Citations

Abstract Nocardiosis is an uncommon yet potentially devastating infection. Nocardia tends to affect individuals with chronic lung disease or immunocompromising conditions, 2 groups increasing in number. Incidence of nocardiosis is likely to increase as well, and it is vital to have an approach to this complex disease. Here, we aim to review the presentation, diagnosis, and management of Nocardia in the modern era. We will also highlight areas of uncertainty in our understanding of nocardiosis and propose a general approach to nocardiosis therapy, accounting for response and tolerance of Nocardia treatment.

AbstractBackgroundDevelopment of brain abscess following solid organ transplantation is associated with significant morbidity and mortality. We undertook a descriptive study to evaluate the etiology, clinical manifestations, diagnosis, management, and outcomes of brain abscess in solid organ transplant (SOT) recipients at three major transplant centers in the United States.MethodsThis is a retrospective study of adults with brain abscess following SOT between January 2000 and June 2021 at Mayo Clinic sites in Arizona, Minnesota, and Florida.ResultsA total of 39 patients were diagnosed with a brain abscess following SOT. The most common pathogens were Nocardia sp. (24 cases, 61.5% [Nocardia farcinica, 37.5%]), followed by fungi (12 cases, 30.7% [Aspergillus sp., 83.3%]). The majority were kidney transplant recipients (59%). Median time to brain abscess diagnosis was 1.3 years (range, 29 days–12 years) after SOT; 10 of 12 patients (83%) with fungal brain abscess were diagnosed within 1 year after SOT. Twelve patients underwent brain biopsy for diagnosis (25% Nocardia vs. 50% fungal), eight (20.5%) underwent surgical resection of the abscess, and 31 (79.5%) received antimicrobial therapy alone. Median time to brain abscess resolution was 166 days for Nocardia and 356 days for fungal pathogens. Eleven of 39 patients (28.2%) died as a result of their brain abscess, including four of 24 patients (16%) with Nocardia and six of 10 patients (60%) with Aspergillus brain abscess. All‐cause mortality was 43.6%.ConclusionBrain abscess remains an uncommon infectious complication following SOT. Nocardia and fungi accounted for 92% of pathogens in our cohort. Fungal brain abscess portends a poor prognosis. image

ABSTRACT Introduction Hepatitis B virus (HBV) vaccination is recommended for solid organ transplant (SOT) candidates. However, there is a lack of data on the HBV vaccine compliance, serologic response, and durability of HBV seroprotection in thoracic organ transplantation recipients. Methods We conducted a retrospective study of adult thoracic organ (heart and lung) transplant candidates who received HBV vaccination at Mayo Clinic sites in Minnesota, Arizona, and Florida between January 2018 and August 2023. Conventional recombinant hepatitis B vaccine (Recombivax HB) was used before 2020, and Heplisav‐B was preferred after 2020. HBV seroprotection was defined as hepatitis B surface antibody (HBsAb) ≥ 10 IU/L. Furthermore, we compared characteristics between recipients who maintained HBV seroprotection and those who lost HBV seroprotection (HBsAb < 10 IU/L) at 30 days posttransplantation (D30). Results Among 922 candidates who were eligible for HBV vaccination, 430 (47%) completed the HBV vaccine series. Patients receiving Heplisav‐B were more likely to complete the series than Recombivax HB (81% vs. 60%, p < 0.001) and Heplisav‐B had a higher seroprotection rate than Recombivax HB (75% vs. 64%, p = 0.023). Multivariate logistic regression analysis identified receiving Heplisav‐B as an independent predictor for HBV seroprotection (adjusted odds ratio [aOR] 1.723; 95% confidence interval [CI] 1.056–2.810; p = 0.029). A total of 145 thoracic organ transplant recipients achieved HBV seroprotection at the date of transplantation. Loss of HBV seroprotection occurred in 38 (26%) patients at D30. Multivariate logistic regression analysis identified two predictors for HBV seroprotection loss at D30: age ≥ 60 years (aOR, 2.503; 95% CI 1.026–6.107; p = 0.044), and pretransplant HBsAb level between 10 and 100 IU/L (aOR, 18.575; 95% CI 5.211–66.209; p < 0.001). Conclusions Although less than half of thoracic organ transplant candidates completed HBV vaccine series pretransplant, Heplisav‐B provided a higher vaccine completion rate and seroprotection than the 3‐dose Recombivax HB. Clinicians should also be aware of the increased loss of HBV seroprotection in thoracic organ transplant recipients with age ≥ 60 years and pretransplant HBsAb between 10 and 100 IU/L. Assessment of seroprotection after HBV vaccination should be prioritized during the pretransplant period.

