Infections after lung transplantation

Abstract

The good clinical result of lung transplantation is constantly undermined by the high incidence of infection, which negatively impacts on function and survival. Moreover, infections may also have immunological interactions that play a role in the acute rejection and in the development of chronic lung allograft dysfunction. There is a temporal sequence in the types of infection that affects lung allograft: in the first postoperative month bacteria are the most frequent cause of infection; following this phase, cytomegalovirus and Pneumocystis carinii are common. Fungal infections are particularly feared due to their association with bronchial complication and high mortality. Scrupulous postoperative surveillance is mandatory for the successful management of lung transplantation patients with respect to early detection and treatment of infections. This paper is aimed to address clinicians in the management of the major infectious complications that affect the lung transplant population.

Bronchoalveolar lavage cytokines are of minor value to diagnose complications following lung transplantation

“…Sixth, infection was defined based on microbiological findings in BAL fluid only and did not take into account clinical symptoms, imaging studies, macroscopic appearance of BAL fluid and concomitant antibiotic, antiviral or antifungal medication. Detecting infection and differentiating infection from ACR based on clinical symptoms may be difficult in LTRs [33,55]. Thus, in patients on multiple immunosuppressive drugs the mere presence of pathogens in BAL fluid in the absence of clinical deterioration may fulfill criteria of infection and prompt anti-infective treatment.…”

“…Anti-infective prophylaxis is used as previously described [30,31]. All patients classified as cytomegalovirus (CMV) intermediate-risk or high-risk received prophylaxis with valganciclovir [32,33]. In case of CLAD, macrolides are given for immunomodulation [29].…”

Lung Transplantation and Precision Medicine

“…Finally, transplanted patients are, as previously mentioned, more prone to severe community-acquired or nosocomial infections with relatively innocuous infectious [52]. Time affects which type of infection a lung transplant patient can develop (Table 22.4) [50]. However, infections are more difficult to diagnose in lung transplant patients as classic symptoms such as fever, loss of appetite, fatigue, chills, night sweats and pain may be unremarkable or absent, whereas white blood cell count is commonly altered due to immunosuppressive therapy; also, loss of lung function may be observed in lung infection but is also a common trait in acute and chronic rejection.…”

“…Moreover, as a result of the mandatory lifelong immunosuppression and its resultant immune system impairment, lung transplant patients are more vulnerable to infectious agents, both bacterial, viral and fungal [50]. Infection should therefore always be excluded before a diagnosis of acute allograft rejection is made [51].…”

A prevalent and culturable microbiota links ecological balance to clinical stability of the human lung after transplantation

“…This offers unique opportunities for longitudinal studies on the lung microbiota composition and allows establishing links to the host's immune state and to clinical metadata. Due to different types of clinical complications such as infection (Nosotti et al, 2018), acute cellular or humoral rejection (Martinu et al, 2011) and Chronic Lung Allograft Dysfunction (CLAD) , the transplanted lung also offers the opportunity to study the respiratory microbiota (Borewicz et al, 2013;Charlson et al, 2012;Gregson et al, 2013;Willner et al, 2013) under a wide variety of ecological conditions. A better understanding of the dynamics of the lung ecosystem in this context can ultimately help limit the burden of morbidity and mortality associated with posttransplant complications and promote graft survival.…”