Antigen Enzyme Research Articles

P-1206. Dengue Epidemic Outbreak 2023-2024: is it here for good? Experience in a Tertiary Care Pediatric Hospital in Buenos Aires, Argentina

Abstract Background Between epidemiological weeks (EW) 1 and 13 of 2024, the Region of the Americas reported 4,820,955 suspected dengue cases, triple the count from 2023. Argentina ranked second with 379,341 cases, a fourfold increase from the previous season. Our aim is to describe the behavior of dengue in a pediatric population during 2023 and 2024 and compare the characteristics of the latest two dengue outbreaks in Argentina. Methods Two cross-sectional studies were conducted in a children’s hospital in Buenos Aires City. Clinical, epidemiological, laboratory, and follow-up data were recorded for patients < 18 years with confirmed dengue, according to PAHO definitions. The first season period included from March to May 2023 (EW 11 to 20) and the second from January to April 2024 (EW 2 to 15). Results A total of 1145 suspected cases were attended. 565 (49%) patients with confirmed dengue were included. Median age: 11 years (IQR 9-14), 308 (54%) being male. Most common symptoms: fever (100%), median duration of 4 days (IQR 3-5); headache/retro-orbital pain (88%); myalgias (75%). 188 patients (33%) exhibited warning signs, the most common: mucosal bleeding, persistent vomiting and severe abdominal pain. 396 patients had leukopenia (71%) and 346 had elevated liver enzymes (62%). Thrombocytopenia (< 100,000/mm3) was found in 131 patients (24%). Significant differences were observed when comparing warning signs: more mucosal bleeding in 2024 (p< 0,001), and more abdominal pain in 2023 (p=0,023). Regarding diagnosis, 495 (88%) patients were confirmed by detectable RT-qPCR, serotype 2 predominated (57%) and was significantly most frequent in 2023 (p< 0,001). 70 (12%) patients had positive NS1 antigen enzyme immunoassay. 86 patients (15%) required hospitalization. 5 cases (0,8%) of severe dengue. No deaths occurred. Conclusion Timely and precise diagnosis, along with proper categorization of severity criteria, are crucial during dengue infection. One third of patients had warning signs. Despite serotype 2 being the most common during the 2023 outbreak, which is often linked with severe dengue, the hospitalization rate was the same in both periods. The new quadrivalent vaccine available could be an important tool to decrease the number of patients in our region. Disclosures All Authors: No reported disclosures

Magnetosomes as Potential Nanocarriers for Cancer Treatment.

Magnetotactic bacteria (MTBs) and their organelles, magnetosomes, are intriguing options that might fulfill the criteria of using bacterial magnetosomes (BMs). The ferromagnetic crystals contained in BMs can condition the magnetotaxis of MTBs, which is common in water storage facilities. This review provides an overview of the feasibility of using MTBs and BMs as nanocarriers in cancer treatment. More evidence suggests that MTBs and BMs can be used as natural nanocarriers for conventional anticancer medicines, antibodies, vaccine DNA, and siRNA. In addition to improving the stability of chemotherapeutics, their usage as transporters opens the possibilities for the targeted delivery of single ligands or combinations of ligands to malignant tumors. Magnetosome magnetite crystals are different from chemically made magnetite nanoparticles (NPs) because they are strong single-magnetic domains that stay magnetized even at room temperature. They also have a narrow size range and a uniform crystal morphology. These chemical and physical properties are essential for their usage in biotechnology and nanomedicine. Bioremediation, cell separation, DNA or antigen regeneration, therapeutic agents, enzyme immobilization, magnetic hyperthermia, and contrast enhancement of magnetic resonance are just a few examples of the many uses for magnetite-producing MTB, magnetite magnetosomes, and magnetosome magnetite crystals. From 2004 to 2022, data mining of the Scopus and Web of Science databases showed that most research using magnetite from MTB was carried out for biological reasons, such as in magnetic hyperthermia and drug delivery.

Diagnosis of Coccidioidomycosis with the Second-Generation Miravista IgG and IgM Enzyme Immunoassay and the Role of Adding Miravista Coccidioides Antigen Detection to Immunodiagnostic Assays.

