Comparison of autosurge versus surge protocols for discontinuous-flow centrifugation plateletapheresis

Autosurge is a new, highly automated protocol for collecting platelets by centrifugation plateletapheresis. It was developed to allow optimal cell collections with less operator effort than was required with the earlier, standard Surge protocol. The authors compared the cellular content of 201 platelet concentrates prepared by Surge with that of 120 concentrates prepared by Autosurge by the same group of operators, using the same cell separator. Platelet yields were similar (p = 0.775) for both protocols (mean X 10(-11) were 3.54 and 3.57 for Surge and Autosurge, respectively) and when subdivided according to preapheresis donor blood platelet counts, hematocrits, and leukocyte counts. Although platelet yields were comparable in concentrates prepared by either protocol, high donor hematocrit had less adverse effect on platelet yield when the Autosurge protocol was used. The composition of concentrates differed between protocols in that leukocytes contamination was significantly less (p less than 0.001) in units collected by Autosurge (3.4 X 10(8)) than in those collected by Surge (5.8 X 10(8)). Operator involvement can be less intense with Autosurge because the protocol includes automatic adjustment of cell separator settings for optimal plateletapheresis. The results of the direct comparison study were confirmed by data from 509 additional plateletapheresis procedures performed during routine blood center operation. Autosurge should replace Surge because the former easily produces platelet concentrates that contain fewer leukocytes without compromising platelet yields.     

Transfusion-transmitted babesiosis: a case report from a new endemic area

The seventh documented case of babesiosis transmitted by transfusion is reported. Both the donor and the recipient are residents of Connecticut, where the presence of endemic babesiosis has only recently been established. As the range of Babesia microti, and its vector the Ixodes dammini tick, continues to expand, clinicians and blood bank directors should be aware that cases of transfusion-transmitted babesiosis may occur in newly endemic areas.     

Impact of Age and Basic Heart Rate on Heart Rate Turbulence in Healthy Persons

Postextrasystolic acceleration of heart rate (HR), known as HR turbulence (HRT) is attenuated in patients with coronary artery disease at increased risk of adverse events. The influence of age and basic HR on HRT have not been evaluated in a large cohort of persons. In 95 healthy individuals, HRT onset (TO) and slope (TS) were calculated from 24-hour ambulatory electrocardiograms, as well as the turbulence timing (TT). Gender specific differences in TO and TS were compared in simple, linear, weighted regression model. The influence of age and the basic HR preceding ventricular premature contractions on HRT were examined. We found that, in men and women, TO decreases as basic HR increases (P < 0.01). In contrast, in men, TS decreased as basic HR increases, whereas in women, basic HR influenced TS only slightly (P < 0.01). A multiple, linear regression model revealed a decrease in HRT with increasing age in men. In conclusion, physiological acceleration of the HR within the first 11 beats after premature ventricular complex (VPC) was observed in >75% of healthy individuals. An accelerating HR preceding the VPC influenced HRT in men. An increasing age was associated with a decrease in HRT in men and a decrease in TO in women. These results illustrate the importance of physiological modulations of HRT when used for risk stratification, especially in older populations.     

Gallium 67 citrate scanning and serum angiotensin converting enzyme levels in sarcoidosis

Gallium 67 citrate scans and serum angiotensin converting enzyme (ACE) levels were obtained in 54 patients with sarcoidosis and analyzed in relation to clinical manifestations. 67Ga scans were abnormal in 97% of patients with clinically active disease (n = 30) and in 71% of patients with inactive disease (n = 24). Serum ACE levels were abnormally high (2 standard deviations above the control mean) in 73% of patients with clinically active disease and in 54% of patients with inactive disease. Serum ACE levels correlated significantly with 67Ga uptake score (r =.436; p less than .005). The frequency of abnormal 67Ga scans and elevated serum ACE levels suggests that inflammatory activity with little or no clinical expression is common in sarcoidosis. Abnormal 67Ga scans were highly sensitive (97%) but had poor specificity (29%) to clinical disease activity. The accuracy of negative prediction of clinical activity by normal scans (87%) was better than the accuracy of positive prediction of clinical activity by abnormal scans (63%). 67Ga scans can be used to support the clinical identification of inactive sarcoidosis.     

