• Communications for Statistical Applications and Methods
• /
• 제8권3호
• /
• pp.815-822
• /
• 2001

The aim of this study is to estimate the seroconversion date of the human immunodeficiency virus(HIV) infection for the HIV infected patients in Korea. Data are collected from two cohorts. The first cohort is a group of "seroprevalent" patients who were seropositive and AIDS-free at entry. The other is a group of "seroincident" patients who were initially seronegative but later converted to HIV antibody-positive. The seroconversion dates of the seroincident cohort are available while those of the seroprevalent cohort are not. Estimation of seroconversion date is important because it can be used to calculate the incubation period of AIDS which is defined as the elapsed time between the HIV infection and the development of AIDS. In this paper, a Weibull regression model Is fitted for the seroincident cohort using information about the elapsed time since seroconversion and the CD4$^{+}$ cell count.The seroconversion dates for the seroprevalent cohort are imputed on the basis of the marker of maturity of HIV infection percent of CD4$^{+}$cell count.unt.

• 핵의학기술
• /
• 제12권1호
• /
• pp.78-81
• /
• 2008

목적: 본 연구의 목적은 치료제를 복용하는 만성 B형간염환자의 혈청에서 seroconversion되는 과정 중에 불안정하게 나타나는 HBeAg과 HBeAb 사례를 연구하여, 검사자가 검사결과에 대한 정확한 이해를 하는데 도움을 주고자 하는 것이다. 방법: 만성 B형간염 환자로 진단을 받고 치료제를 복용하고 HBeAg 검사와 HBeAb검사를 시행한 3명을 대상으로 하였다. HBeAg과 HBeAb검사는 Radioimmunoassay법과 Immunoradiometric assay법으로 실시되었다. 결과: HBeAg이 음성화되는 과정에서 결과가 양성에서 음성으로, 다시 양성으로 불안정한 결과를 보였다. HBeAb가 양성화되는 과정에서 결과가 음성에서 양성으로, 다시 음성으로 변하는 불안정한 결과를 보였다. 결론: 이번 사례는 seroconversion 유도를 위해 약물치료중인 만성 B형간염 환자에서 볼 수 있는 불안정한 HBeAg과 HBeAb 혈액 결과이다. 불안정한 HBeAg과 HBeAb 검사 결과를 통하여 검사자는 환자가 바이러스 치료제를 복용하여 seroconversion되는 과정 중에 있을 수 있다는 것과 불안정한 결과는 치료제에 의해 일어나는 자연스러운 현상임을 알 수 있다.

• Clinical and Experimental Vaccine Research
• /
• 제12권1호
• /
• pp.13-24
• /
• 2023

This systematic and meta-analysis aims to evaluate humoral and cellular responses to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine among kidney transplant recipients (KTRs). We conducted a systematic literature search across databases to evaluate seroconversion and cellular response rates in KTRs receiving SARS-CoV-2 vaccines. We extracted studies that assessed seroconversion rates described as the presence of antibody de novo positivity in KTRs following SARS-CoV-2 vaccination published up to January 23rd, 2022. We also performed meta-regression based on immunosuppression therapy used. A total of 44 studies involving 5,892 KTRs were included in this meta-analysis. The overall seroconversion rate following complete dose of vaccines was 39.2% (95% confidence interval [CI], 33.3%-45.3%) and cellular response rate was 41.6% (95% CI, 30.0%-53.6%). Meta-regression revealed that low antibody response rate was significantly associated with the high prevalence of mycophenolate mofetil/mycophenolic acid (p=0.04), belatacept (p=0.02), and antiCD25 induction therapy uses (p=0.04). Conversely, tacrolimus use was associated with higher antibody response (p=0.01). This meta-analysis suggests that postvaccination seroconversion and cellular response rates in KTRs are still low. And seroconversion rate was correlated with the type of immunosuppressive agent and induction therapy used. Additional doses of the SARS-CoV-2 vaccine for this population using a different type of vaccine are considered.

