bluuebunny/crossref_metadata_2025_split huggingface dataset:
721. Diagnosis of Histoplasmosis Using the MVista Histoplasma Galactomannan Antigen Qualitative Lateral Flow-Based Immunoassay; A Multicenter Study
Authors: Abdallah Wassim , Myint Thein , LaRue Richard W , Minderman Melissa , Gunn Suphansa , Wheat Lawrence J , Hage Chadi A 
Published: December 2021

Abstract

Background
Accurate and timely methods for the diagnosis of histoplasmosis in endemic resource-limited settings are largely lacking. Histoplasma galactomannan antigen detection by enzyme immunoassay (EIA) is the most widely used method for the diagnosis of acute pulmonary and disseminated histoplasmosis in the United States (USA). EIA methods have constraints in resource-limited settings including cost, turnaround time, and the need for large reference laboratories, leading to missed or delayed diagnoses and poor outcomes. Lateral flow assays (LFA) are practical methods that can be used in this setting for Histoplasma antigen detection.

Methods
Frozen urine specimens were submitted to MiraVista (MVista) for Histoplasma antigen EIA testing from three academic medical centers in highly endemic areas of the USA. They were also blinded and tested for the MVista Histoplasma LFA by skilled MVista technologists. Medical records were reviewed for clinical information. Patients were classified as controls or cases of histoplasmosis. Cases were divided into proven or probable, pulmonary, or disseminated, immune competent or immune suppressed, and mild, moderate, or severe.

Results
352 subjects were enrolled, including 66 cases of histoplasmosis (44 proven, 22 probable) and 286 controls. Most of the cases were immunocompromised (68%). 76% had disseminated histoplasmosis. 6% were mild, 66% moderate, and 28% severe. A high degree of concordance was found between LFA and EIA results (kappa 0.837, OR 372.7, LR 204, p&lt; 0.001). Overall, the sensitivity and specificity of the LFA were 78.8% and 99.3% respectively (kappa 0.84, p&lt; 0.001). The sensitivity was higher in proven cases (93.2%), in patient with disseminated (94.7%), moderate (80%) and severe disease (94%), and those with galactomannan levels ≥ 2 ng/mL (97.7%). Specificity was 99.3% in proven cases, 99.3% in patient with moderate and severe disease, and 96.4% in those with galactomannan levels ≥ 2 ng/mL.
Table 1. Statistical characteristics of the LFA test for histoplasmosis in different categories. PPV: Positive Predictive Value. NPV: Negative Predictive Value. EIA: Enzyme Immunoassay.

The LFA test for histoplasmosis is more accurate in patients with high burden of infection.

Conclusion
The MVista Histoplasma galactomannan LFA may meet the need for accurate rapid diagnosis of histoplasmosis in resource-limited settings, especially in patients with relatively high disease burden, potentially reducing morbidity and mortality.

Disclosures
Melissa Minderman, Bachelor's Degree, Molecular Biology, MiraVista Diagnostics (Employee) Suphansa Gunn, Bachelor's Degree, psychology, MiraVista Diagnostics (Employee) Lawrence J. Wheat, MD, MiraVista Diagnostics (Employee)
722. Parasitic and Non-Parasitic Causes of Eosinophilia in Children Presenting to a Tertiary Care Center in the United States
Authors: Ness Tara , Erickson Timothy , Diaz Veronica , Hajjar Joud , Anvari Sara , Weatherhead Jill E 
Published: December 2021

Abstract

Background
Peripheral eosinophilia can be caused by many underlying conditions, including infectious pathogens, allergic disorders, neoplastic disorders, and immunological disorders. However, uncovering the cause of eosinophilia in children can be challenging due to the wide differential diagnosis.

