Zafer Habip

Neopterin and Soluble CD14 Levels as Indicators of Immune Activation in Cases with Indeterminate Pattern and True Positive HIV-1 Infection

Background We aimed to evaluate the roles of the plasma immune activation biomarkers neopterin and soluble CD14 (sCD14) in the indirect assessment of the immune activation status of patients with the indeterminate HIV-1 (IHIV-1) pattern and a true HIV-1-positive infection (PCG). Methods This cross-sectional and descriptive study included eighty-eight patients with the IHIV-1 pattern, 100 patients in the PCG, and 100 people in a healthy control group (HCG). Neopterin and sCD14 levels were determined by competitive and sandwich ELISA methods, respectively. Results Mean neopterin and sCD14 levels among those with the IHIV-1 pattern were significantly lower than among the PCG (p < 0.001 and p = 0.001, respectively), but they were similiar to those in the HCG (p = 0.57 and p = 0.66, respectively. Mean neopterin and sCD14 levels among the PCG were found to be significantly higher than among those with the IHIV-1 pattern (p < 0.001 and p = 0.001, respectively) and among those in the HCG (p = 0.001, p < 0.001, respectively). Neopterin did not have adequate predictive value for identifying those in the PCG (area under the curve [AUC] = 0.534; 95% CI, 0.463–0.605; p = 0.4256); sCD14 also had poor predictive value but high specificity (100%) for identifying those in the PCG (AUC = 0.627; 95% CI, 0.556–0.694; p = 0.0036). Conclusions While low levels of these two biomarkers were detected among those with the IHIV-1 pattern, they were found in high levels among those in the PCG. These two markers obviously cannot be used as a sceening test because they have low sensitivies. Taken together, we suggest that neopterin and sCD14 may be helpful because they both have high specificity (92%-100%) as indirect non-specific markers for predicting the immune activation status of individuals, whether or not they have true positive HIV-1.

Problems encountered in conventional HIV 1/2 Algorithms: lack of necessity for immunoblot assays to confirm repeated ELISA reactive results

Background The use of conventional (serologically based) HIV 1/2 diagnostic algorithms has become controversial in recent years. Objectives Sera from patients who underwent verification tests were evaluated because repeated ELISA-reactive results demonstrated a HIV1+HIV2 positive band pattern. Methods The line immunoassay (LIA) test was used for repeated HIV enzyme immunoassays (EIA)-reactive sera in patients at three centers. The Bio-Rad Geenius™ HIV 1/2 and the HIV-1 RNA tests were used. HIV-1 and RNA HIV-2 were investigated using PCR. Results LIA was used to evaluate 3,224 out of 10,591 samples with repeated ELISA reactivity (30%). We found that 32 (1%) of the sera, along with HIV1 bands and HIV2 gp36 bands, were positive. Only 28 of the 32 verified serum samples with gp36 bands were repeated, and no gp36 band positivity was detected using the Bio-Rad Geenius™ HIV-1/2 confirmatory assay in these serum samples. The HIV-2 proviral DNAs were also negative. Therefore, we excluded the possibility of HIV1+2 co-infection. All samples from the 32 patients were positive for HIV-1 RNA. Conclusion Our findings highlight the need to exclude confirmatory tests like the LIA test from the current diagnostic HIV algorithm and replace it with rapid HIV-1 and HIV-2 confirmatory immunochromotographic tests.

Neopterin and soluble CD14 levels as indicators of immune activation in cases with low anti-HCV reactivity and true HCV infection

Neopterin and soluble CD14 (sCD14) are detected at high levels in hepatitis C virus (HCV) infections. We aimed to evaluate the role of these plasma immune activation biomarkers, for the indirect assessment of immune activation status of patients with low anti-HCV reactivity and a HCV infection. Low anti-HCV reactivity group (LRG, n: 70), true positive HCV infection group (THG, 30) and healthy control group (HCG, 30) were analyzed in this study. We have used ELISA, HCV RIBA/LIA and HCV-RNA methods. Mean neopterin levels were significantly lower in LRG than THG (p <0.001). In contrast, those values were not significantly different from those of HCG (p >0.05). Mean sCD14 were significantly higher in LRG than THG and HCG (p <0.05, p <0.001). Values of 3.95 μg/ml and 5.36 nmol/l for sCD14 and neopterin resulted in the maximum area under the receiver operating characteristic curves (ROC), which were 0.859 (95% CI, 0.745 to 0.935; <0.0001) and 0.788 (95% CI, 0.663 to 0.883; <0.0001), respectively. These cut-offs corresponded to a sensitivity of 73.3% and a specificity of 73.3% for neopterin and of 100% and 76.7% for sCD14. Our results suggest that a specific immunoactivation might be caused by true positive HCV infection. Due to the significant results sCD14 in LRG might be non-specifically affected by some underlying atypical immunohematological pathologies. Only neopterin might be used to exclude low anti-HCV reactivity from a true HCV infection. The use of neopterin but not sCD14 in combination with fourth-generation EIA/CMIA combo tests will be useful when nucleic acid tests are not available for screening blood donors at blood banks.

Serum Neopterin and Procalcitonin Levels in Relationship with Pediatric Burn Wound Infections

Infection and septic complications in burn patients can be monitored by procalcitonin (PCT) and neopterin plasma values. The aim of the study was to investigate serum neopterin and PCT levels with WBC (white blood cell) and CRP (C-reactive protein) levels in patient group (PG) and healthy control group (HCG) and to investigate the relationship of these markers with burn wound infections (BWI). As the PG, 23 patients between 0-12 ages and up to 30% Total Body Surface Area (TBSA) burned and 15 HCG were included. PCT, neopterin, WBC, and CRP results on the first, the seventh, the fourteenth and the 21st day have been compared. During the follow-up period, 11 patients with BWI and 12 patients without BWI were classified as infected and non-infected patients, respectively. PCT and neopterin levels were detected higher in patients with BWI but no significant difference were present. Also, PCT and neopterin levels within the first 24 hours following the burn were detected higher in PG than HCG. CRP and WBC levels were detected high due to burn trauma. PCT and neopterin levels were increased in patients with BWI. PCT levels were increased during the pre-infectious period, while neopterin levels increased during the post-infectious period.