Prognostic value of hyperlactatemia and lactate clearance in septic patients with hematological malignancies.

BACKGROUND: The coexistence of sepsis and hematological malignancies increases patient vulnerability, revealing the need for precise prognostic markers. This study explores the prognostic significance of lactate levels and clearance in septic patients with hematological malignancies. MATERIALS AND METHODS: A retrospective cohort study from January 2016 to December 2019 in a tertiary hematological intensive care unit (ICU) included 167 adults with hematological malignancies and sepsis. The relationship between lactate levels, hyperlactatemia, lactate clearance, and ICU outcomes was investigated. ICU survivors and non-survivors were compared to identify the factors affecting ICU mortality. RESULTS: Patients were primarily with lymphoma and acute leukemia (66%) and had frequent hyperlactatemia (64%) on ICU admission. ICU non-survivors demonstrated higher lactate levels and hyperlactatemia frequency at various time points (0, 6, and 12 h) than survivors. Lactate clearance and liver function tests did not differ significantly between the two groups. Invasive mechanical ventilation [OR (95% confidence interval-CI): 20.4 (2.4-79.8), p < 0.01], requirement of vasopressors [OR (95% CI): 5.6 (1.3-24.5), p < 0.01], lactate level at the 6th hour [OR (95% CI): 1.51 (1.1-2.07), p = 0.01], and APACHE II score (OR (95% CI): 1.16 (1.01-1.34), p = 0.05) were independent risk factors for ICU mortality. The Area Under the Curve for APACHE II score and lactate level at the 6th hour were 0.774 (95% CI: 0.682-0.866) and 0.703 (95% CI: 0.602-0.804), respectively. CONCLUSION: While elevated lactate levels correlate with mortality rate and lactate level at the 6th hour is an independent risk factor for mortality, the absence of a significant difference in lactate clearance challenges traditional assumptions. These results question the commonly accepted perspective regarding lactate dynamics in sepsis among individuals with hematological malignancies. ORAL PRESENTATION: Inci K, et al. "Hyperlactatemia, lactate clearance and outcome in critically ill patients with hematological malignancies," 22nd international intensive care symposium, 2019.

Infections in hematopoietic stem cell transplant patients admitted to Hematology intensive care unit: a single-center study.

OBJECTIVE: The aim of this study was to investigate the data of HSCT patients who were admitted to our Hematology ICU due to infections or infectious complications. MATERIALS AND METHODS: HSCT patients who were admitted to our Hematology ICU between 01 January 2014 and 01 September 2017 were analyzed retrospectively. RESULTS: 62 HSCT patients were included in this study. The median age was 55.5 years and 58% of the patients were allogeneic HSCT patients. Major underlying hematologic disorders were multiple myeloma (29%) and lymphoma (27.4%). The most common reasons for ICU admission were sepsis/septic shock (61.3%) and acute respiratory failure (54.8%). Overall ICU mortality rate was 45.2%. However, a lot of factors were related with ICU mortality of HSCT patients in univariate analysis, only APACHE II score was found to be an independent risk factor for ICU mortality. While there was infection in 58 patients at ICU admission, new infections developed in 38 patients during ICU stay. The most common new infection was pneumonia/VAP, while the most frequently isolated bacteria were Acinetobacter baumannii. Length of ICU stay, sepsis/septic shock as a reason for ICU admission and the presence of urinary catheter at ICU admission were determined factors for ICU-acquired infections. There was no difference between autologous and allogeneic stem cell transplant patients in terms of ICU morbidities and mortality. However, pneumonia/VAP developed in the ICU was higher in autologous HSCT patients, while bloodstream/catheter-related bloodstream infection was higher in allogeneic HSCT patients. CONCLUSION: It was concluded that early or late post-HSCT infections and related complications (sepsis, organ failure, etc.) constituted a major part of the reasons for ICU admission, ICU mortality and ICU morbidities.

Monoclonal B-cell lymphocytosis in blood donors in Turkey.

OBJECTIVES: Monoclonal B-cell lymphocytosis (MBL) is a precursor state of chronic lymphocytic leukemia (CLL) with peripheral lymphocytosis below 5 × 109/l. The diagnostic criteria exclude the presence of lymphadenopathy, organomegaly, infections, autoimmune diseases or any sign of a lymphoproliferative disorder. This prospective study was designed in order to evaluate the frequency of MBL in blood donors in Turkey. METHODS: The diagnosis of MBL was identified by flow cytometry method based on the International Familial CLL Consortium Report. A total of 999 volunteers [median age 34 (18-78) years; male/female: 705/294] were included in the study. RESULTS: Monoclonal B-cell lymphocytosis was demonstrated in 18 cases (1.8%). A total of 16 cases (1.6%) was evaluated as CLL-like MBL, while 2 (0.2%) had a non-CLL-like phenotype. The subjects were divided into three groups according to age, as <40 years, 40-60 years and >60 years. The prevalence of MBL was 1.1% below 40 years, 0.6% between 40 and 60 years and 0.1% in cases over 60 years, without statistical significance (p > 0.05). DISCUSSION: The sensitivity of the flow cytometry method is essential and may be responsible for the variations in the prevalence of MBL in different populations which can also be attributed to study design, higher detection rates in the elderly and families with genetic predisposition to CLL. CONCLUSION: Large population-based studies and standardized laboratory methods are needed to determine the potential risk factors of progression to CLL, including molecular markers and genetic profile.