ESTIMATION OF INTERLEUKIN 6, C-REACTIVE PROTEIN AND SOME HAEMATOLOGICAL INDICES AS SURROGATE MARKER FOR SEVERITY OF IMMUNODEFICIENCY IN HIV-INFECTED PATIENTS AT THE UNIVERSITY OF BENIN TEACHING HOSPITAL, BENIN CITY,EDO STATE

Abstract

HIV infection burden in Nigeria is considered to be the 2nd highest in the world. The recent dwindling support to Nigeria from multinational govemental and non-govemental organisations is bound to multiply the socioeconomic burden. CD4+ cell counts and viral load assessments are the hallmark in assessing HIV disease activity, severity of the disease and response to therapy.. However, in resource-limited settings accessibility and affordability of these technically involving investigations may prove challenging. Easily assessable and affordable investigations like FBC and ESR if validated may have some usefulness in assessing disease activity, severity and response to therapy. Understanding how disease severity, course and therapy with HAART affects parameters like IL-6, CRP, ESR and investigations like FBC may guide in making predictive and informed decision in the care of these individuals.
The objective of this study was to determine the serum interleukin 6, C-reactive protein levels and some haematological indices could serve as surrogate markers of immunodeficiency in HIVinfected individual. The study also aimed to determine the effect of disease severity using CD4+ cell counts.
A cross-sectional study conducted over a period of six (6) months, comprising of one hundred and sixty participants, divided into three groups; forty (40) HIV seronegative participants, eighty (80) HIV seropositive therapy naïve participants (further stratified into fifty-two (52) asymptomatic and twenty-eight (28) symptomatic participants), and forty (40) HIV seropositive subjects on HAART, with mean ages of 40.49 ± 11.14 years, 39.85 ± 9.96 years and 43.08 ±
10.36 years respectively, (p-value = 0.184). The seronegative group consists of 32.5% males and 67.5% females; the seropositive therapy naive group consists of 28.8% males and 71.2% females; the therapy experienced group consists of 25.0% males and 75.0% female. Full blood counts and CD4 counts were assessed using Sysmex automated counter XN-1000, Japan and flow cytometerbased assay (Cyflow SL3 Green, Germany) respectively. ESR was assessed using Westergreen method and CRP levels were assessed using immunoturbidimetric method (latex agglutination kit- Agappe Diagnostics, Switzerland). Interleukin 6 levels were assessed using ELISA test kits (Quantikine, R&D sys, Inc. USA). Data were analysed using SPSS version 21.
The mean Hb concentration and haematocrit observed in the HIV seropositive therapy naïve participants were significantly lower when compared with the means in the HIV seronegative

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participants 11.4 ± 2.2 g/dl vs. 12.6 ± 1.7 g/dl, and 34.4 ± 5.5 % vs. 37.0 ± 4.5 %, p-values 0.006 and 0.03, respectively. The mean ESR, CRP and IL-6 observed were significantly higher in the HIV seropositive therapy naïve individuals when compared with the means in the HIV seronegative participants, 71.2 ± 41.1mm/hr vs. 21.1 ± 14.3 mm/hr, 39.92 ± 27.28 mg/dl vs. 18.77 ± 17.51 mg/dl, and 21.58 ± 4.75 pg/ml vs. 19.72 ± 1.99 pg/ml, p-values <0.001, <0.001 and 0.032, respectively. The mean ESR (91.4 ± 42.0 mm/hr) and CRP (52.38 ± 29.72 mg/dl) were statistically significantly higher in the symptomatic participants when compared with the mean ESR (60.1 ± 36.6 mm/hr) and CRP (33.1 ± 23.52 mg/dl) in the asymptomatic participants (p-values 0.002 and 0.006) respectively. The mean haematocrit (31.9 ± 5.7 %) observed in the symptomatic participants was significantly lower when compared to the mean haematocrit (35.9 ± 4.9 %) in the asymptomatic participants (p-value 0.014). In the HIV seropositive participants who were therapy experienced, a significantly higher mean Hb concentration was observed when compared with that in the HIV seropositive therapy naïve participants, 12.5 ± 1.7 g/dl vs. 11.4 ± 2.2 g/dl (p-value 0.006). The mean ESR and CRP observed in the HIV seropositive therapy experienced participants were significantly lower when compared to those in the therapy naïve participants; 40.8 ± 35.3 mm/hr vs. 71.2 ± 41.1mm/hr and 27.99 ± 21.54 mg/dl vs. 39.92 ± 27.28 mg/dl (p-values <0.001 and 0.015), respectively. In all the participants recruited for this study, significant positive correlations were observed between the CD4 counts and WBC (r=0.237), TLC (r=0.548), platelet count (r=0.207), Hb concentration (r=0.31) and haematocrit (r=0.25), p-values 0.002, <0.001, 0.018, <0.001 and 0.001, respectively; there were also significant negative correlation between the CD4 counts and ESR (r=-0.447), CRP (-0.368) and IL-6 (-0.15), p-values <0.001, <0.001 and 0.048, respectively.
This study revealed that the evaluation of clinical features of individuals with HIV infection and parameters like Hb concentration, haematocrit level and ESR may guide in the assessment of disease activity, severity and response to therapy. The study also showed that worsening HIV infection is associated with significantly higher levels of inflammatory markers- ESR, CRP and IL-6; and that therapy with HAART is associated with significantly higher Hb concentration and significantly lower ESR and CRP levels. These finding are in keeping with those of existing literatures.