Molecular characterization and sequence analysis of polyomavirus BKV-strain in a renal-allograft recipient.
The significance of polyomavirus (PV) infection was investigated in a 53-year-old patient who underwent renal transplantation and was treated with triple immunosuppressive therapy (tacrolimus, prednisone, and azathioprine). A renal biopsy taken because of the suspicion of acute rejection showed focal inflammatory interstitial infiltration, tubulitis, and tubular cell nuclear changes consistent with the hypothesis of viral infection. Both the tubular and decoy cells identified by means of urinalysis positively stained for anti-SV40 antibody. Polymerase chain reaction performed on the DNA extracted from renal tissue and isolated from urine showed the presence of an antigenic variant (AS) of the BKV archetype after sequence analysis of the transcription control region (TCR). On the basis of the diagnosis of BKV infection, immunosuppressive therapy was reduced. The patient's renal function improved and was still stable 8 months later when urinalysis showed only a few decoy cells, which were found to be infected by JC but not BK virus. These data suggest that only the BKV, probably favoured by immunosuppressive therapy (tacrolimus), causes renal damage. It is worth underlining that even small and sporadic viral genome mutations may lead to pathologic effects.
Boldorini
R
R
Dipartimento di Scienze Mediche Facoltà di Medicina e Chirurgia, Università "Amedeo Avogadro" del Piemonte Orientale, Novara, Italy.
Zorini
E O
EO
Fortunato
M
M
Bernardi
M
M
Suno
A
A
Benigni
E
E
Monga
G
G
Mazzucco
G
G
D001739:BK Virus / Q000235:genetics*; D001706:Biopsy; D004279:DNA, Viral / Q000737:chemistry; D006084:Graft Rejection / Q000821:virology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects; D007674:Kidney Diseases / Q000473:pathology / Q000821:virology; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D027601:Polyomavirus Infections / Q000473:pathology; D017422:Sequence Analysis, DNA; D016559:Tacrolimus / Q000009:adverse effects; D014184:Transplantation, Homologous; D014556:Urine / Q000166:cytology
D004279:DNA, Viral; D007166:Immunosuppressive Agents; D016559:Tacrolimus