Nina Singh

CMV-specific T cells, NK cells, and neutralizing antibodies (nAbs) were assessed in a randomized trial of CMV prevention with preemptive antiviral therapy (PET) versus prophylactic antiviral therapy (PRO) in donor-seropositive/recipient-seronegative (D ⁺ R ^– ) liver transplant recipients (LTxR) at 100 days (end of intervention) and at 6 and 12 months after transplant. The PET group had significantly increased numbers of circulating polyfunctional T cells, NK cells, and nAbs compared with the PRO group at day 100, and several CMV immune parameters remained significantly higher by 12 months after transplant. Among PET recipients, preceding CMV viremia (vs. no preceding viremia) was associated with significantly higher levels of most CMV immune parameters at day 100. Higher numbers of CMV-specific polyfunctional T cells and NKG2C ⁺ NK cells at day 100 were associated with a decreased incidence of CMV disease in multivariable Cox regression. The strongest associations with protection against CMV disease were with increased numbers of CMV-specific polyfunctional CD4 ⁺ T cells, CD3 ^neg CD56 ^dim CD57 ^neg NKG2C ^pos cells, and CD3 ^neg CD56 ^dim CD57 ^pos NKG2C ^pos NK cells. Our results suggest that PET is superior to PRO for CMV disease prevention by allowing low-level CMV replication and associated antigen exposure that is promptly controlled by antiviral therapy and facilitates enhanced CMV protective immunity in D ⁺ R ^– LTxR.

Background: Whether donor (D+) or recipient (R+) cytomegalovirus (CMV) seropositivity is associated with functional impairment in liver transplant recipients is not known. Methods: Patients included adult liver transplant recipients in the Organ Procurement and Transplantation Network database transplanted over a five-year period from 1 January 2014–31 December 2018. Functional status in the database was assessed using Karnofsky performance scale. A logistic regression model that controlled for potential confounders was used to examine the association of CMV serostatus and functional status. Variables significantly associated with functional status (p < 0.05) were then used to develop propensity score and propensity score matched analysis was conducted where each patient was compared with a matched-control with the same propensity score. Results: Among 30,267 adult liver transplant recipients, D+ or R+ patients had significantly lower functional status at last follow-up than the D-R- cohort (OR 0.88, 95% CI 0.80–0.96, p = 0.007). In propensity score matched model, D+ or R+ patients had significantly lower functional status than matched-controls (p = 0.009). D+ or R+ CMV serostatus (p = 0.018) and low functional level (p < 0.001) were also independently associated with infections as cause-of-death. Conclusions: D+ or R+ liver transplant recipients had lower functional status and higher risk of deaths due to infections. Future studies are warranted to examine the mechanistic basis of these findings in the setting of transplantation.

Detailed cytomegalovirus (CMV) kinetics in donor CMV-seropositive, recipient CMV-seronegative (D⁺/R^–) transplant recipients receiving preemptive therapy (PET) have not been fully defined. The study population consisted of the PET arm of a randomized CMV prevention trial in D⁺/R^– liver transplant recipients. CMV DNA polymerase chain reaction (PCR) assays were performed weekly for 100 days using a sensitive assay. Viral load and clinical parameters were compared for patients with or without high-level increase (defined as higher than the group median log₁₀ increase in viral load from baseline after PET initiation). Among 79 patients, 93.6% (74/79) developed an increase from baseline viral loads of median 120 IU/mL to 3350 IU/mL; 25.7% (19/74) of the patients had peak levels >10 000 IU/mL. None of the patients with rise in viral load underwent testing for CMV resistance, and viremia resolved with PET with valganciclovir. Patients with high-level increase in viral load had a significantly lower rate of recurrent viremia than those without such increase (16/40 [40%] vs 28/39 [71.8%], respectively; P = .004). A majority of D⁺/R^– recipients had a marked increase in viral load after initiation of PET before resolution of viremia. This phenomenon is associated with lower rates of subsequent recurrent viremia and does not necessarily imply antiviral resistance.

Background.: Risk factors, virological parameters, and outcomes associated with HHV-6 viremia in high-risk donor CMV-seropositive and recipient CMV-seronegative (D+R–) liver transplant recipients in the current era are incompletely defined. Methods.: The study population consisted of patients in the preemptive therapy (PET) arm of a randomized, controlled trial of PET versus valganciclovir prophylaxis for CMV prevention in D+R– liver transplant recipients. Weekly blood samples through 100 d in the PET group were tested for HHV-6 viremia using a real-time quantitative polymerase chain reaction. Assessments included virological characteristics and relationship with CMV, risk factors, and impact of HHV-6 viremia with outcomes through 12 mo posttransplant. Results.: HHV-6 viremia at any level developed in 42% (40 of 96). Older patient age (P = 0.03), longer hospitalization (P = 0.015), and ICU stay at transplantation (P = 0.029) were significantly associated with high-grade viremia. Concurrent HHV-6 and CMV viremia was associated with earlier onset of HHV-6 viremia (P = 0.004), higher HHV-6 area under the curve (P = 0.043), and higher peak HHV-6 viral load (P = 0.006) versus HHV-6 viremia alone. High-grade viremia was independently associated with biopsy-proven rejection within 12 mo (P = 0.045) posttransplant. Conclusions.: Among D+R– liver transplant recipients receiving valganciclovir as PET, high-grade HHV-6 viremia was associated with increased age and critical illness in ICU at time of transplant and was independently associated with allograft rejection.