Methods
To identify causes and risk factors of eosinophilia in children, we performed a retrospective chart review of children presenting to Texas Children’s Hospital in Houston, TX with peripheral eosinophilia from January 1, 2011 to December 31, 2019. Eosinophilia was classified as mild (absolute eosinophilia count or AEC &gt;500 and &lt; 1500), moderate (AEC &gt;1500 and &lt; 5000) and severe (AEC &gt; 5000). Demographic information in addition to travel history, co-morbid conditions, and diagnostic workup were collected.

Results
A total of 773 patients under 18 years of age were evaluated. The most common cause of eosinophilia in children was atopy (N=343, 44%), followed by eosinophilia of unknown etiology (N=227, 29%). Infectious pathogens were the etiology in 8% of cases of which all were parasitic pathogens. Helminthic (n=48, 79% of parasitic diseases in total) pathogens were more common than protozoan (n=13, 21% of parasitic diseases in total) and patients with parasitic infections had higher median eosinophilia compared to other subgroups (median = 1661, range 512-17,501) with the majority having moderate to severe eosinophilia (57%). The most common helminth was Toxocara (n=31), followed by Strongyloides (n=15), and, more rarely, pinworms (n=4). The most common protozoa identified was Dientamoeba fragilis (n=9), followed by Giardia species (n=5), Endolimax nana (n=4), Blastocystis species (n=3), and Iodamoeba butschlii (n=1). Many unknown cases had limited workup that did not include investigations for common parasites.

Conclusion
While atopy and unknown etiology were the most common diagnoses for children presenting with eosinophilia, parasites were relatively common and should be considered in the differential when investigating etiologies for peripheral eosinophilia.

Disclosures
Joud Hajjar, MD, MS, Baxalta (Grant/Research Support)Horizon (Advisor or Review Panel member)Pharming (Advisor or Review Panel member)
723. Cryptosporidium Detection in Preserved Stool Specimens: A Comparison Study of EIA, DFA, and Direct Microscopic Method
Authors: Bao Jian R , Master Ronald N , Jones Robert S , Clark Richard B , Shier Kileen L 
Published: December 2021

Abstract

Background
Cryptosporidium is an intestinal parasite that may cause diarrhea. Laboratory diagnosis largely relies on microscopic or immunology-based antigen detection. Direct fluorescent antibody (DFA) is considered the gold standard. Enzyme immunoassay (EIA) is an attractive alternative, but direct comparison studies for the performance together with the impact from different specimen preservation media are limiting.

Methods
We compared these three methods for the detection of Cryptosporidium oocysts (direct microscopic) or antigen (DFA or EIA) from stool samples preserved in either 10% buffered formalin, Cary-Blair/C&S, or Total Fix (MCC, Torrance, CA). The DFA from Meridian Bioscience (Cincinnati, OH) and the EIA using CRYPTOSPORIDIUM II (TechLab®, Blacksburg, VA) were performed according to the manufacturer’s instructions. The direct microscopic method was performed according to laboratory protocols, including direct wet mount, modified acid-fast stain, or permanent trichrome stain.

Results
A total of 140 samples, including 116 clinical specimens, 20 validation panel samples and 4 proficiency survey specimens, were examined (Table 1). The DFA and EIA methods produced 100% concordant results using all three preservatives, while the microscopic method had decreased sensitivity. All microscopic positives remained positive for both the DFA and EIA. Cross-reactivity from other parasites, such as Giardia, of the two immunoassays was not observed.

Conclusion
While the two immunological methods both outperformed the microscopic method, the EIA has the advantages of being objective, simple to perform, has less hands-on time, and thus makes it an attractive option for high throughput Cryptosporidium detection.

Disclosures
Kileen L. Shier, PhD, D(ABMM), MLS(ASCP)CM, Quest Diagnostics (Employee)
726. Operational Impact of Infectious Disease Threats During Military Travel
Authors: Boatwright Michael A , Utz Gregory , Kunz Anjali , Colombo Rhonda E , Fraser Jamie , Kuo Huai-Ching , Tribble David , Lalani Tahaniyat 
Published: December 2021

Abstract

Background
We evaluated the incidence and operational impact of travelers’ diarrhea (TD), influenza-like illness (ILI) and undifferentiated febrile illness (FI) in US active duty (AD) personnel traveling outside the continental U.S for deployment (DEP), joint military training exercises (EXR) or other military travel (e.g. Temporary Duty Travel) (TDY).

