Specific human leucocyte antigen-DQ risk epitope mismatches are associated with chronic lung allograft dysfunction after lung transplantation.

A high-risk epitope mismatch (REM) (found in DQA1∗05 + DQB1∗02/DQB1∗03:01) is associated with de novo donor specific antibodies after lung transplantation (LTx). Chronic lung allograft dysfunction (CLAD) remains a barrier to LTx survival. This study aimed to measure the association between DQ REM and the risk of CLAD and death after LTx. A retrospective analysis of LTx recipients at a single center was conducted between January 2014 and April 2019. Molecular typing at human leucocyte antigen-DQA/DQB identified DQ REM. Multivariable competing risk and Cox regression models were used to measure the association between DQ REM, time-to-CLAD, and time-to-death. DQ REM was detected in 96/268 (35.8%), and DQ REM de novo donor specific antibodies were detected in 34/96 (35.4%). CLAD occurred in 78 (29.1%), and 98 (36.6%) recipients died during follow-up. When analyzed as a baseline predictor, DQ REM status was associated with CLAD (subdistribution hazard ratio (SHR), 2.19; 95% confidence interval [CI], 1.40-3.43; P = .001). After adjustment for time-dependent variables, DQ REM dn-DSA (SHR, 2.43; 95% CI, 1.10-5.38; P = .029) and A-grade rejection score (SHR, 1.22; 95% CI, 1.11-1.35; P = <.001), DQ REM status was not independently associated with CLAD. DQ REM was not associated with death (hazard ratio, 1.18; 95% CI, 0.72-1.93; P = .51). Classification of DQ REM may identify patients at risk of poor outcomes and should be incorporated into clinical decision-making.

Identification of miR-93 as a suitable miR for normalizing miRNA in plasma of tuberculosis patients.

Tuberculosis (TB) remains a major public health issue. New tests to aid diagnoses and monitor the response to therapy are urgently required. There is growing interest in the use of microRNA (miRNA) profiles as diagnostic, prognostic or predictive markers in a range of clinical and infectious diseases, including Mycobacterium tuberculosis infection, however, challenges exist to accurately normalise miRNA levels in cohorts. This study examined the appropriateness of 12 miRs and RNU6B to normalise circulating plasma miRNA levels in individuals with active TB from 2 different geographical and ethnic regions. Twelve miRs (let-7, miR-16, miR-22, miR-26, miR-93, miR-103, miR-191, miR-192, miR-221, miR-423, miR-425 and miR-451) and RNU6B were selected based on their reported production by lung cells, expression in blood and previous use as a reference miRNA. Expression levels were analysed in the plasma of newly diagnosed TB patients from Australia and China compared with individuals with latent TB infection and healthy volunteers. Analysis with both geNorm and NormFinder software identified miR-93 as the most suitable reference miR in both cohorts, either when analysed separately or collectively. Interestingly, there were large variations in the expression levels of some miRs, in particular miR-192 and let-7, between the two cohorts, independent of disease status. These data identify miR-93 is a suitable reference miR for normalizing miRNA levels in TB patients, and highlight how environmental, and possibly ethnic, factors influence miRNA expression levels, demonstrating the necessity of assessing the suitability of reference miRs within the study population.

Systematic Reporting of Eosinophils in Transbronchial Biopsies After Lung Transplantation Defines a Distinct Inflammatory Response.

