This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Kidney), Subject name: Pathology
An emerging organism responsible for causing Pyelonephritis in Renal Allografts is? 
Select and explain. 
A. Polyoma virus, B. Herpes virus, C. Hepatitis B virus, D. Rota virus
A: Polyoma virus
Answer: A: Polyoma virus 
Explanation: ANSWER: (A) Polyoma virusREF: With text"An emerging viral pathogen causing pyelonephritis in kidney allografts is polyoma virus"REF: Robbins and Cotran pathologic basis of disease 7th edition Volume 1 page 1000"The current average half-life of a kidney transplant is 8 to 10 years. Allograft loss can occur from rejection (cell mediated or antibody mediated), recurrent urinary tract infections, polyoma virus associated nephropathy or recurrent kidney disease" REF: Mayo Clinic Internal Medicine Board Review 9th edition by Amit Ghosh page 658