Methods
AD personnel traveling for ≤ 6.5 months were prospectively enrolled between 2010-2019. Participants completed a post-travel survey regarding risk behaviors, illnesses and impact on daily activities. Trip purpose was categorized into DEP, EXR, TDY and syndromic definitions were used to identify cases of TD, ILI and FI based on symptoms. A multivariate logistic regression model with backward selection was used to determine the odds ratio associated with partial or complete incapacitation due to infections (a composite endpoint of either TD, ILI or FI).

Results
1822 servicemembers were enrolled: 36.2% traveled on DEP, 36.2% for EXR and 27.7% for TDY (Table 1). 83.5% of personnel traveling for DEP were Special Operations and Marine units, and 82% of the EXR group participated in Pacific Pathways. Overall, 19% of US personnel experienced infections associated with partial or complete incapacitation (median duration of incapacitation- TD: 1 day; ILI: 4 days; FI: 3 days). DEP personnel had a longer travel duration and the highest rate of partial or complete incapacitation due to TD, ILI or FI (Figure 1 and 2). Risk factors associated with partial or complete incapacitation due to infections were non-adherence with malaria chemoprophylaxis (OR: 1.7 [95%CI:1.2-2.4]), close contact with locals (OR:1.7 [95%CI:1.3-2.2]), inability to clean hands regularly before meals (OR: 1.7 [95%CI: 1.3-2.3]), fresh water or rodent exposure OR: 1.4 (95%CI:1.1-1.9) and consuming street vendor food (OR:1.8 [95%CI:1.3-2.4]).
Table 1. Demographic and travel characteristics of AD personnel traveling outside the continental US.

Proportion of AD servicemembers that experienced TD, ILI or undifferentiated febrile illness during DEP, EXR, TDY (p&lt;0.05 for the comparison of each illness between DEP, EXR and TDY).
Figure 2.

Proportion of AD personnel with partial or complete incapacitation due to TD, ILI or FI during DEP, EXR or TDY (p &lt; 0.05 for the comparison of each illness between DEP, EXR and TDY).

Conclusion
Infectious disease syndromes are common during overseas military travel. TD had the highest negative impact on military travel especially among DEP personnel. We identified several modifiable risk factors associated with incapacitating infections which can be used to inform preventive and treatment strategies.

Disclosures
All Authors: No reported disclosures
729. Lassa Fever Associated Hearing Loss
Authors: Ficenec Samuel , Grant Donald , Emmett Susan , Schieffelin John 
Published: December 2021

Abstract

Background
Hearing loss (HL) is the second leading cause of disability affecting approximately 19% of the world’s population. Despite well known social, economic, and neurologic consequences this condition receives little attention. Lassa Fever (LF) was noted to be associated with HL shortly after its discovery in the 1970’s. However, the true burden of this sequelae is likely underestimated due to a lack of standardized measurement and reporting.

Methods
We performed a cross-sectional study of LF survivors and household controls in Kenema, Sierra Leone. Upon recruitment, survivors and controls were screened for HL by determining Pure Tone Averages (PTA) of air conduction thresholds using an AMBCO audiometer, according to WHO standards. Individuals found to have elevated PTAs were referred to confirmatory testing measuring both air and bone thresholds using a SHOEBOX audiometer to differentiate sensorineural and conductive HL. All subjects completed symptom questionnaires and physical exams to understand the full spectrum of viral sequelae.

