The Importance of 1-Year Protocol Biopsy in the Long-Term Prognosis of Kidney Transplants-5-Years Follow-Up.

BACKGROUND: Protocol biopsies are performed to detect subclinical pathologies that may lead to future graft dysfunction. However, they are not routinely performed interventions in every transplant center. There is no established regimen for performing them. PURPOSE: The study aimed to evaluate if protocol biopsies can improve long-term patient outcomes after detecting early disorders and modifying treatment. MATERIAL AND METHODS: Our observational study included 61 patients who underwent protocol biopsy 12 months after the transplantation. Based on the biopsy results, patients with abnormal histologic material (n = 37) were divided into 3 study groups as follows: patients with mild inflammatory lesions (n = 21), patients with interstitial fibrosis and tubular atrophy (IFTA) grade II to III (n = 12), and patients with BK virus nephropathy (n = 4). The control group (n = 24) included kidney recipients with IFTA 0 to I grade. Outcomes after 5-year follow-up were evaluated. RESULTS: Five years after the biopsy, patients in the control group had stable graft function (5-year change in serum creatinine was -0.09 mg/dL). An increase in serum creatinine levels was observed in patients with IFTA II to III compared with the control group (0.14 mg/dL, P = .04). Immunosuppressive treatment was modified in the group with mild inflammatory changes and in the BKV group after the biopsy result. In the group with mild inflammatory lesions, renal function was stable (change of serum creatinine was -0.01 mg/dL, P = .51). In the BKV nephropathy group, there was a significant reduction in serum creatine levels (-0.48 mg/dL, P = .016). The analysis showed no diagnostic value for serum creatinine concentration (95% CI 0.49-0.78, P = .08). CONCLUSIONS: Protocol biopsies are useful for detecting early pathologies and preventing allograft failure. They greatly benefit patients with detectable pathology that can be treated or in whom therapy modification is possible.

Potential utility of urinary chemokine CCL2 to creatinine ratio in prognosis of 5-year graft failure and mortality post 1-year protocol biopsy in kidney transplant recipients.

BACKGROUND: Chemokines (chemotactic cytokines) are small proteins which are engaged in many pathophysiological processes, including inflammation and homeostasis. In recent years, application of chemokines in transplant medicine was intensively studied. The aim of this study was to determine the utility of urinary chemokines CCL2 (C-C motif ligand 2) and CXCL10 (C-X-C motif chemokine ligand 10) in prognosis of 5-year graft failure and mortality post 1-year protocol biopsy in renal transplant recipients. METHODS: Forty patients who had a protocol biopsy 1 year after renal transplantation were included. Concentrations of CCL2 and CXCL10 in urine with reference to urine creatinine were measured. All patients were under the supervision of one transplant center. Long-term outcomes within 5 years after 1-year posttransplant biopsy were analyzed. RESULTS: Urinary CCL2:Cr at the time of biopsy was significantly increased in patients who died or had graft failure. CCL2:Cr was proven to be a significant predictor of 5-year graft failure and mortality (odds ratio [OR]: 1.09, 95% confidence interval [CI]: 1.02-1.19, p = .02; OR: 1.08, 95% CI: 1.02-1.16, p = .04; respectively). CONCLUSION: Chemokines are easily detected by current methods. In the era of personalized medicine, urinary CCL2:Cr can be considered as a factor providing complementary information regarding risk of graft failure or increased mortality.

Antiviral prophylaxis, male sex, and killer immunoglobulin-like receptor KIR2DL3 as markers for stratifying the risk of BK polyomavirus-associated nephropathy in kidney transplant recipients.

INTRODUCTION: The risk of polyomavirus­associated nephropathy (PyVAN) currently ranges from 1% to 10%, and the risk of graft loss is 10% to 50% within 2 years post­diagnosis. There is currently no specific antiviral therapy against BK polyomavirus (BKPyV), and no therapeutic approach has been proven superior. Natural killer cells play a key role in the defense against viral infections. OBJECTIVES: A retrospective, single­center cohort study was performed to investigate the association between the kidney transplant recipients' killer­cell immunoglobulin­like receptor (KIR) genotype and PyVAN. We also evaluated other possible risk factors for the occurrence of PyVAN in a population of kidney transplant recipients. PATIENTS AND METHODS: DNA samples from 134 kidney transplant recipients were identified for the presence or absence of variable KIR genes and their HLA ligands using polymerase chain reaction with sequence­specific primers. RESULTS: The analysis revealed that the presence of the inhibitory KIR2DL3 (P = 0.03) was a risk factor for posttransplant PyVAN. We also found that the presence of acute rejection before PyVAN (P = 0.02), male sex (P = 0.04), and the lack of antiviral prophylaxis (P = 0.01) were additional risk factors for posttransplant PyVAN. CONCLUSIONS: Our findings confirm that the KIR/HLA genotype plays a significant role in the development of PyVAN and suggest the contribution of both environmental and genetic factors to the incidence of BKPyV infection after kidney transplantation.

