Division of Infectious Diseases

Ajay Bharti, MD

Ajay Bharti, MD
Assistant Adjunct Professor of Medicine

220 Dickinson

San Diego, CA 92103-8208

Email: abharti@ucsd.edu

Phone: 619-543-8091


Background

Dr. Bharti obtained his medical training from the Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India. He completed Internal Medicine residency at the Mercy Hospital of Pittsburgh, Pennsylvania and Infectious Diseases fellowship at the University of Texas Medical Branch at Galveston, Texas. Pursuing his interest in clinical and translational research, he did a NeuroAIDS fellowship at the University of California San Diego (UCSD) HIV Neurobehavioral Research Program (HNRP). He currently has a R01 grant from the National Institute on Drug Abuse to study the impact of HCV treatment on brain function. He sees patients at his weekly infectious diseases clinic and on the inpatient consultation service.

Research

Clinical

Teaching

Selected Publications

i. Detecting co-infections using sensitive and cost-saving strategies

Detection of co-infections such as malaria among people living with HIV in resource-limited settings is hampered by low sensitivity of the commonly used microscopy method. We demonstrated that stored serum samples up to 2.5 years old have detectable parasite DNA by polymerase chain reaction (PCR) based assays. This finding has the potential for the retrospective identification of malaria parasitemia in patient cohorts to determine potential interactions of malaria and other diseases such as HIV. PCR based assays, although highly sensitive, are expensive for use in resource-limited settings. To address this issue, we adapted a pooling platform that can reduce the number of assays needed to detect malaria infection. We demonstrated for the first time that PCR-based assays using pooling platforms are sensitive and efficient in detecting malaria infection. This strategy is not limited to malaria and can be adapted for use in a wide range of infections such as CMV, HCV, and HBV.

  1. Bharti AR, Kailash P. Patra, Chuquiyauri R, et al. PCR Detection of Plasmodium vivax and Plasmodium falciparum DNA from stored serum samples: Implications for retrospective diagnosis of malaria. Am J Trop Med Hyg 2007:77(3):444-446. [PMID: 17827357]
  2. Bharti, AR, Letendre, SL, Patra KP et al. Malaria diagnosis by a polymerase chain reaction-based assay using a pooling strategy. Am J Trop Med Hyg 2009:81(5):754-757. [PMID: 19861605 PMCID: PMC2770880]

ii. Determining the prevalence and risk factors associated with co-infections in people living with HIV (PLWH)

Co-infections such as malaria and hepatitis C virus (HCV) infection in PLWH can adversely impact the outcome of both the co-infection as well as HIV. However, the accurate data on the burden of co-infections is limited by lack of resources (as in malaria) or lack of sensitivity of screening assays (as in HCV). We conducted, for the first time, to determine malaria co-infection among PLWH in southern India using the pooling strategy mentioned earlier. We found that there was a considerable burden of malaria co-infection (9.8%) in this cohort and that it was predominantly due to Plasmodium vivax (60%); the rate of Plasmodium falciparum infection was more than 6-fold higher compared with the general population; and individuals co-infected with malaria and HIV were not more likely to be immunosuppressed than individuals with HIV infection alone. These findings refuted the notion that malaria co-infection among PLWH in India is not a problem and will help direct resources towards tackling the problem. Although the HCV antibody test is adequate for screening HIV uninfected individuals, its false negative rate is higher in PLWH. We found that the rate of seronegative HCV (SN-HCV) in our cohort was 13%. We proposed a composite risk score using readily available clinical variables that correctly identified seronegative HCV with sensitivity up to 85% and specificity up to 88%. This strategy can be used in the clinical setting for screening individuals at the highest risk of SN-HCV.

  1. Bharti AR, Saravanan S, Madhavan V, Smith DM et al. Correlates of HIV and malaria co-infection in Southern India. Malar J 2012, 11:306. [PMID: 22943054 PMCID: PMC3504568]
  2. Bharti, AR, Letendre, SL, Wolfson, T et al. Clinical variables identify seronegative HCV co-infection in HIV-infected individuals. J Clin Virol 2011;52(4):328-32. [PMID: 21924674 PMCID: PMC3217127]

iii. Investigating the mechanism in HIV-associated effect on brain function

Neurocognitive impairment (NCI) is common among PLWH but no biomarkers have been sufficiently validated for diagnosis and prognosis of NCI in the clinic. Our efforts have been directed towards addressing limitations of biomarkers of neurocognitive complications of HIV disease. We identified a combination of 3 biomarkers (sCD14, MCP-1, SDF-1α) of worsening or improvement that correctly classified all patients who will remain neurocognitively stable (either stably normal or stably impaired). This has clinical value since assessment and intervention efforts can then be focused on those who are less likely to remain stable. We also investigated whether inflammation-associated biomarkers are associated with cerebral injury on proton magnetic resonance spectroscopy in chronically HIV-infected subjects. We found that markers of inflammation and immune activation, in particular MCP-1 and sCD14, predominantly reflecting CNS sources, contribute to the persistence of brain injury in a metabolite and region-dependent manner in chronically HIV-infected patients on stable combination antiretroviral therapy.

  1. Marcotte TD, Deutsch R, Michael BD......Bharti AR, Grant I, and Letendre S. A Concise Panel of Biomarkers Identifies Neurocognitive Functioning Changes in HIV-Infected Individuals. J Neuroimmune Pharmacol. 2013;8(5):1123-1135. [PMID: 24101401 PMCID: PMC3874146]
  2. Anderson AM, Harezlak J, Bharti A, et al. Plasma and cerebrospinal fluid biomarkers predict cerebral injury in HIV-infected individuals on stable combination antiretroviral therapy. J Acquir Immune Defic Syndr. 2015;69(1):29-35. [PMID: 25622053 PMCID: PMC4424074]
  3. Bharti AR, Woods SP....Letendre SL. Fibroblast Growth Factors in Cerebrospinal Fluid are Associated with HIV Disease, Methamphetamine Use, and Neurocognitive Functioning. HIV AIDS (Auckl) 2016; 8:93-9. [PMID: 27199571 PMCID: PMC4857802]