrosis was associated with discordance
between CD4 cell count and percentage.
A total of 287
people took part in the study. Their median age was 48 years, 94% were
black, 65% were men and 43% reported injecting drug use in the previous six
months. There was a high prevalence of hepatitis C-co-infection (data not
Only 47% of participants
were taking antiretroviral therapy. Median CD4 cell count was 282 cells/mm3
and median CD4 cell count percentage was 22%. An undetectable viral load was
present in 55% of patients.
Liver fibrosis was
assessed using Fibroscan. Significant
fibrosis was defined as a liver stiffness score of or above 9.3 kPa and was present
in 31% of patients.
CD4 cell count and percentage was observed in 47% of participants. Low discordance
(a lower CD4 cell percentage than would be expected for a given CD4 cell count)
was present in 19% of individuals, and 34% had high discordance (a higher CD4
cell percentage than would normally be associated with a CD4 cell count).
The risk of high
discordance was significantly increased for patients with significant fibrosis
(odds ratio [OR] = 1.69; 95% CI, 0.95-2.96). The risk was further increased
for patients with significant fibrosis and a total lymphocyte count below 1200
cells/mm3 (OR = 2.66; 95% CI, 1.11-6.40).
Low discordance was
associated with antiretroviral therapy (OR = 2.53; 95% CI, 1.27-5.06).
of immune status in HIV-infected persons is critical to assessing HIV disease
progression, for determining when to initiate therapy and for monitoring
therapeutic responses,” comment the authors. “In this study… we identified a
high degree of discordance between CD4 cell number and CD4 percentage.”
They emphasise the
association between this discordance and liver fibrosis, especially in people with a low total lymphocyte count. “These data suggest that liver
disease-related lymphopenia may contribute to CD4 number/percentage
The authors conclude,
“Clinicians may need to consider incorporating CD4 percentage into the
decision-making process of providing appropriate care to HIV-infected patients
with underlying liver fibrosis.”