Results
94 LF survivors and 281 controls were recruited. The average age of LF survivors was higher than controls (32.9 vs 28.7, p=0.008). Of these 94 LF survivors, 40 (43%) were found to have HL in comparison to 40 (14%) of controls (p&lt; 0.001). Lassa fever survivors were also found to have significantly worse HL with 16 (40%) found to have profound HL compared to only 2 (5%) of controls (p&lt; 0.001). Logistic regression of this cohort found that LF infection (OR = 1.30, p&lt; 0.001), any inner or middle ear symptoms (OR = 1.20, p=0.041), or pharyngeal symptoms (OR = 1.23, p=0.012) were significant risk factors of developing HL (p&lt; 0.001). Interestingly the development of any pulmonary symptoms was protective of HL (OR = 0.86, p=0.039). Animal model studies suggested that LF infection may result in the development of an ANCA vasculitis which may be causative of LF sequelae. A subset of LF survivors (n=80) and IgG negative controls (n=9) were tested for ANCA proteins, of these 20 (25%) survivors vs 5 (55%) tested positive with mean concentrations of 202.4 µg/ml and 135.7 µg/ml (p=0.449), respectively.

Conclusion
This data further characterizes the sequelae of LF and suggests mechanisms of pathogenesis of symptoms.

Disclosures
All Authors: No reported disclosures
731. Puerperal Sepsis Among Women with In-facility Births in Western Tanzania
Authors: Smith Rachel , Ruiz Alicia , Westercamp Matthew , Maro Godson , Serbanescu Florina 
Published: December 2021

Abstract

Background
Puerperal sepsis is an important cause of maternal mortality worldwide. As access to emergency obstetric services expands in resource-limited settings, rapid recognition and treatment of sepsis, and prevention of nosocomial infections that might lead to sepsis, is critical. We describe puerperal sepsis cases among women with in-facility births in the Kigoma region of Tanzania.

Methods
Demographic, obstetric history, pregnancy complication and outcome, as well as mortality data were collected for women who delivered in hospitals, health centers and dispensaries in the Kigoma region, Tanzania 2016 – 2018. Up to 3 maternal complications were recorded as free text. Puerperal sepsis included women where ‘sepsis’ was recorded as a complication during hospitalization. We calculated rates of puerperal sepsis and completed a descriptive analysis of patients.

Results
203,604 women delivered infants in 197 participating facilities during the data collection period. Of these, 2228 (1.1%) had sepsis recorded, for an overall rate of 10.9 sepsis cases per 1000 deliveries. Although 48% of births occurred in dispensaries, sepsis complications were reported almost exclusively in hospitals and health centers (37.7 and 10.3 per 1000 deliveries, respectively). Sepsis rates varied across individual facilities, from 15.5 to 45.2 cases per 1000 deliveries in hospitals and 0 to 38.6 cases per 1000 deliveries in health centers. Women who developed sepsis had a median age of 25 (IQR 22 – 30) years and 1113 (56%) were nulliparous. 1763 (90%) of women who had sepsis delivered by caesarian delivery. Obstructed labor (827; 42%) was a common co-complication of sepsis; obstetric hemorrhage and uterine rupture were seen in 93 (5%) and 77 (4%) women with sepsis, respectively. 49 women with sepsis (3%) died prior to hospital discharge. Stillbirths and pre-discharge neonatal deaths complicated 107 (5%) and 74 (4%) deliveries to women with sepsis.

Conclusion
In the Kigoma region of Tanzania puerperal sepsis frequently occurs in women with obstructed labor and caesarian delivery. Further evaluation of both facility-level and individual factors that contribute to the incidence of sepsis in this population, particularly those related to invasive procedures, is critical for early recognition and prevention. issue

Disclosures
All Authors: No reported disclosures
732. Sensitivity and Specificity of Point of Care Lung Ultrasound vs. Chest X-Ray for the Diagnosis of Pediatric Pneumonia in Limited resource settings: The Zambia Experience
Authors: Camelo Ingrid Y , Pieciak Rachel , castro-aragon Ilse , Setty Bindu , Etter Lauren , Wang Kaihong , Gill Christopher 
Published: December 2021

Abstract

Background
Pediatric pneumonia is the leading cause of child mortality in low-income countries. Pneumonia diagnosis is a challenge. Chest x-ray (CXR) is considered the gold standard, but it exposes children to ionizing radiation, and access to CXR is limited to hospital settings. Lung Point of Care Ultrasound (POCUS) is a portable and non-radiating alternative to CXR.

