1
|
Rasmussen DB, Møller DL, Hamm SR, Borges ÁH, Nielsen ACY, Kirkby NS, Sørensen SS, Nielsen SD. BKPyV DNAemia in Kidney Transplant Recipients Undergoing Regular Screening: A Single-Centre Cohort Study. Microorganisms 2023; 12:65. [PMID: 38257892 PMCID: PMC10819282 DOI: 10.3390/microorganisms12010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/16/2023] [Accepted: 12/22/2023] [Indexed: 01/24/2024] Open
Abstract
Infection with BK polyomavirus (BKPyV) is a common opportunistic infection after kidney transplantation (KT) and may affect graft function. We aimed to determine the incidence, risk factors, and clinical outcomes of BKPyV DNAemia in a prospective cohort of 601 KT recipients transplanted from 2012 to 2020. BKPyV PCR on plasma was performed at days 60, 90, 180, 270, and 360 post-KT. Any BKPyV DNAemia was defined as a single BKPyV DNA of ≥1000 copies/mL. Severe BKPyV DNAemia was defined as two consecutive BKPyV DNA of ≥10,000 copies/mL. Cumulative incidences were investigated using the Aalen-Johansen estimator, and the risk factors were investigated in Cox proportional hazard models. The incidence of any BKPyV DNAemia and severe BKPyV DNAemia was 21% (18-25) and 13% (10-16) at one year post-KT, respectively. Recipient age > 50 years (aHR, 1.72; 95% CI 1.00-2.94; p = 0.049), male sex (aHR, 1.96; 95% CI 1.17-3.29; p = 0.011), living donors (aHR, 1.65; 95% CI 1.03-2.74; p = 0.045), and >3 HLA-ABDR mismatches (aHR, 1.72; 95% CI 1.01-2.94; p = 0.046) increased the risk of severe BKPyV DNAemia. Any BKPyV DNAemia was associated with an increased risk of graft function decline (aHR, 2.26; 95% CI 1.00-5.12; p = 0.049), and severe BKPyV DNAemia was associated with an increased risk of graft loss (aHR, 3.18; 95% CI 1.06-9.58; p = 0.039). These findings highlight the importance of BKPyV monitoring post-KT.
Collapse
Affiliation(s)
- Daniel B. Rasmussen
- Viro-Immunology Research Unit, Department of Infectious Diseases 8632, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (D.B.R.); (D.L.M.); (S.R.H.)
| | - Dina L. Møller
- Viro-Immunology Research Unit, Department of Infectious Diseases 8632, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (D.B.R.); (D.L.M.); (S.R.H.)
| | - Sebastian R. Hamm
- Viro-Immunology Research Unit, Department of Infectious Diseases 8632, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (D.B.R.); (D.L.M.); (S.R.H.)
| | - Álvaro H. Borges
- Department of Infectious Disease Immunology, Statens Serum Institut, 2300 Copenhagen, Denmark;
- Centre of Excellence for Health, Immunity and Infections (CHIP), Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Alex C. Y. Nielsen
- Department of Clinical Microbiology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (A.C.Y.N.); (N.S.K.)
| | - Nikolai S. Kirkby
- Department of Clinical Microbiology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (A.C.Y.N.); (N.S.K.)
| | - Søren S. Sørensen
- Department of Nephrology, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark;
- Department of Clinical Medicine, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Susanne D. Nielsen
- Viro-Immunology Research Unit, Department of Infectious Diseases 8632, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark; (D.B.R.); (D.L.M.); (S.R.H.)
