Result Patterns and Characteristics of HBeAg and HBV DNA in Patients with Chronic Hepatitis B

BACKGROUND: Discrepancies in the results between hepatitis B e-antigen (HBeAg) and hepatitis B virus (HBV) DNA levels pose difficulties in the management of chronic hepatitis B (CHB). This study aims to better understand the different phases of CHB and to detect additional meaningful parameters for CHB patients. METHODS: We collected datasets of HBeAg and HBV DNA levels measured during 2016 and the follow-up results for CHB patients for past 3 years. We analyzed the collected data by applying the definitions of CHB clinical phase and compared the results of semi-quantitative and quantitative HBeAg assays. RESULTS: About 55% of 2,291 result pairs from CHB patients showed qualitative agreement between HBeAg and HBV DNA results. HBeAg (−) CHB was reported in 16.49%, while hepatitis B surface antigen (HBsAg) loss occurred in 0.18% among 1,146 patients annually. HBeAg reversion occurred in 2.74% of 839 patients that experienced HBeAg seroconversion. Patients with HBeAg (+) and HBV DNA (−) showed statistically significant differences in the levels and percentage abnormality of alanine aminotransferase (ALT) based on whether HBV DNA was ‘Target not detected’ or ‘Detected,

Survey and Solutions for the Current Status of Quality Control in Small Hospital Laboratories

BACKGROUND: To prevent medically significant errors, hospital laboratories must perform thorough statistical quality control (QC) procedures. We surveyed the QC status of small laboratories and created new statistical QC software that they can easily use for improving QC. METHODS: A questionnaire on the status of external and internal QC was created and sent to clinics and hospitals with small-scale laboratories. We then created QC software that can be downloaded and installed for free. RESULTS: External quality assessments were performed in 32% of the clinics (22 of 66) and 52% of the hospitals (12 of 23). Seventy-three percent of all institutions (66 of 90) carried out an internal quality assessment based on their own guidelines, mostly using commercialized QC materials. However, only 52% of clinics and 23% of hospitals used their own acceptable range instead of the manufacturer's expected range. In addition, the proportion of manual QC management reached 52% in clinics and 82% in hospitals. The QC software we designed covers all the basic functions of statistical QC and aims to improve the quality of laboratories. CONCLUSIONS: We obtained basic data on the current status of external and internal QC in small-scale laboratories using this survey. Furthermore, we suggested that new QC software may actually help to improve QC of small laboratories.

Comparison of the QIAGEN artus HBV QS-RGQ Assay With the Roche COBAS AmpliPrep/COBAS TaqMan HBV Assay for Quantifying Viral DNA in Sera of Chronic Hepatitis B Patients

BACKGROUND: Hepatitis B virus DNA quantification is essential for managing chronic hepatitis B (CHB). We compared the performance of artus HBV QS-RGQ (QIAGEN GmbH, Germany) and CAP/CTM v2.0 HBV assays (Roche Molecular Diagnostics, USA) in CHB patients. METHODS: A comparative evaluation between two assays was performed with 508 clinical serum samples. Precision, linearity, and the limit of detection (LOD) of QS-RGQ assay was evaluated by using the WHO standard 97/750 and clinical samples. RESULTS: Detection rates and viral loads as determined QS-RGQ assay were significantly lower than those from the CAP/CTM v2.0 assay (52.8% vs 60.6%; 3.55±1.77 IU/mL vs 4.18±1.89 IU/mL, P<0.0001). The kappa coefficient between qualitative results was 0.79 (95% confidence interval, 0.74 to 0.85). Bland-Altman plot found a mean difference of (QS-RGQ − CAP/CTM v2.0)=−0.63 log₁₀ IU/mL (95% limit of agreement, −1.48 to 0.22). Repeatability and total imprecision (% CV) of the QS-RGQ assay were 1.0% and 1.1% at 2,000 IU/mL, and 0.7% and 1.4% at 20,000 IU/mL, respectively. Linearity of this assay ranged from 31.6 to 1.0±10⁷ IU/mL, and the LOD was 2.95 IU/mL. CONCLUSIONS: The artus HBV QS-RGQ assay showed good performance but significantly decreased detection rate and viral load compared with CAP/CTM v2.0 assays. This assay recommends using plasma; however, we used stored serum because of the retrospective study design. Usually HBV DNA quantification is performed in plasma or serum, but sample type and clinical relevance of quantitative values should be considered when determining the clinical application of this reagent.

