Transplant Molecular Diagnostics Lab

Most of our tests incorporate quantitative real-time PCR technology that rapidly links amplification with detection and quantification of viral DNA. Antiviral therapy is instituted upon viral DNA detection, followed by close monitoring of quantitative viral titers to assess and maintain the balance between immunosuppression and anti-infective therapies.

Currently, our real-time PCR tests detect viral DNA loads that may be indicative of an active infection that may warrant the institution of antiviral therapies and/or a decrease of immunosuppressive therapies.

This lab is CLIA-certified.

Our lab provides a variety of clinical testing services targeted to pediatric patients undergoing transplantation or are otherwise immunocompromised.

Adenovirus (AdV) Quantitative Real-Time PCR

EBV occurs commonly in the general population and generally remains latent; however, immunocompromised patients are susceptible to an active EBV infection that can lead to post-transplant lymphoproliferative disorder (PTLD).

Since viremia is considered the best predictor of the disease, monitoring the EBV DNA levels in the blood by quantitative real-time PCR in these patients may allow timely recognition of virus reactivation and permit installment and assessment of antiviral treatment (rituximab) and/or a decrease of immunosuppressive therapies.

References

Kimura H., Morita M., Yabuta Y., Kuzushima K., Kato K., Kojima S., Takaharu M., and Morishima T. (1999). Quantitative analysis of Epstein-Barr virus loads by using a real-time assay. J Clin Microbiol. Vol 37:132-136.

Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a viral infection that rarely causes obvious illness; however, in immunocompromised patients (recipients of solid-organ and bone marrow transplants or individuals infected with HIV), there is an increased risk for difficult eye infections (CMV retinitis), gastrointestinal CMV and encephalitis.

Monitoring CMV DNA levels in blood by quantitative real-time PCR in these patients may allow timely recognition of virus reactivation and permit installment and assessment of antiviral treatment (ganciclovir) and/or a decrease of immunosuppressive therapies.

Epstein-Barr Virus (EBV) Quantitative Real-time PCR

Adenovirus (AdV) infections are associated with respiratory, ocular gastrointestinal disease. Among immunocompromised patients, AdV have increasingly been recognized as significant viral pathogens with high morbidity and mortality (Echavarria 2008).

Monitoring AdV DNA levels of blood by quantitative real-time PCR in these patients may allow timely recognition of virus reactivation and permit installment and assessment of antiviral treatment (IVIG and also cidofavir in severe cases) and/or decrease of immunosuppressive therapies. Depending on a patient’s symptoms, other specimens may be tested, such as respiratory and stool samples.

References

Echavarria M. (2008). Adenoviruses in immunocompromised hosts. Clin Microbiol Rev Oct:704 -715.

Immune Cell Function Assay (ICFA)

ImmuKnow™ — the Cylex® Immune Cell Function Assay detects cell-mediated immunity (CMI) by measuring the concentration of ATP from CD4+ cells following stimulation. This assay is used for the detection of cell-mediated immunity in an immunosuppressed population.

References

1. IMMUKNOW™ - CYLEX® IMMUNE CELL FUNCTION ASSAY: PRODUCT INSERT. 50157.012. Revision January 2010.
2. Detailed instructions on the collection of whole blood by venipuncture may be obtained from “Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture - 3rd Edition (H3-A3),” published by the National Committee for Clinical Laboratory Standards: July 1991, Vol. II, No. 10.

Our research efforts are focused on development of new or improved lab-based assays to aid in the diagnosis and treatment of pediatric disorders.

In Development

The detection and monitoring of BK polyomavirus (BKV) quantitative real-time PCR

BK polyomavirus (BKV) is the primary etiological agent of polyomavirus-associated nephropathy (PVNA), which causes irreversible graft loss in 1% to 10% of kidney transplants (Hirsch 2005, Ramos et al., 2002). BKV-associated hemorrhagic cystitis is a major complication of bone marrow transplants (Arthur et al., 1988).

Monitoring BKV DNA levels of urine and plasma by quantitative real-time PCR in these patients may allow timely recognition of virus reactivation and permit installment of antiviral treatment (IVIG and Levaquin® when identified in urine) and/or a decrease of immunosuppressive therapies.

References

1. Hirsch H. (2005). BK virus: opportunity makes a pathogen. Clin Infect Dis 41:354-360.
2. Ramos E, Drachenberg CB, Portocarrero M, Wali R, Klassen DK, Fink JC. Farney A, Hirsch H, Papadimitriou JC, Cangro CB, Weir MR, ST Bartlett ST. (2002). BK virus nephropathy diagnosis and treatment: experience at the University of Maryland renal transplant program. Clin Transpl 143-153
3. Arthur RR, Shah KV, Charache P, Saral R. (1988). BK and JC virus infections in recipients of bone marrow transplants. J Infect Dis 158:563-569.