Leukocytosis and Tobacco Use: An Observational Study of Asymptomatic Leukocytosis.

PURPOSE: This study aimed to characterize the white blood cell differential of tobacco smoking-induced leukocytosis and describe the longitudinal impact of smoking cessation on this peripheral blood abnormality. METHODS: Medical records of patients undergoing evaluation by hematologists for persistent leukocytosis were reviewed. Patients in whom leukocytosis was determined to be secondary to tobacco use after exclusion of other causes were identified. Demographic and laboratory data were collected at time of diagnosis. Patients were longitudinally followed and information regarding smoking cessation and follow-up white blood cell values were recorded. RESULTS: Forty patients were determined to have smoking-induced leukocytosis. The median age was 49.5 years (range: 28-75 years), 24 patients were female, and the mean body mass index (BMI) was 31.5 kg/m2. The mean white blood cell count was 13.3 × 109/L (range: 9.8-20.9 × 109/L); 39 patients had absolute neutrophilia (98%), 21 had lymphocytosis (53%), 20 had monocytosis (50%), and 19 had basophilia (48%). During follow-up, 11 patients either quit (n = 9) or reduced (n = 2) tobacco use. Reduction in tobacco smoking led to a significant decrease in mean white blood cell count (13.2 × 109/L vs 11.1 × 109/L, P = 0.02). The median time to decrease in white blood cell count following reduction in tobacco use was 8 weeks (range: 2-49 weeks). CONCLUSIONS: Tobacco-induced leukocytosis was characterized by a mild elevation in total white blood cell count and was most commonly associated with neutrophilia, lymphocytosis, monocytosis, and basophilia. Cessation of smoking led to improvement in leukocytosis. Tobacco history should be elicited from all patients presenting with leukocytosis to limit unnecessary diagnostic testing, and counseling regarding smoking cessation should be offered.

Clinical characteristics and mortality of patients with hematologic malignancies and COVID-19: a systematic review.

OBJECTIVE: Hematologic cancer patients with Coronavirus Disease 2019 (COVID-19) tend to have a more serious disease course than observed in the general population. Herein, we comprehensively reviewed existing literature and analyzed clinical characteristics and mortality of patients with hematologic malignancies and COVID-19. MATERIALS AND METHODS: Through searching PubMed until June 03, 2020, we identified 16 relevant case studies (33 cases) from a total of 45 studies that have reported on patients with COVID-19 and hematologic malignancies. We investigated the clinical and laboratory characteristics including type of hematologic malignancies, initial symptoms, laboratory findings, and clinical outcomes. Then, we compared those characteristics and outcomes of patients with hematologic malignancies and COVID-19 to the general population infected with COVID-19. RESULTS: The median age was 66-year-old. Chronic lymphocytic leukemia was the most common type of hematologic malignancy (39.4%). Fever was the most common symptom (75.9%). Most patients had normal leukocyte counts (55.6%), lymphocytosis (45.4%), and normal platelet counts (68.8%). In comparison to patients with COVID-19 without underlying hematologic malignancies, dyspnea was more prevalent (45.0 vs. 24.9%, p=0.025). Leukocytosis (38.9 vs. 9.8%, p=0.001), lymphocytosis (45.4 vs. 8.2%, p=0.001), and thrombocytopenia (31.3 vs. 11.4%, p=0.036) were significantly more prevalent and lymphopenia (18.2 vs. 57.4%, p=0.012) less prevalent in patients with hematologic malignancies. There were no clinical and laboratory characteristics predicting mortality in patients with hematologic malignancies. Mortality was much higher in patients with hematologic malignancies compared to those without this condition (40.0 vs. 3.6%, p<0.001). CONCLUSIONS: Co-occurrence of hematologic malignancies and COVID-19 is rare. However, due to the high mortality rate from COVID-19 in this vulnerable population, further investigation on tailored treatment and management is required.

[Characterization of B1-cells during experimental leukomogenesis.]

