Zachary A Yetmar

Dr. Zachary A Yetmar

orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 June 2021 in Open Forum Infectious Diseases
Verified
Journal Article
Open access
PDF file
ZYZachary A Yetmar
Zachary A Yetmar
EBElena Beam
Elena Beam
JOJohn C O’hOro
John C O’hOro
RGRavindra Ganesh
Ravindra Ganesh
DBDennis M Bierle
Dennis M Bierle
RRRaymund R. Razonable
Raymund R. Razonable
Bamlanivimab and casirivimab-imdevimab are authorized for emergency use treatment of mild to moderate coronavirus disease 2019 (COVID-19) in patients at high risk for developing severe disease or hospitalization. Their safety and efficacy have not been specifically evaluated in solid organ transplant recipients. We retrospectively reviewed solid organ transplant recipients who received monoclonal antibody infusion for COVID-19 at Mayo Clinic sites through January 23, 2021. Outcomes included emergency department visit, hospitalization, mortality, and allograft rejection. Seventy-three patients were treated, most commonly with bamlanivimab (75.3%). The median age was 59 years, 63% were male, and the median Charlson comorbidity index was 5. Transplant type included 41 kidney (56.2%), 13 liver (17.8%), 11 heart (15.1%), 4 kidney-pancreas (5.5%), 2 lung (2.7%), 1 heart-liver, and 1 pancreas. Eleven (15.1%) patients had an emergency department visit within 28 days of infusion, including 9 (12.3%) who were hospitalized for a median of 4 days. One patient required intensive care unit admission for a nonrespiratory complication. No patients required mechanical ventilation, died, or experienced rejection. Ten adverse events occurred, with 1 seeking medical evaluation. Hypertension was associated with hospital admission (P < .05), while other baseline characteristics were similar. The median time from symptom onset to antibody administration was 4 days in nonhospitalized patients compared with 6 days among hospitalized patients (P < .05). Monoclonal antibody treatment has favorable outcomes with minimal adverse effects in solid organ transplant recipients with mild to moderate COVID-19. Earlier administration of monoclonal antibody therapy appears to be more efficacious.

15 April 2025 in Clinical Infectious Diseases
Verified
Journal Article
Closed access
ZYZachary A Yetmar
Zachary A Yetmar
PMPaige K Marty
Paige K Marty
JCJosh Clement
Josh Clement
CMCyndee Miranda
Cyndee Miranda
Nancy WengenackNancy Wengenack
Nancy Wengenack
EBElena Beam
Elena Beam
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.

1 August 2023 in Open Forum Infectious Diseases
Verified
Journal Article
Open access
PDF file
ZYZachary A Yetmar
Zachary A Yetmar
RKRyan B Khodadadi
Ryan B Khodadadi
SCSupavit Chesdachai
Supavit Chesdachai
JMJack W McHugh
Jack W McHugh
DCDouglas W Challener
Douglas W Challener
EBElena Beam
Elena Beam
Nocardia primarily infects patients who are immunocompromised or those with chronic lung disease. Although disseminated infection is widely recognized as an important prognostic factor, studies have been mixed on its impact on outcomes of nocardiosis. We performed a retrospective cohort study of adults with culture-confirmed nocardiosis. Advanced infection was defined as disseminated infection, cavitary pulmonary infection, or pleural infection. The primary outcome was 1-year mortality, as analyzed by multivariable Cox regression. Of 511 patients with culture growth of Nocardia, 374 (73.2%) who had clinical infection were included. The most common infection sites were pulmonary (82.6%), skin (17.9%), and central nervous system (14.2%). In total, 117 (31.3%) patients had advanced infection, including 74 (19.8%) with disseminated infection, 50 (13.4%) with cavitary infection, and 18 (4.8%) with pleural infection. Fifty-nine (15.8%) patients died within 1 year. In multivariable models, disseminated infection was not associated with mortality (hazard ratio, 1.16; 95% CI, .62–2.16; P = .650) while advanced infection was (hazard ratio, 2.48; 95% CI, 1.37–4.49; P = .003). N. farcinica, higher Charlson Comorbidity Index, and culture-confirmed pleural infection were also associated with mortality. Immunocompromised status and combination therapy were not associated with mortality. Advanced infection, rather than dissemination alone, predicted worse 1-year mortality after nocardiosis. N. farcinica was associated with mortality, even after adjusting for extent of infection. While patients who were immunocompromised had high rates of disseminated and advanced infection, immunocompromised status did not predict mortality after adjustment. Future studies should account for high-risk characteristics and specific infection sites rather than dissemination alone.