BACKGROUND: Descriptions of eosinophils in transbronchial biopsy (TBBx) pathology reports after lung transplantation (LTx) are associated with poor long-term outcomes. The absence of routine reporting and standardization precludes accurate assessment of this histologic predictor. A systematic reporting scheme for the presence of TBBx eosinophils after LTx was implemented. This report aims to assess this scheme by describing the presence, pattern, and gradation of TBBx eosinophils and clinical associations. METHODS: A prospective cross-sectional study of all TBBx reports was performed including all patients presenting for a surveillance or diagnostic TBBx between January 2020 and June 2023. Each TBBx was systematically reported in a blinded manner. Mixed-effects logistic regression was performed to measure the association between concurrent clinical and histologic features, and the presence of TBBx eosinophils. RESULTS: A total of 410 TBBx reports from 201 patients were systematically reported. In 43.8% recipients, any TBBx eosinophils were detected and in 17.1% recipients, higher-grade eosinophils (≥3 per high power field) were present. Adjusted analysis showed that retransplantation, A- and B-grade cellular rejection, positive bronchoalveolar lavage (BAL) bacterial microbiology, and elevated blood eosinophil count were independently associated with the presence of any TBBx eosinophils. Diagnostic "for-cause" procedures were independently associated with higher quantities of TBBx eosinophils. CONCLUSIONS: Systematic reporting demonstrates that TBBx eosinophils are a distinct inflammatory response associated with rejection, infection, and peripheral eosinophilia. Although these findings require multicenter external validation, standardized reporting for TBBx eosinophils may assist in identifying recipients at risk of poor outcomes and provides a platform for mechanistic research into their role after lung transplantation.

Rapid cytological analysis of endobronchial ultrasound-guided aspirates in sarcoidosis.

Rapid on-site evaluation (ROSE) of endobronchial ultrasound-guided transbronchial needle aspirates (EBUS-TBNA) has not been compared to final detailed cytological analysis in patients with suspected sarcoidosis. To assess the diagnostic accuracy of EBUS-TBNA with ROSE in patients with suspected sarcoidosis, a prospective two-centre study performed EBUS-TBNA with ROSE of cellular material followed by transbronchial lung biopsy (TBLB) and endobronchial biopsy (EBB). The diagnostic accuracy of EBUS-TBNA with ROSE was compared to the final cytological assessment and to TBLB and EBB. Analysis confirmed 49 out of 60 cases of sarcoidosis. ROSE sensitivity was 87.8% (specificity 91%, positive predictive value 97.7%). ROSE slide interpretation in combination with the final fixed slide and cell block preparations had a sensitivity of 91.8% (specificity 100%, positive predictive value 100%). 67% of patients were confirmed as having sarcoidosis on TBLB and 29% on EBB. Interobserver agreement between cytotechnologists and pathologists was very good (κ=0.91, 95% CI 0.80-1.0 and κ=0.91, 95% CI 0.79-1.0, respectively). EBUS-TBNA with ROSE has high diagnostic accuracy and interobserver agreement and informs the bronchoscopist in theatre whether additional diagnostic procedures need to be undertaken. EBUS-TBNA with ROSE should therefore be considered as the first-line investigation of sarcoidosis.

Oral ribavirin for respiratory syncytial virus infection after lung transplantation: Efficacy and cost-efficiency.

BACKGROUND: Respiratory syncytial virus (RSV) causes serious respiratory tract infections in lung transplant (LTx) recipients, is associated with development of bronchiolitis obliterans syndrome, and has no proven effective therapy. We evaluated the efficacy, safety, and cost-effectiveness of oral ribavirin for the treatment of RSV infection after LTx. METHODS: Between December 2011 and May 2014, 52 LTx recipients developed 56 episodes of symptomatic RSV infection, which was diagnosed by positive RSV polymerase chain reaction on nasopharyngeal swabs. An intravenous (IV) loading dose of ribavirin (33 mg/kg) was given in 52 of 56 episodes; an equivalent oral loading dose was given in 2 episodes. Oral ribavirin (20 mg/kg/day) was given by day 2 in 53 of 56 episodes. Median duration of therapy was 8 days (range 6-31 days). RESULTS: Mean forced expiratory volume in 1 sec decreased from 2.38 ± 0.78 liters to 2.07 ± 0.85 liters (p < 0.001) at presentation, recovered to 2.26 ± 0.82 liters at cessation of ribavirin, and was maintained at 2.31 ± 0.81 liters within 3 months. New-onset bronchiolitis obliterans syndrome developed in 1 of 38 patients (2.6%) at 3 months. Anemia worsened in 23 episodes, and de novo anemia developed in 5 episodes. Mean hemoglobin decreased from 118 ± 16 g/liter to 113 ± 21 g/liter (p = 0.015). There were 4 late deaths. Compared with IV therapy, mean drug cost saving was US $6,035 per episode, and mean inpatient bed days was reduced by 6.7 days (p < 0.001). CONCLUSIONS: To our knowledge, we report the largest series of LTx recipients treated with oral ribavirin for RSV. Oral ribavirin appears to be an effective, well-tolerated alternative to IV or inhaled ribavirin; provides considerable cost savings and reduces length of hospital stay. Potential long-term benefits in preventing development of chronic lung allograft dysfunction are yet to be determined.

