Challenging immunodominance of influenza-specific CD8+ T cell responses restricted by the risk-associated HLA-A*68:01 allomorph.

Although influenza viruses lead to severe illness in high-risk populations, host genetic factors associated with severe disease are largely unknown. As the HLA-A*68:01 allele can be linked to severe pandemic 2009-H1N1 disease, we investigate a potential impairment of HLA-A*68:01-restricted CD8+ T cells to mount robust responses. We elucidate the HLA-A*68:01+CD8+ T cell response directed toward an extended influenza-derived nucleoprotein (NP) peptide and show that only ~35% individuals have immunodominant A68/NP145+CD8+ T cell responses. Dissecting A68/NP145+CD8+ T cells in low vs. medium/high responders reveals that high responding donors have A68/NP145+CD8+ memory T cells with clonally expanded TCRαßs, while low-responders display A68/NP145+CD8+ T cells with predominantly naïve phenotypes and non-expanded TCRαßs. Single-cell index sorting and TCRαß analyses link expansion of A68/NP145+CD8+ T cells to their memory potential. Our study demonstrates the immunodominance potential of influenza-specific CD8+ T cells presented by a risk HLA-A*68:01 molecule and advocates for priming CD8+ T cell compartments in HLA-A*68:01-expressing individuals for establishment of pre-existing protective memory T cell pools.

Current patient and healthcare worker attitudes to eHealth and the personally controlled electronic health record in major hospitals.

BACKGROUND: The current health system in Australia is comprised of both electronic- and paper-based medical records. The Federal Government has approved funding for the development of an individual health identifier and a universally adopted online health repository. AIMS: To determine attitudes and beliefs of patients and healthcare workers regarding the use of stored medical information and the personally controlled electronic health record (PCEHR) in selected major hospitals in Victoria. METHODS: Qualitative survey of patients and healthcare workers (n = 600 each group) conducted during 2014 across five major hospitals in Melbourne to measure the awareness, attitudes and barriers to electronic health and the PCEHR. RESULTS: Of the patients, 93.3% support the concept of a shared electronic healthcare record, 33.7% were aware of the PCEHR and only 11% had registered. The majority of healthcare workers believed that the presence of a shared health record would result in an increased appropriateness of care and patient safety by reducing adverse drug events and improving the timeliness of care provided. However, only 46% of healthcare workers were aware of the PCEHR. CONCLUSIONS: This study provides a baseline evaluation of perceptions surrounding eHealth and PCHER in acute health services in five metropolitan centres. While there appears to be a readiness for adoption of these strategies for healthcare documentation, patients require motivation to register for the PCEHR, and healthcare workers require more information on the potential benefits to them to achieve more timely and efficient care.

Human leucocyte antigen-defined microchimerism early post-transplant does not predict for stable lung allograft function.

Microchimerism is the presence of foreign cells in an individual below 1% of total cells, which can occur in the setting of solid organ transplantation. This study quantitated donor-derived cellular subsets longitudinally in human leucocyte antigen (HLA)-mismatched lung transplant recipients (LTR) during the first post-operative year and evaluated the pattern of peripheral microchimerism with clinical outcomes. Peripheral blood mononuclear cells (PBMC) isolated from non-HLA-B44 LTR who received HLA-B44 allografts were sorted flow cytometrically into three cellular subsets. Real-time quantitative polymerase chain reaction (q-PCR) demonstrated that donor-derived HLA-B44 microchimerism is a common phenomenon, observed in 61% of patients. The level of donor-derived cells varied across time and between LTR with frequencies of 38% in the B cells/monocytes subset, 56% in the T/NK cells subset and 11% in the dendritic cells (DC) subset. Observations highlighted that microchimerism was not necessarily associated with favourable clinical outcomes in the first year post-lung transplantation.

Preemptive treatment with voriconazole in lung transplant recipients.

