Challenges in the Diagnosis and Management of Bacterial Lung Infections in Solid Organ Recipients: A Narrative Review

Abstract

Respiratory infections pose a significant threat to the success of solid organ transplantation, and the diagnosis and management of these infections are challenging. The current narrative review addressed some of these challenges, based on evidence from the literature published in the last 20 years. Specifically, we focused our attention on (i) the obstacles to an etiologic diagnosis of respiratory infections among solid organ transplant recipients, (ii) the management of bacterial respiratory infections in an era characterized by increased antimicrobial resistance, and (iii) the development of antimicrobial stewardship programs dedicated to solid organ transplant recipients.

The Airway Microbiota Signatures of Infection and Rejection in Lung Transplant Recipients

“…It is noteworthy that positive bacterial culture could be due to the presence of respiratory pathogens or colonized bacteria. In LTRs with a positive culture, those who did not fulfill the clinical criteria for respiratory infection (lack of symptoms/signs and radiologic changes) were classified by 2 clinicians as colonized patients ( 39 ). Thereafter the recipients with colonization were divided into groups according to the criteria of rejection and event-free.…”

Antibacterial activity of a new monocarbonyl analog of curcumin MAC 4 is associated with divisome disruption

“…We selected the compounds MACs 4, 6 and 8, which demonstrated a broad spectrum and potent activity, in order to evaluate their toxicity on human cells. Since M. tuberculosis and A. baumannii were the most sensitive species to the selected compounds and cause pulmonary infection [56,57], we investigated the toxicity against human lung cells, including fibroblast (MCR-5) and epithelial (A549) cell lines. MACs 4, 6 and 8 toxic effects were expressed according to the concentration required in order to reduce cell viability at 50% (IC 50 ) (Table 2).…”

Divergent airway microbiomes in lung transplant recipients with or without pulmonary infection

“…However, this approach has several drawbacks. For example, cultures are limited to known and culturable species, and they are unable to differentiate between microbes causing disease versus microbes colonizing asymptomatic carriers [ 6 ]. This was illustrated in an earlier study, where we demonstrated that bacterial findings in BALF cultures were similar in patients with and without clinical signs of infection at the time of sampling [ 7 ].…”

“…This was illustrated in an earlier study, where we demonstrated that bacterial findings in BALF cultures were similar in patients with and without clinical signs of infection at the time of sampling [ 7 ]. The difficulty in interpreting culture findings emphasizes the great need for new tools, including microbiome analyses, to identify and understand the aetiology of respiratory infections in these patients [ 6 ].…”