- Department of Clinical Medicine, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark
| |
Collapse
|
2
|
Characteristics, risk factors and outcome of BKV nephropathy in kidney transplant recipients: a case-control study. BMC Infect Dis 2023; 23:74. [PMID: 36747162 PMCID: PMC9903532 DOI: 10.1186/s12879-023-08043-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Following kidney transplantation, BK virus associated nephropathy (BKVN) occurs in 1 to 10% of kidney transplant recipients (KTR) and represents a major cause of graft loss. We aim at identifying factors associated with biopsy proven BKVN among KTR. METHODS We conducted a retrospective case-control study including all KTR with a biopsy-proven diagnosis of BKVN between 2005 and 2019. Clinical characteristics and outcome were described. For each case, one control KTR without BKV infection was identified and matched by age, transplant date, and donor status. Factors associated with BKVN diagnosis were identified using exact conditional logistic regression. Comparative survival was described using Kaplan-Meier estimator. RESULTS Sixty-four cases of BKVN were identified among 1737 new kidney transplantation (3.7% prevalence). Clinical characteristics did not differ between groups, except for a higher c-PRA among cases. BKVN occurred in a median time of 11 (5-14.5) months after KT, and was associated with a significantly impaired graft function at diagnosis. Following BKVN, 61 (95%) of the patients had immunosuppression reduction, which led to BKV DNAemia resolution in 49% of cases. In multivariate analysis, factors associated with BKVN diagnosis were lymphopenia < 500/mm3 and a prednisone dose > 7.5 mg/day. Median duration of follow-up was 40 months for both groups. BKVN was associated with a significantly increased risk of graft rejection (P = 0.02) and return to dialysis (P = 0.01). CONCLUSIONS BKVN remains a severe complication in KTR and is associated with an increased risk for acute rejection and return to dialysis. Lymphopenia below 500/mm3 and corticosteroid maintenance therapy are significantly associated with biopsy-proven BKVN diagnosis.
Collapse
|
3
|
Myint TM, Chong CHY, Wyld M, Nankivell B, Kable K, Wong G. Polyoma BK Virus in Kidney Transplant Recipients: Screening, Monitoring, and Management. Transplantation 2022; 106:e76-e89. [PMID: 33908382 DOI: 10.1097/tp.0000000000003801] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Polyomavirus BK virus (BKPyV) infection is an important complication of kidney transplantation and allograft failure. The prevalence of viremia is 10%-15%, compared with BK-associated nephropathy (BKPyVAN) at 3%-5%. Given that there are no effective antiviral prophylaxis or treatment strategies for BKPyVAN, active screening to detect BKPyV viremia is recommended, particularly during the early posttransplant period. Immunosuppression reduction to allow viral clearance may avoid progression to severe and irreversible allograft damage. The frequency and duration of screening are highly variable between transplant centers because the evidence is reliant largely on observational data. While the primary treatment goals center on achieving viral clearance through immunosuppression reduction, prevention of subsequent acute rejection, premature graft loss, and return to dialysis remain as major challenges. Treatment strategies for BKPyV infection should be individualized to the recipient's underlying immunological risk and severity of the allograft infection. Efficacy data for adjuvant therapies including intravenous immunoglobulin and cidofovir are sparse. Future well-powered and high-quality randomized controlled trials are needed to inform evidence-based clinical practice for the management of BKPy infection.
Collapse
Affiliation(s)
- Thida Maung Myint
- Sydney School of Public Health, University of Sydney, Sydney, NSW, Australia
- Newcastle Transplant Unit, John Hunter Hospital, Newcastle, NSW, Australia
| | - Chanel H Y Chong
- Sydney School of Public Health, University of Sydney, Sydney, NSW, Australia
| | - Melanie Wyld
- Department of Renal Medicine, Centre for Transplant and Renal Research, Westmead Hospital, Westmead, NSW, Australia
| | - Brian Nankivell
- Department of Renal Medicine, Centre for Transplant and Renal Research, Westmead Hospital, Westmead, NSW, Australia
| | - Kathy Kable
- Department of Renal Medicine, Centre for Transplant and Renal Research, Westmead Hospital, Westmead, NSW, Australia
| | - Germaine Wong
- Sydney School of Public Health, University of Sydney, Sydney, NSW, Australia
- Department of Renal Medicine, Centre for Transplant and Renal Research, Westmead Hospital, Westmead, NSW, Australia
- Centre for Kidney Research, The Children's Hospital at Westmead, Westmead, NSW, Australia
| |
Collapse
|
4
|
BK Virus-Associated Nephropathy after Renal Transplantation. Pathogens 2021; 10:pathogens10020150. [PMID: 33540802 PMCID: PMC7913099 DOI: 10.3390/pathogens10020150] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 02/06/2023] Open
Abstract
Recent advances in immunosuppressive therapy have reduced the incidence of acute rejection and improved renal transplantation outcomes. Meanwhile, nephropathy caused by BK virus has become an important cause of acute or chronic graft dysfunction. The usual progression of infection begins with BK viruria and progresses to BK viremia, leading to BK virus associated nephropathy. To detect early signs of BK virus proliferation before the development of nephropathy, several screening tests are used including urinary cytology and urinary and plasma PCR. A definitive diagnosis of BK virus associated nephropathy can be achieved only histologically, typically by detecting tubulointerstitial inflammation associated with basophilic intranuclear inclusions in tubular and/or Bowman’s epithelial cells, in addition to immunostaining with anti-Simian virus 40 large T-antigen. Several pathological classifications have been proposed to categorize the severity of the disease to allow treatment strategies to be determined and treatment success to be predicted. Since no specific drugs that directly suppress the proliferation of BKV are available, the main therapeutic approach is the reduction of immunosuppressive drugs. The diagnosis of subsequent acute rejection, the definition of remission, the protocol of resuming immunosuppression, and long-term follow-up remain controversial.