Enhanced clinical utility of de novo cyclosporine C2 monitoring after lung transplantation.

BACKGROUND: The 2-hour post-cyclosporine (CyA) dose concentration (C2) is favored as the best single-point correlate of CyA area-under-the-concentration curve. CyA nephrotoxicity is a prominent cause of renal dysfunction that affects 38% of lung transplant (LTx) recipients at 5 years. METHODS: We assessed the utility of de novo C2 monitoring after LTx by comparing 2 sequential groups of 18 bilateral LTx recipients followed with traditional de novo trough CyA (C0) monitoring and de novo C2 monitoring, respectively. Target C0 levels were 450 microg/liter and 250 microg/liter at 1 week and 3 months (3/12). Target C2 levels were 1,200 microg/liter and 800 microg/liter. Groups were matched for anthropometrics and diagnoses. Baseline serum creatinine (Cr) was lower in the C0 group than in the C2 group (65 +/- 17 vs 81 +/- 21 micromol/liter, p = 0.02). RESULTS: At 3 months, survival for both groups was 100%, but the C0 group had a greater increase in Cr from baseline (90 +/- 54% vs 33 +/- 23%, p < 0.001) despite similar CyA dosage (6.6 +/- 3.8 vs 6.5 +/- 2.9 mg/kg/day, p = 0.94). There was no difference in forced expiratory volume in 1 second (% predicted) (71 +/- 16 vs 69 +/- 14, p = 0.68), mean acute vascular rejection score per patient (2.61 +/- 2.12 vs 1.44 +/- 1.72, p = 0.079), mean bronchial rejection score per patient (3.72 +/- 1.81 vs 2.83 +/- 1.58, p = 0.126) or rate of infection (1.85 vs 1.79 events per 100 patient-days). CONCLUSIONS: De novo C2 monitoring, which reduces both the risk of CyA toxicity and the risk of sub-therapeutic dosing, is a safe and effective technique for short-term preservation of renal function after LTx.

Cyclosporine C2 monitoring improves renal dysfunction after lung transplantation.