In the present study, we validate and compare the second-generation Miravista Coccidioides IgG and IgM enzyme immunoassays (EIA) (MiraVista Diagnostics [MVD] Ab EIA) to Meridian Diagnostics Coccidioides IgG and IgM EIA (Meridian Ab EIA), immunodiffusion (ID) and complement fixation (CF). We also evaluated whether the addition of Coccidioides antigen testing to anti-Coccidioides antibody testing increased the sensitivity for the diagnosis of currently active coccidioidomycosis. We retrospectively studied 555 patients evaluated at Valleywise Health Medical Center between January 2013 and May 2017 for whom coccidioidomycosis was suspected and samples were submitted to MVD for testing. Specimens were tested for antigen in the MVD antigen enzyme immunoassay (MVD Ag EIA) and for IgG and IgM antibodies with MVD and Meridian Diagnostics EIAs. ID and CF were obtained from medical records. Sensitivity and specificity were 83.0% and 91.1% or MVD Ab EIA, 69.3% and 99.7% for Meridian Ab EIA, 85.4% and 100% for ID and 65.5% and 100% for CF. Combined MVD antigen and antibody detection by EIA and ID resulted in increased sensitivity in disseminated and pulmonary disease (MVD Ag/MVD Ab: 100%, 88.3%; MVD Ag/Meridian Ab: 98.2%, 78.6%; and MVD Ag/ID: 100%, 91.7%). The detection of antibodies by MVD EIA was more sensitive than Meridian EIA or CF but similar to ID. This study supports the use of antigen testing in immunocompromised patients and those with suspected disseminated disease. Furthermore, the addition of antigen detection by EIA to antibody detection resulted in higher sensitivity of all serological tests.

Detection of Histoplasma capsulatum and Blastomyces dermatitidis antigens in serum using a single quantitative enzyme immunoassay.

Histoplasma and Blastomyces antigen detection assays are commonly used diagnostic tools. However, a high level of cross-reactivity between these antigens prevents definitive pathogen identification by these assays alone. Retrospective analysis of 3,529 patients with Histoplasma and Blastomyces antigen testing performed on the same serum sample yielded an overall percent agreement of 99.3% (3,506 of 3,529; kappa: 0.859) between the two assays, suggesting that use of a single assay to detect both antigens may be an alternative diagnostic approach. We assessed performance of the Gotham BioTech Blastomyces antigen (GBA) enzyme immunoassay (EIA) (Portland, Maine) for detection of Blastomyces and Histoplasma antigens in serum. Comparison to the MiraVista Diagnostics Blastomyces (MVB) EIA showed 100% positive (24 of 24), negative (57 of 57), and overall (81 of 81) percent agreement. Additionally, 171 sera were used to compare the GBA EIA to the MiraVista Diagnostics Histoplasma (MVH) EIA, which showed 91.3% (63 of 69), 98% (100 of 102), and 95.3% (163 of 171) positive, negative, and overall percent agreement, respectively. Among eight patients with discordant GBA/MVH EIA results, seven had additional fungal testing performed, and results suggested that the MVH and GBA results were inaccurate for two and five samples, respectively. Overall, this study suggests that the GBA EIA has a high level of agreement with both of the commonly used, individual Blastomyces and Histoplasma antigen EIAs. By taking advantage of the high level of cross-reactivity between Blastomyces and Histoplasma antigen EIAs, utilization of a single antigen detection assay for these fungi provides an opportunity to optimize test utilization and decrease patient cost while maintaining a high level of diagnostic accuracy.

Sensitivity and performance of three novel quantitative assays of SARS-CoV-2 nucleoprotein in blood

To assess if SARS-CoV-2 (COVID-19) systemic disease can be determined by available nucleoprotein assays, we compared the performance of three commercial SARS-CoV-2 nucleoprotein (N) assays in plasma. A total of 272 plasma samples collected in the period November–December 2021 were analyzed by the methods Simoa SARS CoV‐2 N Protein Advantage Kit [Quanterix Simoa], Solsten SARS-CoV-2 Antigen enzyme immunosorbent assay (ELISA) [Solsten ELISA], and Elecsys SARS‐CoV‐2 Antigen electrochemiluminescence immunoassay [Elecsys ECLIA]. Additionally, a dilution series of inactivated virus culture was analyzed by the three assays. The SARS CoV-2 PCR-status was not known for the patients. Linear correlation in the pairwise correlation between assays as well as linearity of dilution series of inactivated virus culture was estimated by Spearman score. Sensitivity and specificity were estimated by pairwise comparison. The three assays showed poor agreement on patient samples with regards to concentration. Performance on virus culture was excellent but with different level of detection (LOD). Positive vs negative results show comparable sensitivity and specificity of Quanterix Simoa and Solsten ELISA, with a higher LOD in Elecsys ECLIA and thus lower sensitivity and high specificity. N by all tested assays can be used as a marker for systemic COVID-19 disease.

