Respiratory Syncytial Virus, Human Metapneumovirus, and Parainfluenza Virus Infections in Lung Transplant Recipients: A Systematic Review of Outcomes and Treatment Strategies.

BACKGROUND: Respiratory syncytial virus (RSV), parainfluenza virus (PIV), and human metapneumovirus (hMPV) are increasingly associated with chronic lung allograft dysfunction (CLAD) in lung transplant recipients (LTR). This systematic review primarily aimed to assess outcomes of RSV/PIV/hMPV infections in LTR and secondarily to assess evidence regarding the efficacy of ribavirin. METHODS: Relevant databases were queried and study outcomes extracted using a standardized method and summarized. RESULTS: Nineteen retrospective and 12 prospective studies were included (total 1060 cases). Pooled 30-day mortality was low (0-3%), but CLAD progression 180-360 days postinfection was substantial (pooled incidences 19-24%) and probably associated with severe infection. Ribavirin trended toward effectiveness for CLAD prevention in exploratory meta-analysis (odds ratio [OR] 0.61, [0.27-1.18]), although results were highly variable between studies. CONCLUSIONS: RSV/PIV/hMPV infection was followed by a high CLAD incidence. Treatment options, including ribavirin, are limited. There is an urgent need for high-quality studies to provide better treatment options for these infections.

Impact of COVID-19 social distancing measures on lung transplant recipients: decline in overall respiratory virus infections is associated with stabilisation of lung function.

BACKGROUND: Coronavirus disease 2019 (COVID-19) social distancing measures led to a dramatic decline in non-COVID-19 respiratory virus infections, providing a unique opportunity to study their impact on annual forced expiratory volume in 1 s (FEV1) decline, episodes of temporary drop in lung function (TDLF) suggestive of infection and chronic lung allograft dysfunction (CLAD) in lung transplant recipients (LTRs). METHODS: All FEV1 values of LTRs transplanted between 2009 and April 2020 at the University Medical Center Groningen (Groningen, The Netherlands) were included. Annual FEV1 change was estimated with separate estimates for pre-social distancing (2009-2020) and the year with social distancing measures (2020-2021). Patients were grouped by individual TDLF frequency (frequent/infrequent). Respiratory virus circulation was derived from weekly hospital-wide respiratory virus infection rates. Effect modification by TDLF frequency and respiratory virus circulation was assessed. CLAD and TDLF rates were analysed over time. RESULTS: 479 LTRs (12 775 FEV1 values) were included. Pre-social distancing annual change in FEV1 was -114 (95% CI -133- -94) mL, while during social distancing FEV1 did not decline: 5 (95% CI -38-48) mL (difference pre-social distancing versus during social distancing: p<0.001). The frequent TDLF subgroup showed faster annual FEV1 decline compared with the infrequent TDLF subgroup (-150 (95% CI -181- -120) versus -90 (95% CI -115- -65) mL; p=0.003). During social distancing, we found significantly lower odds for any TDLF (OR 0.53, 95% CI 0.33-0.85; p=0.008) and severe TDLF (OR 0.34, 0.16-0.71; p=0.005) as well as lower CLAD incidence (OR 0.53, 95% CI 0.27-1.02; p=0.060). Effect modification by respiratory virus circulation indicated a significant association between TDLF/CLAD and respiratory viruses. CONCLUSIONS: During COVID-19 social distancing the strong reduction in respiratory virus circulation coincided with markedly less FEV1 decline, fewer episodes of TDLF and possibly less CLAD. Effect modification by respiratory virus circulation suggests an important role for respiratory viruses in lung function decline in LTRs.

Longitudinal monitoring of BKPyV miRNA levels in kidney transplant recipients with BKPyV-related pathology reflects viral DNA levels and remain high in viremia patients after clearance of viral DNA.