Collapse
|
5
|
Screening for BKV-DNAEMIA after renal transplantation in a resource limited setting. Diagn Microbiol Infect Dis 2020; 96:114979. [PMID: 32014346 DOI: 10.1016/j.diagmicrobio.2019.114979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 12/18/2019] [Accepted: 12/25/2019] [Indexed: 11/21/2022]
Abstract
Costs may hinder the implementation of BK polyomavirus (BKV)-DNAemia screening in resource-limited kidney transplant (KT) centers. We analyzed data from two studies to assess the performance and potential cost saving of a dual-step screening strategy based on the use of a preliminary qualitative semi-nested PCR (snPCR) assay followed by BKV-DNAemia quantification after KT. In the preliminary study, in which 130 samples from 33 KT recipients were screened for BKV-DNAemia, the estimated positive and negative predictive values of snPCR, as compared to quantitative PCR (qPCR), were 88% and 99%, respectively. In the second study, which included 84 KT recipients, BKV-DNAemia was detected by snPCR in 28/472 (5.9%) samples and confirmed by qPCR in 26 samples of 21 (25%) subjects. No graft loss occurred among KT recipients who developed BKV-DNAemia. Cost analyses suggested that this strategy might be a cost saving alternative for BKV-DNAemia screening for some resource-limited settings.
Collapse
|
6
|
Chong S, Antoni M, Macdonald A, Reeves M, Harber M, Magee CN. BK virus: Current understanding of pathogenicity and clinical disease in transplantation. Rev Med Virol 2019; 29:e2044. [PMID: 30958614 DOI: 10.1002/rmv.2044] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 12/19/2022]
Abstract
BK polyomavirus (BKV) is an important cause of graft loss in renal transplant recipients that continues to pose a significant challenge to clinicians due to its frequently unpredictable onset, persistence, and the lack of effective antiviral agents or prevention strategies. This review covers our current understanding of epidemiology, viral transmission and disease progression, and treatment and prevention strategies that have been used to manage this disease.
