Efficacy of tacrolimus as long-term immunotherapy for neuronal surface antibody-mediated autoimmune encephalitis

Aims: We aimed to verify the efficacy and safety of tacrolimus as long-term immunotherapy for the treatment of neuronal surface antibody-mediated autoimmune encephalitis (AE) during the first attack. Methods: In this retrospective observational cohort study, patients with neuronal surface antibody-mediated AE who experienced the first attack were enrolled. We compared the outcomes of 17 patients who received tacrolimus with those of 47 patients treated without tacrolimus. Patients were assessed at onset and 3, 6, and 12 months, as well as at the last follow-up, by using the modified Rankin scale (mRS) and the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). The efficacy of tacrolimus was also compared in a subgroup of patients with anti-NMDA receptor encephalitis. Results: Among all patients with neuronal surface antibody-mediated AE, those receiving tacrolimus had lower median mRS scores [1 (IQR = 0–1) versus 2 (IQR = 1–3) in controls, p = 0.001)], CASE scores [2 (IQR = 1–3) versus 3 (IQR = 2–7), p = 0.006], and more favorable mRS scores (94.1% versus 68.1%, p = 0.03) at the 3-month follow-up. No difference was found at the last follow-up. There was no significant difference in the occurrence of relapse and adverse events between the two groups (11.8% versus 14.9%, p = 0.75). In the subgroup of patients with anti-NMDA receptor encephalitis, patients treated with tacrolimus had a lower median mRS score at the 3-month follow-up [1 (IQR = 0–2) versus 2 (IQR = 1–3), p = 0.03]; however, no difference in the outcome was detected at the last follow-up. Conclusion: Tacrolimus can be used as long-term immunotherapy in patients with neuronal surface antibody-mediated AE during the first attack. Treatment with tacrolimus appears to accelerate the clinical improvement of neuronal surface antibody-mediated AE.

Immune response to hepatitis B vaccine following complete immunization of children attending two regional hospitals in the Southwest region of Cameroon: a cross sectional study

Background Hepatitis B virus (HBV) infection despite being a vaccine preventable disease remains a global public health problem. In Cameroon, the hepatitis B vaccine was introduced in the expanded program on immunisation in 2005, but there has been limited evaluation of the HBV surface antibody response post vaccination. Objective We investigated the immune response to hepatitis B vaccine in infants who received the DPT-Hep B-Hib vaccine, and we assessed HBsAg carriage in non-responders. We also investigated factors associated with non-response or poor response. Methods Using a hospital based cross sectional design and a structured questionnaire over a four-month period (January to April 2019), we collected data to determine factors associated with hepatitis B surface antibody (anti-HBs) response from infants aged 6 to 9 months attending infant welfare clinics (IWC) at the Buea and Limbe regional hospitals. We collected venous blood and measured anti-HBs titres using a quantitative Foresight® ELISA. We entered and analysed data using EpiData version 3.1 and SPSS version 25 respectively. Results Of the 161 infants enrolled, 159 (98.8%) developed anti-HBs antibodies. Of these 159, 157 (97.5%) and 117 (72.7%) developed ≥ 10.0 mIU/ml (seroprotection) and ≥ 100.0 mIU/ml anti-HBs titres respectively. Being younger (6 months old) was associated with seroprotection (Cramer V = 0.322, p = 0.001). Spearman rho’s relational analysis showed that immunity against HBV reduced as the duration since the last dose increased (r = −0.172; P = 0.029). However, a Firth logistic regression showed no significant association of factors with inadequate immunity. All 12 (7.5%) infants exposed to HBV at birth, received the hepatitis B vaccine at birth, including four who received HBIG, and all were protected. Four infants (2.5%) had anti-HBs titres < 10.0 mIU/mL (non-responders) but had no peculiarity. Conclusion The seroprotective rate following hepatitis B vaccination of infants is high even in exposed infants. Our study suggests that Cameroon’s HBV vaccine in the Expanded Program on Immunisation (EPI) is effective against HBV, although we could not account for the 2.5% non-response rate. Large scale studies are needed to further explore non-response to the vaccine.

Antibody-Dependent Enhancement of SARS-CoV-2 Infection Is Mediated by the IgG Receptors FcγRIIA and FcγRIIIA but Does Not Contribute to Aberrant Cytokine Production by Macrophages

Viruses infect cells mainly via specific receptors at the cell surface. Antibody-dependent enhancement (ADE) of infection is an alternative mechanism of infection for viruses to infect immune cells that is mediated by antibodies and IgG receptors (FcγRs).

The positive rates of hepatitis B surface antibody in youths after booster vaccination: a 4-year follow-up study with large sample

Background: Hepatitis B virus (HBV) infection is still a public issue of the world. Hepatitis B vaccination is widely used as an effective measure to prevent HBV infection. This large-sample study aimed to evaluate the positive rates of hepatitis B surface antibody (anti-HBs) in youths after booster vaccination. Methods: A total of 37,788 participants were divided into two groups according to the baseline levels of anti-HBs before booster vaccination: the negative group (anti-HBs (-)); the positive group (anti-HBs (+)). Participants were tested for anti-HBs levels after receiving a booster vaccine 1 year and 4 years. Results: The positive rates of anti-HBs were 34.50%, 73.8% and 67.32% before booster vaccination at 1 year and 4 years after vaccination, respectively. At four years after the booster vaccination, the positive rates of 13 to 18 years were 47.54%, which was the lowest level among all youths age groups. In the anti-HBs (-) group, the positive conversion rates of anti-HBs were 74.62% at 1 year after receiving a booster vaccine, and 67.66% at 4 years after vaccination. In the anti-HBs (+) group, the positive maintenance rates of anti-HBs were 70.16% after 1 year, and 66.66% after 4 years. Compared with the baseline anti-HBs (+) group, the positive rates of the baseline anti-HBs (-) group were higher at 1 year and 4 years after receiving the booster vaccine. Conclusions: The positive rates of anti-HBs declined over time, especially the positive maintenance rates were the lowest at age of 13 to 18 years.

