Report from the 2018 consensus conference on immunomodulating agents in thoracic transplantation: Access, formulations, generics, therapeutic drug monitoring, and special populations

The Favorable impact of everolimus on Chronic lung allograft dysfunction in lung transplant recipients

Standard immunosuppressive therapy for lung transplant recipients combines a calcineurin inhibitor, an antimetabolite, and corticosteroids. In an observational, retrospective, monocentric study, we sought to compare the development of chronic lung allograft dysfunction (CLAD) between 37 patients who received this standard therapy (triple-therapy group) and 59 patients who received the mammalian target of rapamycin (mTOR) inhibitor everolimus in addition to the standard therapy (quadruple-therapy group). In the quadruple-therapy group, the time elapsed from transplantation to everolimus introduction (median [25th-75th percentile]) was 12 [7-25] months. In 46/59 cases, the indication for everolimus introduction was renal function sparing. Median follow-up durations were 36 [20-62] months and 84 [52-123] months in the triple-therapy and quadruple-therapy groups, respectively (p = 0.004). The incidence of CLAD was lower in patients receiving everolimus than in those who did not with an adjusted odds ratio of 0.303 [0.118-0.775]. In addition, the median time from transplantation to CLAD was longer in patients receiving quadruple therapy comprising everolimus than in those who did not (63 [30-92] vs. 29 [12-44] months; p = 0.025). This suggests that the addition of everolimus to a standard triple could result in a lower incidence of CLAD in lung transplant recipients.

Comparison of whole-blood sirolimus concentrations measured by EMIT-based Siemens Viva-ProE® System and LC-MS/MS in Chinese transplant patients

Sirolimus (SRL) is commonly used in transplant patients to prevent organ transplant rejection. The current guidelines recommend to perform SRL therapeutic drug monitoring regularly to improve treatment outcomes and avoid adverse effects. Consequently, a precise and accurate method for determining SRL is crucial in clinical practice. Currently, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and immunoassays have been widely adopted for determining SRL concentrations. However, previous studies have shown that immunoassays exhibit a positive bias compared to LC-MS/MS. As the new updated version of the EMIT-based Viva-E® System (SVPS), this study aims to compare SRL blood concentrations measured by the SVPS and LC-MS/MS. The residual whole-blood samples obtained from transplant patients were simultaneously analyzed using the SVPS and LC-MS/MS, respectively. The correlation between the two assays was analyzed using the linear regression analysis and Deming linear regression. The Pearson correlation coefficient and Intraclass correlation coefficient (ICC) analysis were executed. The Paired Wilcoxon test and Bland-Altman analysis were performed to assess the concordance between the two methods. The SVPS considerably increased SRL concentration value by 46.62 % as compared to the LC-MS/MS method. When SRL concentrations measured by the SVPS were above 4.0 ng/mL, there was no significant difference between the corrected SVPS concentrations after using the Deming linear regression equation, indicating their interchangeability. Given the significant disparities observed between EMIT and LC-MS/MS, it is crucial to indicate the methodology and instruments in both TDM reports and future clinical guidelines. Our study also provides the conversion formulas between the SVPS and LC-MS/MS, which can be applied as a reference for different clinical centers.

Preparing the Heart for a New Baby: Management of Pregnancy in Heart Transplant Recipients

Heart transplant (HT) recipients are more frequently reaching childbearing age given improvement in median survival and outcomes after HT. Although most pregnancies in HT recipients have favorable outcomes, poor fetal outcomes and maternal complications such as hypertensive disorders of pregnancy are more common in HT recipients than in the general population. In this review, we summarize the current evidence to guide the management of pregnancy in HT recipients. Preconception counseling, focused on risk stratification and optimal timing of conception, is the first important step to optimize pregnancy outcomes. During pregnancy and in the postpartum period, frequent monitoring of graft function and immunosuppressive levels is recommended. Calcineurin inhibitors and corticosteroids should be the mainstay of treatment for both prevention and treatment of graft rejection. Delivery planning should follow usual obstetric indications, preferably with vaginal delivery at term using regional anesthesia. A multidisciplinary care team should be involved in management through all stages of pregnancy to ensure success.