BACKGROUND: Cyclosporine (CyA) toxicity is a potential cause of renal dysfunction, which occurs in 38% of lung transplant (LTx) recipients within 5 years. Reducing CyA to "sub-therapeutic" trough (C0) levels increases the risk of rejection. The 2-hour post-dose concentration (C2) is favored as the best single-point surrogate measure of CyA area under the curve (AUC), which reflects drug exposure. In this investigation we assess the effect of conversion to CyA C2 monitoring on renal dysfunction after LTx. METHODS: Fifteen patients (M:F = 12:3), aged 47 +/- 14 years (range 28 to 62), 3.5 +/- 2.7 (0.2 to 9.0) years post-LTx, with C0 in the therapeutic range (maintenance 100 to 200 microg/liters) (Behring/EMIT immunoassay) and abnormal renal function, were converted from C0 monitoring to C2 monitoring with dose reductions targeting C2 levels of 300 to 600 microg/liter over a 12-month period. RESULTS: CyA dose was reduced from 6.4 +/- 7.3 (1.2 to 27.9) to 3.1 +/- 2.7 (0.8 to 9.0) mg/kg/day (p = 0.04), with a reduction in C2 levels from 799 +/- 341 (299 to 1,466) to 390 +/- 148 (195 to 675) microg/liter (p < 0.001). Improvements in serum creatinine (0.20 +/- 0.07 [0.12 to 0.35] vs 0.16 +/- 0.04 [0.11 to 0.22] mmol/liter [p = 0.005]) were maintained during the study follow-up period of 1 year. Only 1 patient developed acute rejection and group mean forced expiratory volume in 1 second (FEV(1)) remained stable (2.4 +/- 1.0 [1.1 to 4.0] vs 2.4 +/- 1.2 [1.1 to 4.6] liters). CONCLUSIONS: C2 monitoring is a practical method of improving renal dysfunction that allows safe dose reductions of CyA when formal AUC monitoring is not feasible. Extended use of this strategy is associated with long-term benefits.

Indirect fluorescent antibody testing of nasopharyngeal swabs for influenza diagnosis in lung transplant recipients.

BACKGROUND: Rapid and reliable diagnosis of respiratory viral infections (RVI) in lung transplant recipients is essential to direct therapy of acute graft dysfunction and identify epidemic trends. Traditional techniques of serology and viral culture are limited by the lack of antibody response and delay in diagnosis. METHODS: We examined the clinical utility of indirect fluorescent antibody (IFA) testing in adult lung transplant patients with suspected RVI, compared with serology and culture. Nasopharyngeal and throat swabs (NT) were obtained to sample epithelial cells, followed by application of monoclonal antibody to respiratory syncytial virus, adenovirus, parainfluenza 1-3 and influenza A and B. The Bartels Respiratory Viral Detection kit was used with IFA results available within 24 hours. RESULTS: Nine of 18 patients tested positive for RVI with influenza A (n = 8) and influenza B (n = 1) detected. The sensitivity of IFA (67%) was higher than that of cell culture (45%). With intensive supportive therapy, infection was self-limiting in bronchiolitis obliterans syndrome (BOS) Grade 0-2 patients. However, patients with BOS Grade 3 manifested an acute exacerbation of airflow obstruction, which proved to be irreversible. CONCLUSIONS: Lung transplant patients with "flu-like" symptoms should proceed to IFA testing of NT swab specimens for early diagnosis. Samples collected within 7 days of symptom onset have high sensitivity as compared with serology and viral culture techniques.

Risk factors and management of bleeding associated with transbronchial lung biopsy in lung transplant recipients.

The aim of this study was to assess specific risk factors associated with bleeding during transbronchial biopsy (TBBx) in lung transplant recipients. Risk factors analyzed included gender, type of transplant, acute rejection, bronchiolitis obliterans syndrome (BOS) status, infections, number of biopsies obtained per procedures, serum creatinine level and post-operative day since transplantation. The bronchoscope was not wedged to obtain TBBx and associated bleeding was managed using the "back-and-forth" technique. The severity of bleeding is shown to be independent of any specific risk factor and the back-and-forth technique described herein can be safely employed in lung transplant recipients to manage bleeding associated with TBBx performed without wedging of the bronchoscope.

Sexual health issues after lung transplantation: importance of cervical screening.

To determine the incidence and outcomes of human papillomavirus infection and cervical abnormalities after lung transplantation, we performed a retrospective cross-sectional study of all 166 female recipients who underwent transplantation between February 1989 and June 2001 at our institution. The incidence of low-grade epithelial abnormality of the cervix, cervical intra-epithelial neoplasia (CIN) 1, and the earliest pre-cancerous changes of the cervical epithelial cells, CIN 3, in the post-transplant cohort was 42.2 and 30, respectively, per 1000 women screened compared with 8.3 and 6.2 per 1000 women screened (20-69 years old) in a large reference population. We conclude that the incidence of cervical abnormalities in lung transplant recipients is significantly greater than in the general population. The importance of regular surveillance in immunosuppressed patients to decrease the burden of disease from this potentially fatal but treatable condition is emphasized.