Extrapulmonary Manifestations of SARS-CoV-2: A Report of 3 Cases and a Literature Review.

BACKGROUND COVID-19 disease, caused by the SARS-CoV-2 virus, has been one of the greatest challenges in modern medicine. It is mostly known to affect the pulmonary system, leading to pneumonia and acute respiratory distress syndrome, but there is a growing body of evidence of extrapulmonary manifestations of COVID-19 disease. CASE REPORT This article presents 3 cases of various extrapulmonary symptoms of COVID-19 disease and a literature review of similar clinical cases. Two patients had a medical history of living-donor kidney transplantation, and 1 patient was a kidney donor. We present symptoms, diagnostic processes, laboratory and imaging results, and treatment approach. Patient 1 was 29-year-old woman with new-onset diabetes mellitus due to SARS-CoV-2, which required temporary insulin treatment. Patient 2 was a 34-year-old man with fever, chronic fatigue, back pain, and abdominal pain. Imagining showed acalculous cholecystitis, epiploic appendagitis of the right colic flexure, and inflammation of pericardial fat pad in the left cardiophrenic angle. Coagulopathy due to COVID-19 was the most probable cause of the described processes. Therapeutic doses of low-molecular-weight heparin were administered. Patient 3 was a 68-year-old male kidney donor who had painless, nodular, reddening lesions on both shins, accompanied by itching on both shins and recurrent fever. The diagnosis of erythema nodosum during COVID-19 was made. After treatment with low-molecular-weight heparin, significant decreases of symptoms were observed. CONCLUSIONS We conclude that SARS-CoV-2 infection can have a varied course and can involve other systems and organs. Physicians should be aware of possible extrapulmonary symptoms associated with infection with this virus. Correct diagnosis is a prerequisite for proper treatment and prevention of unexpected complications.

Immunity after COVID-19 Recovery and Vaccination: Similarities and Differences.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is associated with a robust immune response. The development of systemic inflammation leads to a hyperinflammatory state due to cytokine release syndrome during severe COVID-19. The emergence of many new SARS-CoV-2 variants across the world deteriorates the protective antiviral immunity induced after infection or vaccination. The innate immune response to SARS-CoV-2 is crucial for determining the fate of COVID-19 symptomatology. T cell-mediated immunity is the main factor of the antiviral immune response; moreover, SARS-CoV-2 infection initiates a rapid B-cell response. In this paper, we present the current state of knowledge on immunity after COVID-19 infection and vaccination. We discuss the mechanisms of immune response to various types of vaccines (nucleoside-modified, adenovirus-vectored, inactivated virus vaccines and recombinant protein adjuvanted formulations). This includes specific aspects of vaccination in selected patient populations with altered immune activity (the elderly, children, pregnant women, solid organ transplant recipients, patients with systemic rheumatic diseases or malignancies). We also present diagnostic and research tools available to study the anti-SARS-CoV-2 cellular and humoral immune responses.

The Immunology of SARS-CoV-2 Infection and Vaccines in Solid Organ Transplant Recipients.

Since its outbreak in December 2019, the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), led to an enormous rise in scientific response with an excess of COVID-19-related studies on the pathogenesis and potential therapeutic approaches. Solid organ transplant (SOT) recipients are a heterogeneous population with long-lasting immunosuppression as a joining element. Immunocompromised patients are a vulnerable population with a high risk of severe infections and an increased infection-related mortality rate. It was postulated that the hyperinflammatory state due to cytokine release syndrome during severe COVID-19 could be alleviated by immunosuppressive therapy in SOT patients. On the other hand, it was previously established that T cell-mediated immunity, which is significantly weakened in SOT recipients, is the main component of antiviral immune responses. In this paper, we present the current state of science on COVID-19 immunology in relation to solid organ transplantation with prospective therapeutic and vaccination strategies in this population.

Assessment of the Banff Working Group classification of definitive BK polyomavirus nephropathy.