Background. Identification and treatment of latent tuberculosis infection (LTBI) mitigate the risk of tuberculosis (TB) reactivation after transplantation. TB reactivation is higher in those with indeterminate QuantiFERON (QFT) than those with negative results. Management of indeterminate QFT results in the pretransplant period remains unclear. Methods. We conducted a retrospective study of solid organ transplant (SOT) recipients, 18 y and older, who were screened with QFT assay pretransplantation at Mayo Clinic between January 2010 and June 2023. We examined the frequency of indeterminate QFT results, results of repeat LTBI screening, treatment decisions, and rate of posttransplant TB infection. Results. Of 13 008 patients screened for LTBI before SOT, 736 (6%) patients had indeterminate QFT results. Among these, 247 (34%) underwent a second LTBI screening test, and 39 (5%) received LTBI treatment. Among 247 patients with a repeat LTBI screening test, 185 (75%), 48 (19%), and 14 (6%) were tested by QFT, T-SPOT.TB, or TST, respectively. The repeat QFT remained indeterminate in 160 (86%) patients, whereas all T-SPOT.TB results were negative. Posttransplant TB infection occurred in 2 (0.3%) patients; neither had a second TB screening test pretransplant nor received LTBI treatment. Conclusions. In SOT recipients with indeterminate QFT results at pretransplant evaluation, opting for T-SPOT.TB as a second test may be preferable over repeat QFT. TB infection after transplantation in patients with a pretransplant indeterminate QFT result was rare. Patient management and LTBI treatment in those with indeterminate QFT pretransplant should account for epidemiological risk factors, and shared decision-making is recommended.

ABSTRACTIntroductionHepatitis B virus reactivation (HBVr) can occur in solid organ transplant (SOT) recipients with previously inactive hepatitis B virus (HBV) infection. Previous studies have reported that HBVr is generally less than 10% in nonliver SOT recipients with past HBV infection.MethodsWe conducted a retrospective study from January 2018 to August 2023 at Mayo Clinic sites in Arizona, Florida, and Minnesota. We examined the antiviral prophylaxis strategy used and the characteristics of HBVr in hepatitis B core antibody‐positive (HBcAb +) nonliver SOT adult recipients. Past HBV infection was defined as HBcAb + / hepatitis B surface antigen (HBsAg) –. Chronic HBV infection was defined as HBcAb + / HBsAg +.ResultsA total of 180 nonliver SOT recipients were identified during the study period. Indefinite antiviral prophylaxis was utilized in 77 recipients, and none developed HBVr after transplantation. In 103 recipients without antiviral prophylaxis, the incidence of HBVr was 12% (12/97) and 33% (2/6) in those with past HBV infection and chronic HBV infection. The incidence of HBVr in patients with past HBV infection is 16% (8/50), 15% (3/20), and 5% (1/22) in kidney, heart, and lungs, respectively. HBVr was more frequent in those who received alemtuzumab. Among 14 recipients with HBVr, none had HBV‐associated liver failure or death.ConclusionsOur study observed a higher rate of HBVr (12%) in nonliver SOT recipients with past HBV infection compared to the previous studies. Further studies are needed to identify predictors of HBVr in nonliver SOT recipients and optimize antiviral prophylaxis guidance.

