The dilution evaluation as a corrective measure for interference in the white blood cell scattergram in Beckman Coulter DxH 900.

BACKGROUND: The Beckman Coulter DxH 900 is a haematological analyser capable of counting and sizing blood cells, and obtaining a complete blood cell count (CBC). This analyses different parameters of red blood cells (RBC), platelets and white blood cells/leukocytes. Some automated CBC counters present limitations due to specimen characteristics, abnormal cells or both factors. In the presence of abnormalities, the DxH 900 has a flagging system, warning the laboratory technician that something needs to be verified. In the present work, we evaluated samples from oncologic patients, presenting a population erroneously perceived as being lymphocytes. The most common explanations for this situation are RBC resistant to lysis or serum hyperbilirubinaemia. METHODS: In an attempt to solve and understand what the cause of this problem might be, we diluted our samples (1:3) and analysed the serum total bilirubin. To identify cells' abnormalities, the samples were also analysed by manual DLC counts. During the study, we also checked the different flags presented by the equipment. RESULTS: The results evidenced that the major interference was due to RBC lysis resistance, corresponding to 94.7% of the cases, while hyperbilirubinaemia was only present in 73.4%. Besides, we determined that some samples with normal bilirubin levels also presented interference, suggesting that hyperbilirubinaemia was not the main cause of the error. The most recurrent flag observed was "High event rate". CONCLUSION: The dilution solved all of the observed interferences. The results between diluted and manual counts showed a strong correlation, leading us to introduce dilution in our laboratory routine.

Humoral immunogenicity and tolerability of heterologous ChAd/BNT compared with homologous BNT/BNT and ChAd/ChAd SARS-CoV-2 vaccination in hemodialysis patients : A multicenter prospective observational study.

BACKGROUND: After the reports of severe adverse reactions to the AstraZeneca ChAdOx1-S-nCoV-19 vaccine, patients who had received one dose of ChAdOx1-S-nCoV-19 vaccine were recommended a second dose of Pfizer's BNT162b2 vaccine. In hemodialysis patients, we compared the humoral immunogenicity and tolerability of homologous vaccination with ChAdOx1-nCoV-19/ChAdOx1-nCoV-19 (ChAd/ChAd) and BNT162b2/BNT162b2 (BNT/BNT) with heterologous vaccination of first dose of ChAdOx1-nCoV-19 and a second dose with BNT162b2 (ChAd/BNT). METHODS: In a multicenter prospective observational study, SARS-CoV-2 spike-IgG antibody levels, Nucleocapsid-protein-IgG-antibodies, and vaccine tolerability were assessed 6 weeks after second SARS-CoV-2 vaccination in 137 hemodialysis patients and 24 immunocompetent medical personnel. RESULTS: In COVID-19-naïve hemodialysis patients, significantly higher median SARS-CoV-2-spike IgG levels were found after ChAd/BNT (N = 16) compared to BNT/BNT (N = 100) or ChAd/ChAd (N = 10) (1744 [25th-75th percentile 276-2840] BAU/mL versus 361 [25th-75th percentile 120-936] BAU/mL; p = 0.009; 1744 [25th-75th percentile 276-2840] BAU/mL versus 100 [25th-75th percentile 41-346] BAU/mL; p = 0.017, respectively). Vaccinated, COVID-19-naïve medical personnel had median SARS-CoV-2 spike-IgG levels of 650 (25th-75th percentile 217-1402) BAU/mL and vaccinated hemodialysis patients with prior COVID-19 7047 (25th-75th percentile 685-10,794) BAU/mL (N = 11). In multivariable regression analysis, heterologous vaccination (ChAd/BNT) of COVID-19-naïve hemodialysis patients was independently associated with SARS-CoV-2 spike-IgG levels. The first dose of ChAd and the second dose of BNT after the first vaccination with ChAd (heterologous vaccination, ChAd/BNT) were associated with more frequent but manageable side effects compared with homologous BNT. CONCLUSIONS: Within the limitations of this study, heterologous vaccination with ChAd/BNT appears to induce stronger humoral immunity and more frequent but manageable side effects than homologous vaccination with BNT/BNT or with ChAd/ChAd in COVID-19-naïve hemodialysis patients.

The Perceived Risk of Hospitalization in Primary Health Care - The Importance of Multidimensional Assessment.