Gastrointestinal complications in pediatric lung transplant recipients: Incidence, risk factors, and effects on patient outcomes

BACKGROUND

Gastrointestinal (GI) complications in lung transplant recipients can occur any time during the post-operative period, leading to prolonged morbidity and mortality. Despite the negative association between GI complications and patient outcomes, little is known about their incidence and risk factors for their development in pediatric lung transplant recipients.

METHODS

We performed a retrospective chart review at one pediatric tertiary center to describe the frequency of GI complications in lung transplant recipients. We identified potential risk factors for the diagnosis of gastroparesis, gastroesophageal reflux disease (GERD) and aspiration in the post-transplant period. Lastly, we investigated the association of these complications with mortality and graft survival.

RESULTS

84.3% of lung transplant recipients experienced at least one GI complication in the post-transplant period. Gastroparesis (52.9%), GERD (41.2%), and oropharyngeal dysphagia/laryngeal penetration (33.3%) were the most common complications diagnosed. Post-operative opioid exposure was a risk factor for gastroparesis, with the odds increasing 3.0% each day a patient was prescribed opioids (p = .021). The risk of death or retransplant in individuals who experienced gastroparesis was 2.7 times higher than those not diagnosed with gastroparesis (p = .027).

CONCLUSION

Exposure to opioids in the post-operative period is a risk factor for gastroparesis and a prolonged hospitalization placed patients at risk for aspiration. Gastroparesis was associated with increased patient mortality and graft failure, while aspiration and GERD had no effect on long term outcomes. Future prospective studies investigating the relationship between opioid use and the development of a gastroparesis are necessary to improve patient outcomes.

ADONHERS (Aged DONor HEart Rescue by Stress Echo) National Protocol: Recipient's Survival after 10-Year Follow-Up

Background: The gold-standard treatment for end-stage heart failure is heart transplantation, but the lack of organ donors remains an important limitation in this field. An accurate selection of marginal hearts is fundamental to increase organ availability. Purpose: In our study we analyzed if recipients receiving marginal donor (MD) hearts, selected by dipyridamole stress echocardiography according to the ADOHERS national protocol, had different outcomes compared to recipients with acceptable donor (AD) hearts. Methods: Data were collected and retrospectively analyzed from patients who received an orthotopic heart transplant at our institution between 2006 and 2014. Dipyridamole stress echo was performed on identified marginal donors and selected hearts were eventually transplanted. Clinical, laboratory and instrumental features of the recipients were evaluated and patients with homogenous baseline characteristics were selected. Results: Eleven recipients transplanted with a selected marginal heart and eleven recipients transplanted with an acceptable heart were included. Mean donor age was 41 ± 23. The median follow-up was 113 months (IQR 86-146 months). Age, cardiovascular risk and morpho-functional characteristics of the left ventricle were comparable between the two populations (p > 0.05). Left atrial size was significantly higher in patients with marginal hearts (acceptable atrial volume: 23 ± 5 mL; marginal atrial volume: 38 ± 5 mL; p = 0.003). Acceptable donor recipients showed a higher impact of Cardiac Allograph Vasculopathy (p = 0.019). No rejection differences were found between the two groups. Four patients deceased, three were standard donor recipients and one was from the marginal donor group. Conclusions: Our study shows how cardiac transplant (Htx) from selected marginal donor hearts through a non-invasive bedside technique can alleviate the shortage of organs without a difference in survival compared to acceptable donor hearts.

[Follow-up strategies for lung transplant recipients in France]

BACKGROUND

Lung transplantation (LT) requires sustained care for a frequently polypathological condition. Follow-up is focused on three main issues: 1/stability of respiratory function; 2/comorbidity management; 3/preventive medicine. About 3000 LT patients in France are treated in 11 LT centers. Given the increased size of the LT recipient cohort, follow-up might be partially shared with peripheral centers.

METHODS

This paper presents the suggestions of a working group of the SPLF (French-speaking respiratory medicine society) on possible modalities of shared follow-up.

RESULTS

While the main LT center is tasked with centralizing follow-up, particularly the choice of optimal immunosuppression, an identified peripheral center (PC) may serve as an alternative to deal with acute events, comorbidities and routine assessment. Communication between the different centers should be free-flowing. Shared follow-up may be offered from the 3rd postoperative year to stable and consenting patients, whereas unstable and non-observant patients are poor candidates.