Methods
We enrolled 200 children aged 1-59 months from the University Teaching Hospital (UTH) Emergency Department (ED) in Lusaka, Zambia who met the WHO (World Health Organization) case definition for severe pneumonia. From each child, we collected demographic and clinical data, a CXR, and a set of ultrasound images using a Butterfly ultrasound probe. Images were independently interpreted by two radiologists blinded to the results of the other imaging modality. Using CXR as the gold standard, we determined the sensitivity and specificity, positive and negative predictive values, and likelihood ratios for pneumonia using lung POCUS.

Results
This preliminary analysis included 50 children seen between May-October 2020. Median age (9 months) (Range 4-15). 58% were male, (29/50). Median temperature was 37.3⁰C (range 36.5-38.0); median respiratory and pulse rates were 41 breaths/min (range 31-50) and 139 beats/min (range 124-160) respectively; median SpO2 on RA was 91% (range 89-95). 50% of cases had difficulty breathing (82%, 41/50); chest retractions (70%, 35/50) and grunting (62%, 31/50). Ultrasound images for 49/50 (98%) cases and CXRs for 50/50 (100%) of cases we analyzed. Sensitivity of lung POCUS in the detection of CAP was 61% (95% Cl: 0.52-0.84). The specificity was 77% (95% Cl: 0.56-0.91). Positive predictive value (PPV) 70% (95% CI: 0.62-0.94) and negative predictive value (NPV) 69% (95% CI: 0.56-0.79).

Conclusion
Preliminary findings of this study demonstrated the lower diagnostic accuracy of lung POCUS versus CXR in the detection of pneumonia in children 1- 59 months. The high specificity of the test will aid in ruling out severe pneumonia in children. Due to its availability, ease of interpretation, and absence of radiation exposure, lung POCUS should still be considered as an important initial imaging tool for the diagnosis of CAP in children in limited-resource settings.

Disclosures
All Authors: No reported disclosures
733. Carbapenem-Resistant Enterobacterales (CRE) Colonization Prevalence in Botswana: an Antibiotic Resistance in Communities and Hospitals (ARCH) Study
Authors: Mannathoko Naledi , Mosepele Mosepele , Smith Rachel , Gross Robert , Glaser Laurel , Alby Kevin , Richard-Greenblatt Melissa , Sharma Aditya , Jaskowiak Anne , Sewawa Kgotlaetsile , Reesey Emily , Cowden Laura , Cressman Leigh , Otukile Dimpho , Paganotti Giacomo , Mokomane Margaret , Lautenbach Ebbing 
Published: December 2021

Abstract

Background
Although CRE are a global threat, data in low- and middle-income countries are scarce. Colonization data are vital for informing antibiotic resistance strategies. We characterized the colonization prevalence of CRE in various settings in Botswana.

Methods
This study was conducted in 3 districts in Botswana (1 hospital and 2 clinics per district). Adult inpatients and clinic patients were randomly selected for enrollment. Community subjects were enrolled by inviting each enrolled clinic subject to refer up to 3 adults. Each adult clinic or community subject was also asked to refer their children. All subjects had rectal swabs obtained and inoculated on selective chromogenic media for preliminary identification of CRE. Final identification and susceptibility testing were performed using MALDI-TOF MS and VITEK-2, respectively. CRE underwent genotyping for carbapenemase genes.