BACKGROUND: Invasive fungal infection (IFI) is associated with high mortality in lung transplant (LTx) recipients. Data for voriconazole use in preemptive treatment remain scant. METHOD: A single-center, retrospective cohort study was conducted to investigate the efficacy and safety of voriconazole preemptive treatment for post-LTx colonization. RESULTS: We reviewed 62 adult LTx patients, who received their first course of voriconazole prophylaxis (i.e., as preemptive treatment) between July 2003 and June 2010. Outcomes were determined at 6 and 12 months after commencing therapy. Aspergillus fumigatus (75.8%) was the most common colonizing isolate. Median duration of voriconazole prophylaxis was 85 days. At 6 months, 1 LTx patient (1.6%) had IFI, 47 (75.8%) cleared their colonizing isolate, 3 (4.8%) had persistent colonization, 7 (11.3%) had recurrent colonization, 1 (1.6%) had new colonization, 2 (3.2%) had aspergilloma, and 1 (1.6%) was clinically unstable with no culture results. Sixteen (25.8%) had died by 12 months. Ten (16.1%) had likely drug-related hepatotoxicity. LTx patients with diabetes mellitus within 30 days before commencing prophylaxis were at higher risk of recurrent Aspergillus colonization at 6 months (P = 0.030). Chronic rejection within 30 days before prophylaxis was associated with 12-month mortality (P = 0.007). CONCLUSIONS: Voriconazole preemptive treatment resulted in low incidence of IFI and IFI-related mortality.

Cytomegalovirus replication within the lung allograft is associated with bronchiolitis obliterans syndrome.

Early studies reported cytomegalovirus (CMV) pneumonitis as a risk factor for development of bronchiolitis obliterans syndrome (BOS) following lung transplantation. While improvements in antiviral prophylaxis have resulted in a decreased incidence of CMV pneumonitis, molecular diagnostic techniques allow diagnosis of subclinical CMV replication in the allograft. We hypothesized that this subclinical CMV replication was associated with development of BOS. We retrospectively evaluated 192 lung transplant recipients (LTR) from a single center between 2001 and 2009. Quantitative (PCR) analysis of CMV viral load and histological evidence of CMV pneumonitis and acute cellular rejection was determined on 1749 bronchoalveolar lavage (BAL) specimens and 1536 transbronchial biopsies. CMV was detected in the BAL of 41% of LTR and was significantly associated with the development of BOS (HR 1.8 [1.1-2.8], p = 0.02). This association persisted when CMV was considered more accurately as a time-dependent variable (HR 2.1 [1.3-3.3], p = 0.003) and after adjustment for significant covariates in a multivariate model. CMV replication in the lung allograft is common following lung transplantation and is associated with increased risk of BOS. As antiviral prophylaxis adequately suppresses CMV longer prophylactic strategies may improve long-term outcome in lung transplantation.

Antifungal prophylaxis in lung transplantation--a world-wide survey.

While variations in antifungal prophylaxis have been previously reported in lung transplant (LTx) recipients, recent clinical practice is unknown. Our aim was to determine current antifungal prophylactic practice in LTx centers world-wide. One nominated LTx clinician from each active center was invited by e-mail to participate in a web-based survey between September 2009 and January 2010. Fifty-seven percent (58/102) responded. The majority of responses were from medical directors of LTx centers (72.4%), and from the United States (44.8%). Within the first 6 months post-LTx, most centers (58.6%) employed universal prophylaxis, with 97.1% targeting Aspergillus species. Voriconazole alone, and in combination with inhaled amphotericin B (AmB), were the preferred first-line agents. Intolerance to side effects of voriconazole (69.2%) was the main reason for switching to alternatives. Beyond 6 months post-LTx, most (51.8%) did not employ antifungal prophylaxis. Fifteen centers (26.0%) conducted routine antifungal therapeutic drug monitoring during prophylactic period. There are differences in strategies employed between U.S. and European centers. Most respondents indicated a need for antifungal prophylactic guidelines. In comparison to earlier findings, there was a major shift toward prophylaxis with voriconazole and an increased use of echinocandins, posaconazole and inhaled lipid formulation AmB.