INTRODUCTION: It is unclear whether polyomavirus BK (BKPyV) microribonucleic acid (miRNA) measurement has additional diagnostic and predictive value in kidney transplant recipients (KTR) as compared to current methods of monitoring BKPyV DNA loads. PATIENTS AND METHODS: A retrospective, longitudinal study was performed in 30 KTR with BKPyV viruria (n = 10), BKPyV viremia (n = 10), or BKPyV-associated neuropathy (BKPyVAN) (n = 10). Bkv-miR-B1-3p and 5p and BKPyV DNA load were measured in urine and plasma and compared using receiver operating characteristic (ROC) curves. RESULTS: Levels of Bkv-miR-B1-3p and 5p and BKPyV DNA correlated strongly. Overall, mostly analog courses of urinary and plasma miRNA and DNA loads were observed. Areas under the ROC curves were not significantly different between miRNAs and DNA. Only, in contrast to BKPyV DNA load, BKPyV miRNA levels increased from 6 to 12 months in the viremia group, while in the BKPyVAN group, a decline was seen in both DNA and miRNA. CONCLUSIONS: In this study, we could not demonstrate an additional value of BKPyV miRNA detection compared to BKPyV DNA monitoring in the early phase after kidney transplantation. We did observe significant differences between the viremia and the BKPyVAN groups during follow-up. This study was performed with a small number of patients and therefore results should be verified in a larger patient cohort. Furthermore, future studies with larger patient groups are necessary to elucidate final clinical value of these data.

Ribavirin for Hepatitis E Virus Infection After Organ Transplantation: A Large European Retrospective Multicenter Study.

BACKGROUND: Ribavirin is currently recommended for treating chronic hepatitis E virus (HEV) infection. This retrospective European multicenter study aimed to assess the sustained virological response (SVR) in a large cohort of solid organ transplant (SOT) recipients with chronic HEV infection treated with ribavirin monotherapy (N = 255), to identify the predictive factors for SVR, and to evaluate the impact of HEV RNA mutations on virological response. METHODS: Data from 255 SOT recipients with chronic HEV infection from 30 European centers were analyzed. Ribavirin was given at the median dose of 600 (range, 29-1200) mg/day (mean, 8.6 ± 3.6 mg/kg/day) for a median duration of 3 (range, 0.25-18) months. RESULTS: After a first course of ribavirin, the SVR rate was 81.2%. It increased to 89.8% when some patients were offered a second course of ribavirin. An increased lymphocyte count at the initiation of therapy was a predictive factor for SVR, while poor hematological tolerance of ribavirin requiring its dose reduction (28%) and blood transfusion (15.7%) were associated with more relapse after ribavirin cessation. Pretreatment HEV polymerase mutations and de novo mutations under ribavirin did not have a negative impact on HEV clearance. Anemia was the main adverse event. CONCLUSIONS: This large-scale retrospective study confirms that ribavirin is highly efficient for treating chronic HEV infection in SOT recipients and shows that the predominant HEV RNA polymerase mutations found in this study do not affect the rate of HEV clearance.This large-scale retrospective study that included 255 solid organ transplant recipients confirms that ribavirin is highly efficient for treating chronic hepatitis E virus (HEV) infection and shows that HEV RNA polymerase mutations do not play a role in HEV clearance.

Evaluation of 10 years of parainfluenza virus, human metapneumovirus, and respiratory syncytial virus infections in lung transplant recipients.

Respiratory tract infection with pneumoviruses (PVs) and paramyxoviruses (PMVs) are increasingly associated with chronic lung allograft dysfunction (CLAD) in lung transplant recipients (LTRs). Ribavirin may be a treatment option but its effectiveness is unclear, especially with respect to infection severity. We retrospectively analyzed 10 years of PV/PMV infections in LTRs. The main end points were forced expiratory volume in 1 second (FEV1 ) at 3 and 6 months postinfection, expressed as a percentage of pre-infection FEV1 and incidence of new or progressed CLAD 6 months postinfection. A total of 139 infections were included: 88 severe infections (63%) (defined as >10% FEV1 loss at infection) and 51 mild infections (37%) (≤10% FEV1 loss). Overall postinfection CLAD incidence was 20%. Associations were estimated on postinfection FEV1 for ribavirin vs no ribavirin (+13.2% [95% CI: 7.79; 18.67]) and severe vs mild infection (-11.1% [95% CI: -14.76; -7.37]). Factors associated with CLAD incidence at 6 months were ribavirin treatment (odds ratio (OR [95% CI]) 0.24 [0.10; 0.59]), severe infection (OR [95% CI] 4.63 [1.66; 12.88]), and mycophenolate mofetil use (OR [95% CI] 0.38 [0.14; 0.97]). These data provide valuable information about the outcomes of lung transplant recipients with these infections and suggests possible associations of ribavirin use and infection severity with long-term outcomes. Well-designed prospective trials are needed to confirm these findings.

