1015. Hemophagocytic Lymphohistiocytosis: A Contemporary Single Center Case Series

Background

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of excessive inflammation due lack of normal downregulation of activated macrophages and lymphocytes. We describe clinical and laboratory features, underlying conditions, prognostic factors and outcomes of a contemporary cohort of adults with HLH.

Methods

We performed a retrospective case series of adults diagnosed and treated for HLH at the University of Kansas Medical Center from January 1, 2006 through September 30, 2017. Patients were identified by ICD9/10 search of our HERON database, followed by manual review of electronic medical records using the HLH-04 criteria for inclusion. Patients were followed until February 20, 2018. Descriptive statistics and Cox survival model for mortality were used for data analyses.

Results

Among 76 patients reviewed, 39 met the HLH-04 criteria and were included in the cohort. Median age was 46 years , 26 (66.7%) were male, 26 (66.7%) were white, 5 (12.8%) were Asian, and 5 (12.8%) were African American. Twenty-one patients (53.8%) had HLH associated with an infection and 11 patients (28.2%) had HLH associated with malignancy. Median follow up time was 180 days (range 1 – 4002 days). Twenty patients died with case fatality rate of 51.3%, and among those who died, median survival was 17 days (range 1 –180 days). On univariate analysis, variables associated with mortality were: male gender (hazard ratio (HR) 5.32, 95% confidence interval (CI) 1.51-18.78, p=0.004), age ≥ 65 years (HR 2.51, 95% CI 0.99-6.39, p-value 0.005) and bilirubin ≥ 5 mg/dL at diagnosis (HR 3.27, 95% CI 1.34-8.00, p=0.006). These remained significantly associated with mortality on multivariate analysis: male gender (HR 12.34, 95% CI 1.87-29.73, p=0.020) and age ≥ 65 years (HR 7.45, 95% CI 1.87-29.73, p=0.008) and bilirubin ≥ 5 mg/dL (HR 4.75, 95% CI 1.09-20.72, p=0.002).

Conclusion

In this retrospective case series of adults with HLH, mortality at a median follow up of 180 days remained high (53%) and is associated with older age age ( >65 years), male gender, and elevated bilirubin ≥ 5mg/dL at diagnosis. Better therapeutic options for this syndrome are needed.

Disclosures

All Authors: No reported disclosures

1153. Characterization of Invasive Mold Infections in Acute Leukemia and Hematopoietic Stem Cell Transplant Recipient Patients and Risk Factors for Mortality - a Single Center Experience

Background

Invasive mold infections (IMIs) remain a significant cause of morbidity and mortality in patients with acute leukemia (AL) and those undergoing hematopoietic stem cell transplantation (HSCT). We describe the epidemiology of IMIs, the incidence of IMI in patients with acute myelogenous Leukemia (AML) post HSCT, and risk factors for mortality.

Methods

Patients were identified using ICD9 and ICD10 codes using a University of Kansas internal database from 2009-2019, microbiology records, and an AML HSCT database and were followed through May 1^st, 2020. Patients’ electronic medical records were reviewed for inclusion. IMI was defined as proven or probable using the 2009 National Institute of Allergy and Infectious Diseases Mycoses Study Group (MSG) guidelines. Incidence was calculated as IMI cases/100-person-years. Risk factors for overall mortality were evaluated using a Cox regression model.

Results

We included 138 patients: 79 developed IMI after HSCT (8 autologous, 71 allogeneic) and 59 developed IMI after AL diagnosis. Seventeen of the AL patients underwent HSCT after IMI diagnosis (12 within 100 days of IMI). Proven IMI occurred in 45 (32.6%) and probable IMI occurred in 93 (67.4%) patients. The most common prophylactic agent prior to IMI diagnosis was fluconazole (31.2%), with 21.0% receiving none. Aspergillus was the most commonly identified mold with 91 (65.9%) cases. The average treatment duration was 101 (range 0 - 799) days. The incidence of IMI in patients with AML who underwent HSCT was 2.35 cases/100 person-years. All-cause mortality among patients with AL or HSCT who developed IMI was 23.1% at 6 weeks, 34.1% at 12 weeks, and 61.2% at 1 year. On univariate Cox model, Karnofsky performance status > 70 was associated with lower mortality (hazard ratio (HR) 0.317, 95% confidence interval (CI) [0.110, 0.914]) among HSCT recipients. ICU admission within 7 days prior to IMI diagnosis (HR 6.469, 95% CI [1.779, 23.530]) and each one point increase in BMI (HR 1.051, CI [1.001, 1.103]) were associated with increased mortality in the AL group.

Figure 1 - Invasive mold infections by pathogen in HSCT-recipients and acute leukemia patients from 2009-2019.

Figure 2 - Antifungal prophylactic agents prescribed for at least one week at time of IMI diagnosis

Table 1 - Univariate survival analysis calculated using a Cox proportional-hazards regression model among patients who developed IMI after HSCT and patients who developed IMI after acute leukemia diagnosis

Conclusion

IMIs are associated with significant mortality in HSCT recipients and AL patients; patients at higher risk for mortality include those with lower baseline Karnofsky scores, recent ICU admissions, and higher BMI at time of IMI diagnosis.