Background. Solid organ transplant (SOT) candidates should be screened and treated for latent tuberculosis infection (LTBI) to prevent tuberculosis (TB) reactivation after transplantation. We aimed to assess the steps from positive QuantiFERON (QFT) through LTBI treatment (cascade of care) in the SOT population. Methods. We conducted a retrospective study of SOT recipients older than 18 y with a positive QFT during pretransplant evaluation at the Mayo Clinic from January 2010 to June 2023. We analyzed each cascade step to determine associated drop-out factors for LTBI management. Results. Of 629 patients who had positive QFT results, 587 (93%) were evaluated by an infectious disease (ID) specialist, 478 (76%) were recommended to start LTBI treatment, 473 (75%) initiated LTBI treatment, and 457 (73%) completed LTBI treatment. LTBI treatment was not recommended in 109 patients evaluated by infectious disease, most of whom had previously received either LTBI (n = 72) or TB (n = 14) treatment. LTBI treatment was initiated before or after transplantation for 45% and 55% of patients, respectively. Isoniazid monotherapy was the most common regimen (92%), and adverse events were rare (7%). Seven patients developed active TB infection posttransplantation under various circumstances (3 without LTBI treatment, 1 during LTBI treatment, and 3 after completing LTBI treatment). Conclusions. Our findings demonstrate the variability of LTBI management in SOT recipients with positive QFT. When recommended, most patients completed LTBI treatment successfully. Nonetheless, active TB was noted regardless of whether patients received LTBI treatment. This study highlights the importance of optimizing LTBI management in this population.

Abstract Background Nocardia tends to cause infection in immunocompromised patients or those with chronic pulmonary disease. Nocardia is known to recur, prompting the practice of secondary prophylaxis in patients perceived at high risk. However, few data exist regarding the epidemiology of recurrent nocardiosis or the effectiveness of secondary prophylaxis. Methods We performed a multicenter, retrospective cohort study of adults diagnosed with nocardiosis from November 2011 to April 2022, including patients who completed primary treatment and had at least 30 days of posttreatment follow-up. Propensity score matching was used to analyze the effect of secondary prophylaxis on Nocardia recurrence. Results Fifteen of 303 (5.0%) patients developed recurrent nocardiosis after primary treatment. Most recurrences were diagnosed either within 60 days (N = 6/15, 40.0%) or between 2 to 3 years (N = 4/15, 26.7%). Patients with primary disseminated infection tended to recur within 1 year, whereas later recurrences were often nondisseminated pulmonary infection. Seventy-eight (25.7%) patients were prescribed secondary prophylaxis, mostly trimethoprim-sulfamethoxazole (N = 67/78). After propensity-matching, secondary prophylaxis was not associated with reduced risk of recurrence (hazard ratio, 0.96; 95% confidence interval, .24–3.83), including in multiple subgroups. Eight (53.3%) patients with recurrent nocardiosis required hospitalization and no patients died from recurrent infection. Conclusions Recurrent nocardiosis tends to occur either within months because of the same Nocardia species or after several years with a new species. Although we did not find evidence for the effectiveness of secondary prophylaxis, the confidence intervals were wide. However, outcomes of recurrent nocardiosis are generally favorable and may not justify long-term antibiotic prophylaxis for this indication alone.

Background. Surgical-site infections (SSIs) are common in liver transplant recipients. The optimal SSI antimicrobial prophylaxis agent and duration are not established. We aimed to explore risk factors for SSIs after transplant, with a particular interest in the impact of perioperative antibiotic regimen on the development of SSIs. Methods. Retrospective study of adults undergoing liver transplant across 3 transplant programs between January 1, 2020, and June 01, 2021. Results. Of 557 patients included in the study, 32 (5.7%) were infected or colonized with a multidrug-resistant organism (MDRO) within 1 y before liver transplant. Narrow-spectrum SSI prophylaxis with ceftriaxone or cefazolin alone was administered in 488 of 577 patients (87.6%); the remaining 69 patients (12.4%) received broad-spectrum prophylaxis with vancomycin and aztreonam (n = 40), piperacillin–tazobactam (n = 11), carbapenems (n = 8), ceftriaxone and another antibiotic (n = 7), and others. Patients with pretransplant MDRO were more likely to receive broad-spectrum coverage than those without pretransplant MDROs (28.1% versus 11.4%, P = 0.005). SSIs were identified in 40 patients (7.2%); 25 (62.5%) were organ–space infections, 3 (7.5%) were deep incisional infections, and 12 (30.0%) were superficial incisional infections. The median time from liver transplant to SSIs was 14 d (interquartile range, 10–20.2). MDROs were identified in 12 SSIs (30%). Multivariable analysis revealed no significant association between antimicrobial spectrum and risk of SSIs (P = 0.5), whereas surgical leak (P<0.001) and reoperation (P = 0.017) were independently associated with increased risk of SSIs. SSIs were not significantly associated with composite risk of death or liver allograft failure. Conclusions. The spectrum of antimicrobial prophylaxis did not impact the development of SSIs in liver transplant recipients.