CONCLUSION

These guidelines may serve as a reference for any pneumologist wishing to effectively contribute to follow-up, even and especially subsequent to lung transplant.

Reproductive health after thoracic transplantation: An ISHLT expert consensus statement

Pregnancy after thoracic organ transplantation is feasible for select individuals but requires multidisciplinary subspecialty care. Key components for a successful pregnancy after lung or heart transplantation include preconception and contraceptive planning, thorough risk stratification, optimization of maternal comorbidities and fetal health through careful monitoring, and open communication with shared decision-making. The goal of this consensus statement is to summarize the current evidence and provide guidance surrounding preconception counseling, patient risk assessment, medical management, maternal and fetal outcomes, obstetric management, and pharmacologic considerations.

A comparison of outcomes after lung transplantation between European and North American centers

BACKGROUND

With advancements in basic science and clinical medicine, lung transplantation (LT) has evolved rapidly over the last three decades. However, it is unclear if significant regional variations exist in long-term outcomes after LT.

METHODS

To investigate potential differences, we performed a retrospective, comparative cohort analysis of adult patients undergoing deceased donor single or double LT in North America (NA) or Europe between January 2006 and December 2016. Data up to April 2019 were abstracted from the International Society for Heart and Lung Transplantation (ISHLT) Thoracic Organ Registry. We compared overall survival (OS) between North American and European LT centers in a propensity score matched analysis.

RESULTS

In 3,115 well-matched pairs, though 30-day survival was similar between groups (NA 96.2% vs Europe 95.4%, p = 0.116), 5-year survival was significantly higher in European patients (NA 60.1% vs Europe 70.3%, p < 0.001).

CONCLUSIONS

This survival difference persisted in a sensitivity analysis excluding Canadian patients. Prior observations suggest that these disparities are at least partly related to better access to care via universal healthcare models prevalent in Europe. Future studies are warranted to confirm our findings and explore other causal mechanisms. It is likely that potential solutions will require concerted efforts from healthcare providers and policymakers.

The Thiopurine Tale: An Unexpected Journey

Exactly 70 years ago [1951] mercaptopurine was discovered by Gertrude Elion as a novel treatment option for acute leukaemia. A total of three thiopurines (also thioguanine [1950] and azathioprine [1957]) were developed over time. These immunosuppressive drugs were also successfully introduced a few decades later to prevent rejection of transplanted organs and to treat several autoimmune diseases. For her discovery of thiopurines and other antimetabolite drugs, in 1988 Elion was rewarded, together with George Hitchings and James Black, with the Nobel Prize in Physiology or Medicine. Important steps have been made in recent years to unravel its metabolism, mode of action and pharmacogenetics. Today thiopurine [based] therapy remains an essential immunosuppressive approach in treating patients with inflammatory bowel disease.

Heart, kidney and left ventricular assist device: a complex trio

BACKGROUND

Heart failure (HF) is a complex syndrome affecting the whole body, kidneys included. The left ventricular assist device (LVAD) is a valid option for patients with very severe HF. Focusing on renal function, LVAD implantation could theoretically reverse the detrimental effects of HF syndrome on kidneys. However, implanting an LVAD is a high-risk surgical procedure, and LVAD patients have higher risk of bleeding, device thrombosis, strokes, renal impairment, multi-organ failure and infections. Furthermore, an LVAD has its own particular effects on the renal system.

METHODS

In this review, we provide a comprehensive overview of the complex interaction between LVAD and the kidneys from the pathophysiological and clinical perspectives. An analysis of the different effects of pulsatile-flow and continuous-flow LVAD is provided.

RESULTS

Despite their limitations, creatinine-based estimated glomerular filtration rate (eGFR) formulas help to stratify patients by their post-LVAD placement prognosis. Poor basal renal function, the onset of acute kidney injury or the need for renal replacement therapy after LVAD implantation negatively influences a patient's prognosis. LVAD can also prompt an improvement in renal function, however, with some counterintuitive effects on a patient's prognosis.

CONCLUSION

It is still hard to say whether different trends in eGFR depend on different renal conditions before LVAD placement, on a patient's better overall status or on a particular patient management strategy before and/or after the device's implantation. Steps should be taken to solve this question because finding the best candidates for LVAD implantation is of paramount importance to ensure the best outcomes.