Polyomavirus associated nephropathy (PyVAN) continues to be a burden in renal transplantation leading to allograft insufficiency or graft failure. A presumptive diagnosis of PyVAN is made based on the presence of BK polyomavirus in patients' plasma; however, kidney biopsy remains the gold standard to establish a definitive diagnosis. The Banff Working Group on PyVAN proposed a novel classification of definitive PyVAN based on polyomavirus replication/load level and the extent of interstitial fibrosis. The aim of our study was to test the newly defined classes of PyVAN using independent cohorts of 124 kidney transplant patients with PyVAN with respect to the initial presentation and outcome, and to compare our analysis to that previously reported. Detailed analysis of our cohort revealed that the proposed classification of PyVAN did not stratify or identify patients at increased risk of allograft failure. Specifically, while class 3 was associated with the worst prognosis, there was no significant difference between the outcomes in classes 1 and 2. We also found that the timing post-transplantation and inflammation in areas of interstitial fibrosis and tubular atrophy might be additional factors contributing to an unfavorable allograft outcome in patients with PyVAN.

Urinary MicroRNA-21-5p as Potential Biomarker of Interstitial Fibrosis and Tubular Atrophy (IFTA) in Kidney Transplant Recipients.

Chronic renal allograft dysfunction (CAD) is a major limiting factor of long-term graft survival. The hallmarks of progressive CAD are interstitial fibrosis and tubular atrophy (IFTA). MicroRNAs are small, regulatory RNAs involved in many immunological processes. In particular, microRNA-21-5p (miR-21) is considered to be strongly associated with pathogenesis regarding tubulointerstitium. The aim of this study was to assess urinary miR-21 expression levels in the kidney transplant recipients and determine their application in the evaluation of IFTA and kidney allograft function. The expression levels of miR-21 were quantified in the urine of 31 kidney transplant recipients with biopsy-assessed IFTA (IFTA 0 + I: n = 17; IFTA II + III: n = 14) by real-time quantitative PCR. Urine samples were collected at the time of protocolar biopsies performed 1 or 2 years after kidney transplantation. MicroRNA-191-5p was used as reference gene. MiR-21 was significantly up-regulated in IFTA II + III group compared to IFTA 0 + I group (p = 0.003). MiR-21 correlated significantly with serum concentration of creatinine (r = 0.52, p = 0.003) and eGFR (r = -0.45; p = 0.01). ROC analysis determined the diagnostic value of miR-21 with an area under curve (AUC) of 0.80 (p = 0.0002), sensitivity of 0.86 and specificity of 0.71. miR-21 is associated with renal allograft dysfunction and IFTA. Therefore, it could be considered as a potential diagnostic, non-invasive biomarker for monitoring renal graft function.

Urinary levels of CCL2 and CXCL10 chemokines as potential biomarkers of ongoing pathological processes in kidney allograft: an association with BK virus nephropathy.

INTRODUCTION: Early prognostic markers that identify high­risk kidney transplant recipients may lead to optimization of immunosuppressive therapy and improved long­term outcomes. OBJECTIVES: The aim of this study was to assess whether the measurement of urinary concentrations of CCL2 and CXCL10 chemokines can be a valuable noninvasive tool for identifying ongoing pathological processes in a kidney allograft. PATIENTS AND METHODS: The study included 40 patients who underwent a protocol biopsy within 1­year post kidney transplant. The urinary concentrations of CCL2 and CXCL10 with reference to creatinine in urine were assayed in all patients. On the basis of biopsy results, a study group was selected (n = 25), including patients with a diagnosis of interstitial fibrosis and tubular atrophy grades II to III (n = 16), BK virus (BKV) nephropathy (n = 4), or mild inflammatory lesions fulfilling the criteria for mild rejection processes or borderline lesions (n = 11). Patients with normal biopsy results were included in a control group (n = 15). RESULTS: The ratio of CCL2 to creatinine (CCL2:Cr) was a significant independent predictor of BKV ephropathy (odds ratio, 1.1; 95% CI, 1.0-1.2; P = 0.04). The CXCL10:Cr ratio was not found to be an independent predictor of BKV nephropathy (odds ratio, 1.3; 95% CI, 0.99-1.71; P = 0.06). CONCLUSIONS: The CCL2:Cr and CXCL10:Cr ratios may predict BKV nephropathy. The diagnostic value of CCL2 and CXCL10 in BKV infection should be further evaluated.

Killer Immunoglobulin-Like Receptor 2DS2 (KIR2DS2), KIR2DL2-HLA-C1, and KIR2DL3 as Genetic Markers for Stratifying the Risk of Cytomegalovirus Infection in Kidney Transplant Recipients.