• 대한한의학회지
• /
• 제27권4호
• /
• pp.209-214
• /
• 2006

Objective : Report on a hepatitis B patient with abnormal AST/ALT, HBeAg(+), and habitual diarrhea stemming from irritable colon. Methods : Lab-evaluation of intervals of herb medicine treatment for a patient with hepatitis B with HBeAg and irritable colon. Result & Conclusion : AST/ALT level was normalized and did not rise again. Seroconversion to HBeAb repeatedly appeared just druing the time of the treatment, but typically repeated seroconversion between treatment period and no treatment period confirmed that the treatment was effective for the immune system against hepatitis B. The exact mechanism is not clear but the result provides an indication that oriental herbal medicine has potential capacity to treat liver diseases.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제16권2호
• /
• pp.80-88
• /
• 2013

Purpose: To identify the predictive factors of long-term therapeutic response or resistance to lamivudine treatment in children and adolescents with chronic hepatitis B. Methods: Eighty one children and adolescents with chronic hepatitis B were included, who received lamivudine treatment for at least 6 months. Their condition was monitored for at least 12 months (12-88 months) thereafter. Twenty one (25.9%) were preschool children ($age{\leq}6$). For patients who had developed HBeAg seroconversion or breakthrough, univariate and multivariate analyses were used to identify the effects of age, gender, pretreatment alanine aminotransferase (ALT) and hepatitis B virus DNA levels. Results: HBeAg seroconversion occurred in 49 (60.5%) of the 81 patients after the initiation of the lamivudine therapy. In 65 patients whom were monitored for over 24 months, the seroconversion rate was significantly higher in younger patients (p=0.040), especially in those patients of preschool age ($age{\leq}6$, p=0.031). The seroconversion rate was significantly higher in higher pretreatment ALT (p=0.003). The breakthrough occurred in 21 (25.9%) of the 81. The breakthrough rate was lower in younger aged patients ($age{\leq}6$), and with higher pretreatment ALT levels, but no significant difference. Conclusion: Younger age is a good predictor of HBeAg seroconversion in children with long-term lamivudine treatment as well as high pretreatment ALT levels.

• Journal of Korean Biological Nursing Science
• /
• 제16권1호
• /
• pp.26-32
• /
• 2014

Purpose: Needlestick injuries (NSI) is the most frequent occupational hazard for healthcare personnel (HCP), and immediate report and adequate post-exposure prophylaxis (PEP) is essential in preventing occupational transmission of blood-borne pathogens. Methods: From June 2010 to October 2010, 544 NSI were reported through websites from 21 general hospitals in Korea. Among those, 499 cases of NSI were analyzed to identify the rate of follow-up treatment completion and for seroconversion. Results: 88.2% of the cases were completed with follow-up treatment, 8.8% of the NSI were not completed with follow-up treatment, and 5 cases were unavailable to trace. 4.2% cases of NSI required a hepatitis B vaccination concurrent with hepatitis B immunoglobulin. 41.1% of the cases and 31.1% of the cases needed to be tested for anti HCV and anti HIV, respectively. Prophylaxis medication for HIV was prescribed in 3 cases, and all cases completed required 1 month of medication. There was 1 case (0.2%) of seroconversion to HCV. Conclusion: The PEP completion rate was not satisfactory, and the importance of completion of PEP treatment should be emphasized through education and counseling. Also, a careful risk assessment is needed for HCP who are exposed to HCV or HIV.

• Clinical and Experimental Pediatrics
• /
• 제50권9호
• /
• pp.823-834
• /
• 2007

Interferon (IFN) alpha has been the first line therapy of chronic hepatitis B in children, but HBeAg seroconversion occurred in 26% of treated children compared to 11% of controls in multinational randomized controlled study. Recently, lamivudine was shown to be a potent inhibitor of Hepatitis B virus (HBV) reproduction both in HBeAg positive and in HBeAg negative (the pre-core mutant form) chronic hepatitis in randomized studies worldwide. Lamivudine therapy led to considerable improvement in the seroconversion rate of HBeAg in children with chronic hepatitis B, though long-term therapy resulted in the expansion of lamivudine-resistant mutant viruses. Combination therapy with lamivudine plus alpha-IFN does not seem to improve HBe Ag seroconversion. Above all, the most effective way to prevent hepatitis B is universal HBV vaccination.