Ageing has increased the use of health services, with a corresponding rise in avoidable hospitalizations. We aimed to assess and characterize the perceived risk of hospitalization in primary health care (PHC). 118 individuals aged ≥65 years, PHC patients, were assessed using the Community Risk Assessment Instrument by their General Practitioner, who identified their perceived risk of hospitalization, at one year. The instrument is composed of three domains (mental state, daily living activities (ADLs) state and medical state). Multivariate logistic regression was used to identify the best model to predict the risk of hospitalization. Four models were estimated, one for each domain and one with all the variables of the instrument. 58.5% were identified as being at risk of hospitalization. The best predictive models are those that include functionality assessment variables (ADL model and Community Assessment of Risk Instrument model). The model that includes all the variables of three domains presents the best predictive value. Mobility problems (Odds Ratio (OR) 16.18 [CI: 1.63-160.53]), meal preparation (OR 10.93 [CI: 1.59-75.13]), communication (OR 6.91 [CI: 1.37-34.80]) and palliative care (OR 4.84 [CI: 1.14-20.58]) are the best predictors of hospitalization risk. The use of multidimensional assessment tools can allow the timely identification of people at risk, contributing to a reduction in hospitalizations.

Outcomes of Different Methods for Analysis of Biliary Brush Cytology and of Factors Associated with Positive Diagnosis in an Age-Dependent Retrospective Review.

BACKGROUND AND AIMS: Brush cytology during endoscopic retrograde cholangiopancreatography (ERCP) is the most frequently used strategy for obtaining a tissue sample from an indeterminate biliary stricture. A recent study reported that age is a factor associated with positive yields, but further analysis of how age influences the results was lacking. We aimed to evaluate clinical effectiveness of biliary cytology and prognostic factors for a positive outcome, especially age. METHODS: This study was a single-center, retrospective, clinical study of 77 consecutive patients who underwent brush cytology during ERCP to obtain a diagnosis of an indeterminate biliary stricture. We compared 2 routine cytology techniques: A (smear); B (centrifugation of the cytological material collected and the cut-off brush + cell block when sufficient amount of material was available). The data were collected aiming to compare the accuracy of the different techniques used and the prognostic factors affecting the outcome, with a particular focus on age. The yield for brush cytology was compared with the gold standard defined as either definitive histology or the long-term clinical course. RESULTS: The overall accuracy of the 2 used methods was 75.3%. Sensitivity was 52.5%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 66.1%. Although not statistically significant, there was a trend toward accuracy for method B compared with method A (80.4 vs. 65.4%; p = 0.153). Multiple logistic regression analysis showed that younger age was the only independent prognostic factor associated with a positive diagnosis (OR 0.95; 95% CI 0.90-0.99; p = 0.039). Receiver operating characteristic curves for age yielded an area under the curve value of 68.2%. On the basis of the Youden index, 69 years was found to be the optimal cutoff for age. CONCLUSIONS: In this series, the accuracy of routine biliary brush cytology was not equal for all methods and ages; in particular, younger patients (below 69 years) tended to have a higher probability of a correct diagnosis.

INTRODUÇÃO: a citologia biliar é a técnica mais utilizada durante a CPRE para o diagnóstico de uma estenose indeterminada. Um artigo recente refere a importância da idade como fator preditivo de um resultado positivo, embora sem analisar este dado. Pretendemos avaliar a acuidade da citologia biliar e dos factores associados para a obtenção de um resultado positivo com especial interesse na idade. MÉTODOS: análise retrospectiva de um único centro de 77 doentes consecutivos submetidos, durante CPRE a citologia biliar para esclarecer a etiologia de uma estenose biliar. A análise comparou 2 técnicas de rotina: A (esfregaço); B (centrifugação do material colectado e da escova+cell block quando existia material suficiente). Pretendeu-se comparar a acuidade diagnóstica dos 2 diferentes métodos e dos factores de prognóstico associados ao resultado em especial a idade. A acuidade da citologia foi comparada com o "gold standard" definido como a histologia definitiva ou o curso clínico a longo prazo. RESULTADOS: a acuidade global dos diferentes métodos foi 75.3%. A sensibilidade foi 52.5%, a especificidade foi 100%, VPP foi 100% e o VPN foi 66.1%. Apesar de não ser estatisticamente definitivo existiu maior acuidade do método B, em comparação com o A (80.4 vs. 65.4%; p = 0.153). A análise multivariada por regressão logística mostrou que a menor idade é o único fator de prognóstico independente associado a um resultado positivo (OR: 0.95; 95% CI: 0.90­0.99; p = 0.039). As curvas ROC para a idade apresentaram um valor para a AUC de 68.2%. O índice de Youden, determinou que os 69 anos seriam o "cutoff" ideal para a idade. CONCLUSÕES: nesta população a acuidade de citologia biliar não foi idêntica para todos os métodos e idades; em particular doentes com idade inferior a 69 anos apresentam maior probabilidade de obter um diagnóstico correto.

