Clinical predictors of donor antibody titre and correlation with recipient antibody response in a COVID-19 convalescent plasma clinical trial.

BACKGROUND: Convalescent plasma therapy for COVID-19 relies on transfer of anti-viral antibody from donors to recipients via plasma transfusion. The relationship between clinical characteristics and antibody response to COVID-19 is not well defined. We investigated predictors of convalescent antibody production and quantified recipient antibody response in a convalescent plasma therapy clinical trial. METHODS: Multivariable analysis of clinical and serological parameters in 103 confirmed COVID-19 convalescent plasma donors 28 days or more following symptom resolution was performed. Mixed-effects regression models with piecewise linear trends were used to characterize serial antibody responses in 10 convalescent plasma recipients with severe COVID-19. RESULTS: Donor antibody titres ranged from 0 to 1 : 3892 (anti-receptor binding domain (RBD)) and 0 to 1 : 3289 (anti-spike). Higher anti-RBD and anti-spike titres were associated with increased age, hospitalization for COVID-19, fever and absence of myalgia (all P < 0.05). Fatigue was significantly associated with anti-RBD (P = 0.03). In pairwise comparison amongst ABO blood types, AB donors had higher anti-RBD and anti-spike than O donors (P < 0.05). No toxicity was associated with plasma transfusion. Non-ECMO recipient anti-RBD antibody titre increased on average 31% per day during the first three days post-transfusion (P = 0.01) and anti-spike antibody titre by 40.3% (P = 0.02). CONCLUSION: Advanced age, fever, absence of myalgia, fatigue, blood type and hospitalization were associated with higher convalescent antibody titre to COVID-19. Despite variability in donor titre, 80% of convalescent plasma recipients showed significant increase in antibody levels post-transfusion. A more complete understanding of the dose-response effect of plasma transfusion amongst COVID-19-infected patients is needed.

[Minimally invasive surgery--choledocholithiasis: therapeutic splitting]. / Minimal invasive Chirurgie--Choledocholithiasis: Therapeutisches Splitting.

Patients with cholecysto- and choledocholithiasis may benefit from the advantages of laparoscopic cholecystectomy by intraoperative common bile duct exploration or preoperative endoscopic papillotomy (EPT) with stone removal. We performed therapeutic splitting in 94 patients. Morbidity was 4.2% and mortality was zero. A follow up study of 50 patients shows residual stones in 2% and papillary stenosis in 2%. We believe our results, supported by data on EPT in the literature, show that two-stage endoscopic stone removal prior to laparoscopic cholecystectomy is a safe and effective method for treating cholecystolithiasis combined with choledocholithiasis.

Randomized comparison of fluorouracil and leucovorin therapy versus fluorouracil, leucovorin, and cisplatin therapy in patients with advanced colorectal cancer.

BACKGROUND: Because of experimental and preliminary clinical evidence that additional modulation of the biochemical pharmacology and cytotoxicity of 5-fluorouracil (5-FU) and leucovorin (LV) may be possible by combination of these agents with cisplatin (CDDP), the authors undertook a prospective randomized trial in patients with colorectal cancer. METHODS: Between 1989 and 1992, 138 patients with advanced measurable colorectal cancer previously unexposed to chemotherapy were randomly assigned to treatment with either 5-FU (425 mg/m2) and LV (20 mg/m2) for 5 days, or the combination of 5-FU and LV in the same daily dose plus cisplatin (20 mg/m2), each drug given for 4 consecutive days. In both treatment arms, courses were administered every 28 days, if toxicity allowed, for a total of 6 months or until evidence of tumor progression. RESULTS: The overall responses (complete and partial response) were 19% and 28% for the 5-FU/LV and the 5-FU/LV/CDDP treatment arms, respectively. Although the three-drug combination appeared superior to 5-FU/LV for time to progression or death (8.5 versus 5.2 months; P = 0.042), there was no evidence that the adoption of cisplatin will translate into a definite survival advantage. A comparative analysis of the toxicities experienced by the patients in the two treatment groups showed a comparable rate, although severe side effects (P < 0.05), specifically stomatitis (P = 0.013), were noticed more frequently in patients treated with 5-FU/LV for 5 days. CONCLUSIONS: These results suggest that the therapeutic index of 5-FU/LV in metastatic colorectal cancer may be improved with the addition of cisplatin. However, the somewhat better therapeutic activity and lower incidence of severe gastrointestinal side effects have to be weighed against additional pharmaceutical charges and the need for a more intense antiemetic regimen.