Viral hepatitis in correctional facilities in the Northern Territory of Australia 2003–2017

Background The demographic of Northern Territory prison population differs than elsewhere in Australia and the prevalence of hepatitis B and hepatitis C may therefore be somewhat different from other jurisdictions. There has been no study which has specifically described the serological results of a large proportion of prisoners in Northern Territory correctional facilities over an extended period of time. Methods This retrospective longitudinal study reviewed serological results and testing rates for hepatitis B, and hepatitis C performed in correctional facilities in the Northern Territory of Australia between July 1st, 2003 and June 30th, 2017. Results The proportion of positive records over 14 years for hepatitis B surface antigen (HBsAg) was 641/12,066 (5.3, 95% CI 4.9–5.7), for hepatitis B core antibody (anti-HBc) 4937/12,138 (40.1, 95%CI 39.8–41.6), for hepatitis B surface antibody (anti-HBs) 6966/13,303 (52.4, 95% CI 51.5–53.2), and for hepatitis C antibody 569/12,153 (4.7, 95% CI 4.3–5.1). The proportion of prisoners tested for hepatitis B and hepatitis C has decreased since 2015, while a high proportion of prisoners remain non-immune to hepatitis B. Conclusion There is a relatively high proportion of positive serological markers of hepatitis B, and a lower proportion of positive hepatitis C serology in the Northern Territory’s correctional facilities compared to overall Australian rates. As the proportion of prisoners tested for hepatitis B and C has decreased recently, and a high proportion of prisoners remain non-immune to hepatitis B, there are opportunities to increase testing and vaccination rates in this population.

Recurrent anti-NMDAR encephalitis during pregnancy combined with two antibodies positive

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is an autoimmune synaptic encephalitis likely mediated by neuronal surface antibody. Clinically, it is characterized by a variety of neurological and psychiatric symptoms, predominantly affecting young women. Recurrent anti-NMDAR cases combined with double-antibody positive during pregnancy have not been reported. We report a 19-year-old pregnant woman with recurrent anti-NMDAR encephalitis and double-antibody positive. Through our case report and a review of the literature, we hope to heighten an awareness of anti-NMDAR encephalitis, particularly in a pregnant setting.

Chemotherapy-Induced Serological Impact in Hepatitis B Surface Antibody Titers in Children with Acute Lymphoblastic Leukemia

Objective In our study, we aimed to assess the differences in antibody titers against hepatitis B virus (HBV) prior and post leukemia therapy in children with acute lymphoblastic leukemia (ALL). Methods Serum hepatitis B surface antibody (anti-HBs) levels of 96 ALL patients were compared before and postcessation of leukemia therapy from patients' medical records. Discussion Fifty-five patients were male (57.2%) and 41 patients were female (42.7%), and the mean age was 6.1 years (range, 1 ± 15years) at the time of diagnosis. Thirty (32.3%) patients were anti-HBs negative, and 66 (68.7%) patients were anti-HBs positive at initial diagnosis. Anti-HBs–positive 66 patients were categorized into two groups, the first group consisted of 28 (42.4%) anti-HBs–negative patients, and the second group consisted of 38 (57.6%) anti-HBs–positive patients after leukemia therapy. On binary logistic regression analysis, lower initial anti-HBs titers were found to be related to anti-HBs negative results post leukemia therapy (relative risk = 3.696, 95% confidence interval: 2.046–6.678; p = 0.001). The area under the curve was 0.849 with 76.1% sensitivity (95% confidence interval: 0.60–0.87; p = 0.001) and 82.6% specificity (95% confidence interval: 0.69–0.91; p = 0.001); the initial anti-HBs titer cut-off value was found 42.9 IU/L. Conclusion Patients with low-serum anti-HBs titers before leukemia therapy were likely to become anti-HBs negative post leukemia therapy. Therefore, it is necessary to evaluate anti-HBs titers after completing immunosuppressive therapy in patients with ALL.

Hepatitis B Virus Vaccination Status and Anti Hepatitis B Surface Antibody Titer among the Health Care Workers of a Hemodialysis Unit

Background: Health care workers are in high risk of getting infected with hepatitis B virus. A large proportion of them do not receive a 3-dose series of hepatitis B vaccination and have anti hepatitis B surface antibody titer <10 mIU/ml. Materials and Methods: Health care workers of the hemodialysis unit were included from March 2019 to March 2020 and were interviewed about hepatitis B vaccination status. Serum samples of the participants were analyzed for anti hepatitis B surface antibody titer. Participants with antibody titer of <10mIU/ml were given a 3-dose series of hepatitis B vaccination and antibody titer was again measured 1-2 months after the last dose. Results: Among 30 participants, 19 (63.3%) had 3-dose series of hepatitis B vaccination, and all of them had anti hepatitis B antibody titer of >10 mIU/ml. Remaining 11 participants (36.7%), with either partial (6) or no hepatitis B vaccination (5), had antibody titer of <10mIU/ml. The mean ranks of antibody titer was significantly associated with the hepatitis B vaccination status (P<0.001). All 11 participants with antibody titer of <10 mIU/ml received a 3-dose series of hepatitis B vaccine and all of them achieved antibody titer >10 mIU/ml. Conclusion: Our study shows that a large proportion of health care workers of hemodialysis unit were either partially or not vaccinated with hepatitis B vaccination and were having anti hepatitis B antibody titer of <10 mIU/ml. However, with complete 3-dose series of hepatitis B vaccination all of them achieved a protective antibody titer of ≥10 mIU/ml.