Outcomes of endoscopic management of primary and refractory postcholecystectomy biliary leaks in a multicentre review of 178 patients.

BACKGROUND: Biliary leaks have been treated with endoscopic management using different techniques with conflicting results. Furthermore the appropriate rescue therapy for refractory leaks has not been established. We evaluated the clinical effectiveness of initial endotherapy for postcholecystectomy biliary leaks using an homogenous approach (sphincterotomy + placement of a 10-French plastic stent) in a large series of patients as well as the optimal and efficacy of rescue endotherapy for refractory biliary leaks. METHODS: This was a multicenter, retrospective study of 178 patients who underwent endoscopic management of postcholecystectomy biliary leaks with a combination of biliary sphincterotomy and the placement of a large-bore (10-French) plastic stent. Data were collected to analyze the clinical outcomes and technical success, efficacy of the rescue endotherapy and the need for surgery, adverse events and prognostic factors for clinical success of endotherapy. RESULTS: Following endotherapy, closure of the leak was accomplished in 162/178 patients (91.0%). The multivariate logistic model showed that the type of leak, namely a high-grade biliary leak, was the only independent prognostic factor associated with treatment failure (OR = 26.78; 95% CI = 6.59-108.83; P < 0.01). The remaining 16 patients were treated with multiple plastic stents (MPSs) with a success rate of 62.5% (10 patients). The use of fewer than 3 plastic stents (P = 0.023) and a high-grade biliary leak (P = 0.034) were shown to be significant predictors of treatment failure with MPSs in refractory bile leaks. The 6 patients in whom the placement of MPSs failed were retreated with a fully cover self-expandable metallic stent (FCSEMS), resulting in closure of the leak in all cases. CONCLUSIONS: Endotherapy of biliary leaks with a combination of biliary sphincterotomy and the placement of a large-bore plastic stent is associated with a high rate of success (90%). However in our series there were several failures using MPSs as a strategy for rescue endotherapy suggesting that refractory biliary leaks should be treated with FCSEMS especially in patients with high-grade leaks.

Chasing the Effects of Pre-Analytical Confounders - A Multicenter Study on CSF-AD Biomarkers.

INTRODUCTION: Core cerebrospinal fluid (CSF) biomarkers - Aß42, Tau, and phosphorylated Tau (pTau) - have been recently incorporated in the revised criteria for Alzheimer's disease (AD). However, their widespread clinical application lacks standardization. Pre-analytical sample handling and storage play an important role in the reliable measurement of these biomarkers across laboratories. AIM: In this study, we aim to surpass the efforts from previous studies, by employing a multicenter approach to assess the impact of less studied CSF pre-analytical confounders in AD-biomarkers quantification. METHODS: Four different centers participated in this study and followed the same established protocol. CSF samples were analyzed for three biomarkers (Aß42, Tau, and pTau) and tested for different spinning conditions [temperature: room temperature (RT) vs. 4°C; speed: 500 vs. 2000 vs. 3000 g], storage volume variations (25, 50, and 75% of tube total volume), as well as freezing-thaw cycles (up to five cycles). The influence of sample routine parameters, inter-center variability, and relative value of each biomarker (reported as normal/abnormal) was analyzed. RESULTS: Centrifugation conditions did not influence biomarkers levels, except for samples with a high CSF total protein content, where either non-centrifugation or centrifugation at RT, compared to 4°C, led to higher Aß42 levels. Reducing CSF storage volume from 75 to 50% of total tube capacity decreased Aß42 concentration (within analytical CV of the assay), whereas no change in Tau or pTau was observed. Moreover, the concentration of Tau and pTau appears to be stable up to five freeze-thaw cycles, whereas Aß42 levels decrease if CSF is freeze-thawed more than three times. CONCLUSION: This systematic study reinforces the need for CSF centrifugation at 4°C prior to storage and highlights the influence of storage conditions in Aß42 levels. This study contributes to the establishment of harmonized standard operating procedures that will help reducing inter-lab variability of CSF-AD biomarkers evaluation.

A non-randomized study in consecutive patients with postcholecystectomy refractory biliary leaks who were managed endoscopically with the use of multiple plastic stents or fully covered self-expandable metal stents (with videos).

