The Geographic Distribution of Dimorphic Mycoses in the United States for the Modern Era.

BACKGROUND: The dimorphic mycoses (DMs) of the United States-Histoplasma, Coccidioides, and Blastomyces-commonly known as endemic mycoses of North America (in addition to Paracoccidioides) are increasingly being diagnosed outside their historical areas of endemicity. Despite this trend, the maps outlining their geographic distributions have not been updated in more than half a century using a large, nationwide database containing individual-patient-level data. METHODS: This was a retrospective analysis of >45 million Medicare fee-for-service beneficiaries from 1 January 2007 through 31 December 2016. Diagnoses of histoplasmosis, coccidioidomycosis, and blastomycosis were defined by International Classification of Diseases, Ninth/10th Revision, codes. The primary outcome was the incidence of histoplasmosis, coccidioidomycosis, and blastomycosis for each US county. Clinically meaningful thresholds for incidence were defined as 100 cases/100 000 person-years for histoplasmosis and coccidioidomycosis and 50 cases/100 000 person-years for blastomycosis. RESULTS: There were 79 749 histoplasmosis, 37 726 coccidioidomycosis, and 6109 blastomycosis diagnoses in unique persons from 2007-2016 across 3143 US counties. Considering all US states plus Washington, DC, 94% (48/51) had ≥1 county above the clinically relevant threshold for histoplasmosis, 69% (35/51) for coccidioidomycosis, and 78% (40/51) for blastomycosis. CONCLUSIONS: Persons with histoplasmosis, coccidioidomycosis, and blastomycosis are diagnosed in significant numbers outside their historical geographic distributions established >50 years ago. Clinicians should consider DM diagnoses based on compatible clinical syndromes with less emphasis placed on patients' geographic exposure. Increased clinical suspicion leading to a subsequent increase in DM diagnostic testing would likely result in fewer missed diagnoses, fewer diagnostic delays, and improved patient outcomes.

Attributable Mortality of Candida Bloodstream Infections in the Modern Era: A Propensity Score Analysis.

BACKGROUND: This study quantifies the mortality attributable to Candida bloodstream infections (BSI) in the modern era of echinocandins. METHODS: We conducted a retrospective cohort study of adult patients admitted to Barnes Jewish Hospital, a 1368-bed tertiary care academic hospital, in Saint Louis, Missouri, from 1 February 2012 to 30 April 2019. We identified 626 adult patients with Candida BSI that were frequency-matched with 6269 control patients that had similar Candida BSI risk-factors. The 90-day all-cause mortality attributable to Candida BSI was calculated using three methods-propensity score matching, matching by inverse weighting of propensity score, and stratified analysis by quintile. RESULTS: The 90-day crude mortality was 42.4% (269 patients) for Candida BSI cases and 17.1% (1083 patients) for frequency-matched controls. Following propensity score-matching, the attributable risk difference for 90-day mortality was 28.4% with hazard ratio (HR) of 2.12 (95% confidence interval [CI], 1.98-2.25, P < .001). In the stratified analysis, the risk for mortality at 90 days was highest in patients in the lowest risk quintile to develop Candida BSI (hazard ratio [HR] 3.13 (95% CI, 2.33-4.19). Patients in this lowest risk quintile accounted for 81(61%) of the 130 untreated patients with Candida BSI. Sixty-nine percent of untreated patients (57/83) died versus 35% of (49/127) of treated patients (P < .001). CONCLUSIONS: Patients with Candida BSI continue to experience high mortality. Mortality attributable to Candida BSI was more pronounced in patients at lowest risk to develop Candida BSI. A higher proportion of these low-risk patients went untreated, experienced higher mortality, and should be the target of aggressive interventions to ensure timely, effective treatment.

Incidence and Mortality of COVID-19-Associated Invasive Fungal Infections Among Critically Ill Intubated Patients: A Multicenter Retrospective Cohort Analysis.

Background: An association between coronavirus disease 2019 (COVID-19)-associated invasive fungal infections (CAIFIs) and high mortality among intubated patients has been suggested in previous research. However, some of the current evidence was derived from small case series and multicenter studies conducted during different waves of the COVID-19 pandemic. We examined the incidence of CAIFIs and their associated mortality using a large, multicenter COVID-19 database built throughout the pandemic. Methods: We conducted a retrospective analysis of the National COVID Cohort Collaborative (N3C) database collected from 76 medical centers in the United States between January 2020 and August 2022. Patients were 18 years or older and intubated after severe acute respiratory syndrome coronavirus 2 infection. The primary outcomes were incidence and all-cause mortality at 90 days. To assess all-cause mortality, we fitted Cox proportional hazard models after adjusting for confounders via inverse probability weighting. Results: Out of the 4 916 229 patients with COVID-19 diagnosed during the study period, 68 383 (1.4%) met our cohort definition. The overall incidence of CAIFI was 2.80% (n = 1934/68 383). Aspergillus (48.2%; n = 933/1934) and Candida (41.0%; n = 793/1934) were the most common causative organisms. The incidence of CAIFIs associated with Aspergillus among patients who underwent BAL was 6.2% (n = 83/1328). Following inverse probability weighting, CAIFIs caused by Aspergillus (hazard ratio [HR], 2.0; 95% CI, 1.8-2.2) and Candida (HR, 1.7; 95% CI, 1.5-1.9) were associated with increased all-cause mortality. Systemic antifungals reduced mortality in 17% of patients with CAIFI with Aspergillus and 24% of patients with CAIFI with Candida. Conclusions: The incidence of CAIFI was modest but associated with higher 90-day all-cause mortality among intubated patients. Systemic antifungals modified mortality.