AN OVERVIEW ABOUT PREVALENCE OF FOOT AND MOUTH DISEASE VIRUS IN DISTRICTS KASUR AND LAHORE, PUNJAB, PAKISTAN FROM 2014-2019

During 2014-2019, 109 suspected samples for FMD were received at ELISA Lab Foot and Mouth Disease Center (F&MDRC) Lahore, Pakistan. These samples were collected from Lahore and Kasur districts of Punjab, Pakistan. The prevalence trend of three serotypes (A, O, Asia-1) was checked through antigenic Enzyme Linked Immunosorbent Assay (ELISA). From the processedfield samples; 71 samples were detected positive for serotype A, O and Asia-1. Out of the positive samples the most prevalent was serotype „A‟ (57.74%) followed by serotype Asia-1 (29.57%) and the least prevalent was serotype „O‟ (12.67%). The serotype „A‟ was more prevalent in Lahore (82.92%) as compared to Kasur (17.07%). For the period of 2014-2015, no case of serotype „O‟ was reported from district Kasur, whereas 9 cases were reported from district Lahore accordingly. Out of 21 cases of Asia-1 received at ELISA Lab FMDRC, Lahore; 18 cases were from Lahore followed by 3 cases from Kasur. From 2014-2019, the prevalence of serotype A, Asia-1 and O in Kasur was 70%, 30% and 0% respectively. The trend of prevalence in Lahore was same as in Kasur with most prevalent serotype A (55.73%) followed by serotype Asia-1 (29.50%) and the least prevalent was serotype O (14.75%). Theonly difference was that no case of serotype „O‟ reported in Kasur while in Lahore 9 cases were reported during the period of six years. In conclusion there are more cases of FMD reported in Lahore as compared to Kasur and prevalence from 2014-2016 is more as compared to years 2017-2019.

A novel, non-GMO surface display in Limosilactobacillus fermentum mediated by cell surface hydrolase without anchor motif

Recent studies have demonstrated the potential of surface display technology in therapeutic development and enzyme immobilization. Utilization of lactic acid bacteria in non-GMO surface display applications is advantageous due to its GRAS status. This study aimed to develop a novel, non-GMO cell wall anchoring system for lactic acid bacteria using a cell-surface hydrolase (CshA) from Lactiplantibacillus plantarum SK156 for potential industrial and biomedical applications. Analysis of the CshA revealed that it does not contain any known classical anchor domains. Although CshA lacks a classical anchor domain, it successfully displayed the reporter protein superfolder GFP on the surface of several lactic acid bacteria in host dependent manner. CshA-sfGFP fusion protein was displayed greatest on Limosilactobacillus fermentum SK152. Pretreatment with trichloroacetic acid further enhanced the binding of CshA to Lm. fermentum. The binding conditions of CshA on pretreated Lm. fermentum (NaCl, pH, time, and temperature) were also optimized, resulting in a maximum binding of up to 106 CshA molecules per pretreated Lm. fermentum cell. Finally, this study demonstrated that CshA-decorated pretreated Lm. fermentum cells tolerates gastrointestinal stress, such as low pH and presence of bile acid. To our knowledge, this study is the first to characterize and demonstrate the cell-surface display ability of CshA. The potential application of CshA in non-GMO antigen delivery system and enzyme immobilization remains to be tested.