Adverse events arising from a palliative care survey.

Development of evidence-based practice requires investigation of the attitudes and needs of patients, families and healthcare professionals, particularly for sensitive subject areas. Cystic fibrosis (CF) is a recessively inherited life-limiting disorder resulting in early death. Patients with this condition generally expect that lung transplantation will be an available treatment option; however, this is uncertain. A dual approach to care that involves both preparing patients for transplant assessment, while simultaneously exploring acceptable palliative care options is needed. A survey amongst patients with CF, their families and health carers was conducted to understand their attitudes and needs in relation to end-of-life care. The survey encompassed five separate domains, with a total of 60 questions requiring approximately 20 min to complete. Of the 200 surveys sent to patients, 82 (41%) completed responses were received. The Institutional Ethics Committee received six complaints from families of seven patients (3.5% of those surveyed). This article explores the nature of the adverse responses to the survey. The majority of complaints were received from family members rather than from patients. Complaints described dissatisfaction with the topic, little warning about the study and felt it to be inappropriate for their family member's level of health. Survey instruments used to determine attitudes and needs in relation to end-of-life patient care are likely to elicit adverse responses that should be reported in a similar way to other investigational studies. Also arising from adverse responses and the complaint process, is the impact of criticism on study researchers.

Lung transplantation in pulmonary fibrosis: challenging early outcomes counterbalanced by surprisingly good outcomes beyond 15 years.

Interstitial lung disease (ILD) has been reported to have a poor outcome following lung transplantation due to difficulties getting ill recipients to transplantation and challenging early postoperative outcomes. To assess long-term outcomes for this cohort, we performed a retrospective 18-year chart review of all ILD lung transplant recipients. ILD single (SLT) and bilateral sequential lung transplantations (BSLT) were compared with all other lung transplant patients and International Society for Heart and Lung Transplantation (ISHLT) Registry data over the same time period. Of 585 lung transplantations, 90 (15%) were ILD (53 SLT, 37 BSLT); 67 (74%) were idiopathic pulmonary fibrosis (IPF), 9 (10%) were sarcoidosis, 9 (10%) were lymphangioleiomyomatosis, and 5 (6%) had other indications. Mean age was 52 years (range, 34-69 years). Actuarial survival at 1, 5, 10, 15, and 18 years compared favorably to all other lung transplantations performed (77% vs 83%, 51% vs 50%, 42% vs 26%, 28% vs 17%, and 28% vs 8%, respectively). IPF actuarial survival at 1, 5, and 10 years appeared superior to ISHLT Registry data (76% vs 72%, 50% vs 44%, and 34% vs 20%, respectively). There was equivocal survival between SLT and BSLT at 1, 5, and 10 years (78% vs 68%, 49% vs 50%, and 29% vs 50%, respectively). Our ILD figures compared favorably to lung transplantation for other diseases and international standards, while survival from SLT was as successful as BSLT both in the short and the longer term. Consideration should be given to utilizing SLT to maximize the allocation of donor lungs and to decrease waiting list mortality associated with IPF.

Linking CMV serostatus to episodes of CMV reactivation following lung transplantation by measuring CMV-specific CD8+ T-cell immunity.