Prospective analysis of 1,235 transbronchial lung biopsies in lung transplant recipients.

OBJECTIVE: Fiber-optic bronchoscopy with multiple transbronchial lung biopsies (TBB) is the gold standard of evaluation of the pulmonary allograft post-lung transplantation (LT). However, controversy exists regarding the need for surveillance procedures and number of biopsy specimens required for satisfactory yield. The potential morbidity in obtaining multiple TBB specimens remains poorly described. We report the largest series of TBB in LT recipients to date, highlighting the occurrence of acute rejection and infection for surveillance and diagnostic procedures. The safety of TBB is analyzed and a biopsy schedule proposed. METHODS: Prospective analysis of 1,235 TBB in 230 LT recipients performed at St Vincent's Hospital from January 1995 to June 2000. RESULTS: Eight hundred thirty-six (67.7%) TBB were performed as surveillance and 399 (32.3%) for a clinical indication. No significant acute rejection (AR) or infection was disclosed in 53.3% of procedures. The Lung Rejection Study Group requirement of at least five pieces of evaluable lung parenchyma was achieved in 98.2% of procedures. The average number of evaluable fragments per procedure was 6.4, whereas only 3 TBB (0.24%) contained no lung parenchyma and 44 (3.6%) no bronchial wall. Histologic features of AR, lymphocytic bronchiolitis or infection were found in 18.9% of surveillance and 86.4% of clinical TBBs. The yield of surveillance procedures between 4 and 12 months was just 1.1% for cytomegalovirus and 6.1% for AR. The overall complication rate was 6.35% with no deaths recorded. CONCLUSION: Taking 10 to 12 TBB specimens has a high diagnostic yield and rarely fails to provide adequate tissue. The role of surveillance procedures post-lung transplantation remains controversial.

Successful lung transplantation for adolescents at a hospital for adults.

OBJECTIVE: To describe the results of lung transplantation (LTx) in adolescents at a hospital for adults. DESIGN AND SETTING: Prospective cohort study set in an LTx unit at an adult tertiary referral hospital from 1991 to 2006. PATIENTS: 37 consecutive adolescent lung transplant recipients including 13 males and 24 females (mean age, 16.7+/-2.0 [SD] years; range 12-19 years) who received heart-lung (six patients) or bilateral LTx (31 patients) for cystic fibrosis (29), congenital heart disease (four), acute respiratory failure (two), or another disorder (two). Two patients were transplanted after invasive ventilation, five after non-invasive ventilation and two after extracorporeal membrane oxygenation. MAIN OUTCOME MEASURES: Overall survival compared with an adult cohort; survival free of bronchiolitis obliterans syndrome (BOS); overall and BOS-free survival in those transplanted before and after January 2000. RESULTS: Mean waiting time was 273 days (range, 5-964 days; median, 163 days), mean donor age was 28 years (range, 9-53 years). Median inpatient stay was 11 days (range, 7-94 days). Mean follow-up was 1540+/-1357 days (range, 35-5163 days). The 5-year survival rate for the 16 patients transplanted before January 2000 was 38%, versus 74% for the 21 transplanted since January 2000 (P=0.05; Mantel-Cox). Overall, 18 of 35 evaluable patients developed BOS. Only BOS was associated with an increased mortality risk (P<0.01). CONCLUSION: LTx may be performed successfully in adolescents at a hospital for adults.

Intravenous ribavirin is a safe and cost-effective treatment for respiratory syncytial virus infection after lung transplantation.