Diversity of rotavirus strains circulating in Haiti before and after introduction of monovalent vaccine

BackgroundHaiti introduced a monovalent human group A rotavirus (RVA) vaccine (Rotarix) into its routine infant immunization program in April 2014. The goal of the surveillance program was to characterize RVA strains circulating in Haiti before and after RVA vaccine introduction. MethodsStool samples were collected from children <5 years old presenting with acute gastroenteritis at 16 hospitals in Haiti. RVA antigen enzyme immunoassay (EIA) testing was performed, and G and P genotypes were determined for positive specimens. In this study, genotype data for samples collected from May 2012 through April 2014 (the pre-vaccine introduction era) and May 2014 through July 2019 (post-vaccine introduction era) were analyzed. ResultsA total of 809 specimens were tested by the Centers for Disease Control and Prevention. During the pre-vaccine introduction era (May 2012 through April 2014), G12P[8] was the predominant genotype, detected in 88–94% of specimens. There was a high prevalence of the equine-like G3P[8] genotype among Haitian children with RVA after vaccine introduction. ConclusionsThe predominance of equine-like G3P[8] in three of five RVA seasons post-vaccine introduction suggests possible vaccine-specific selection pressure in Haiti. These temporal variations in RVA genotype predominance will require continued monitoring in Haiti as the vaccination program continues.

Risk Factor Assessment, Sero-Prevalence, and Genotyping of the Virus That Causes Foot-and-Mouth Disease on Commercial Farms in Ethiopia from October 2018 to February 2020

A cross-sectional serological, active outbreak search and a questionnaire-based survey were carried out to investigate foot-and-mouth disease (FMD) sero-epidemiology in Ethiopia. The circulating serotype of the FMD virus (FMDV) was identified, and the knowledge regarding FMD and husbandry practices was assessed. Using the questionnaire survey, a total of 237 individuals were interviewed, and the majority responded that there is no practice of reporting disease outbreak, free in and out movement of livestock, or share pastures, and they use traditional case management as a means of controlling the disease. A total of 1938 cattle, 490 domestic small ruminants, and 426 swine were sampled randomly for serological analysis using the 3ABC non-structural protein (NSP) enzyme-linked immunosorbant assay. An overall prevalence of 25% in cattle, 5% in domestic small ruminants, and 2% in swine was recorded. Multivariable logistic regression analysis revealed that cattle from the Oromia, Tigray, and Amhara regions had the highest probability of being sero-positive as compared with Addis Ababa odds ratio(OR)(OR: 4 (95% confidence interval (CI)(CI [3–6], 3 (95% CI [2,5]), and 2 (95% CI 2 [1,3]), respectively)). Older cattle (older than three years) and domestic small ruminants (&gt;18 months) had a higher chance of being seropositive (OR: 2, 95% CI [1.6,3]) and (OR: 6, 95% CI [2,18]), respectively). Female and older swine older than three years of age had a higher chance of being sero-positive (p &lt; 0.05). Local breed cattle had the lowest chance (OR: 0.2. 95% CI [0.1–0.3]) of being sero-positive. A region, age, and breed proved to have a statistically significant association with sero-positivity (p &lt; 0.05) in cattle. Swine from Bishoftu were less likely to test positive than swine from Addis Ababa (OR: 0.04, 95% CI [0.01–0.3]). From 96 herds, 72 pooled outbreak samples were analyzed by polymerase chain reaction (PCR), virus isolation, serotyping (antigen enzyme linked immunosorbant assay (ELISA)), sequencing, and phylogenetic tree analysis. Six serotype A (G-IV) FMD viruses and three serotype O east African (EA-3 and EA-4) FMDVs were identified. Thus, this study established the lack of disease outbreak reporting, poor husbandry problems, and the prevalence of FMD in three domestic species (cattle, small ruminant, and swine). In addition, continuous circulation of serotype A and O in the study area was confirmed.

Chemotherapeutic Evaluation of Ethanol Extract of Chromolaena odorata on Biochemical Aberrations Associated with Experimentally-induced Benign Prostatic Hyperplasia in Male Rats

The sudden rise in benign prostatic hyperplasia (BPH) cases, severe side effects, and the high cost of conventional methods have necessitated the intensive search for alternative BPH management strategies. This study investigated the restorative effects of ethanol leaf extract of Chromolaena odorata (EECO) on testosterone-induced BPH in male albino rats. Thirty male albino rats with a weight range of 150-210 g were randomly distributed into six groups of five rats each. Group 1 was normal rats and not induced. Groups 2-6 were induced via daily subcutaneous injection of testosterone propionate (3 mg/kg) for 28 days. After induction, group 2 received vehicle (carboxyl methylcellulose), group 3 received finasteride (1 mg/kg), while groups 4-6 received 100, 200, and 400 mg/kg of EECO, respectively, for 21 days orally. Prostate and biochemical parameters were determined using standard methods. Treatments with EECO decreased the concentrations of prostate-sensitive antigen, dihydrotestosterone, testosterone, malondialdehyde, cholesterol, low-density cholesterol, and liver enzyme activities compared with BPH-control. Furthermore, there was increased superoxide dismutase, and catalase activities in extract treated groups compared with BPH- control. The findings from this study showed that EECO inhibited testosterone-induced BPH anomalies, making it promising phytotherapy for the management of BPH in males.