CMV-specific immunity was assessed in a longitudinal cohort of 39 lung transplant recipients (LTR) who were followed prospectively from the time of transplant using a novel assay. At the time of surveillance bronchoscopy, CMV-specific CD8(+) T-cell responses were assessed in the peripheral blood, using the QuantiFERON-CMV assay, which measures IFN-gamma-secreting T cells following stimulation with CMV peptides. In total, 297 samples were collected from 39 LTR (CMV D+/R-, n = 8; D+/R+, n = 18; D-/R+, n = 6; D-/R-, n = 7). CMV-specific T-cell immunity was not detected in any of the CMV D-/R- LTR. In CMV seropositive LTR levels of CMV immunity were lowest early posttransplant and increased thereafter. While levels of CMV-specific immunity varied between LTR, measurements at any one time point did not predict episodes of CMV reactivation. In CMV mismatched (D+/R-) LTR, primary CMV immunity was not observed during the period of antiviral prophylaxis, but typically developed during episodes of CMV reactivation. Measuring CMV-specific CD8(+) T-cell function with the QuantiFERON-CMV assay provides insights into the interrelationship between CMV immunity and CMV reactivation in individual LTR. A better understanding of these dynamics may allow the opportunity to individualize antiviral prophylaxis in the future.

Randomised placebo controlled trial of non-invasive ventilation for hypercapnia in cystic fibrosis.

BACKGROUND: The clinical benefits of domiciliary non-invasive positive pressure ventilation (NIV) have not been established in cystic fibrosis (CF). We studied the effects of nocturnal NIV on quality of life (QoL), functional and physiological outcomes in CF subjects with awake hypercapnia (arterial carbon dioxide pressure PaCO2>45 mm Hg). METHODS: In a randomised, placebo controlled, crossover study, eight subjects with CF, mean (SD) age 37 (8) years, body mass index 21.1 (2.6) kg/m2, forced expiratory volume in 1 s 35 (8)% predicted and PaCO2 52 (4) mm Hg received 6 weeks of nocturnal (1) air (placebo), (2) oxygen and (3) NIV. The primary outcome measures were CF specific QoL, daytime sleepiness and exertional dyspnoea. Secondary outcome measures were awake and asleep gas exchange, sleep architecture, lung function and peak exercise capacity. RESULTS: Compared with air, NIV improved the chest symptom score in the CF QoL Questionnaire (mean difference 10; 95% CI 5 to 16; p = 0.002) and the transitional dyspnoea index score (mean difference 3.1; 95% CI 1.2-5.0; p = 0.01). It reduced maximum nocturnal pressure of transcutaneous CO2 (PtcCO2 mean difference -17 mm Hg; 95% CI -7 to -28 mm Hg; p = 0.005) and increased exercise performance on the Modified Shuttle Test (mean difference 83 m; 95% CI 21 to 144 m; p = 0.02). NIV did not improve sleep architecture, lung function or awake PaCO2. CONCLUSION: 6 weeks of nocturnal NIV improves chest symptoms, exertional dyspnoea, nocturnal hypoventilation and peak exercise capacity in adult patients with stable CF with awake hypercapnia. Further studies are required to determine whether or not NIV can improve survival.

CD8+ T-cell maturation following lung transplantation: the differential impact of CMV and acute rejection.

Studies on persistent viral infections demonstrate that CD8(+) T-cells differentiate along distinct pathways following chronic antigen exposure; however the effect of stimulation with non-viral chronic antigens is poorly described. We assessed the contributions that the presence of an allograft or cytomegalovirus (CMV) has on the post-thymic differentiation of CD8(+) T-cells in both the blood and lung allograft in patients undergoing lung transplantation. CD28 expression on blood CD8(+) T-cells was reduced in CMV seropositive patients, and was further reduced following acute episodes of CMV reactivation. These viral-associated changes in phenotype were not seen in CD8(+) T-cells isolated from the lung allograft where a different pattern of CD28 expression was observed. Following transplantation there was a progressive reduction in CD28 expression on BAL CD8(+) T-cells. In contrast to what was observed in peripheral blood, reduced CD28 expression on BAL CD8(+) T-cells was associated with a reduced gamma-IFN production. Furthermore, a high proportion of CD28-CD8(+) T-cells in the BAL was associated with fewer episodes of acute allograft rejection. An expanded CD28-CD8(+) T-cell subset, with reduced function, within the lung allograft may have important prognostic implications in lung transplant recipients.