BACKGROUND: Community-acquired viral infections, such as respiratory syncytial virus (RSV), represent a risk factor for bronchiolitis obliterans syndrome (BOS), the major limiting factor for long-term survival after lung transplantation (LTx). RSV often presents with acute bronchiolitis and may be fatal in 10% to 20% of patients. Standard therapies for RSV include nebulized ribavirin with or without steroids, but are costly and inconvenient. We investigated the utility of intravenous (IV) ribavirin with steroids for the treatment of RSV infection after LTx. METHODS: RSV was identified in nasopharyngeal and throat swabs (NPS) using indirect fluorescent antibody (IFA) testing in 18 symptomatic patients, which was confirmed by viral culture in 14. Data were collected for the period between April 2002 and October 2004. The study included 10 men and 8 women, mean age 42 +/- 15 (range 18 to 63) years. Transplant procedures were 5 single LTx and 13 bilateral LTx. RSV diagnosis was made on Day 1,374 +/- 1,270 (range 61 to 4,598, median 935) post-operatively. Underlying diagnoses included cystic fibrosis (n = 9), emphysema (n = 7) and pulmonary fibrosis (n = 2). All 18 patients received intravenous (IV) ribavirin (33 mg/kg on Day 1 and 20 mg/kg/day thereafter in 3 divided doses) with oral prednisolone (1 mg/kg) until repeat NPS were negative for RSV on IFA. Median therapy was 8 days (6 to 15). RESULTS: The mortality rate was 0%. Mean FEV1 fell from 2.1 +/- 1.0 liter (0.7 to 3.7 liters) to 1.8 +/- 0.9 liter (0.5 to 3.6 liters) (p < 0.001), but recovered to 2.1 +/- 0.9 (0.7 to 3.7 liters) within 3 months and was maintained at follow-up of 521 +/- 328 days (141 to 1,023 days, median 302). Only 1 patient developed bronchiolitis obliterans syndrome (BOS). Complications included mild hemolytic anemia (blood hemoglobin fell from 122 +/- 22 [84 to 154] g/liter to 107 +/- 18 [75 to 138] g/liter, p = 0.02). Cost savings per 8-day course were $US15,913 when compared with nebulized therapy at 6 g/day (p < 0.001). CONCLUSIONS: This is the largest reported series of treated RSV cases after LTx and the first to show that therapy with IV ribavirin and oral corticosteroids is well tolerated and effective. Cost utility vs nebulized therapy has been established. Early diagnosis and management are essential to prevent airway epithelial injury and subsequent BOS.

Association of minimal rejection in lung transplant recipients with obliterative bronchiolitis.

The clinical significance of minimal acute rejection (grade A1) in lung transplant recipients is unknown. We prospectively analyzed 1,159 transbronchial lung biopsies in 184 patients. Two hundred seventy-nine biopsies in 128 participants confirmed A1 histology at a mean postoperative day of 229 +/- 340. Sixty four of 255 surveillance A1 lesions progressed to high-grade acute rejection by 3 months of follow-up, whereas 40 developed new lymphocytic bronchiolitis. Twenty-four A1 biopsies were symptomatic, with only two cases progressing to high-grade rejection after steroid therapy. Seventy-eight of 184 patients experienced multiple (> or = 2) A1 biopsies in the first 12 months after transplant. Bronchiolitis obliterans syndrome developed in 68% of patients with multiple A1 lesions at a mean of 599 +/- 435 days, compared with 43% of patients with one or less A1 lesions at a mean of 819 +/- 526 (p = 0.022). Eighteen patients experienced multiple A1 biopsies after transplant in the absence of high-grade rejection episodes yet also developed earlier obliterative bronchiolitis (456 +/- 245 days, p = 0.020). We conclude that for A1 transbronchial lung biopsies, the conventional treatment of observation only is now challenged even in patients who are asymptomatic. Patients who experience multiple A1 lesions develop an earlier onset of obliterative bronchiolitis and may warrant alternative immunosuppressive strategies.