MATIN AHMAD KHAN, MBBS , Ph.D
Background: : With HAART being used extensively ,transiently detectable viremia, usually 50-400 copies/ml, has been found to be a common phenomenon, occurring in about one-quarter of HIV/AIDS patients who had achieved viral suppression below the limits of quantification while remaining on the same antiretroviral regimen. Though measurable viremia may be a harbinger of drug resistance and treatment failure ,and may simply reflect variability in the assay, such as that resulting from specimen processing, or could be caused by extraneous factors, such as immunization or intercurrent illness , usually these’’ blips of viremia ‘ appear to represent no increased risk for subsequent virologic rebound. Rebound to persistent levels of viremia of 50-400 copies/ml occurred in fewer than 5% of patients, and lasting rebound viremia > 400 copies/ml, 'virologic failure,' occurred in fewer than 10%. There was no statistically significant evidence that patients who had had a previous episode of transient viremia were at a greater risk of developing persistent viremia than those who did not experience transient viremia. The characterization of this phenomenon (low viremia) in the setting of clinical practice including patients both naive and experienced to antiretroviral drugs and on both protease inhibitor (PI)-based and non-PI-based regimens in terms of long-term virologic and immunologic outcomes, are very important in the outcome of HAART ..
Aim & Objectives To examine and a disseminate- the prevalence and clinical correlates of subsequently measurable viremia from studies done on f HIV-infected patients who have achieved viral suppression below the limits of quantification (< 50 copies/ml)
Methods/Study Design : Data Source The scientific literature and eligible materials were surveyed related to the topic of ‘ Blips and its clinical correlates ‘ and was found one ‘The Centers for Disease Control and Prevention's (CDC) sponsored HIV Outpatient Study (HOPS), into which patients had been continuously recruited, to date collected data on the course of disease for more than 5500 HIV-infected, non-hospitalized patients, who have been seen in about 106 000 outpatient visits since 1992. Patients: Patients who , had atleast two consecutive HIV-1 RNA levels < 50 copies/ml (minimum, 2 months apart) that were followed by at least two more viral level determinations while remaining on the same antiretroviral therapy (ART) between January 1997 and June 2000 (median 485 days). Transiently viremic patients were defined having a subsequently measurable viremia but again achieved suppression < 50 copies/ml. Design :Non-randomized dynamic cohort study of ambulatory HIV patients in nine HIV clinics in eight cities and host of other Studies on ‘blips’
Results/Findings, : Of the 448 patients, 122 (27.2%) had transient viremia, 19 (4.2%) had lasting low-level viremia and 33 (7.4%) had lasting high-level viremia (defined as 50-400 and > 400 copies/ml, respectively). Only 16 (13.1%) of those who had transient viremia later had persistent viremia > 50 copies/ml. The occurrence of transient viremia did not vary with whether the patient was ART-naive or experienced (P = 0.31), or currently taking protease inhibitors or not (P = 0.08). On consistent ART, the median percentage increase in CD4 cell count was statistically different between subgroups of the cohort (Kruskal-Wallis, P = 0.002. )
Study Limitations (optional: The definition of a “viral blip” or transiently detected low-level viremia is evolving, but a number of working definitions have been used for research purposes. As a result, care must be taken when comparing data regarding the significance and management of blips
Conclusion : Transiently detectable viremia, usually 50-400 copies/ml, was frequent among patients who had two consecutive HIV-1 RNA levels below the limits of quantification. In this analysis, such viremia did not appear to affect the risk of developing lasting viremia. Caution is warranted before considering a regimen as 'failing' and changing medications.
