A 13-Year Nationwide Analysis of Nocardia and Actinomyces Infection Outcomes in Liver Transplant Recipients

Abstract

Liver transplant (LT) recipients have a profound susceptibility to infections. Although Nocardia and Actinomyces (NAs) are well-known bacteria that typically affect immunosuppressed patients, a scarcity of research exists on the effects of LT with NA infections. Our study aims to evaluate the outcomes associated with NA infections in patients with LT. Patients were selected from the National Inpatient Sample (NIS) from 2008 through 2020. International Classification of Disease revision 9 (ICD-9) and ICD revision 10 (ICD-10) codes. Patients admitted with a history of LT were subdivided into those who were and were not diagnosed with an NA infection. Records were weighted using the NIS algorithm. Primary outcomes were all-cause hospital mortality, acute kidney injury (AKI), acute myocardial infarction (AMI), shock, and a composite of these. Secondary outcomes were length of stay, total charges, cytomegalovirus (CMV), and transplant rejection. Demographics and comorbidities were compared between the groups with a weighted chi-square test. Outcomes were compared between the two groups, and adjusted odds ratios (ORs) and regression coefficients were calculated using weighted logistic or linear regression as appropriate. ORs were adjusted for age, gender, race, hospital characteristics, Charlson Comorbidity Index (CCI), median income based on zip code, weekend admission, and insurance. There were 469,141 patients with LT who were included in this study, 310 of them had NA infection (0.07%). Patients in each group were of similar age, race, and overall medical complexity (P > .05). Patients with NA infection were less likely to have a history of coronary artery disease (CAD; 4.84% vs 16.20%, P < .05), hypertension (14.53% vs 25.82%, P < .05), and obesity (1.61% vs 9.0%, P < .05) than the healthy controls. Patients with LT with NA infection were found to have higher odds of mortality (OR = 5.50, P < .001), AKI (OR = 1.9, P < .05), composite outcome (OR = 2.19, P < 0.01), and more likely to have CMV infection (OR = 6.38, P < .01). Patients with LT with NA infection stayed 13.11 days longer in the hospital (P < .01) with charges of $60,399 more (P < .01) than the healthy controls. Patients with LT who acquired an NA infection were at nearly six-fold higher odds of death and other negative outcomes. Based on previous research that has demonstrated organ transplant patients to be at high risk of infections, more vigilant care should be taken to protect patients with LT from such opportunistic infections.