Infection with cytomegalovirus (CMV) remains a major problem in kidney transplant recipients, resulting in serious infectious complications and occasionally mortality. Accumulating evidence indicates that natural killer cell immunoglobulin-like receptors (KIRs) and their ligands affect the susceptibility to various diseases, including viral infections (e.g., CMV infection). We investigated whether KIR genes and their ligands affect the occurrence of CMV infection in a group of 138 kidney transplant recipients who were observed for 720 days posttransplantation. We typed the recipients for the presence of KIR genes (human leukocyte antigen C1 [HLA-C1], HLA-C2, HLA-A, HLA-B, and HLA-DR1) by polymerase chain reaction with sequence-specific primers. The multivariate analysis revealed that the lack of KIR2DS2 (p = 0.035), the presence of KIR2DL3 (p = 0.075), and the presence of KIR2DL2⁻HLA-C1 (p = 0.044) were risk factors for posttransplant CMV infection. We also found that a lower estimated glomerular filtration rate (p = 0.036), an earlier time of antiviral prophylaxis initiation (p = 0.025), lymphocytopenia (p = 0.012), and pretransplant serostatus (donor-positive/recipient-negative; p = 0.042) were independent risk factors for posttransplant CMV infection. In conclusion, our findings confirm that the KIR/HLA genotype plays a significant role in anti-CMV immunity and suggest the contribution of both environmental and genetic factors to the incidence of CMV infection after kidney transplantation.

Diagnostic utility of monitoring cytomegalovirus-specific immunity by QuantiFERON-cytomegalovirus assay in kidney transplant recipients.

BACKGROUND: Despite universal prophylaxis, late cytomegalovirus (CMV) infection occurs in a high proportion of kidney transplant recipients. We evaluated whether a specific viral T-cell response allows for the better identification of recipients who are at high risk of CMV infection after prophylaxis withdrawal. METHODS: We conducted a prospective study in 19 pretransplant anti-CMV seronegative kidney graft recipients R- (18 from seropositive donors [D+] and one from a seronegative donor [D-]) and 67 seropositive recipients R(+) (59 from seropositive donors and eight from seronegative donors) who received antiviral prophylaxis with valganciclovir. The QuantiFERON-CMV (QF-CMV) assay was performed within the first and third months after transplantation. Blood samples were monitored for CMV DNAemia using a commercial quantitative nucleic acid amplification test (QNAT) that was calibrated to the World Health Organization International Standard. RESULTS: Twenty-one of the 86 patients (24%) developed CMV viremia after prophylaxis withdrawal within 12 months posttransplantation. In the CMV R(+) group, the QF-CMV assay yielded reactive results (QF-CMV[+]) in 51 of 67 patients (76%) compared with 7 of 19 patients (37%) in the CMV R(-) group (p = 0.001). In the CMV R(+) group, infection occurred in seven of 16 recipients (44%) who were QF-CMV(-) and eight of 51 recipients (16%) who were QF-CMV(+). In the CMV R(-) group, infection evolved in five of 12 recipients (42%) who were QF-CMV(-) and one of 7 recipients (14%) who were QF-CMV(+). No difference was found in the incidence of CMV infection stratified according to the QF-CMV results with regard to the recipients' pretransplant CMV IgG serology (p = 0.985). Cytomegalovirus infection occurred in 15 of 36 patients (42%) with hypogammaglobulinemia (HGG) 90 days posttransplantation compared with two of 34 patients (6%) without HGG (p = 0.0004). Cytomegalovirus infection occurred in seven of 13 patients (54%) with lymphocytopenia compared with 14 of 70 patients (20%) without lymphocytopenia (p = 0.015). The multivariate analysis revealed that the nonreactive QuantiFERON-CMV assay was an independent risk factor for postprophylaxis CMV infection. CONCLUSIONS: In kidney transplant recipients who received posttransplantation prophylaxis, negative QF-CMV results better defined the risk of CMV infection than initial CMV IgG status after prophylaxis withdrawal. Hypogammaglobulinemia and lymphocytopenia were risk factors for CMV infection.

The current management of kidney disease in the elderly.