Disseminated Rasamsonia argillacea species complex infections in 8 dogs.

BackgroundClinical features, treatment, and outcome of opportunistic infections with Rasamsonia spp., a nonpigmented filamentous mold, are not well documented in dogs.ObjectivesDescribe clinical, radiographic, pathologic features, and outcome of dogs with disseminated Rasamsonia species complex infections.AnimalsEight client‐owned dogs.MethodsRetrospective case series. Medical records were reviewed to describe signalment, history, clinicopathologic and imaging findings, microbiologic and immunologic results, cyto‐ and histopathologic diagnoses, treatment, and outcome.ResultsPresenting complaints were nonspecific with anorexia (n = 5) and back pain (n = 4) most common. Five dogs were German Shepherd dogs. Six dogs had multifocal discospondylitis and 2 had pleural effusion. Six dogs had Rasamsonia piperina and 2 had Rasamsonia argillacea infections with isolates identified using DNA sequencing. Rasamsonia spp. were isolated by urine culture in 5 of 7 dogs. Five of 6 dogs had positive serum Aspergillus galactomannan antigen enzyme immunoassay (EIA) results. Median survival time was 82 days, and 317 days for dogs that survived to discharge. Four died during initial hospitalization (median survival, 6 days). All isolates had low minimum effective concentrations (MECs) to echinocandins with variable minimum inhibitory concentrations (MICs) for azole antifungal drugs.Conclusions and Clinical ImportanceRasamsonia spp. infections in dogs are associated with multisystemic disease involving the vertebral column, central nervous system, kidneys, spleen, lymph nodes, lungs, and heart. The infection shares clinical features with other systemic mold infections and can be misidentified when using phenotypical microbiologic methods. Molecular techniques are required to identify the organism and guide appropriate antifungal treatment.

Serological detection of hepatitis B and D virus co-infection among patients attending a tertiary health facility at Maiduguri, Nigeria

BackgroundHepatitis D virus (HDV) is highly pathogenic, and clinical studies revealed that HDV infection aggravates the natural history of the underlying hepatitis B virus (HBV) infection by progression to cirrhosis that leads to early decompensation of liver function compared with HBV mono-infection. To determine the seroprevalence of HDV among HBsAg-seropositive patients and associated biochemical profiles at Maiduguri, Nigeria, a hospital-based cross-sectional study on 180 sera of patients positive for HBsAg by ELISA were evaluated for anti-HDV, hepatitis B envelop antigen, anti-HBs antibodies and liver enzyme profiles.ResultsHDV seroprevalence of 3.3% among 180 HBsAg-positive patients. Relatively higher seroprevalence of HDV was observed in males (4.3%) than in females (2.3%). The highest infection rate (20%) was obtained in patients ≥ 56 years. However, no significant association between positive anti-HDV seroprevalence and gender (p > 0.05). Of the 6 (3.3%) anti-HDV-positive patients, only 1 (16.7%) was positive for HBeAg while all were negative for anti-HBs antibodies. The mean level of liver enzyme level of AST and ALT of the anti-HDV-positive patients significantly differ from that of HBsAg mono-infected patients (p ˂ 0.05). However, no significant difference (p < 0.05) between the mean levels of liver enzymes of ALP in anti-HDV-positive and HBsAg mono-infected patients (p ˃ 0.05) was found.ConclusionThis study revealed a relatively low presence of HDV in HBsAg-positive patients. Furthermore, HDV-HBV co-infected patients had somewhat worse liver enzyme upregulation. This underscores the need for rapid HDV testing and treatment in HBV-infected patients.

