BLOOD AND CEREBROSPINAL FLUID HIV LOAD INPATIENTS WITH HIV-ASSOCIATED NEUROLOGICAL DISORDERS
Authors: Boiko Yu.I. , Moskaliuk V.D. 
Published: December 2022

Relevance. The issues of replication and concentration of the human immunodeficiency virus (HIV) in various tissues and body fluids remain insufficiently studied. Solving this problem is hindered by the lack of simple, cheap and accessible methods for quantitative determination of HIV in various tissue samples.
Objective is to establish a relationship between the presence of HIV-associated damage of the central nervous system (CNS), the number of CD4+ lymphocytes in the blood, and the level of HIV load in blood plasma and cerebrospinal fluid. The difference between the level of HIV viral load in different tissues and biological fluids may reflect the formation of several independent reservoirs of HIV replication in the human body.
Materials and methods. 87 patients with HIV infection with clinical signs of central nervous system damage who had no experience of taking antiretroviral drugs (ARVP) were examined. Paired samples of blood and cerebrospinal fluid were analyzed to determine the level of viral load in both biological fluids, as well as the number of CD4+ lymphocytes in the blood.
Results. It was established that the patient's presence of clinical signs of CNS damage was reliably correlated with the level of HIV load in the cerebrospinal fluid (logistic regression, P<0.001) and was not associated with the content of CD4+ lymphocytes or the level of HIV load in the blood (logistic regression, P >0.05).
The level of HIV load in the cerebrospinal fluid (CSF) was on average 1.5 lg RNA copies/ml higher (P<0.001) in patients with neurological disorders despite the fact that the mean CD4+-lymphocyte count and HIV load in blood in both groups of patients did not differ. The difference between the HIV load in blood and cerebrospinal fluid of patients with neurological disorders was only 0.8 lg RNA copies/ml.
Despite the similar indicators of the content of CD4+ lymphocytes and the amount of HIV in the blood, in HIV-infected patients with clinical signs of CNS damage, the level of HIV load in CSF is 1.5 lg RNA copies/ml higher, compared with patients without symptoms of CNS dysfunction (P <0.001). The difference between HIV load in blood and cerebrospinal fluid in the presence of neurocognitive disorders was reduced to 0.7 lg RNA copies/ml compared to 1.8 lg RNA copies/ml in the group of individuals without signs of CNS damage. The presence of HIV-associated damage to the central nervous system is not statistically related to the content of CD4+ lymphocytes or the level of HIV load in the blood.
Statistical analysis showed that a CSF HIV load equal to or greater than 4.00 lg RNA copies/mL (10,000 RNA copies/mL) indicated a significant likelihood of HIV-associated CNS involvement in patients (P<0.001) .
Conclusion. The method of determining the level of HIV load in cerebrospinal fluid samples can be used to optimize the diagnostic algorithm of HIV-associated lesions of the central nervous system, differential diagnosis with neurocognitive disorders of non-infectious etiology. The threshold for making a clinical decision is the level of HIV load in the CSF sample, which is equal to or exceeds 4.00 lg RNA copies/ml, which indicates a significant probability of the presence of an HIV-associated lesion of the CNS in the patient.