Collapse
Affiliation(s)
- Stephanie Chong
- Department of Renal Medicine, Royal Free Hospital, University College London, London, UK
| | - Michelle Antoni
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, London, UK
| | - Andrew Macdonald
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, London, UK
| | - Matthew Reeves
- Institute of Immunity and Transplantation, Royal Free Hospital, University College London, London, UK
| | - Mark Harber
- Department of Renal Medicine, Royal Free Hospital, University College London, London, UK
| | - Ciara N Magee
- Department of Renal Medicine, Royal Free Hospital, University College London, London, UK
| |
Collapse
|
7
|
Demey B, Tinez C, François C, Helle F, Choukroun G, Duverlie G, Castelain S, Brochot E. Risk factors for BK virus viremia and nephropathy after kidney transplantation: A systematic review. J Clin Virol 2018; 109:6-12. [PMID: 30343190 DOI: 10.1016/j.jcv.2018.10.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/13/2018] [Accepted: 10/08/2018] [Indexed: 01/15/2023]
Abstract
In the last 20 years, the management of BK polyomavirus (BKPyV) reactivation in kidney transplant patients has become a true challenge for the transplant community. The only treatment option is based on the early identification of at-risk patients. The number of reported risk factors for BKPyV reactivation has increased markedly in the literature last years, although they are sometimes in an unclear or contradictory manner. Our purpose is to provide a systematic review and meta-analysis of risk factors for BKPyV viremia and nephropathy described in multivariate analyses. The PubMed database was searched for prospective or prospectively-based observational studies on risk factors for BKPyV viremia and/or nephropathy. Our qualitative assessment of risk factors was based on the odds ratios and hazard ratios calculated in multivariate regression analyses. Of the 241 publications screened, 34 were included in the qualitative analysis. In all, 144 and 19 distinct factors were analyzed for BKPyV viremia and for BKPyV nephropathy, respectively. Our evaluation highlighted eight risk factors for BKPyV viremia: a tacrolimus regimen, a deceased donor, a male recipient, a history of previous transplant, age at transplantation, ureteral stent use, delayed graft function, and acute rejection episodes increased the risk of BKV viremia to varying extents. Tacrolimus and acute rejection episodes were also associated with a higher incidence of BKPyV nephropathy. BKPyV reactivation is a serious complication after renal transplantation. With a view to combating this problem, existing data should be published in full, and new prospective international multicenter studies should be performed.
Collapse
Affiliation(s)
- Baptiste Demey
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - Claire Tinez
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - Catherine François
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - François Helle
- AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - Gabriel Choukroun
- Department of Nephrology, Amiens University Medical Center, Amiens, France
| | - Gilles Duverlie
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - Sandrine Castelain
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France
| | - Etienne Brochot
- Department of Virology, Amiens University Medical Center, Amiens, France; AGIR Research Unit, EA 4294, Jules Verne University of Picardie, Amiens, France.
| |
Collapse
|
8
|
Hertz-Tang AL, Astor BC, Mandelbrot DA, Mohamed MA, Djamali A, Parajuli S. BK viremia is not associated with adverse outcomes in the absence of BK nephropathy. Clin Transplant 2018; 32:e13283. [PMID: 29774593 DOI: 10.1111/ctr.13283] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2018] [Indexed: 01/02/2023]
Abstract
There are limited data regarding the association of different levels of BK viremia and BK nephropathy (BKN), and graft outcomes. We studied the BK plasma PCR levels of all kidney transplant recipients (KTR) transplanted at our institution between 01/01/2006 and 06/30/2014. Patients were divided into groups based on their highest BK plasma PCR level within the first year following transplantation: undetectable, low (<1000 copies/mL), moderate (1000-10 000 copies/mL), high (>10 000-100 000 copies/mL), very high (>100 000 copies/mL), and those that had biopsy-proven BKN. There were a total of 1146 KTR during the study period: 813 with undetectable BK levels and 333 with any detectable BK level (87 with low, 79 with moderate, 88 with high, 34 with very high level BK, and 45 that had BKN). Compared to KTR with an undetectable BK level, incidence of mortality, graft failure, rejections,and infections were not significantly different for those with low, moderate, high, or very high BK level. Patients with BKN had a higher rate of infection and higher rates of total graft failure or death-censored graft failure compared to those with undetectable BK levels. BK viremia in the absence of BKN does not significantly increase the risk of rejection, infections, or graft failure compared to an undetectable BK level.