Seroprevalence of Hepatitis B Virus Infection among the Tribal Population of Attapady, Kerala,India

Introduction: Hepatitis B Virus (HBV) infection remains a significant global health concern that may cause acute or chronic hepatitis. Chronically infected patients are at risk for cirrhosis and hepatocellular carcinoma. The disease causes a problem in the tribal communities. There are lack of studies on the prevalence of HBV among the tribal population. Aim: To assess the seroprevalence of HBV infection among the tribal population of Attapady, Kerala. Materials and Methods: This was a community based cross- sectional study conducted on serum samples collected from 269 subjects among the tribal population of Attapady. Serum samples were tested for quantitative antibody to HBsAg (anti-HBs), Hepatitis B surface antigen (HBsAg) and Hepatitis B envelope antigen (HBeAg) Enzyme Linked Immunosorbent Assay (ELISA). Total hepatitis B core antibody (anti-HBc) and IgM antibody to hepatitis B core antigen (anti HBc IgM), frequencies were obtained using proportion and 95% Confidence Interval CI. Results: The seroprevalence of HBsAg was 10.4%. HBeAg was detected in 7.1% of HBsAg positive patients. 21.2% had protective anti-HBs titer. Anti-HBe was detected in five patients. Anti-HBc total and anti-HBc IgM were positive for 26.7% and 2.6%, respectively. Anti-HBc IgM alone and isolated anti-HBc were detected in 1.5% and 5.9 %, respectively. Anti-HBs and anti-HBc total both became positive in 8.6% cases. Conclusion: HBV infection poses a huge burden on tribal health. All HBsAg positive patients should be tested further to determine the stage of the disease. There is need to explore high HBV prevalence areas with studies on associated risk factors to bring out the ongoing transmission process and focus on preventive measures. HBV vaccination, antenatal screening, and health awareness should be given priority to tackle the burden.

Evaluation of a novel monoclonal antibody-based enzyme immunoassay for detection of Histoplasma antigen in urine of dogs.

BackgroundCommercially available, noninvasive testing options for histoplasmosis are limited outside of the United States.ObjectivesTo describe the diagnostic performance of a novel Histoplasma antigen enzyme immunoassay (IM EIA) for the diagnosis of histoplasmosis in dogs.AnimalsTwenty dogs with histoplasmosis, 79 dogs without histoplasmosis, and 11 unclassified dogs providing 202 urine samples.MethodsThis a prospective study using stored urine samples. Samples were analyzed with the IM EIA and with the commercially available Histoplasma antigen EIA (MV EIA). Dogs were classified based on final proven diagnosis and performance of the IM EIA was described and compared with the MiraVista enzyme immunoassay (MV EIA).ResultsThe diagnostic sensitivity (DSe), specificity (DSp), and accuracy (DAc) of the IM EIA were 70% (51%‐89%), 99% (97%‐100%), and 93% (81%‐100%), respectively. The DSe, DSp, and DAc for the MV EIA were 95% (85%‐100%), 99% (97%‐100%), and 98% (95%‐100%), respectively. The area under the receiver operator characteristic curve was significantly smaller for IM EIA (0.87) as compared with MV EIA (0.97, P = .03). This was primarily due to 6 false negative IM EIA results, 4 from dogs with disease localized to the gastrointestinal tract. The MV EIA was positive in 5/6 of these dogs.Conclusions and Clinical ImportanceThe IM EIA might be useful for the diagnosis of disseminated histoplasmosis in dogs, but clinical usefulness will be limited in dogs with histoplasmosis localized to the GI tract.

Effect of an oral probiotic nutraceutical containing Aspergillus-derived ingredients on a serum and urine galactomannan antigen assay in dogs