Results
Subjects were enrolled from 1/15/20-9/4/20 with a pause from 4/2/20-5/21/20 due to a countrywide COVID lockdown. Of 5,088 subjects approached, 2,469 (49%) participated. Enrollment by subject type was: hospital – 469 (19%); clinic – 959 (39%); community adult – 477 (19%); and community child – 564 (23%). Of 2,469 subjects, the median (interquartile range) age was 32 years (19-44) and 1,783 (72%) were female. 42 (1.7%) subjects were colonized with at least one CRE; 10 subjects were colonized with multiple strains. E. coli (n=17), K. pneumoniae (n=20), and E. cloacae complex (n=11) were most common. CRE colonization prevalence was 6.8% for hospital subjects, 0.7% for clinic subjects, 0.2% for adult community subjects, and 0.5% for child community subjects (p&lt; 0.001)). CRE prevalence varied across regions (Figure 1) and was significantly higher pre- vs post-lockdown (Figure 2). VIM and NDM were the most common carbapenemase genes (Figure 3).
Figure 1. CRE Colonization - Study Sites

Figure 2. CRE Colonization - Temporal Trends

FIgure 3. CRE Genotypic Analyses

Conclusion
CRE colonization was significantly higher in hospital vs community settings in Botswana. CRE prevalence varied by region and decreased significantly following a countrywide lockdown. With CRE prevalence still modest, elucidating risk factors for CRE colonization holds promise in developing strategies to curb further emergence of CRE. Additional investigation of the CRE isolates without identified resistance genes is warranted.

Disclosures
Robert Gross, MD, MSCE, Pfizer (Other Financial or Material Support, Serve on DSMB for drug unrelated to HIV) Ebbing Lautenbach, MD, MPH, MSCE, Merck (Other Financial or Material Support, Member of Data and Safety Monitoring Board (DSMB))
734. Abnormal Lipid Profiles in Human Babesiosis
Authors: Mann Inderjit , pham Sophia , Spector Rachel , Papamanoli Aikaterini , Garry Evan , Lamba Pooja , Krivacsy Sara , Lum Michael D , Zahra Aleena , Hou Wei , Spitzer Eric , Marcos Luis A 
Published: December 2021

Abstract

Background
Babesiosis has gained attention as an emerging protozoal zoonotic disease with an expanding known incidence and geographical range in the US. The infection is caused by Babesia microti in the US and is transmitted by the bite of Ixodes ticks, and occasionally by blood transfusion. The diagnosis is usually established by microscopic examination of a stained blood smear to see intraerythrocytic organisms. The level of parasitemia is only loosely correlated with clinical severity. Anecdotal reports suggest that HDL cholesterol levels decline during acute babesiosis. In this study, we report cholesterol levels in a series of patients with acute babesiosis with the hypothesis that HDL levels may be a potential biomarker for more severe infections.

Methods
A retrospective chart review was performed at Stony Brook University Hospital and Stony Brook Southampton Hospital between 2013 and 2018. Inclusion criteria was defined as a case of acute Babesia infection proven by peripheral blood smear microscopy and who had a lipid profile drawn during presentation to the emergency department. Cholesterol levels that were measured either before or after the infection (at least 1 month apart) were also recorded to compare to the levels reported during acute infection.

Results
A total of 40 patients (27.5% female) met criteria for acute Babesia infection. Fifteen (37.5%) had a history of splenectomy. The patients were divided into two groups for comparisons based on the treating physician’s clinical decision: 32 patients who were admitted to the hospital and 8 patients who were not-admitted. History of hypertension was more common in admitted than non-admitted patients (37% vs. 17%, Chi-square test p=0.02); the median levels of LDL and HDL were more reduced in admitted than non-admitted patients (46 vs 76 mg/dL, p=0.04 and 9 vs 28.5 mg/dL, p=0.03, based on t-test respectively)

Conclusion
LDL and HDL levels are significantly reduced in acute babesiosis, and LDL levels are inversely proportional to the parasitemia, suggesting that low levels of LDL may predict worsening disease in babesiosis. The mechanism of this phenomenon is unknown. Further prospective studies are needed.

Disclosures
All Authors: No reported disclosures