Rapid Molecular Tests for Influenza, Respiratory Syncytial Virus, and Other Respiratory Viruses: A Systematic Review of Diagnostic Accuracy and Clinical Impact Studies.

We systematically reviewed available evidence from Embase, Medline, and the Cochrane Library on diagnostic accuracy and clinical impact of commercially available rapid (results <3 hours) molecular diagnostics for respiratory viruses as compared to conventional molecular tests. Quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies criteria for diagnostic test accuracy (DTA) studies, and the Cochrane Risk of Bias Assessment and Risk of Bias in Nonrandomized Studies of Interventions criteria for randomized and observational impact studies, respectively. Sixty-three DTA reports (56 studies) were meta-analyzed with a pooled sensitivity of 90.9% (95% confidence interval [CI], 88.7%-93.1%) and specificity of 96.1% (95% CI, 94.2%-97.9%) for the detection of either influenza virus (n = 29), respiratory syncytial virus (RSV) (n = 1), influenza virus and RSV (n = 19), or a viral panel including influenza virus and RSV (n = 14). The 15 included impact studies (5 randomized) were very heterogeneous and results were therefore inconclusive. However, we suggest that implementation of rapid diagnostics in hospital care settings should be considered.

Population pharmacokinetics of ribavirin in lung transplant recipients and examination of current and alternative dosing regimens.

BACKGROUND: Ribavirin is used in the treatment of respiratory paramyxovirus infection in lung transplant recipients; however, its pharmacokinetic profile in the transplant population is unknown despite the potential for alterations due to underlying pathology. Furthermore, the ability of current regimens to meet exposure targets has not been established. OBJECTIVES: This study examined the pharmacokinetics of ribavirin in a lung transplant population for which current and alternative dosing regimens were assessed. METHODS: Population pharmacokinetic modelling was conducted in NONMEM using concentration-time data from 24 lung transplant recipients and 6 healthy volunteers. Monte Carlo simulation was used to assess the ability of dosing regimens to achieve pre-specified target concentrations. RESULTS AND CONCLUSIONS: A three-compartment model with first-order elimination most adequately described ribavirin concentration-time data, with CLCR and patient type (i.e. lung transplant) identified as significant covariates in the model. Simulations indicate that current regimens achieve efficacious concentrations within 24 h of treatment initiation that increase to supra-therapeutic levels over the treatment period. A regimen of 8 mg/kg q6h orally for 48 h followed by 8 mg/kg q24h orally for the remainder of the treatment period was predicted to result in >90% of patients exhibiting concentrations within the defined target range throughout the entire treatment course. Additional work to formally establish target therapeutic concentrations is required; however, this study provides a valuable first step in determining optimal ribavirin treatment regimens for paramyxovirus infections in the lung transplant population.

Primary Polyomavirus Infection, Not Reactivation, as the Cause of Trichodysplasia Spinulosa in Immunocompromised Patients.

Classic human polyomaviruses (JC and BK viruses) become pathogenic when reactivating from latency. For the rare skin disease trichodysplasia spinulosa, we show that manifestations of the causative polyomavirus (TSPyV) occur during primary infection of the immunosuppressed host. High TSPyV loads in blood and cerebrospinal fluid, sometimes coinciding with cerebral lesions and neuroendocrine symptoms, marked the acute phase of trichodysplasia spinulosa, whereas initiation and maturation of TSPyV seroresponses occurred in the convalescent phase. TSPyV genomes lacked the rearrangements typical for reactivating polyomaviruses. These findings demonstrate the clinical importance of primary infection with this rapidly expanding group of human viruses and explain the rarity of some novel polyomavirus-associated diseases.