Disclosures

Wissam El Atrouni, MD, ViiV (Advisor or Review Panel member)

Scedosporium apiospermum fungemia successfully treated with voriconazole and terbinafine

Scedosporium apiospermum is ubiquitous in the environment and is considered an emerging infection. Immunocompromised hosts can have a wide spectrum of diseases ranging from cutaneous to disseminated disease that may involve pulmonary, central nervous system, or bone. Disseminated disease in immunocompetent hosts is uncommon. Treatment of deep-seated infections is challenging because of the limited susceptibility of the Scedosporium species to all current antifungal drugs. We report a case of Scedosporidium apiospermum fungemia with a presumed pulmonary involvement in an immunocompetent patient. The fungemia was successfully treated with oral voriconazole and terbinafine.

1711. Histoplasmosis-Associated Hemophagocytic Lymphohistiocytosis: A Case Series and Review of the Literature

Background

Methods

Results

Conclusion

Disclosures

Infections causing central airway obstruction: role of bronchoscopy in diagnosis and management

Central airway obstructive infections (CAOI) are challenging medical conditions that may represent an advanced and complicated process of ongoing infections. The epidemiology of CAOI is unknown as well as the pathophysiology and the mechanism of development. This is due to sparse data in the literature that consists mainly of case reports and retrospective case series. CAOI can be caused by fungal, bacterial, parasitic and viral infections. Most patients with CAOI can be diagnosed clinically and with chest imaging, which demonstrate obstruction of the central airways. However, bronchoscopy is commonly used to confirm and obtain a specific diagnosis to guide specific therapy. In recent years, interventional pulmonology (IP) is becoming widely available and offer a minimally invasive approach for the management of central airway diseases such as cancers, benign strictures, and other conditions. Various bronchoscopic modalities are used to treat central airway obstruction (CAO), such as mechanical debulking, endobronchial laser therapy, electrocautery, argon plasma coagulation, cryotherapy, and airway stenting. In patients with CAOI, the role of therapeutic bronchoscopy is not clearly defined, but many isolated reports in the literature described bronchoscopic intervention in combination with medical therapy as the initial management approach. In this paper, we present cases of CAOI that underwent bronchoscopic intervention as part of their management. We described the infectious etiology, locations, bronchoscopic findings and bronchoscopic modalities for airway management.

Vancomycin Trough and Acute Kidney Injury: A Large Retrospective, Cohort Study

BACKGROUND

The association between vancomycin trough (VT) and acute kidney injury (AKI) at the recommended doses remains controversial.

METHODS

The authors conducted a retrospective, observational cohort study of 500 adult patients who received vancomycin for ≥72 h. Data collected included 2 main predictors: average VT (including only VTs before the occurrence of AKI), first VT and other possible risk factors for AKI. The baseline characteristics/variables between patients with AKI and patients with no AKI were compared. Logistic regression models were used to develop multivariate models. The authors divided the patients into 4 subgroups: (1) VT <10, (2) 10 ≤ VT < 15, (3) 15 ≤ VT < 20 and (4) VT ≥20 µg/ml. All subgroups were compared to subgroup 2 (reference group).

RESULTS

AKI occurred in 12.85% of patients while on vancomycin. The incidence of AKI in subgroups 1-4 was 8.02, 13.61, 13.70 and 31.82%, respectively, using the first VT, that is significantly higher in subgroup 4. Using average VT, AKI incidence was 5, 10.38, 19.01 and 25.58%, respectively, that is significantly higher in subgroups 3 and 4. On multivariate logistic regression, average VT, first VT, average VT >15, first VT >15, methicillin-resistant Staphylococcus aureus infection and morbid obesity were significantly associated with increased incidence of AKI.

CONCLUSION

Clinicians should be careful when aiming for a VT >15 μg/ml as this is associated with increased incidence of AKI.

Histoplasmosis after solid organ transplant

BACKGROUND

To improve our understanding of risk factors, management, diagnosis, and outcomes associated with histoplasmosis after solid organ transplant (SOT), we report a large series of histoplasmosis occurring after SOT.

METHODS

All cases of histoplasmosis in SOT recipients diagnosed between 1 January 2003 and 31 December 2010 at 24 institutions were identified. Demographic, clinical, and laboratory data were collected.

RESULTS

One hundred fifty-two cases were identified: kidney (51%), liver (16%), kidney/pancreas (14%), heart (9%), lung (5%), pancreas (2%), and other (2%). The median time from transplant to diagnosis was 27 months, but 34% were diagnosed in the first year after transplant. Twenty-eight percent of patients had severe disease (requiring intensive care unit admission); 81% had disseminated disease. Urine Histoplasma antigen detection was the most sensitive diagnostic method, positive in 132 of 142 patients (93%). An amphotericin formulation was administered initially to 73% of patients for a median duration of 2 weeks; step-down therapy with an azole was continued for a median duration of 12 months. Ten percent of patients died due to histoplasmosis with 72% of deaths occurring in the first month after diagnosis; older age and severe disease were risk factors for death from histoplasmosis. Relapse occurred in 6% of patients.

CONCLUSIONS

Although late cases occur, the first year after SOT is the period of highest risk for histoplasmosis. In patients who survive the first month after diagnosis, treatment with an amphotericin formulation followed by an azole for 12 months is usually successful, with only rare relapse.