BACKGROUND: The Automated Fluorescent Immunoassay System (AFIAS) rotavirus assay (Boditech Med Inc., Chuncheon, Korea) is a new rapid antigen test for rotavirus detection. We evaluated the performance of this assay for detecting rotaviruses and their specific genotypes in clinical stool samples. METHODS: AFIAS rotavirus assay was performed in 103 rotavirus-positive and 103 rotavirus-negative stool samples (confirmed by both PCR and ELISA), and its results were compared with those of PCR, ELISA, and immunochromatographic assay (ICA). We evaluated diagnostic sensitivity/specificity, the detectability of rotavirus subtypes, lower limit of detection (LLOD), reproducibility, cross-reactivity, and interference of AFIAS rotavirus assay. RESULTS: Based on PCR and ELISA results, diagnostic sensitivity and specificity of the AFIAS rotavirus assay were both 99.0%. LLOD results showed that the AFIAS assay had sensitivity similar to or greater than ICA and ELISA. High reproducibility was confirmed, and no cross-reactivity or interference was detected. This assay could detect genotypes G1P[8], G2P[4], G3P[8], G4P[6], G4P[8], G8P[4], G8P[8], G9P[4], and G9P[8]. CONCLUSIONS: The AFIAS rotavirus assay showed high reproducibility, sensitivity, and specificity as well as excellent agreement with ELISA, PCR, and ICA. It detected the most common as well as unusual genotypes of rotavirus prevalent in Korea. It could be a useful on-site assay for rapid, convenient, and cost-effective detection of rotavirus infection.
Enzyme-Linked Immunosorbent Assay ; Gangwon-do ; Genotype ; Immunoassay* ; Immunochromatography ; Korea ; Limit of Detection ; Polymerase Chain Reaction ; Rotavirus Infections ; Rotavirus* ; Sensitivity and Specificity

BACKGROUND: Rotavirus is a major pathogen causing enteritis worldwide in children under five years of age. In recent years, immunochromatographic assay (ICA) has been widely used as a diagnostic test for rotavirus detection. This study aimed to compare and evaluate the performance of ICA-based rotavirus rapid test kits from two manufacturers. METHODS: Residual stool samples from a total of 130 children with acute enterocolitis from November 2017 to January 2018 were used. We compared the results of the two immunochromatographic methods (SD BIOLINE Rotavirus kit and GENEDIA Rotavirus Ag Rapid Test) with those of the currently used enzyme immunoassay method. RESULTS: Positive agreement, negative agreement, and total agreement rates between the SD BIOLINE rotavirus kit and the enzyme immunoassay were 98.0%, 100%, and 99.2%, respectively. Positive agreement, negative agreement, and total agreement rates between the GENEDIA Rotavirus Ag Rapid Test and the enzyme immunoassay were 96.0%, 100%, and 98.4%, respectively. CONCLUSIONS: Both rotavirus rapid test kits showed very good agreement with the conventional enzyme immunoassay. Therefore, it could be a useful test to detect rotavirus directly from stool samples in a short time.
Child ; Diagnostic Tests, Routine ; Enteritis ; Enterocolitis ; Humans ; Immunochromatography ; Immunoenzyme Techniques ; Methods ; Rotavirus

PURPOSE: Early detection of Mycoplasma pneumoniae is important for appropriate antimicrobial therapy in children with pneumonia. This study aimed to evaluate the diagnostic value of a rapid antigen test kit in detecting M. pneumoniae from respiratory specimens in children with lower respiratory tract infection (LRTI). METHODS: A total of 215 nasopharyngeal aspirates (NPAs) were selected from a pool of NPAs that had been obtained from children admitted for LRTI from August 2010 to August 2018. The specimens had been tested for M. pneumoniae by culture and stored at −70°C until use. Tests with Ribotest Mycoplasma® were performed and interpreted independently by two investigators who were blinded to the culture results. RESULTS: Among the 215 NPAs, 119 were culture positive for M. pneumoniae and 96 were culture negative. Of the culture-positive specimens, 74 (62.2%) were positive for M. pneumoniae by Ribotest Mycoplasma®, and 92 of the 96 (95.8%) culture-negative specimens were negative for M. pneumoniae by Ribotest Mycoplasma®. When culture was used as the standard test, the sensitivity and specificity of Ribotest Mycoplasma® were 62.2% and 95.8%, respectively. Additionally, the positive predictive value, negative predictive value, and overall agreement rates with Ribotest Mycoplasma® were 94.9%, 67.2%, and 77.2%, respectively. CONCLUSIONS: A positive test result of Ribotest Mycoplasma® suggests a high likelihood of culture-positive M. pneumoniae infection. However, a negative test result should be interpreted with caution because nearly one-third of negative test results reveal culture-positive M. pneumoniae infections.
Child ; Diagnosis ; Humans ; Immunochromatography ; Mycoplasma pneumoniae ; Mycoplasma ; Pneumonia ; Pneumonia, Mycoplasma ; Point-of-Care Systems ; Research Personnel ; Respiratory Tract Infections ; Sensitivity and Specificity