High human cytomegalovirus DNAemia early post-transplantation associates with irreversible and progressive loss of renal function - a retrospective study.

Transplant recipients are prone to viral infections, which could affect renal transplantation outcome. Our aim was to assess the effects of early human cytomegalovirus (CMV) DNAemia on transplant renal function. A total of 264 (age 50.9 ± 13.5; male 55%) renal transplantation recipients undergoing preemptive anti-CMV therapy were retrospectively categorized based on early (<3 months post-Tx) CMV peak viral load (PVL); PVL ≤ 536, PVL536-6310, or PVL > 6310 International Units/ml (IU/ml). Estimated glomerular filtration rate (eGFR) was analyzed between 1 and 36 months post-transplantation with Kruskal-Wallis test, linear regression, and a linear mixed-effects model. CMV infection was detectable in 113 (43%) recipients within 49 [38-67] days. Subjects with PVL > 6310 had statistically significant ~5-13 ml/min lower eGFR between 3 and 36 months compared to PVL ≤ 536 and PVL536-6310. eGFR declined from 46.1 to 40.7 ml/min/1.73 m2 (-12%) over 3 years, and the annual decrease for pronounced infection with high PVL was 2.0 ml/min/1.73 m2 faster than for noninfected or mildly infected subjects. In conclusion, high CMV DNAemia early after renal transplantation was associated with significant loss of renal function, from which subjects did not recover. The severity of infection (high PVL early post-transplantation), more than the infection per se, was related to irreversible and progressive loss of renal function.

Incidence and outcome of BK polyomavirus infection in a multicenter randomized controlled trial with renal transplant patients receiving cyclosporine-, mycophenolate sodium-, or everolimus-based low-dose immunosuppressive therapy.

BACKGROUND: It remains unclear whether overall degree of immunosuppression or specific effects of individual immunosuppressive agents are causal for increased occurrence of BK polyomavirus (BKPyV) infection in renal transplant recipients (RTR). METHODS: A prospective, multicenter, open-label randomized controlled trial in 361 de novo RTR was performed. A total of 224 RTR were randomized at 6 months into three treatment groups with dual therapy consisting of prednisolone (Pred) plus either cyclosporine (CsA), mycophenolate sodium (MPS), or everolimus (EVL). Primary outcomes were incidence of BK viruria, BK viremia, and BKPyV-associated nephropathy (BKVAN). RESULTS: From 6 months, incidence of BK viruria in the MPS group (43.6%) was significantly higher than in the other groups (CsA: 16.9%, EVL: 19.8%) (P=.003). BKVAN was diagnosed in 3 patients, all treated with MPS (7.8%, P=.001). Longitudinal data analysis showed a lower BKPyV load and a significantly faster clearance of BK viruria in the CsA group compared to the MPS group (P=.03). CONCLUSIONS: Treatment with MPS was associated with an increased incidence of BK viruria. Dual immunosuppressive therapy with CsA and Pred was associated with the lowest rate of BKPyV replication and the fastest clearance of the virus.

Influenza Infection and Acute Myocardial Infarction.

BACKGROUND: Acute respiratory infections can trigger acute myocardial infarction. We aimed to quantify the association between laboratory-confirmed influenza infection and acute myocardial infarction, particularly in patients with and without known coronary artery disease. METHODS: This observational, registry-based, self-controlled case series study evaluated the association between laboratory-confirmed influenza infection and occurrence of acute myocardial infarction. Laboratory records on respiratory virus polymerase chain reaction (PCR) testing from 16 laboratories across the Netherlands were linked to national mortality, hospitalization, medication, and administrative registries. Influenza infection was defined as a positive PCR test result. Acute myocardial infarction was defined as a registered diagnostic code for either acute myocardial infarction hospitalization or death. Using a self-controlled case series method, we then compared the incidence of acute myocardial infarction during the risk period (days 1 to 7 after influenza infection) versus the control period (1 year before and 51 weeks after the risk period). RESULTS: Between 2008 and 2019, we identified 158,777 PCR tests for influenza in the study population; 26,221 were positive for influenza, constituting 23,405 unique influenza illness episodes. A total of 406 episodes were identified with acute myocardial infarction occurring within 1 year before and 1 year after confirmed influenza infection and were included in analysis. Twenty-five cases of acute myocardial infarction occurred during the risk period versus 394 during the control period. The adjusted relative incidence of acute myocardial infarction during the risk period compared with the control period was 6.16 (95% confidence interval [CI], 4.11 to 9.24). The relative incidence of acute myocardial infarction in individuals without prior hospitalization for coronary artery disease was 16.60 (95% CI, 10.45 to 26.37) compared with 1.43 (95% CI, 0.53 to 3.84) for those with prior admission for coronary artery disease. CONCLUSIONS: Influenza infection was associated with an increased risk of acute myocardial infarction, especially in individuals without a prior hospitalization for coronary artery disease. (Funded by the Dutch Research Council [NWO].).