Combined surgical and radiologic intervention for complicated cholelithiasis in high-risk patients

Ultrasound-guided surgical cholecystostomy with local infiltration anesthesia was combined with radiologic removal of gallstones in 36 elderly patients with acute calculous gallbladder disease who were considered to be at high risk due to multiple coexisting diseases. At cholecystostomy, the fundus of the gallbladder was sutured to the anterior abdominal wall resulting in a short surgical track to the gallbladder. This permitted early percutaneous stone removal through the cholecystostomy track under fluoroscopic guidance. All gallstones were removed in 31 of 36 patients, for an overall success rate of 86%. The success rate was 97% for gallbladder stones, 86% for cystic duct stones, and 63% for common bile duct stones that were removed by traversing the cystic duct. The treatment in the five patients in whom radiologic stone removal was incomplete or unsuccessful consisted of elective cholecystectomy in three, with common bile duct exploration in two of these; endoscopic sphincterotomy and stone extraction in one; and expectant management in one. There were no deaths or serious complications. This technique has thus proved safe and effective in these 36 high-risk patients.     

Incidence of T Wave Alternation After Acute Myocardial Infarction and Correlation with Other Prognostic Parameters: Results of a Prospective Study

Tachycardia induced alternation of the T wave (TWA) has been associated with arrhythmia morbidity in mixed patient populations. However, less is known concerning the general incidence of TWA and its usefulness in risk stratification early after acute myocardial infarction (MI). TWA was prospectively and systematically assessed in 140 consecutive patients 15 +/- 6 days after acute MI and prior to discharge. Results of TWA measurements were compared to other noninvasive risk markers, LV function, and coronary angiography. Sustained TWA was present at rest or inducible during exercise in 27% of patients. The patient-specific heart rate for the onset of TWA was 98 +/- 9 beats/min. After multivariate analysis, TWA correlated with age (P = 0.02) and LV function (P = 0.002) and occurred more often in patients after nonanterior MI (P = 0.03). Acute results of Holter monitoring, late potentials by signal-averaged ECG, and heart rate variability were unrelated to the TWA status. During follow-up (451 +/- 210 days) two major arrhythmic events occurred. The incidence of TWA early after MI is about 25%. TWA is related to age and LV function but not to other common arrhythmia markers. Although TWA does not appear to be related to excessive cardiac morbidity, evaluation of the prognostic significance of TWA requires further study.     

Evolution of seroprevalence to SARS-CoV-2 in blood donors in Sarajevo Canton,Federation of Bosnia and Herzegovina: Cross-sectional and longitudinal studies

Background

Sarajevo Canton in the Federation of Bosnia and Herzegovina has recorded several waves of high SARS-CoV-2 transmission and has struggled to reach adequate vaccination coverage. We describe the evolution of infection- and vaccine-induced SARS-CoV-2 antibody response and persistence.

Methods

We conducted repeated cross-sectional analyses of blood donors aged 18–65 years in Sarajevo Canton in November–December 2020 and 2021. We analyzed serum samples for anti-nucleocapsid (anti-N) and anti-spike (anti-S) antibodies. To assess immune durability, we conducted longitudinal analyses of seropositive participants at 6 and 12 months.

Results

One thousand fifteen participants were included in Phase 1 (November–December 2020) and 1152 in Phase 2 (November–December 2021). Seroprevalence increased significantly from 19.2% (95% CI: 17.2%–21.4%) in Phase 1 to 91.6% (95% CI: 89.8%–93.1%) in Phase 2. Anti-S IgG titers were significantly higher among vaccinated (58.5%) than unvaccinated infected participants across vaccine products (p < 0.001), though highest among those who received an mRNA vaccine. At 6 months, 78/82 (95.1%) participants maintained anti-spike seropositivity; at 12 months, 58/58 (100.0%) participants were seropositive, and 33 (56.9%) had completed the primary vaccine series within 6 months. Among 11 unvaccinated participants who were not re-infected at 12 months, anti-S IgG declined from median 770.1 (IQR 615.0–1321.7) to 290.8 (IQR 175.7–400.3). Anti-N IgG antibodies waned earlier, from 35.4% seropositive at 6 months to 24.1% at 12 months.

Conclusions

SARS-CoV-2 seroprevalence increased significantly over 12 months from end of 2020 to end of 2021. Although individuals with previous infection may have residual protection, COVID-19 vaccination is vital to strengthening population immunity.