A commercial Aspergillus galactomannan antigen (GMA) enzyme linked immunosorbent assay (ELISA) is used to support a diagnosis of systemic aspergillosis in dogs. In human patients, false positive results have been associated with administration of medications derived from molds. We sought to determine the effect of administration of a commercially available oral probiotic nutraceutical that contained Aspergillus-derived ingredients on serum and urine Aspergillus GMA levels in dogs by conducting a prospective, cross-over study. Galactomannan index (GMI) was measured on the solubilized probiotic nutraceutical and was positive (GMI ≥ 0.5) with a mean of 7.91. Serum and urine galactomannan indices were measured in 10 healthy dogs before (day 0) and after 1 week (day 7) of probiotic nutraceutical administration, then again 2 weeks after the probiotic nutraceutical was discontinued (day 21).Median (range) serum GMI were 0.19 (0.08–0.62), 0.22 (0.07–1.15) and 0.17 (0.14–0.63) at day 0, 7 and 21, respectively. Two of 10 dogs developed positive GMI (≥0.5) results after probiotic nutraceutical administration; however, no significant changes were noted over the study period. Median (range) urine GMI results were 0.06 (0.04–0.22), 0.07 (0.05–0.41) and 0.06 (0.03–0.16) at day 0, 7 and 21, respectively. A trend towards an increase urine GMI was noted between day 0 and 7 (P = 0.18), and decrease was noted between day 7 and 21 (P = 0.09). Administration of probiotics containing Aspergillus-derived ingredients to dogs did not reliably result in elevated Aspergillus GMA levels.

Screening for invasive fungal disease using non-culture-based assays among inpatients with advanced HIV disease at a large academic hospital in South Africa.

Despite widespread access to antiretroviral therapy (ART), the burden of advanced HIV disease in South Africa is high. This translates into an increased risk of AIDS-related opportunistic infections, including invasive mycoses. Using a limited number of non-culture-based diagnostic assays, we aimed to determine the prevalence of invasive mycoses and tuberculosis among hospitalised adults with very advanced HIV (CD4 counts<100cells/µL) at a large academic hospital. We conducted interviews and prospective medical chart reviews. We performed point-of-care finger stick and serum cryptococcal antigen lateral flow assays; serum (1 → 3) ß-D-glucan assays; urine Histoplasma galactomannan antigen enzyme immunoassays and TB lipoarabinomannan assays. We enrolled 189 participants from 5280 screened inpatients. Fifty-eight per cent were female, with median age 37years (IQR: 30-43) and median CD4 count 32cells/µL (IQR: 13-63). At enrolment, 60% (109/181) were receiving ART. Twenty-one participants (11%) had a diagnosis of an invasive mycosis, of whom 53% (11/21) had cryptococcal disease. Thirteen participants (7%) had tuberculosis and a concurrent invasive mycosis. ART-experienced participants were 60% less likely to have an invasive mycosis than those ART-naïve (adjusted OR: 0.4; 95% CI 0.15-1.0; P=.03). Overall in-hospital mortality was 13% (invasive mycosis: 10% [95% CI 1.2-30.7] versus other diagnoses: 13% (95% CI 8.4-19.3)). One in ten participants had evidence of an invasive mycosis. Diagnosis of proven invasive fungal disease and differentiation from other opportunistic infections was challenging. More fungal-specific screening and diagnostic tests should be applied to inpatients with advanced HIV disease.

HIV-Associated Histoplasmosis: Current Perspectives.

Histoplasmosis is an endemic mycosis caused by Histoplasma capsulatum. Infection develops by inhalation of microconidia from environmental sites inhabited by birds and bats. Disseminated disease is the usual presentation due to impaired cellular immunity. Common clinical manifestations include fever, fatigue, malaise, anorexia, weight loss, and respiratory symptoms. Histoplasma antigen detection is the most sensitive method for diagnosis. The sensitivity of the MVista® Quantitative Histoplasma antigen enzyme immunoassay is 95–100% in urine, over 90% in serum and bronchoalveolar lavage (BAL) antigen and 78% in cerebral spinal fluid (CSF). A proven diagnosis can be established by culture or pathology with sensitivities between 70% and 80%. The sensitivity of antibody detection by immunodiffusion or complement fixation was between 60% and 70%. Diagnosis using molecular methods has not been adequately validated for implementation and FDA cleared assays are unavailable. Liposomal amphotericin B should be used for 1–2 weeks followed by itraconazole for at least one year until CD4 counts are above 150 cells/mm3, HIV viral load is below 400 copies/mL and Histoplasma urine antigen is negative. Serum itraconazole level should be monitored to avoid drug toxicity. Antigen should be measured periodically to establish that treatment is effective and to assist in identifying relapse. The incidence of immune reconstitution inflammatory syndrome is low but it must be considered in patients who are thought to be failing antifungal treatment as it does not respond to changing antifungal agents but rather to initiation of corticosteroid therapy. In this review, we discuss pathogenesis, clinical manifestations, diagnosis and treatment based on personal experience and relevant publications.