Reactivation of Multidrug-Resistant HSV-1 in a Post-Allogenic Hematopoietic Stem Cell Transplant Patient: Dynamic Detection of the Rare A605V Mutation by Next-Generation Sequencing.

We present an immunocompromised patient with a multiresistant herpes simplex virus-1 reactivation with a rare mutation (A605V) in the viral DNA polymerase gene. Next-generation sequencing suggests the presence of multiple drug-resistant strains before treatment and altered ratios during treatment, affecting the clinical response to aciclovir and foscarnet.

Evolution and viral characteristics of a long-term circulating resistant HIV-1 strain in a cluster of treatment-naive patients.

BACKGROUND: Transmitted resistant HIV may revert to wild-type in the absence of drug pressure due to reduced replication capacity (RC). We observed eight therapy-naive patients infected with HIV harbouring four mutations at nucleoside reverse transcriptase inhibitor (NRTI) resistance-related positions: M41L, T69S, L210E and T215S. If partial reverted resistance patterns like these are detected at baseline, concerns for more extensive resistance in the quasispecies often directs selection of first-line combination antiretroviral therapy (cART) towards more complex regimens. METHODS: Genotypic resistance testing and phylogenetic analysis was performed using pol sequences of 400 therapy-naive patients and 1322 patients with at least one NRTI-related mutation. Reverse transcriptase (RT) genes were cloned into a reference strain and RC was investigated. RESULTS: Phylogenetic analysis showed that all eight patients are part of a transmission cluster (bootstrap value 92%). The patients resided in three distinct geographical regions and were either homosexually or heterosexually infected. Prior negative serology and analysis of base ambiguity demonstrated circulation for at least 7 years. In vivo evolution showed a mixture with wild-type (T215S/T) in only one untreated patient more than 6 years after diagnosis. The reverted resistance pattern did not confer a substantial reduction in RC compared with wild-type, explaining its persistence in vivo and long-term circulation in the population. Four patients started cART; three of them received quadruple cART. All patients showed good virological and immunological response. CONCLUSIONS: Long-term circulation transcending distinct regions and transmission groups suggests reversion occurred in previous hosts in the transmission chain. Identification of clusters using epidemiological data and active-partner tracing may broaden therapeutic options in cases of transmitted resistance.

Heterologous prime-boost immunizations with a virosomal and an alphavirus replicon vaccine.

Heterologous prime-boost immunization strategies in general establish higher frequencies of antigen-specific T lymphocytes than homologous prime-boost protocols or single immunizations. We developed virosomes and recombinant Semliki Forest virus (rSFV) as antigen delivery systems, each capable of inducing strong CTL responses in homologous prime-boost protocols. Here, we demonstrate that a heterologous prime-boost with recombinant Semliki Forest virus (rSFV) encoding a fusion protein of E6 and E7 of human papillomavirus (HPV) type 16 and virosomes containing the HPV16 E7 protein resulted in higher numbers of antigen-specific CTL in mice than homologous protocols. Evasion of vector-specific immunity appeared to play a role in establishing these high frequencies, as coinduction of vector-specific responses during the prime immunization reduced the frequency of antigen-specific CTL after a heterologous booster. However, the high numbers of CTL initially primed by the heterologous protocols did not correlate with enhanced responsiveness to in vitro antigenic stimulation, nor in improved cytolytic activity or antitumor responses in vivo compared to a homologous protocol with rSFV. This lack of correlation could not be explained by changes in numbers of regulatory T cells. However, we observed differences in the frequencies of T cell subsets within the E7-specific CD8(+) T cell population, e.g. higher frequencies of central memory T cells upon homologous immunizations compared to heterologous immunizations. The induction of central memory T cells is crucial for a cancer vaccine as these cells are known to rapidly expand upon recall stimulation. This study demonstrates that the strongly increased number of antigen-specific CTL as induced by heterologous prime-boost immunizations, often used as a proof for the enhanced efficacy of such regimes, does not necessarily equal superior functional antitumor responses.