CMV-specific CD8 T-cell dynamics in the blood and the lung allograft reflect viral reactivation following lung transplantation.

Despite the potentially high burden of cytomegalovirus (CMV)-related disease following lung transplantation, the role of the cytotoxic T-lymphocyte (CTL) response to CMV in this patient group is ill-defined. We assessed the CMV-specific T-cell response in the blood and lung allograft of immunosuppressed lung transplant recipients receiving antiviral prophylaxis and following their withdrawal. While the proportion of CMV-specific CTL varied between patients, in the absence of CMV reactivation the level of CMV-specific CD8+ T cells in the blood remained stable over time. In the majority of patients CMV-specific cells could be detected in the lung allograft, often in the absence of viral DNA. Additionally, following primary CMV lung infection, CMV-specific CD8+ T cells were detected no earlier than 100 days post-transplantation but still prior to the detection of viral DNA in the lung allograft. Together these findings suggest that very low levels of CMV replication are sufficient to both prime and recruit CMV-specific CD8+ T cells to the MHC-mismatched lung allograft. The direct detection of CMV-specific T cells with an effector phenotype in the lung allograft suggests a protective antiviral function. This study provides a framework upon which the association between CMV and chronic allograft rejection can be further studied.

The dynamics and associations of airway neutrophilia post lung transplantation.

UNLABELLED: Bronchoalveolar lavage (BAL) neutrophilia has been repeatedly observed in lung transplant recipients with established bronchiolitis obliterans syndrome (BOS). Little is known of the fluctuations in BAL and airway neutrophilic inflammation post-transplant. This prospective longitudinal study aimed to evaluate the dynamic changes of lung allograft neutrophils with time, immunosuppression, infection and BOS. A total of 28, initially healthy, BOS 0, lung transplant recipients underwent 134 bronchoscopic assessments, including BAL and endobronchial biopsies (EBB) (with immunohistochemistry) over 3-year follow up. Subsequently, 21 developed BOS 0p and 16 ultimately BOS. Compared to controls, there was early and persistent BAL neutrophilia (p < 0.05), contrasting with an initially normal EBB that shows a progressive increased airway wall neutrophil infiltrate. BAL neutrophilia (but not airway wall neutrophilia) was most striking when there was concomitant bronchopulmonary infection, particularly in the patients with BOS. Univariate and multivariate analyses suggested that BAL neutrophilia was linked to markers of infection while EBB neutrophilia was linked with coexistent inflammation with macrophages and lymphocytes. IN CONCLUSION: (i) BAL neutrophilia is predominantly associated with infection; (ii) Airway wall neutrophilia (as monitored by EBB) increases with time post-transplant and is not associated with infection; (iii) By itself, BOS is not the major contributor to BAL and EBB neutrophilia.

Reduced bone density in cystic fibrosis: DeltaF508 mutation is an independent risk factor.

The aim of this cross-sectional study was to determine the prevalence and identify determinants of reduced bone mineral density (BMD) in adults with cystic fibrosis (CF). Adults (88) with CF (mean+/-SD age 29.9+/-7.7 yrs; forced expiratory volume in one second (FEV1) 58.2+/-21.5% of the predicted value) were studied. BMD at the lumbar spine (LS) and femoral neck (FN) and body composition were measured using dual-energy X-ray absorptiometry. Blood and urine were analysed for hormones, bone turnover markers, and the cytokines tumour necrosis factor-alpha, and interleukin-6 and -1beta. FEV1 (% pred); CF genotype; malnutrition; history of growth, development or weight gain delays; and corticosteroid use were analysed. BMD Z-scores were -0.58+/-1.30 (mean+/-SD) at the LS and -0.24+/-1.19 at the FN. Z-scores of <-2.0 were found in 17% of subjects. Subjects who were homozygous or heterozygous for the DeltaF508 mutation exhibited significantly lower Z-scores than those with no DeltaF508 allele. Multiple linear regression showed that the DeltaF508 genotype and male sex were independently associated with lower BMD at both sites. Other factors also independently associated with lower BMD included malnutrition, lower 25-hydroxyvitamin D level, lower fat-free mass and lower FEV1 (% pred). In conclusion, reduced bone mineral density in cystic fibrosis is associated with a number of factors, including DeltaF508 genotype, male sex, greater lung disease severity and malnutrition.