Collapse
Affiliation(s)
- Amber L Hertz-Tang
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Brad C Astor
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Department of Population Health Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Didier A Mandelbrot
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Maha A Mohamed
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Arjang Djamali
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sandesh Parajuli
- Division of Nephrology, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| |
Collapse
|
9
|
BK polyomavirus genotypes Ia and Ib1 exhibit different biological properties in renal transplant recipients. Virus Res 2017; 243:65-68. [PMID: 29106916 DOI: 10.1016/j.virusres.2017.10.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/26/2017] [Accepted: 10/26/2017] [Indexed: 01/27/2023]
Abstract
BK polyomavirus (BKV) is an opportunist agent associated with nephropathy (BKVAN) in 1-10% of kidney transplant recipients. BKV is classified into genotypes or subgroups according to minor nucleotidic variations with unknown biological implications. Studies assessing the possible association between genotypes and the risk of BKVAN in kidney transplant patients have presented conflicting results. In these studies, genotype Ia, which is highly prevalent in Brazil, was less frequently found and, thus, comparative data on the biological properties of this genotype are lacking. In this study, BKV Ia and Ib1 genotypes were compared according to their viral load, genetic evolution (VP1 and NCCR) - in a cohort of renal transplant recipients. The patients infected with Ia (13/23; 56.5%) genotype exhibited higher viral loads in urine [>1.4 log over Ib1 (10/23; 43.5%); p=0.025]. In addition, genotype Ia was associated with diverse mutations at VP1 loops and sites under positive selection outside loops, which were totally absent in Ib1. Although the number of viremic patients was similar, the three patients who had BK nephropathy (BKVAN) were infected with Ia genotype. NCCR architecture (ww or rr) were not distinctive between Ia and Ib1 genotypes. Ia genotype, which is rare in other published BKV cohorts, presented some diverse biological properties in transplanted recipients in comparison to Ib1.
Collapse
|
10
|
Dvir R, Paloschi V, Canducci F, Dell'Antonio G, Racca S, Caldara R, Pantaleo G, Clementi M, Secchi A. IL28B rs12979860 genotype as a predictor marker of progression to BKVirus Associated nephropathy, after kidney transplantation. Sci Rep 2017; 7:6746. [PMID: 28751760 PMCID: PMC5532253 DOI: 10.1038/s41598-017-06915-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 06/05/2017] [Indexed: 12/22/2022] Open
Abstract
BK virus (BKV) associated nephropathy (BKVAN) is still an important cause of allograft dysfunction after kidney transplantation (KT). Recent data have shown that the new interferon (IFN)-λ family has been ascribed antiviral properties similar to IFNα, and that the response to IFNλ in kidney is restricted to epithelial cells, suggesting that the IFNλ system evolves as specific protection of the epithelia. We aimed to test the hypothesis of correlation between a single nucleotide polymorphism (C/T dimorphism rs12979860) in the genomic region of IL28B and BKVAN, in patients after KT. Fifty kidney-transplanted patients were included as follow: Group 1 (BKV+/BKVAN+): 11 patients with active BKV- replication and biopsy-proven BKVAN; Group 2 (BKV+/BKVAN-): 22 patients with active BKV- replication but without evidence of BKVAN; Group 3 (BKV-/BKVAN-): 17 patients without evidence of BKV- replication (control group). Here we show that the C/C genotype was statistically higher in group 2 than in group 1 and BKVAN was detected significantly more frequently in patients with C/T and T/T genotypes than in patients with C/C genotype. We therefore propose IL28B polymorphism (rs12979860), as a predictor-marker to differentiate between patients with self-limited, even if persistent, BKV- reactivation and patients with a high risk of progression towards BKVAN, and to modulate the clinical management of these patients accordingly.
Collapse
Affiliation(s)
- Roee Dvir
- Laboratory of Clinical Microbiology & Virology, San Raffaele Hospital IRCCS, Milan, Italy
| | - Vera Paloschi
- Transplant Unit, Department of Internal Medicine, San Raffaele Hospital IRCCS, Milan, Italy
| | - Filippo Canducci
- Laboratory of Clinical Microbiology & Virology, San Raffaele Hospital IRCCS, Milan, Italy
- University of Insubria, Dept. of Biotechnology and Life Sciences, Varese, Italy
| | | | - Sara Racca
- Laboratory of Clinical Microbiology & Virology, San Raffaele Hospital IRCCS, Milan, Italy
| | - Rossana Caldara
- Transplant Unit, Department of Internal Medicine, San Raffaele Hospital IRCCS, Milan, Italy
| | - Giuseppe Pantaleo
- UniSR-Social.Lab [Research Methods], Faculty of Psychology, Vita Salute San Raffaele University, Milan, Italy
| | - Massimo Clementi
- Laboratory of Clinical Microbiology & Virology, San Raffaele Hospital IRCCS, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Antonio Secchi
- Transplant Unit, Department of Internal Medicine, San Raffaele Hospital IRCCS, Milan, Italy.
- Vita-Salute San Raffaele University, Milan, Italy.
| |
Collapse
|