ESTIMATION OF SERUM ERYTHROPOIETIN LEVELS IN ANAEMIC HIV INFECTED PATIENTS IN LAGOS, NIGERIA

Abstract

Erythropoietin response to anaemia has been reported to be suboptimal in HIV
infected anaemic patients. This was a cross sectional comparative study
conducted to estimate the serum erythropoietin levels of anaemic HIV infected
subjects in Lagos. The study aimed to assess the relationship between
erythropoietin levels and degree of anaemia, CD4+ cell count and viral load of
HIV infected treatment naive subjects and to ascertain the association with
some inflammatory cytokines (such as CRP, TNF-α, IL-6) and ferritin.
Subjects and Methods
The study population consisted of a total of 120 subjects aged 18-66 years
made up of four categories of individuals which included: (1) HIV infected
treatment naive subjects who had anaemia with Hb level <10g/dL. Control
subjects (who were age and sex matched) were: (2) HIV infected non-anaemic,
(3) non-HIV infected anaemic, and (4) non-HIV infected non-anaemic
individuals. A brief general clinical history and assessment was carried out and
questionnaires were administered to each subject. Full blood count using
automated counter- Sysmex 21N; CD4+ cell count by semi-automated
cytometry- Partec flow cytometer; and viral load using Roche amplicon were
estimated. Serum erythropoietin levels using ELISA kit supplied by ALPCO
diagnostics 26G Keewaydin Drive Salem, NH 03079; serum ferritin levels; CRP
levels; TNF- α levels; and IL-6 levels were estimated using ELISA kit and
technique supplied by Assaypro (www.assaypro.com).
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Appropriateness of EPO response was determined by calculating EPO response
ratio given by value of measured EPO levels as numerator and expected EPO
level as denominator. The expected EPO level was deduced from computer
generated regressional equation when EPO levels of HIV negative anaemic
control subjects was plotted against their haemoglobin values. Ratio less than
0.8 was accepted as suboptimal response.
Results
The mean age of male HIV infected anaemic subjects (45.15 ±5.63) was
significantly higher than that of female HIV infected anaemic subjects (34.16
±7.21) (p=0.005). The mean age for male HIV infected non-anaemic subjects
(48.00 ±14.57) was also higher than that for female HIV infected non-anaemic
subjects (34.93 ±9.68) (p=0.059).
Majority (72%) of the HIV infected anaemic patients had a normocytic
hypochromic type of anaemia. There was a weak positive correlation between
serum erythropoietin levels and CD4+ cell count (r=0.075, p=0.572). There was
a significant negative correlation between serum erythropoietin levels and
haemoglobin levels (r=-0.268, p=0.003). Twenty-seven (71.05%) of the 38 HIV
infected anaemic subjects had EPO response ratio less than 0.8.
The mean serum ferritin level was higher in HIV infected anaemic subjects
(157.15 ±2.13) than in non-HIV infected anaemic subjects (71.32 ±1.03)
(p=0.000). The mean serum interleukin-6 level was higher in HIV infected
anaemic subjects (0.0082 ±0.00090) than in HIV infected non-anaemic
subjects (0.0041 ±0.00079) (p=0.003). The mean serum C-reactive protein level
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was higher in HIV infected anaemic subjects (36.09 ±4.84) than in non-HIV
infected non-anaemic (35.75 ±4.89) and non-HIV infected anaemic subjects
(32.80 ±4.77) (p=0.004 and 0.001, respectively). The mean serum tumour
necrosis factor-α level was higher in HIV infected anaemic subjects (0.071
±0.055) than other arms of the study population (p=0.000).
Conclusion
Human immunodeficiency virus infected anaemic subjects had reduced serum
erythropoietin levels. Serum Ferritin, serum CRP, serum IL-6 and serum TNF-α
levels were raised in HIV infected anaemic subjects.