Cytomegalovirus viral load monitoring after allogeneic bone marrow transplantation in patients receiving antiviral prophylaxis.

Cytomegalovirus viral load measurement is a powerful new tool for monitoring of CMV disease; however, the optimal strategy for use is unknown. Weekly plasma CMV viral loads and CMV-related outcomes were monitored in 46 consecutive allogeneic bone marrow transplantation (BMT) recipients receiving standardised antiviral prophylaxis. A total of 412 CMV viral loads were quantitated in the first 100 days post transplantation with 77 positive samples (19%) in 20 patients (43%). No patient with all negative CMV viral load results developed CMV disease. Two of three patients with highly positive CMV viral loads (first positive < or =30 days post transplant, maximum viral load > or =5000 copies/ml, and > or =50% of samples positive) developed CMV disease. A total of 17 patients with positive CMV viral loads, who did not meet the criteria for highly positive, did not develop CMV disease. CMV viral load detection was higher in recipients who were CMV sero-positive. In conclusion, CMV disease did not occur in the setting of a persistently negative CMV viral load. A positive CMV viral load result occurred commonly after allogeneic BMT, even in patients receiving antiviral prophylaxis.

Provision of laboratory services for heart and lung transplantation in Australia.

BACKGROUND: Laboratory services for the support of heart and lung transplantation in Australia have adapted to the special needs of the clinicians looking after the heart and lung transplantation patients. METHODS: Pre-transplantation standardized tests encompassing a wide variety of different parameters are carried out both to establish the suitability of patients for a transplant and to maximize the chance of success following this procedure. Potential solid organ recipients routinely have blood samples sent to a number of centers Australia-wide so that human leukocyte antigen (HLA) presensitization can be checked for at the time a donor becomes available in any state in Australia. Although prospective HLA matching is not performed for thoracic organ transplant recipients, pre-existing antibodies to donor HLA antigens are a contra-indication to transplantation. Following transplantation, the predominant roles of the laboratory are in the monitoring of immunosuppressive drug levels, in the detection of allograft rejection, and in the detection of bacterial infection or viral reactivation. While a number of markers have been proposed in the detection of rejection, we currently rely on interpretation of the histological analysis of biopsies. The treatment with immune suppressive agents, in particular cyclosporin A, has made organ transplantation from non-HLA identical donors possible. As cyclosporin A and other immune suppressive drugs have significant side effects, their concentrations need to be carefully followed to guarantee sufficient immune suppression while avoiding renal failure and other complications including excessive immunosuppression and infectious disease risk. Recently, the role of viral reactivation with the human cytomegalovirus (HCMV) has attained more prominence. HCMV is a potential pathogen in up to 90% of thoracic organ transplant recipients and in the pre-gancyclovir era, it was a major cause of morbidity and mortality in at-risk lung transplant recipients. New PCR-based assays that measure the viral load levels of HCMV allow earlier intervention and more appropriate treatment strategies to prevent the HCMV disease syndromes and optimize the HCMV prophylaxis strategy. CONCLUSIONS: Diagnostic pathology testing to support heart and lung transplantation is a combination of routine testing and specialized testing. Depending on the time-critical nature of the tests, this testing has to be done on site or in more centralized testing facilities. Further developments in the laboratory support of heart and lung transplantation will hopefully continue to improve both the short- and long-term outcomes of thoracic organ transplant recipients.

