BACKGROUND: Quality control is important for accurate diagnosis of human immunodeficiency virus (HIV) infection, and proficiency testing with external quality controls is an important part of quality control. This study intended to develop and supply customized external quality controls for HIV antigen/antibody testing fitted with currently used reagents for standardization of HIV infection diagnosis and evaluation of HIV testing competency of laboratories in Korea. METHODS: Serological tests and inactivation were performed on the obtained HIV antibody positive plasma. To manufacture quality controls having the required antibody titers, dilution ratio was searched using VIDAS (bioMérieux, France), Architect (Abbott Laboratories, USA), and Cobas 8000 (Roche Diagnostics, Germany) analyzers. Diluted source plasma was divided into aliquots after filtering. Homogeneity and stability of the produced external quality controls were evaluated. RESULTS: The collected HIV antibody positive plasma was confirmed by Western blot. Dilution ratios for source plasma were produced for each analyzer showing signal-to-cut-off 2–3, 5–7, and 15–16 reactivity. Diluted plasma was made to 1 mL aliquots and total set of 1,500 external quality controls for HIV antigen/antibody were manufactured. Produced controls satisfied the required criteria of homogeneity and showed less than 10% coefficient of variation for stability except negative controls. CONCLUSIONS: Customized external quality controls were developed and qualified for HIV testing reagents used in Korea. Continuous external quality control assessment for HIV tests with controls would be required.
Blotting, Western ; Diagnosis ; HIV Infections ; HIV* ; Humans* ; Indicators and Reagents ; Korea* ; Plasma ; Quality Control* ; Serologic Tests

Background: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. Methods: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan–Meier (KM) method. Results: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010–1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312–7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). Conclusion Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.