• 대한바이러스학회지
• /
• 제30권1호
• /
• pp.11-18
• /
• 2000

Since $Hantavax^{TM}$, formalin inactivated Hantaan virus vaccine (10,240 ELISA units/ml), has been developed in 1990 to prevent against haemorrhagic fever with renal syndrome (HFRS) caused by Hantaan or Seoul virus, it has been commercially available in Korea. Twenty-one healthy people were booster shot once and twice after primary basic vaccination with $Hantavax^{TM}$. Seroconversion rates were measured by immunofluorescent antibody technique (IFAT), enzyme-linked immunosorbent assay (ELISA), high density composite particle agglutination (HDPA), and plaque reduction neutralization test (PRNT). Seroconversion rates of 21 vaccinees at one year after primary basic vaccination were 52.3%, 95.2%, 0.0%, 47.6%, and 28.6%, and 13 vaccinees at one month after 1st booster vaccination were 100%, 100%, 30.7%, 100% and 100% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates declined slightly by twenty months, and they were 84.6%, 92.3%, 0.0%, 84.6% and 69.2% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates of 9 vaccinees at three months after 2nd booster vaccination were 100%, 100%, 0.0%, 100%, and 88.9%, and 16 vaccinees at one year after the 2nd booster vaccination were 87.5%, 93.8%, 0.0%, 87.5% and 81.3% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Based on the above result $Hantavax^{TM}$ has proved a vigorous anamnestic response after the 1st and the 2nd booster vaccination and has persisted higher fluorescence, agglutination and neutralizing antibody titers in vaccinees.

• Clinical and Experimental Vaccine Research
• /
• 제12권2호
• /
• pp.107-115
• /
• 2023

Purpose: The present study aimed to study the immunogenicity of the ChAdOx1 nCoV-19 vaccine in patients with hematologic malignancies. Materials and Methods: This prospective cohort study of hematology patients aimed to evaluate their antibody levels against the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and seroconversion rates following two doses of the ChAdOx1 nCoV-19 vaccine. Between June and July 2021, we enrolled 61 patients and included 44 patients in our analysis. Antibody levels were assessed 8 and 4 weeks after the first and second injections, respectively, and compared with those of a healthy group. Results: Eight weeks after the first dose, the geometric mean antibody level was 1.02 binding antibody units (BAU)/mL in the patient group and 37.91 BAU/mL in the healthy volunteer group (p<0.01). Four weeks after the second dose, the geometric mean antibody level was 9.44 BAU/mL in patients and 641.6 BAU/mL in healthy volunteers (p<0.01). The seroconversion rates 8 weeks after the first dose were 27.27% and 98.86% in the patient and healthy volunteer groups, respectively (p<0.001). The seroconversion rate 4 weeks after the second dose was 47.73% in patients and 100% in healthy volunteers. Factors leading to lower seroconversion rates were rituximab therapy (p=0.002), steroid therapy (p<0.001), and ongoing chemotherapy (p=0.048). Factors that decreased antibody levels were hematologic cancer (p<0.001), ongoing chemotherapy (p=0.004), rituximab (p<0.001), steroid use (p<0.001), and absolute lymphocyte count <1,000/mm³ (p=0.009). Conclusion: Immune responses were impaired in individuals with hematologic malignancies, particularly patients undergoing ongoing therapy and B-cell-depleting therapy. Additional vaccinations should be considered for these patients, and further investigated.

• 대한한방내과학회지
• /
• 제37권3호
• /
• pp.529-538
• /
• 2016

Objectives: The purpose of this case study is to report the efficacy and safety of treatment with Korean medicine of a patient with HBeAg-positive chronic viral hepatitis B.Methods: The patient took Korean medicine (mainly Injinchunggan-tang-gamibang) from July 20th, 2010, to March 14th, 2016, without any antiviral or interferon therapy. Changes to laboratory records, abdomen ultrasonography, and clinical symptoms were reviewed.Results: The laboratory records showed that AST, ALT, and HBV DNA had decreased to normal ranges, and HBeAg showed seroconversion. Clinical symptoms also improved after taking Korean medicine.Conclusion: The results suggest that treatment with Korean medicine and without antiviral or interferon therapy could be effective for HBeAg-positive chronic hepatitis B.