Comparison of a multiplex reverse transcription-PCR-enzyme hybridization assay with conventional viral culture and immunofluorescence techniques for the detection of seven viral respiratory pathogens.

A multiplex reverse transcription-PCR-enzyme hybridization assay (RT-PCR-EHA; Hexaplex; Prodesse Inc., Waukesha, Wis.) was used for the simultaneous detection of human parainfluenza virus types 1, 2, and 3, influenza virus types A and B, and respiratory syncytial virus types A and B. One hundred forty-three respiratory specimens from 126 patients were analyzed by RT-PCR-EHA, and the results were compared to those obtained by conventional viral culture and immunofluorescence (IF) methods. RT-PCR-EHA proved to be positive for 17 of 143 (11.9%) specimens, whereas 8 of 143 (5.6%) samples were positive by viral culture and/or IF. Eight samples were positive by both RT-PCR-EHA and conventional methods, while nine samples were RT-PCR-EHA positive and viral culture and IF negative. Eight of the nine samples with discordant results were then independently tested by a different multiplex RT-PCR assay for influenza virus types A and B, and all eight proved to be positive. In comparison to viral culture and IF methods, RT-PCR-EHA gave a sensitivity and a specificity of 100 and 93%, respectively. Since RT-PCR-EHA was able to detect more positive samples, which would otherwise have been missed by routine methods, we suggest that this multiplex RT-PCR-EHA provides a highly sensitive and specific means of diagnostic detection of major respiratory viruses.

Increased human cytomegalovirus (HCMV) DNA load in peripheral blood leukocytes after lung transplantation correlates with HCMV pneumonitis.

BACKGROUND: Human cytomegalovirus (HCMV) reactivation and disease remain relatively common in lung transplant recipients (LTR) despite the use of ganciclovir prophylaxis protocols for all HCMV at-risk patients. The specific aims of this study were to (1) describe the HCMV DNA viral load in the peripheral blood leukocytes (PBL) of a cohort of LTR during the first 6 months after lung transplantation; (2) prospectively determine whether HCMV DNA viral load predicts episodes of HCMV pneumonitis in LTR; and (3) study the effect of ganciclovir on HCMV viral load. METHODS: Competitive polymerase chain reaction using an internal standard and fluorometric detection were used to quantitate HCMV DNA in the PBL of a cohort of 26 LTR monthly for the first 6 months after transplantation (145 samples). All patients were treated with standard triple immunosuppression, and ganciclovir prophylaxis was given to all at-risk LTR (donor or recipient HCMV seropositive) for at least 8 weeks after transplantation. RESULTS: Thirteen episodes of histopathologically proven HCMV pneumonitis in nine subjects occurred during follow-up with a wide intra- and intersubject variation in the HCMV DNA PBL levels. HCMV detection had a sensitivity of 92% and specificity of 76% for HCMV pneumonitis (negative likelihood ratio, 9.5), whereas greater than 10-fold increases in HCMV DNA load had a specificity of 93% and sensitivity of 67% (positive likelihood ratio, 11). HCMV DNA detection had an adjusted odds ratio for HCMV pneumonitis of 107 (95% confidence interval, 14-821; P<0.005). In those with detectable HCMV DNA in PBL (n=44), HCMV DNA levels were 4.4 (95% confidence interval, 1.2-16.8) times higher in those with HCMV pneumonitis than in those without HCMV pneumonitis. Although ganciclovir treatment was very effective in treating HCMV pneumonitis and suppressing HCMV DNA levels, thrice weekly ganciclovir prophylaxis only partially controlled HCMV DNA levels and did not eliminate HCMV pneumonitis risk as three patients developed HCMV pneumonitis while on this regimen. CONCLUSIONS: HCMV DNA detection, absolute levels, and relative change from baseline in the PBL of LTR correlate with HCMV pneumonitis episodes and may be a useful intermediate outcome measure of the efficacy of ganciclovir prophylaxis and treatment strategies.