Treatment of chronic hepatitis E in liver transplant recipients with pegylated interferon alpha-2b.

Hepatitis E virus (HEV) infections are known to run a self-limiting course. Recently, chronic hepatitis E has been described in immunosuppressed patients after solid-organ transplantation. Besides the general recommendation to lower the immunosuppressive medication in these patients, there is currently no specific treatment. We here describe the successful use of pegylated interferon alpha-2b in the treatment of 2 liver transplant recipients who suffered a chronic HEV infection for 9 years (case A) or 9 months (case B). After 4 weeks of therapy, a 2-log decrease (case A) and a 3-log decrease (case B) in the viral load were observed. In case A, who received treatment for 1 year, serum viral RNA became undetectable from week 20 onward, and serum liver enzymes normalized completely. In case B, interferon was discontinued at week 16 because of a lack of a further decline in the viral load. However, 4 weeks after the cessation of therapy, viral RNA was no longer detectable in the serum, and this was probably related to a further decline in the immunosuppressive medication. Liver tests normalized completely. In both cases, no relapse has been noted so far. We conclude that pegylated interferon alpha-2b may be useful in the treatment of chronic HEV infections in patients in whom the reduction of the immunosuppressive medication alone is not sufficient.

Broad Virus Detection and Variant Discovery in Fecal Samples of Hematopoietic Transplant Recipients Using Targeted Sequence Capture Metagenomics.

Pediatric allogeneic hematopoietic stem cell transplantation (HSCT) patients often suffer from gastro-intestinal (GI) disease caused by viruses, Graft-versus-Host Disease (GVHD) or a combination of the two. Currently, the GI eukaryotic virome of HSCT recipients remains relatively understudied, which complicates the understanding of its role in GVHD pathogenicity. As decisions regarding immunosuppressive therapy in the treatment of virus infection or GVHD, respectively, can be completely contradicting, it is crucial to better understand the prevalence and relevance of viruses in the GI tract in the HSCT setting. A real time PCR panel for a set of specific viruses widely used to diagnose the most common causes of GI viral gastroenteritis is possibly insufficient to grasp the full extent of viruses present. Therefore, we applied the targeted sequence capture method ViroCap to residual fecal samples of 11 pediatric allogeneic HSCT recipients with GI symptoms and a suspicion of GVHD, to enrich for nucleic acids of viruses that are known to infect vertebrate hosts. After enrichment, NGS was applied to broadly detect viral sequences. Using ViroCap, we were able to detect viruses such as norovirus and adenovirus (ADV), that had been previously detected using clinical diagnostic PCR on the same sample. In addition, multiple, some of which clinically relevant viruses were detected, including ADV, human rhinovirus (HRV) and BK polyomavirus (BKV). Interestingly, in samples in which specific PCR testing for regular viral GI pathogens did not result in a diagnosis, the ViroCap pipeline led to the detection of viral sequences of human herpesvirus (HHV)-7, BKV, HRV, KI polyomavirus and astrovirus. The latter was an only recently described variant and showed extensive sequence mismatches with the applied real time PCR primers and would therefore not have been detected if tested. Our results indicate that target enrichment of viral nucleic acids through ViroCap leads to sensitive and broad possibly clinically relevant virus detection, including the detection of newer variants in clinical HSCT recipient samples. As such, ViroCap could be a useful detection tool clinically, but also in studying the associations between viral presence and GVHD.