Blood group determination in dogs is an important factor in transfusion medicine to minimize immediate or delayed adverse reactions after red blood cells transfusion in small animal clinics. Dog erythrocyte antigen (DEA) 1 is the most important blood type due to its high degree of antigenicity causing acute transfusion adverse reactions. The aim of this study was to investigate the prevalence of DEA 1 in various dog breeds in Korea. As a result of testing 592 blood samples from more than 35 dog breeds, DEA 1 blood typing for each breed showed that 57.8% of Malteses, 63.3% of Poodles, 76.2% of Mastiff-like dogs, 72.5% of Pomeranians, 47.7% of Shih Tzus, 70.3% of mixed breeds, 60.0% of Yorkshire Terriers, and 71.4% of Beagles were DEA 1-positive. Miniature Schnauzers and Jindo breeds had a significantly high prevalence (100%) of DEA 1-positive dogs compared to that in other small breed dogs. This is the first report of immunochromatography-detected DEA 1 prevalence in various domestic dog breeds. Although additional studies need clarifying the potential blood transfusion risks in domestic breed dogs with DEA 1, the results of this study may be useful when selecting a blood donor.
Animals ; Blood Donors ; Blood Group Antigens ; Blood Grouping and Crossmatching ; Blood Transfusion ; Dogs ; Erythrocytes ; Humans ; Immunochromatography ; Korea ; Prevalence ; Transfusion Medicine ; Transfusion Reaction

The 2016–2017 surveys on the external quality assessment scheme for serologic tests for syphilis in Korea were conducted by the Korean Association of External Quality Assessment Service. Proficiency testing (PT) panels consisting of three pooled serum samples were shipped to 430 and 432 laboratories participating in the program in the 1st and 2nd trials of 2016 and 465 and 503 laboratories in the 1st and 2nd trials of 2017, respectively. The rates of returning results were 94.2% and 50.2% for non-treponemal and treponemal tests, respectively, in the 1st trial of 2016; 94.7% and 49.5% in the 2nd trial of 2016; 94.2% and 49.5% in the 1st trial of 2017; and 92.8% and 48.7% in the 2nd trial of 2017, respectively. The most commonly used methods for non-treponemal tests were rapid plasma reagin (RPR) card test, followed by RPR turbidoimmunoassay and venereal disease research laboratory tests. The most commonly used methods for treponemal tests were Treponema pallidum particle agglutination, followed by immunochromatographic assay, Treponema pallidum latex agglutination, chemiluminescence immunoassay, and fluorescent treponemal antibody-absorption. The accuracy rates of the 2017 PT for non-treponemal and treponemal tests were 92.5%–99.8% and 93.3%–100.0%, respectively, which were significantly lower compared to the 98.4%–100.0% and 97.0%–100.0% in 2016. A possible explanation for the lower accuracy rates in the 2017 PT survey is the matrix effect caused by pooling multiple individual serum samples. These data suggest that pooling of serum samples obtained from a small number of donors may help avoid the matrix effect affecting standard materials used for syphilis serology PT.
Agglutination ; Humans ; Immunoassay ; Immunochromatography ; Korea* ; Latex ; Luminescence ; Plasma ; Serologic Tests* ; Sexually Transmitted Diseases ; Ships ; Syphilis* ; Tissue Donors ; Treponema pallidum

Porcine reproductive and respiratory syndrome (PRRS) is recognized as one of the most important infectious diseases causing serious economic loss in the swine industry worldwide. Due to its increasing genetic diversity, a rapid and accurate diagnosis is critical for PRRS control. The immunochromatographic strip test (ICST) is a rapid and convenient type of immunoassay. In this study, an on-site immunochromatographic assay-based diagnostic method was developed for detection of PRRS virus (PRRSV)-specific antibodies. The method utilized colloidal gold nanoparticle-labeled dual-type nucleocapsid proteins encoded by open reading frame 7. We evaluated 991 field samples from pig farms and 66 serum samples from experimentally PRRSV-inoculated pigs. Based on true PRRSV-specific antibody-positive or
Agriculture ; Antibodies ; Colloids ; Communicable Diseases ; Diagnosis ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique ; Genetic Variation ; Gold Colloid ; Immunoassay ; Immunochromatography ; Immunoglobulin M ; Methods ; Nucleocapsid Proteins ; Open Reading Frames ; Porcine Reproductive and Respiratory Syndrome ; Porcine respiratory and reproductive syndrome virus ; Sensitivity and Specificity ; Swine