Evaluation of Automated Assays for Measuring Serum Hyaluronic Acid: For the Diagnosis of Rheumatoid Arthritis

BACKGROUND: Hyaluronic acid (HA) is present in the connective tissues wherein it functions as a lubricant. HA is known to be increased in both synovial fluid and serum when inflammation occurs in the joint. We measured serum HA concentrations by automated assays and determined its reference interval and its usefulness as a diagnostic marker in patients with rheumatoid arthritis (RA). METHODS: Serum specimens collected from 121 healthy individuals and 253 patients with various arthritis were used for measuring HA with two automated assays, namely, LPIAACE (Mitsubishi, Japan) and LT Auto Wako (Wako, Japan). The association between serum HA concentration and the diagnosis of RA was estimated by receiver operator characteristic (ROC) analysis and multivariate logistic regression. RESULTS: The 95th percentile upper reference limit of serum HA was 57.28 ng/mL (90% confidence interval [CI], 46.30-68.20 ng/mL) for LPIAACE and 72.64 ng/mL (90%% CI, 57.30-85.70 ng/mL) for LT Auto Wako. Area under the ROC curve values of serum HA for discriminating the RA group from the non-RA group were 0.68 for LPIAACE and 0.70 for LT Auto Wako. The odds ratio for serum HA in predicting RA was 1.02 (95% CI, 1.02-1.04) for LPIAACE and 1.03 (95% CI, 1.02-1.05) for LT Auto Wako. CONCLUSIONS: This study provides a reference interval for serum HA concentrations in Koreans. This result suggests that the serum HA concentrations could be helpful as a complementary marker for discriminating RA from other types of arthritis, as well as distinguishing patients with RA from healthy controls.

Two Cases of Campylobacter jejuni Bacteremia from Patients with Diarrhea / 대한임상미생물학회지

Campylobacter jejuni commonly causes bacterial enteritis but rarely causes extraintestinal infection including bacteremia. We isolated C. jejuni from the blood culture of a 20-year-old man presenting with fever and headache and also from the blood culture of a 23-year-old man suffering abdominal pain and diarrhea. This organism grew in anaerobic culture, showed curved Gram-negative bacilli by Gram stain, and was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS).

Analysis of Polycheck Allergy Results of the Recent Two Years: Comparison with Skin Prick Test and ImmunoCAP

BACKGROUND: Multiple Antigen Simultaneous Test (MAST)-immunoblot assay is a practical and economical test, which has been recently introduced nationwide. Authors investigated test efficiency of a MAST-immunoblot assay, Polycheck Allergy (PA). METHODS: A total of 3,153 patients were tested by PA and the results were compared with the results of ImmunoCAP and skin prick test (SPT) in 532 and 75 patients, respectively. The correlation with the lgE results measured by VIDAS was also analyzed. RESULTS: The agreements of PA with SPT were 87.8% in the Inhalant Panel and 89.3% in the Food Panel and the agreement of ImmunoCAP with SPT was 95.2%. The most common allergens giving positive reactions were Dermatophagoides farinae (46.2%) and Dermatophagoides pteronyssinus (40.0%). SPT taken as a reference, PA compared with ImmunoCAP showed higher agreement (D. farinae, 76.0 vs. 70.7%; D. pteronyssinus, 76.0 vs. 74.4%), sensitivity (D. farinae, 72.7 vs. 68.2%; D. pteronyssinus, 75.0 vs. 71.2%) and specificity (D. farinae, 85.0 vs. 81.3%) except for the specificity for D. pteronyssinus (78.3 vs. 87.5%). The rate of allergen specific IgE positive patients was higher than that of negative patients when total IgE was over 100 kU/L. CONCLUSIONS: Our results showed that the agreement, sensitivity and specificity of PA were similar to or better than those of the previously established test, ImmunoCAP. The allergen specific IgE results of PA were in correlation with total IgE. PA may be used for testing allergen specific IgE to diagnose and treat allergic diseases.

Analysis of Polycheck Allergy Results of the Recent Two Years: Comparison with Skin Prick Test and ImmunoCAP

BACKGROUND: Multiple Antigen Simultaneous Test (MAST)-immunoblot assay is a practical and economical test, which has been recently introduced nationwide. Authors investigated test efficiency of a MAST-immunoblot assay, Polycheck Allergy (PA). METHODS: A total of 3,153 patients were tested by PA and the results were compared with the results of ImmunoCAP and skin prick test (SPT) in 532 and 75 patients, respectively. The correlation with the lgE results measured by VIDAS was also analyzed. RESULTS: The agreements of PA with SPT were 87.8% in the Inhalant Panel and 89.3% in the Food Panel and the agreement of ImmunoCAP with SPT was 95.2%. The most common allergens giving positive reactions were Dermatophagoides farinae (46.2%) and Dermatophagoides pteronyssinus (40.0%). SPT taken as a reference, PA compared with ImmunoCAP showed higher agreement (D. farinae, 76.0 vs. 70.7%; D. pteronyssinus, 76.0 vs. 74.4%), sensitivity (D. farinae, 72.7 vs. 68.2%; D. pteronyssinus, 75.0 vs. 71.2%) and specificity (D. farinae, 85.0 vs. 81.3%) except for the specificity for D. pteronyssinus (78.3 vs. 87.5%). The rate of allergen specific IgE positive patients was higher than that of negative patients when total IgE was over 100 kU/L. CONCLUSIONS: Our results showed that the agreement, sensitivity and specificity of PA were similar to or better than those of the previously established test, ImmunoCAP. The allergen specific IgE results of PA were in correlation with total IgE. PA may be used for testing allergen specific IgE to diagnose and treat allergic diseases.