25 July 2022 in Transplant Infectious Disease
Verified
Journal Article
Closed access
ZYZachary A Yetmar
Zachary A Yetmar
EBElena Beam
Elena Beam
JOJohn C. O'HOro
John C. O'HOro
MSMaria Teresa Seville
Maria Teresa Seville
LBLisa Brumble
Lisa Brumble
RRRaymund R. Razonable
Raymund R. Razonable

28 October 2022 in Transplantation
Verified
Journal Article
Closed access
ZYZachary A Yetmar
Zachary A Yetmar
DCDouglas W. William Challener
Douglas W. William Challener
MSMaria Teresa Seville
Maria Teresa Seville
WBWendelyn Bosch
Wendelyn Bosch
EBElena Beam
Elena Beam
Background.: Nocardia is an environmental pathogen with a predilection for causing opportunistic infections in immunocompromised patients, including solid organ transplant (SOT) recipients. Although risk factors have been identified for developing nocardiosis in this population, little is known regarding clinical factors resulting in poor outcomes. We evaluated a cohort of SOT recipients with nocardiosis for associations with 12-month mortality. Methods.: We performed a multicenter retrospective cohort study of adult SOT recipients diagnosed with culture-confirmed nocardiosis from 2000 to 2020. Patients were followed for 12 months after diagnosis, unless abbreviated by mortality. Multivariable Cox regression was performed to analyze associations with 12-month mortality. A subgroup analysis of patients with disseminated nocardiosis was performed to analyze treatment variables. Results.: A total of 125 SOT recipients met inclusion criteria; 12-month mortality was 16.8%. Liver transplantation (hazard ratio [HR] 3.52; 95% confidence interval [CI] 1.27-9.76) and time from symptom onset to presentation (HR 0.92/d; 95% CI 0.86-0.99) were independently associated with 12-month mortality, whereas disseminated infection was not (HR 1.23; 95% CI 0.49-3.13). No treatment-specific factors were significantly associated with mortality in 33 patients with disseminated nocardiosis, although survivors had a higher rate of linezolid use. Conclusions.: This study identified 2 independent associations with 12-month mortality, representing demographics and infection severity. Disseminated infection was not independently associated with poor outcomes, and specific sites of infection may be more important than dissemination itself. No treatment-specific factors were associated with mortality, though this analysis was likely underpowered. Further study of treatment strategies based on specific Nocardia syndromes is warranted.

29 October 2020 in Open Forum Infectious Diseases
Verified
Journal Article
Open access
PDF file
ECEdison J Cano
Edison J Cano
ZYZachary A Yetmar
Zachary A Yetmar
RRRaymund R Razonable
Raymund R Razonable
Cryptococcus spp is a major cause of opportunistic infections in immunocompromised patients, primarily due to Cryptococcus neoformans and Cryptococcus gattii. There are occasional reports of other Cryptococcus species causing invasive human disease. However, their epidemiology and clinical significance are not fully defined. We sought to describe cases with cultures positive for Cryptococcus species other than C neoformans and C gattii. A retrospective descriptive analysis of clinical and laboratory data of patients with cultures growing Cryptococcus species other than C neoformans and C gattii from November 2011 to February 2019 was performed. Three Mayo Clinic sites in Arizona, Florida, and Minnesota were included. From 176 cases with a culture growing Cryptococcus spp, 54 patients (30%) had a culture for Cryptococcus other than C neoformans and C gattii in the study time frame. The most common species were Cryptococcus magnus, Cryptococcus laurentii, and Cryptococcus ater. The organisms were isolated and identified in culture of bronchoalveolar lavage (11), skin (11), urine (7), oral (4), sinus (3), intraoperative soft tissue (3), sputum (2), synovial fluid (2), cerebrospinal fluid (2), and intravenous catheter (2), among others (7). Only 8 (15%) cases were considered to be potentially pathogenic, with 1 case of invasive disease. Antifungal treatment was fluconazole, itraconazole, and griseofulvin, for a mean systemic antifungal duration of 42 days. This large series of patients with Cryptococcus spp other than C neoformans and C gattii suggests that these species rarely cause clinically significant infection in humans. Only 1 case of invasive disease was found.