1. BK Virus Thea Brennan-Krohn (“BK”) July 2010

2. Polyomaviruses Small DS DNA viruses Cause “poly” “omas” Non-human polyomaviruses: – Murine K virus, discovered 1952 [1] – Simian virus 40 (SV40) Human polyomaviruses: – BK virus (named for the patient’s initials): isolated in 1971 from the urine of a renal allograft recipient with ureteric obstruction [2] – JC virus (also named for the patient’s initials): cultivated in 1971 from the brain of a patient with progressive multifocal leukoencephalopathy in the context of Hodgkin's disease [3] – KI virus (“Karolinska Institutet”): identified 2007 using large-scale molecular virus screening method to identify unrecognized human pathogens. [4] – WU virus (“Washington University”): identified 2007 from respiratory secretions of patients with URI symptoms. [5] – MCV virus: found in Merkel cell carcinomas in 2008 [6] 1.Kilham L. Isolation in Suckling Mice of a Virus from C 3 H Mice Harboring Bittner Milk Agent Science 1952; 116:391 2.Gardner SD. New human papovavirus (B.K.) isolated from urine after renal transplantation. Lancet. 1971 Jun 19;1(7712):1253-7. 3.Padgett BL et al. Cultivation of papova-like virus from human brain with progressive multifocal leucoencephalopathy. Lancet. 1971 Jun 19;1(7712):1257-60 4.Allander T et al. Identification of a third human polyomavirus. J Virol. 2007 Apr;81(8):4130-6. 5.Gaynor AM et al. Identification of a novel polyomavirus from patients with acute respiratory tract infections. PLoS Pathog. 2007 May 4;3(5):e64. 6.Feng H et al. Clonal integration of a polyomavirus in human Merkel cell carcinoma. Science. 2008 Feb 22;319(5866):1096-100.

3. Naming Viruses After Patients: A HIPAA Violation? “James Delany, a man about 50… had an umbilical hernia… Eight days before admission, in struggling to hold a pig, he felt something give way at the tumour…” Plan: “give as much beef-tea and brandy-and- water as he can take, and throw up an enema daily of strained gruel and milk.” From Umbilical Hernia; Sloughing of Four Inches of the Small Intestines; Complete Recovery Br Med J. 1865 July 15; 2(237): 33–35.

4. Epidemiology Seroprevalence peaks at 91% in children 5-9 Overall seropositivity 81%. Antibody titers decrease with age. Mode of transmission uncertain; may be respiratory. Virus can persist in kidney and urinary tract. – BKV DNA can be found in 30 to 50% of normal kidneys and 40% of ureters, primarily in epithelial cells. – In one study, BK viruria was present in 13.5% of normal subjects, 33.3% with renal disease (not translplant recipients), and 55.6% with renal disease and steroid tx. [1] [1] Kaneko T et al. Prevalence of human polyoma virus (BK virus and JC virus) infection in patients with chronic renal disease. Clin Exp Nephrol. 2005 Jun;9(2):132-7.\ Knowles WA et al. Population-based study of antibody to the human polyomaviruses BKV and JCV and the simian polyomavirus SV40. J Med Virol. 2003 Sep;71(1):115-23. Reploeg MD et al. BK Virus: A Clinical Review. Clin Infect Dis. 2001 Jul 15;33(2):191-202.

5. The Virus Small, nonenveloped, double-stranded DNA icosahedral virions. Three structural capsid proteins and three non-capsid regulatory proteins: large T- antigen, small t-antigen, and agnoprotein. White MK; Khalili K. Polyomaviruses and human cancer: molecular mechanisms underlying patterns of tumorigenesis. Virology. 2004 Jun 20;324(1):1-16. Jiang M et al. The role of polyomaviruses in human disease. Virology. 2009 Feb 20;384(2):266-73.

6. Molecular Mechanisms Attachement to a sialic acid receptor Caveolae-mediated endocytosis Intracellular trafficking by microtubules Fusion with Golgi/ER Perinuclear accumulation of virus Dugan AS et al. Update on BK virus entry and intracellular trafficking. Transpl Infect Dis. 2006 Jun;8(2):62-7.

7. Clinical Manifestations Asymptomatic or mild URI in immunocompetant hosts Hemorrhagic cystitis in hematopoietic stem cell transplant recipients Allograft nephropathy in renal transplant recipients Unusual manifestations – Systemic vasculopathy  widespread capillary leakage, MI, death. [1] – Disseminated infection [2,3] – Retinitis [4,5] – Interstitial pneumonia [6] – Ulcers of the colon [7] [1] Petrogiannis-Haliotis T et al. BK-related polyomavirus vasculopathy in a renal-transplant recipient. N Engl J Med 2001; 345:1250. [2] Rosen S et al. Tubulo-interstitial nephritis associated with polyomavirus (BK type) infection. N Engl J Med 1983; 308:1192-6. [3] Vallbracht A et al. Disseminated BK type polyomavirus infection in an AIDS patient associated with central nervous system disease. Am J Pathol 1993;143:29-39. [4] Bratt G et al. BK virus as the cause of meningoencephalitis, retinitis and nephritis in a patient with AIDS. AIDS 1999;13:1071-5. 12. [5] Hedquist BG et al. Identification of BK virus in a patient with acquired immune deficiency syndrome and bilateral atypical retinitis. Ophthalmology 1999;106:129-32. [6] Sandler ES et al. BK papova virus pneumonia following hematopoietic stem cell transplantation. Bone Marrow Transplant 1997;20:163-5 [7] Kim, GY et al. BK virus colonic ulcerations. Clin Gastroenterol Hepatol 2004; 2:175..