Advances in Diagnosis of Progressive Pulmonary and Disseminated Coccidioidomycosis.

BackgroundAntibody detection is the main method for diagnosis of coccidioidomycosis, but it has limitations. The Coccidioides antigen enzyme immunoassay is recommended for testing cerebrospinal fluid in suspected meningitis. Reports on urine and serum antigen detection evaluated small numbers of patients who were mostly immunocompromised. The purpose of this study was to assess the accuracy of combined antibody and antigen detection for diagnosis.MethodsA retrospective study, including all patients in whom Coccidioides antigen detection in serum was performed between January 2013 and May 2017, was conducted at Valleywise Health Medical Center (formerly Maricopa Integrated Health System). Sensitivity and specificity of antigen and antibody were evaluated in 158 cases and 487 controls.ResultsThe sensitivity of antibody detection by immunodiffusion (ID) was 84.2%. The sensitivity of antigen detection was 57.0% if both urine and serum were tested and 36.7% if urine alone was tested. The sensitivity of combining antigen and ID antibody detection was 93.0%. The sensitivity of urine and serum antigen detection was 55.4% in proven and 58.7% in probable cases, 79.1% in disseminated and 41.6% in pulmonary cases, and 74.7% in immunocompromised and 40.0% in immunocompetent patients. Specificity was 99.4% for antigen detection and 96.5% for ID antibody detection. Diagnostic accuracy was 95.4% for ID antibody and antigen detection, 93.6% for ID antibody alone, and 89.1% for pathology or culture.ConclusionsThese findings support combined antibody and antigen detection for diagnosis of progressive coccidioidomycosis. The diagnosis may have been missed if antigen detection was not performed.

Fever in the returned traveller: the utility of the Platelia Dengue NS1 antigen enzyme immunoassay for the diagnosis of dengue in a non-endemic setting

Investigating fever in the returned traveller can be difficult and costly. Dengue is one of the most frequently reported aetiologies. NS1 is a non-structural dengue virus protein detectable during acute infection. The aim of this report is to describe the utility of the Platelia Dengue NS1 antigen enzyme immunoassay (EIA) for detection of dengue in a non-endemic region compared to a composite gold standard of contemporaneous molecular testing and seroconversion. We performed a retrospective analysis of all dengue serology tests from 6 February 2012 to 5 December 2018. Dengue serology and in-house flavivirus molecular results were identified using the laboratory information management system. Dengue serology was performed using the Bio-Rad Platelia Dengue NS1 antigen EIA, and Abbott Panbio Dengue IgG and IgM EIA. True positive NS1 result was defined as positive molecular test within one week of the positive NS1 result or seroconversion within 120 days. NS1 negative samples that remained negative to all dengue markers on repeat more than 10 and up to 120 days after were labelled as true negatives. More than 75% of cases had a serology pattern consistent with primary dengue. Sensitivity and specificity of NS1 Ag EIA was 96.4% (95% CI 92.3-98.7%) and 98.4% (95% CI 94.5-99.8%), respectively. Performance was poorer in serotype 4 infections (sensitivity 50%). Platelia Dengue NS1 antigen EIA test performance in the returned traveller cohort fulfils the remit as a single diagnostic test for acute dengue infection.

Endoplasmic Reticulum Aminopeptidase 1 beyond Antigenic Peptide-Processing Enzyme in the Endoplasmic Reticulum.

Endoplasmic reticulum aminopeptidase 1 (ERAP1) is well known as a processing enzyme of antigenic peptides, which are presented to major histocompatibility complex (MHC) class I molecules in the lumen of endoplasmic reticulum. Besides antigen processing, ERAP1 performs multiple functions in various cells depending on its intracellular and extracellular localization. Of note is the secretion of ERAP1 into the extracellular milieu in response to inflammatory stimuli, which further activates immune cells including macrophages and natural killer cells. Furthermore, secreted ERAP1 enhances the expression of pro-inflammatory cytokines like tumor necrosis factor-α, interleukin-1β, and interleukin-6. Such findings indicate that ERAP1 plays a significant role in the field of innate and acquired immunity. This review summarizes the functional analyses of ERAP1 that support our current understanding of its role as more than an antigenic peptide-processing enzyme, specifically emphasizing on its secretory form.