Chronic kidney disease (CKD), diabetes and cardiovascular disease constitute three interrelated conditions of strong public health relevance. Elderly individuals account for the largest and the most rapidly growing age segment of the end-stage renal disease population. The elderly are affected by the same types of kidney diseases as younger individuals, but aging itself is associated with a gradual reduction in estimated glomerular filtration rate, which leads to the diminishment of the functional reserve and makes an individual more vulnerable to injurious effects of hypertension, cardiovascular disease, diabetes, and drugs' toxicity. Although the spectrum of diseases affecting people aged ≥65 is the same as in younger population, there are some distinct differences in the frequency of certain nephropathies between these two age groups. The superimposition of aging-related lesions on other kidney diseases evolving in the elderly population makes the clinical picture more complex and reaching diagnosis more challenging. In elderly CKD patients the high prevalence of comorbidities and the often aberrant metabolism of medications have to be considered in individually tailored treatment strategies.

Clinicopathologic correlations of renal pathology in the adult population of Poland.

BACKGROUND: This is the first report on the epidemiology of biopsy-proven kidney diseases in Poland. METHODS: The Polish Registry of Renal Biopsies has collected information on all (n = 9394) native renal biopsies performed in Poland from 2009 to 2014. Patients' clinical data collected at the time of biopsy, and histopathological diagnoses were used for epidemiological and clinicopathologic analysis. RESULTS: There was a gradual increase in the number of native renal biopsies performed per million people (PMP) per year in Poland in 2009-14, starting from 36 PMP in 2009 to 44 PMP in 2014. A considerable variability between provinces in the mean number of biopsies performed in the period covered was found, ranging from 5 to 77 PMP/year. The most common renal biopsy diagnoses in adults were immunoglobulin A nephropathy (IgAN) (20%), focal segmental glomerulosclerosis (FSGS) (15%) and membranous glomerulonephritis (MGN) (11%), whereas in children, minimal change disease (22%), IgAN (20%) and FSGS (10%) were dominant. Due to insufficient data on the paediatric population, the clinicopathologic analysis was limited to patients ≥18 years of age. At the time of renal biopsy, the majority of adult patients presented nephrotic-range proteinuria (45.2%), followed by urinary abnormalities (38.3%), nephritic syndrome (13.8%) and isolated haematuria (1.7%). Among nephrotic patients, primary glomerulopathies dominated (67.6% in those 18-64 years of age and 62.4% in elderly patients) with leading diagnoses being MGN (17.1%), FSGS (16.2%) and IgAN (13.0%) in the younger cohort and MGN (23.5%), amyloidosis (18.8%) and FSGS (16.8%) in the elderly cohort. Among nephritic patients 18-64 years of age, the majority (55.9%) suffered from primary glomerulopathies, with a predominance of IgAN (31.3%), FSGS (12.7%) and crescentic GN (CGN) (11.1%). Among elderly nephritic patients, primary and secondary glomerulopathies were equally common (41.9% each) and pauci-immune GN (24.7%), CGN (20.4%) and IgAN (14.0%) were predominant. In both adult cohorts, urinary abnormalities were mostly related to primary glomerulopathies (66.8% in younger and 50% in elderly patients) and the leading diagnoses were IgAN (31.4%), FSGS (15.9%), lupus nephritis (10.7%) and FSGS (19.2%), MGN (15.1%) and pauci-immune GN (12.3%), respectively. There were significant differences in clinical characteristics and renal biopsy findings between male and female adult patients. CONCLUSIONS: The registry data focused new light on the epidemiology of kidney diseases in Poland. These data should be used in future follow-up and prospective studies.

Kidney disease in the elderly: biopsy based data from 14 renal centers in Poland.

BACKGROUND: Longer life expectancy is associated with an increasing prevalence of kidney disease. Aging itself may cause renal damage, but the spectrum of kidney disorders that affect elderly patients is diverse. Few studies, mostly form US, Asia and West Europe found differences in the prevalence of some types of kidney diseases between elderly and younger patients based on renal biopsy findings, with varied proportion between glomerulopathies and arterionephrosclerosis as a dominant injury found. Here, for the first time in Eastern Europe we analyzed native kidney biopsy findings and their relationship to clinical characteristics at the time of biopsy in elderly individuals (aged ≥65) in comparison to younger adults (aged 18-64). METHODS: Biopsy and clinical data from 352 patients aged ≥65 were retrospectively identified, analyzed and compared with a control group of 2214 individuals aged 18-64. All kidney biopsies studied were examined at Medical University of Warsaw in years 2009-14. RESULTS: In elderly patients the leading indication for biopsy was nephrotic range proteinuria without hematuria (34.2%) and the most prevalent pathologic diagnoses were: membranous glomerulonephritis (MGN) (18.2%), focal segmental glomerulosclerosis (FSGS) (17.3%) amyloidosis (13.9%) and pauci immune glomerulonephritis (12.8%). Hypertension and age-related lesions very rarely were found an exclusive or dominant finding in a kidney biopsy (1.7%) and a cause of proteinuria (1.1%) in elderly individuals. There were 18.2% diabetics among elderly individuals, and as much as 75% of them had no morphologic signs of diabetic kidney disease in the renal biopsy. Amyloidosis, MGN, pauci immune GN, crescentic GN and light and/or heavy chain deposition disease (LCDD/HCDD) were more frequent whereas IgA nephropathy (IgAN), lupus nephritis (LN) and thin basement membrane disease (TBMD) were less common among elderly than in younger patients. CONCLUSIONS: Proteinuria, a dominating manifestation in elderly patients subjected to kidney biopsy was most commonly related to glomerulopathies. The relatively high prevalence of potentially curative kidney diseases in elderly individuals implicates the importance of renal biopsy in these patients.