BACKGROUND: Endoscopic management of postcholecystectomy biliary leaks is widely accepted as the treatment of choice. However, refractory biliary leaks after a combination of biliary sphincterotomy and the placement of a large-bore (10F) plastic stent can occur, and the optimal rescue endotherapy for this situation is unclear. OBJECTIVE: To compare the clinical effectiveness of the use of a fully covered self-expandable metal stent (FCSEMS) with the placement of multiple plastic stents (MPS) for the treatment of postcholecystectomy refractory biliary leaks. DESIGN: Prospective study. SETTING: Two tertiary-care referral academic centers and one general district hospital. PATIENTS: Forty consecutive patients with refractory biliary leaks who underwent endoscopic management. INTERVENTIONS: Temporary placement of MPS (n = 20) or FCSEMSs (n = 20). MAIN OUTCOME MEASUREMENTS: Clinical outcomes of endotherapy as well as the technical success, adverse events, need for reinterventions, and prognostic factors for clinical success. RESULTS: Endotherapy was possible in all patients. After endotherapy, closure of the leak was accomplished in 13 patients (65%) who received MPS and in 20 patients (100%) who received FCSEMSs (P = .004). The Kaplan-Meier (log-rank) leak-free survival analysis showed a statistically significant difference between the 2 patient populations (χ(2) [1] = 8.30; P < .01) in favor of the FCSEMS group. Use of <3 plastic stents (P = .024), a plastic stent diameter <20F (P = .006), and a high-grade biliary leak (P = .015) were shown to be significant predictors of treatment failure with MPS. The 7 patients in whom placement of MPS failed were retreated with FCSEMSs, resulting in closure of the leaks in all cases. LIMITATIONS: Non-randomized design. CONCLUSION: In our series, the results of the temporary placement of FCSEMSs for postcholecystectomy refractory biliary leaks were superior to those from the use of MPS. A randomized study is needed to confirm our results before further recommendations.

Endoscopic bilio-duodenal bypass: outcomes of primary and revision efficacy of combined metallic stents in malignant duodenal and biliary obstructions.

BACKGROUND: Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients' lives, as well as the need for and efficacy of endoscopic revision, are unclear. AIM: This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients' lives and the need for endoscopic revision. METHODS: This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients' death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency. RESULTS: Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43-198.98; P = 0.025). CONCLUSIONS: Endoscopic bilio-duodenal bypass is clinically effective, and the majority of the patients need no additional intervention until their death. Endoscopic revision is feasible and has a high success rate.

Predictive value of cholangioscopy after endoscopic management of early postcholecystectomy bile duct strictures with an increasing number of plastic stents: a prospective study (with videos).

BACKGROUND: Endotherapy of postcholecystectomy bile duct stricture (PCBS) has been established as an alternative treatment to surgery. Several studies have reported conflicting results regarding the predictors of success or failure of endotherapy. OBJECTIVE: To evaluate the different cholangioscopic appearances of PCBS after endotherapy with an increasing number of plastic stents and the predictive values of these appearances for the outcome. DESIGN: Prospective study with a long-term follow-up. SETTING: Two academic tertiary referral centers. PATIENTS: Twenty consecutive patients with major bile duct injury, with a bile leak, and a PCBS who underwent therapeutic ERCP. INTERVENTIONS: Closure of the leak followed by temporary placement of multiple plastic stents for the treatment of PCBS, followed by cholangioscopy at the end of endotherapy. MAIN OUTCOME MEASUREMENTS: To analyze the predictive value of cholangioscopy, other predictors of stricture recurrence after endotherapy, and long-term clinical success. RESULTS: Closure of the leak was achieved in all patients. The median duration of endotherapy was 12 months (range 7-18 months). After endoscopic stenting, the PCBS was considered to be appropriately dilated in all patients. After endotherapy, 3 different findings were noted on cholangioscopy: (1) no lesion or minor defect (n = 10), (2) minor stricture with a fibrous ring (n = 6), and (3) presence of tissue hyperplasia (n = 4). During follow-up, stricture recurrence developed in 4 of 20 patients. All 4 patients were successfully retreated by an additional period of stenting and remained free of cholestasis after a median follow-up period of 44 months. By Kaplan-Meier (log-rank) and univariate analyses, the cholangioscopic pattern of tissue hyperplasia was significantly associated with stricture recurrence (P < .01). LIMITATIONS: Small sample size. CONCLUSIONS: Endoscopic stenting should be regarded as the primary treatment of choice because of the successful long-term outcome after 1 or more additional periods of treatment. However, the cholangioscopic pattern of tissue hyperplasia at the time of stent removal is a strong predictor of stricture recurrence, and this observation may lead to an additional period of endotherapy or other treatment modalities.