The risk factors for development of viremia in high-risk donor cytomegalovirus (CMV)-seropositive and recipient CMV-seronegative (D⁺R⁻) transplant recipients are incompletely defined. The study population comprised patients in the preemptive therapy (PET) arm of a randomized, controlled trial of PET versus prophylaxis using valganciclovir in D⁺R⁻ liver transplant recipients. Weekly surveillance monitoring for viremia for 100 days was performed using a sensitive CMV-DNA polymerase chain reaction assays. Risk factors for viremia and time to onset (≤4 vs >4 weeks) of viremia were examined using logistic regression models. Viremia developed in 84% (79/94) of recipients and older donor age was the only independent factor associated with viremia (odds ratio, 2.20 for each quartile increase in donor age; 95% confidence interval [CI], 1.07–4.52; P = .031). Recipients who developed early-onset viremia (within 4 weeks) also had significantly older donors than those with later-onset viremia (difference in age 10.1 years; 95% CI, 2–19; P = .03). Older donor age was an independent predictor of viremia and earlier-onset of viremia in D⁺R⁻ liver transplant recipients. Future studies should assess the mechanistic links underlying this novel association. NCT01552369.

The relative costs of preemptive therapy (PET) or prophylaxis for the prevention of cytomegalovirus (CMV) disease in high-risk donor CMV-seropositive/recipient-seronegative (D⁺/R⁻) liver transplant recipients have not been assessed in the context of a randomized trial. A decision tree model was constructed based on the probability of outcomes in a randomized controlled trial that compared valganciclovir as PET or prophylaxis for 100 days in 205 D⁺/R⁻ liver transplant recipients. Itemized costs for each site were obtained from a federal cost transparency database. Total costs included costs of implementation of the strategy and CMV disease treatment-related costs. Net cost per patient was estimated from the decision tree for each strategy. PET was associated with a 10% lower absolute rate of CMV disease (9% vs 19%). The cost of treating a case of CMV disease in our patients was $88 190. Considering cost of implementation of strategy and treatment-related cost for CMV disease, the net cost-savings per patient associated with PET was $8707 compared to prophylaxis. PET remained cost-effective across a range of assumptions (varying costs of monitoring and treatment, and rates of disease). PET is the dominant CMV prevention strategy in that it was associated with lower rates of CMV disease and lower overall costs compared to prophylaxis in D⁺/R⁻ liver transplant recipients. Costs were driven primarily by more hospitalizations and higher CMV disease–associated costs due to delayed onset postprophylaxis disease in the prophylaxis group.

Importance Despite the use of a cytomegalovirus (CMV) prevention strategy of antiviral prophylaxis for high-risk CMV-seronegative liver transplant recipients with seropositive donors, high rates of delayed-onset postprophylaxis CMV disease occur. An alternate approach, preemptive therapy (initiation of antiviral therapy for early asymptomatic CMV viremia detected by surveillance testing), has not previously been directly compared with antiviral prophylaxis in these patients. Objective To compare preemptive therapy with antiviral prophylaxis in CMV-seronegative liver transplant recipients with seropositive donors for the prevention of CMV disease. Design, Setting, and Participants Randomized clinical trial of preemptive therapy vs antiviral prophylaxis in 205 CMV-seronegative liver transplant recipients with seropositive donors aged older than 18 years. The trial was conducted at 6 academic transplant centers in the United States between October 2012 and June 2017, with last follow-up in June 2018. Interventions Patients were randomized 1:1 to receive either preemptive therapy (valganciclovir, 900 mg, twice daily until 2 consecutive negative tests a week apart) for viremia detected by weekly plasma CMV polymerase chain reaction for 100 days (n = 100) or valganciclovir, 900 mg, daily for 100 days as antiviral prophylaxis (n = 105). Main Outcomes and Measures The primary outcome was incidence of CMV disease by 12 months, defined as CMV syndrome (CMV viremia and clinical or laboratory findings) or end-organ disease. Secondary outcomes included acute allograft rejection, opportunistic infections, graft and patient survival, and neutropenia. Results Among 205 patients who were randomized (mean age, 55 years; 62 women [30%]), all 205 (100%) completed the trial. The incidence of CMV disease was significantly lower with preemptive therapy than antiviral prophylaxis (9% [9/100] vs 19% [20/105]; difference, 10% [95% CI, 0.5% to 19.6%];P = .04]). The incidence of allograft rejection (28% vs 25%; difference, 3% [95% CI, −9% to 15%]), opportunistic infections (25% vs 27%; difference, 2% [95% CI, −14% to 10%]), graft loss (2% vs 2%; difference, P = .46). Conclusions and Relevance Among CMV-seronegative liver transplant recipients with seropositive donors, the use of preemptive therapy, compared with antiviral prophylaxis, resulted in a lower incidence of CMV disease over 12 months. Further research is needed to replicate these findings and assess long-term outcomes. Trial Registration ClinicalTrials.gov Identifier:NCT01552369

Nina Singh; Unique Rarity of Tuberculosis and Granulomatous Opportunistic Infections in Hematopoietic Cell Transplant Recipients, Clinical Infectious Diseases,