Shared Vision for Improving Outcomes for Serious Fungal Diseases: Report of a Patient, Caregiver, and Clinician Summit.

Background: Recently, increasing focus on patient input into research and healthcare improvements has fostered expanded patient-centered advocacy efforts. This first pan-fungal disease summit, part of the MYCology Advocacy, Research, & Education effort, brought together patients, caregivers, and mycology experts to better document patient experiences with invasive fungal disease (IFD) and establish priorities for mycology education, advocacy, and research. Methods: Patients who had suffered from IFD, their caregivers, clinicians, industry representatives, government officials, and patient advocacy professionals were invited. Patients and caregivers shared their stories and struggles with IFD. Breakout sessions separated mycology experts from patients and caregivers for further discussions to identify commonalities and perceived gaps and to formulate recommendations. The 2 groups then reconvened to develop consensus recommendations. Results: IFD patients and their caregivers shared experiences reflecting the typically lengthy prediagnosis, acute treatment, long-term treatment, and posttreatment recovery stages of IFD. They reported substantial physical, psychological, and financial burdens associated with the IFD experience, particularly related to delayed diagnoses. They reaffirmed a need for coordinated patient-centered education, peer support, and advocacy to document the burden of serious fungal infections. Mycology experts discussed strategies to address gaps in the mycology field, such as insufficient training, inadequate workforce support, and a need to partner more with patient groups. Conclusions: A summit involving patients with IFD, family caregivers, and mycology experts identified a substantial nonclinical burden of disease associated with IFD. Patients and mycology experts prioritized several goals for education, advocacy, and research to raise awareness of IFD and improve outcomes.

Creation and Internal Validation of a Clinical Predictive Model for Fluconazole Resistance in Patients With Candida Bloodstream Infection.

Background: Fluconazole is recommended as first-line therapy for candidemia when risk of fluconazole resistance (fluc-R) is low. Lack of methods to estimate resistance risk results in extended use of echinocandins and prolonged hospitalization. This study aimed to develop a clinical predictive model to identify patients at low risk for fluc-R where initial or early step-down fluconazole would be appropriate. Methods: Retrospective analysis of hospitalized adult patients with positive blood culture for Candida spp from 2013 to 2019. Multivariable logistic regression model was performed to identify factors associated with fluc-R. Stepwise regression was performed on bootstrapped samples to test individual variable stability and estimate confidence intervals (CIs). We used receiver operating characteristic curves to assess performance across the probability spectrum. Results: We identified 539 adults with candidemia and 72 Candida isolates (13.4%) were fluc-R. Increased risk of fluc-R was associated with older age, prior bacterial bloodstream infection (odds ratio [OR], 2.02 [95% CI, 1.13-3.63]), myelodysplastic syndrome (OR, 3.09 [95% CI, 1.13-8.44]), receipt of azole therapy (OR, 5.42 [95% CI, 2.90-10.1]) within 1 year of index blood culture, and history of bone marrow or stem cell transplant (OR, 2.81 [95% CI, 1.41-5.63]). The model had good discrimination (optimism-corrected c-statistic 0.771), and all of the selected variables were stable. The prediction model had a negative predictive value of 95.7% for the selected sensitivity cutoff of 90.3%. Conclusions: This model is a potential tool for identifying patients at low risk for fluc-R candidemia to receive first-line or early step-down fluconazole.

Management of Histoplasmosis by Infectious Disease Physicians.

Background: The Infectious Diseases Society of America (IDSA) guidelines for the management of histoplasmosis were last revised 15 years ago. Since those guidelines were compiled, new antifungal treatment options have been developed. Furthermore, the ongoing development of immunomodulatory therapies has increased the population at increased risk to develop histoplasmosis. Methods: An electronic survey about the management practices of histoplasmosis was distributed to the adult infectious disease (ID) physician members of the IDSA's Emerging Infections Network. Results: The survey response rate was 37% (551/1477). Only 46% (253/551) of respondents reported seeing patients with histoplasmosis. Regions considered endemic had 82% (158/193) of physicians report seeing patients with histoplasmosis compared to 27% (95/358) of physicians in regions not classically considered endemic (P < 0.001). Most ID physicians follow IDSA treatment guidelines recommending itraconazole for acute pulmonary (189/253 [75%]), mild-moderate disseminated (189/253 [75%]), and as step-down therapy for severe disseminated histoplasmosis with (232/253 [92%]) and without (145/253 [57%]) central nervous system involvement. There were no consensus recommendations observed for survey questions regarding immunocompromised patients. Conclusions: Though there are increased reports of histoplasmosis diagnoses outside regions classically considered endemic, a majority of ID physicians reported not seeing patients with histoplasmosis. Most respondents reported adherence to IDSA guidelines recommending itraconazole in each clinical situation. New histoplasmosis guidelines need to reflect the growing need for updated general guidance, particularly for immunocompromised populations.

Blastomycosis.

Blastomycosis is the fungal disease caused by thermally dimorphic fungi in the genus Blastomyces, with B dermatitidis complex causing most cases. It is considered hyperendemic in areas adjacent to the Great Lakes and along the St. Lawrence, Mississippi, and Ohio rivers, but definitive geographic distribution of blastomycoses remains obscure. Clinical presentation is variable. Disseminated blastomycosis with extrapulmonary manifestations is more common in immunosuppressed individuals. Culture positivity is required for definitive diagnosis, but compatible histology is often sufficient for presumptive diagnosis and initiation of treatment. Treatment should be provided to all symptomatic cases to prevent progression or recurrence.