8. Polyomavirus Allograft Nephropathy Prevalence among RT recipients ~10%. Higher risk with greater immunosuppression. ATG for rejection (but not for induction) with ProGraf/CellCept/steroid therapy associated with virus replication. Hirsch HH, Knowles W, Dickenmann M, et al. Prospective study of polyomavirus type BK replication and nephropathy in renal-transplant recipients. N Engl J Med 2002; 347: 488.

9. Diagnosis Serum or urine PCR Urine cytology Biopsy Electron microscopy of biopsy or urine Screening by urine cytology or PCR recommended – Every three months for first 2 years post transplant – With graft dysfunction – With all biopsies Hirsch HH. Polyomavirus-associated nephropathy in renal transplantation: interdisciplinary analyses and recommendations. Transplantation 2005 May 27;79(10):1277-86.

10. Diagnosis: Urine Cytology Decoy Cells http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=eurekah&part=A74503

11. Histologic Diagnosis Viral Inclusions http://www.cap.org http://tpis1.upmc.com:81/tpis/GU/G00011a.html

12. Diagnosis: Immunohistochemistry http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=eurekah&part=A74503 Staining for SV40

13. Diagnosis: In Situ Hybridization http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=eurekah&part=A74503

14. Diagnosis: Electron Microscopy A) Free viral particles (~45 nm diameter) shed in the urine. B) Polyoma Allograft Nephropathy: 3D, cast-like polyomavirus aggregates (‘Haufen’) in urine are diagnostic of intra-renal disease. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=eurekah&part=A74503

15. Classification PVAN A (Early) – Viral cytopathic changes: minimal to mild – Inflammatory infiltrates, tubular atrophy, fibrosis: insignificant PVAN B (Florid) – Viral cytopathic changes: mild to severe – Inflammatory infiltrates: moderate to severe – Tubular atrophy, fibrosis: mild PVAN C (Advanced Sclerosing) – Viral cytopathic changes: variable – Inflammatory infiltrates: variable – Tubular atrophy, fibrosis: moderate to severe Hirsch HH et al. Polyomavirus-associated nephropathy in renal transplantation: interdisciplinary analyses and recommendations. Transplantation. 2005 May 27;79(10):1277-86.

16. Prognosis PVAN A (Early): 13% graft loss PVAN B (Florid) – B1 (<25% of biopsy core affected): 40% graft loss – B2 (25-50% of biopsy core affected): 56% graft loss – B3 (>50% of biopsy core affected): 78% graft loss PVAN C (Advanced Sclerosing): 100% graft loss (3/3 cases) Drachenberg CB et al. Histological patterns of polyomavirus nephropathy: correlation with graft outcome and viral load. Am J Transplant. 2004 Dec;4(12):2082-92.

17. Treatment: Adjustment of Immunosuppression Reduction of immunosuppression – Tacrolimus trough <6 ng/mL – MMF <1 gm/day – Cyclosporine A trough 100-150 ng/mL – Discontinuation of tacrolimus or MMF Change in immunosuppression – Tacrolimus  cyclosporine A or sirolimus – MMF  azathioprine, sirolimus or leflunomide Hirsch HH et al. Polyomavirus-associated nephropathy in renal transplantation: interdisciplinary analyses and recommendations. Transplantation. 2005 May 27;79(10):1277-86.

18. Treatment: Cidofovir Cytosine-phosphate analog, originally used for CMV retinitis in patients with AIDS Shown to have in vitro activity against BK virus Concentrates in tubular epithelial cells and urine A few studies have shown improvement in patients treated with cidofovir, but no RCTs. [1-3] – In one study patients treated with cidofovir had no decline in BKV and had decreased renal function compared to those not treated. [4] 0.25– 0.33 mg/kg IV q2–3 weeks (10–20% of the CMV dose) without probenicid. [5] [1] Vats A, Shapiro R, Singh RP, et al. Quantitative viral load monitoring and cidofovir therapy for the management of BK virus-associated nephropathy in children and adults. Transplantation 2003; 75: 105. [2] Kadambi PV, Josephson MA, Williams J, et al. Treatment of refractory BK virus-associated nephropathy with cidofovir. Am J Transplant 2003; 3: 186. [3] Vats A, Shapiro R, Randhawa PS, et al. BK Virus associated nephropathy and cidofovir: long term experience. Am J Transplantation 2003; 3: 190 (Abstract #148). [4]Pallet N. Cidofovir may be deleterious in BK virus-associated nephropathy. Transplantation. 2010 Jun 27;89(12):1542-4. [5] Hirsch HH et al. Polyomavirus-associated nephropathy in renal transplantation: interdisciplinary analyses and recommendations. Transplantation. 2005 May 27;79(10):1277-86.

19. Treatment: Leflunomide A disease-modifying anti-rheumatic drug In one study, 12/13 patients treated by exchanging leflunomide for MMF and lowering the trough level of the calcineurin-inhibitor cleared the virus. [1] In another study 5/12 pts treated by exchanging leflunomide for MMF and decreasing immunosuppresion cleared the virus. [2] [1] Teschner S et al. Leflunomide therapy for polyomavirus-induced allograft nephropathy: efficient BK virus elimination without increased risk of rejection. Transplant Proc. 2009 Jul-Aug;41(6):2533-8. [2] Faguer S. Leflunomide treatment for polyomavirus BK-associated nephropathy after kidney transplantation. Transpl Int. 2007 Nov;20(11):962-9. Epub 2007 Jul 30. Johnston O et al. Treatment of polyomavirus infection in kidney transplant recipients: a systematic review. Transplantation. 2010 May 15;89(9):1057-70.

20. Other Treatment Possibilities IVIg Ciprofloxacin

21. The Future Do more studies Invent new drugs