Update on Nocardia infections in solid-organ transplantation

Abstract

Purpose of review Nocardia is a ubiquitous pathogen associated with life-threatening opportunistic infections. Organ transplant recipients are uniquely predisposed to Nocardia infections due to their iatrogenic cell-mediated immune deficit necessary to maintain allograft function. This review aims to address recent updates in the epidemiology, clinical presentation, diagnostics, treatment, and outcomes of Nocardia infections in solid-organ transplant recipients. Recent findings The incidence of Nocardia infection depends on multiple patient and environmental factors. Among transplant recipients, lung recipients are most commonly affected. Species identification and antimicrobial susceptibility testing are critical for optimizing therapy as substantial variation occurs among and within Nocardia spp. This has been increasingly accomplished through advances in molecular methods leading to improved accuracy and wider accessibility to testing. There are emerging data applying novel therapeutics and short course therapy that may offer alternative management approaches for transplant associated nocardiosis to minimize drug toxicity and intolerance. Summary Further prospective, multicenter studies are needed to better characterize the epidemiology of Nocardia in transplant recipients, as well as evaluate the impact of diagnostic advancements and new treatment strategies.

Clinical Characteristics and Treatment Outcome of Central Nervous System Nocardiosis: A Systematic Review of Reported Cases

“…The risk of nocardiosis is highest during the first year after solid organ transplant. Furthermore, the incidence of Nocardia infection was described as highest in heart and lung transplant recipients and lowest with liver and renal transplants [ 18 , 19 , 20 ]. Conversely, our review showed the highest cases of CNS infection in renal transplant recipients.…”

A taxonomically representative strain collection to explore xenobiotic and secondary metabolism in bacteria

“…Like T . paurometabola DSM 20162 T , those are all corynebacteria characterized by the presence of mycolic acids in their cell wall [ 42 ], and they are encountered in the clinic as opportunistic pathogens of concern [ 43 – 46 ]. Our computational analysis of T .…”

Nocardia Infections in the Immunocompromised Host: A Case Series and Literature Review

“…A matched case-control study comprising 5126 SOTRs demonstrated a 3.5% rate of infection among lung transplant recipients, with rates in heart, bowel, kidney, or liver recipients of 2.5%, 1.3%, 0.2%, and 0.1%, respectively [12]. Among SOTRs, lung recipients are the ones at major risk [4]. This can be explained by the increase in these procedures over time, the high levels of immunosuppression needed, and the unique risk of direct exposure of the allograft to the outside environment with an organism mostly acquired via inhalation [5].…”

“…Nocardia can seldom cause infections in immunocompetent subjects, but it is primarily considered an opportunistic pathogen, more commonly affecting patients with impaired immune systems such as solid-organ transplant recipients (SOTRs) and patients with haematologic malignancies [3][4][5][6][7][8][9].…”