Severe cytomegalovirus infection in a second kidney transplant recipient treated with ganciclovir, leflunomide, and immunoglobulins, with complications including seizures, acute HCV infection, drug-induced pancytopenia, diabetes, cholangitis, and multi-organ failure with fatal outcome: a case report.

BACKGROUND: Cytomegaly remains one of the most common infectious complications in organ transplant recipients, and the course of the infection may have a negative effect on survival of the transplant and recipient. CASE REPORT: We describe the case of a 32-year-old female patient who received a second kidney transplant from a cadaveric donor in July 2012, treated successfully with ganciclovir for primary CMV infection in August 2012 and then re-treated from November due to re-infection. The viral load at the start of re-treatment was 6 million copies. In view of ganciclovir treatment failure, Sando immunoglobulins were administered. Subsequently, when CMV viral load increased to 18 million copies, a decision was made to use combination treatment with leflunomide and ganciclovir. Immunosuppressive treatment was also modified by administering everolimus in view of its potential antiviral activity. Seizures, pancytopenia, diabetes, diarrhoea, and (probably) drug-induced liver damage and cholangitis were observed in the course of treatment. At 3 months of hospitalization, the patient was discharged home with viral load of 8000 copies. As treatment continuation, she received valganciclovir at the full therapeutic dose in view of very good kidney function (creatinine 0.7 mg/dl). The patient was re-hospitalized after 10 days due to fever and cough. Due to abnormal liver function test results and negative serum markers of viral hepatitis, HCV RNA was tested, with a positive result (above 10^8 copies). Subsequently, decline in clinical status, overhydration, increasing creatinine levels, hepatic failure signs, and renewed CMV DNA increase to 520 000 copies were observed. Despite intensive treatment, the patient died of multi-organ failure. CONCLUSIONS: The case described illustrates the difficulties in the treatment of CMV infection and its possible dramatic complications.

[Human herpes virus 6 infection in renal transplant recipient--case report]. / Zakazenie ludzkim wirusem herpes typu 6 u biorcy alloprzeszczepu nerki--opis przypadku.

Human herpesvirus 6 (HHV-6) is a lymphotropic herpesvirus of emerging clinical significance in immunocompromised patients. Little is known about clinical impact and relevance of HHV-6 variant A infection in renal transplant recipients. We describe the case of a 44-year-old woman who underwent second allogenic kidney transplantation (Tx). On day 6 after Tx she presented with high fever. She developed thrombocytopenia, anemia, diarrhea, liver dysfunction and graft failure. Renal graft biopsies that followed revealed acute rejection. Apart from the introduction of anti-rejection therapy, empiric gancyclovir, as well as antibacterial treatment was initiated. To determine the serostatus of HHV-6 and load of HHV-6A and -6B DNA in paired sera samples an enzyme-linked immunosorbent assay, indirect immunofluorescence assay and real time quantitative polymerase chain reaction (PCR) assay based on the exonuclease format (TaqMan) was devised. HHV-6A was the sole pathogen, the DNA of which was retrospectively detected in patient's serum. HHV-6 IgM seroconversion was demonstrated. No other viral (e.g. cytomegalovirus (CMV)) or other pathogens were detected in the blood, urine, and stool. Following therapy with gancyclovir, viral load declined to undetectable levels. Gradual improvement in clinical status of the patient was observed. HHV-6 infection may be associated with specific clinical manifestations and should be considered in a transplant recipient who presents with a clinical syndrome resembling CMV infection, where CMV assays are negative. This case confirm symptomatic HHV-6 infection and suggests that HHV-6 variant A reactivation may potentially trigger graft rejection.