Leptospirosis is a febrile zoonotic disease. Routine diagnosis of leptospirosis is based on the detection of specific antibodies with serological tests. The aim of our study was to determine the usefulness of immunochromatographic assay (ICA), ImmuneMed Leptospira IgM Duo Rapid test kit from Korea, in rapid screening of acute leptospirosis in emergency cases with limited expertise. A total of 197 serum samples (93 positive, 104 negative) were selected randomly. The test has good diagnostic sensitivity 73% and specificity 90%. With positive predictive value of 87% and negative predictive value of 79%, this reassures patients have higher chance of correct diagnosis. This ICA is acceptable for screening of leptospirosis but confirmation with microscopic agglutination test should follow.
Agglutination Tests ; Antibodies* ; Diagnosis ; Emergencies ; Humans* ; Immunochromatography ; Immunoglobulin M* ; Korea ; Leptospira* ; Leptospirosis ; Mass Screening ; Sensitivity and Specificity ; Serologic Tests ; Zoonoses

As part of the immunoserology program of the Korean Association of External Quality Assessment Service, we organized two trials on the external quality assessment of hepatitis viral markers in 2016 and 2017. The hepatitis viral antigens and antibodies program consisted of 10 test items. We delivered two and three types of pooled sera specimens to 965 and 965 institutions for the first and second trials of external proficiency testing in 2016, respectively. The number of participating laboratories was 915 (94.8%) and 913 (95.0%) in the first and second trials in 2016, respectively. We also delivered three kinds of pooled sera specimens to 936 and 1,015 institutions for the first and second trials of external proficiency testing in 2017, respectively. The number of participating laboratories was 920 (98.3%) and 996 (98.1%) in the first and second trials in 2017, respectively. The most commonly tested items were hepatitis B surface antigen, followed by the antibodies to hepatitis B surface antigen, anti-hepatitis C virus, hepatitis B envelope antigen, antibodies to hepatitis B envelope antigen, anti-hepatitis A virus and antibodies to hepatitis B core antigen. The most frequently used methods for detecting viral markers were the chemiluminescence immunoassay and the electrochemiluminescence immunoassay, but they yielded a few-false positive results due to the matrix effect. The immunochromatographic assay yielded false-negative results for anti-hepatitis A virus due to low sensitivity. Continuous improvement in the quality of viral hepatitis testing through participation in the survey seems necessary.
Antibodies ; Antigens, Viral ; Biomarkers* ; Hepatitis A ; Hepatitis B ; Hepatitis B Core Antigens ; Hepatitis B Surface Antigens ; Hepatitis B virus ; Hepatitis C ; Hepatitis* ; Immunoassay ; Immunochromatography ; Korea* ; Laboratory Proficiency Testing ; Luminescence

PURPOSE: This study aimed to examine the accuracy of rapid influenza diagnostic tests (RIDT) in children with an influenza-like illness and to evaluate factors associated with greater accuracy. METHODS: Pediatric patients, who visited Hallym University Sacred Heart Hospital with an influenza-like illness between June 2011 and May 2016, were enrolled in this study. We tested 798 samples using a real-time polymerase chain reaction (PCR) for respiratory viruses and compared the results with rapid influenza tests. RESULTS: In comparison with the results of the multiplex PCR, the positive agreement rates of RIDT for influenza A and B virus were 75.7% and 60.0%, respectively. The performance of RIDT varied according to days after fever onset. The positive agreement rates of RIDT for influenza A and B tests, performed within 4 days of fever onset, were 77.6% and 73.2%, but the rates for tests performed more than 5 days after fever onset were 66.7% and 21.4%, respectively. CONCLUSIONS: The RIDT is a quick and simple aid to diagnosis, but is less sensitive than the labeled sensitivity. Moreover, test performance varied according to days after fever onset. Test specimens for RIDT should be collected as soon as possible after the onset of symptoms (less than 4 days).
Child ; Diagnosis ; Diagnostic Tests, Routine ; Fever ; Heart ; Herpesvirus 1, Cercopithecine ; Humans ; Immunochromatography ; Influenza, Human* ; Multiplex Polymerase Chain Reaction ; Orthomyxoviridae* ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction ; Seasons*

A simple and rapid immunochromatographic test strip incorporating a colloidal gold-labeled recombinant Nsp7 antigen probe was successfully developed for the detection of anti-porcine reproductive and respiratory syndrome virus (PRRSV) antibodies in swine. Recombinant Nsp7 protein of PRRSV labeled with colloidal gold was dispensed on a conjugate pad for use as the detector. Staphylococcal protein A and purified porcine anti-Nsp7 antibodies were blotted on a nitrocellulose membrane to form test and control lines, respectively. A comparison of the strip with standard diagnostic tests, enzyme-linked immunosorbent assays and immunoperoxidase monolayer assay, was also performed. The immunochromatographic test strip was shown to be of high specificity and sensitivity. Furthermore, the strip assay is rapid and easy to perform with no requirement for professional-level skills or equipment. It is suggested that the immunochromatographic test strip can be used to quickly and accurately detect PRRSV antibody and to be suitable for diagnostic purposes in the field.
Antibodies* ; Collodion ; Colloids ; Diagnostic Tests, Routine ; Enzyme-Linked Immunosorbent Assay ; Gold Colloid ; Immunochromatography ; Membranes ; Porcine Reproductive and Respiratory Syndrome* ; Porcine respiratory and reproductive syndrome virus* ; Sensitivity and Specificity ; Staphylococcal Protein A ; Swine