BACKGROUND: Bovine leukemia causes a significant polyclonal expansion of CD5+, IgM+ B lymphocytes, known as persistent lymphocytosis (PL), in approximately 30% of infected cattle. However, it is not yet clear what happens to this subpopulation of B cells in the early period of infection of animals. PURPOSE: Quantitative characterization of IgM+ and CD5+ B cells during the immune response, which can provide important information on the mechanisms of lymphocyte priming in BLV infection. MATERIAL AND METHODS: The experiment used BLV-negative calves of black-motley breed at the age of 8 months (n = 11). Animals (n = 8) were intravenously injected with blood of a BLV-positive cow. Control calves (n = 3) were injected with saline. Studies were performed before and after infection on days 5, 7, 14, 21, 28 and 65 of the immune response. The determination of the number of B-lymphocytes in the blood was carried out by the method of immunoperoxidase staining based on monoclonal antibodies to IgM, CD5. RESULTS: As a result of the studies, it was found that the level of CD5+ B cells increases on the 14th day of the primary immune response, characterized by polyclonal proliferation of CD5+ B cells, which are the primary target for BLV. Our research data confirm that in the lymphocytes of experimentally infected cattle, surface aggregation of IgM and CD5 molecules on B-lymphocytes is absent. DISCUSSION: It is known that the wave-like nature of IgM synthesis, which was shown in previous studies, depends on a subpopulation of B1 cells. After 7 days of the immune response, IgM+ and CD5+ cells do not correlate, which shows their functional difference. The increase in CD5+ cells is probably not associated with B cells, but with T cells differentiating under the influence of the virus. CONCLUSIONS: A subset of B1 cells is the primary target of cattle leukemia virus. The 65th day of the immune response is characterized by the expansion of IgM+ B cells, a decrease in the number of CD5+ cells and a uniform distribution of receptors around the perimeter of the cells.

Crystalglobulin-associated nephropathy presenting as MGRS in a case of monoclonal B-cell lymphocytosis: a case report.

BACKGROUND: Crystalglobulin-associated nephropathy (CAN), a rare subtype of monoclonal gammopathy, usually associated with multiple myeloma and occasionally monoclonal gammopathy of uncertain significance (MGUS), is characterized by occluding monoclonal pseudothrombi within renal glomerular capillaries and/or interstitial arterioles. Ultrastructurally, these pseudothrombi are unique for having a crystalline substructure. We describe a case of an adult patient with monoclonal B-cell lymphocytosis (MBL) and acute renal failure whose kidney biopsy revealed a rare diagnosis of CAN. CASE PRESENTATION: A 63-year old male presented with a 2-month history of edema, arthralgia and malaise. He had acute kidney injury with hematoproteinuria on urine analysis. Serum and urine protein electrophoresis were both negative. A renal biopsy however revealed features of CAN. Organomegaly, bone pain and lymphadenopathy were absent. A repeat serum electrophoresis was positive for IgA kappa and a free light chain assay showed elevated free kappa light chains. Flow cytometry done subsequently revealed a diagnosis of MBL, chronic lymphocytic leukemia (CLL) type. CONCLUSION: CAN in association with MBL/CLL has not been previously described in literature, and our case highlights yet another instance of monoclonal gammopathy of renal significance (MGRS) where a small B-cell clone resulted in extensive renal pathology without systemic manifestations.

Association of elevated serumfree light chains with chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis.

Chronic lymphocytic leukemia (CLL) and its precursor, monoclonal B-cell lymphocytosis (MBL), are heritable. Serumfree light-chain (sFLC) measures are a prognostic factor for CLL, but their role in susceptibility to CLL is not clear. We investigated differences between sFLC measurements in pre-treatment serum from five groups to inform the association of sFLC with familial and sporadic CLL: (1) familial CLL (n = 154), (2) sporadic CLL (n = 302), (3) familial MBL (n = 87), (4) unaffected first-degree relatives from CLL/MBL families (n = 263), and (5) reference population (n = 15,396). The percent of individuals having elevated monoclonal and polyclonal sFLCs was compared using age-stratified and age- and sex-adjusted logistic regression models. In age groups >50 years, monoclonal sFLC elevations were increased in sporadic and familial CLL cases compared to the reference population (p's < 0.05). However, there were no statistically significant differences in sFLC monoclonal or polyclonal elevations between familial and sporadic CLL cases (p's > 0.05). Unaffected relatives and MBL cases from CLL/MBL families, ages >60 years, showed elevated monoclonal sFLC, compared to the reference population (p's < 0.05). This is the first study to demonstrate monoclonal sFLC elevations in CLL cases compared to controls. Monoclonal sFLC levels may provide additional risk information in relatives of CLL probands.

Establishing Absolute Lymphocyte Count Thresholds for Further Review of Peripheral Blood Lymphocytosis to Judiciously Screen for Monoclonal B-Cell Populations in Older Adults.

OBJECTIVES: Lymphocytosis may represent either a lymphoproliferative disorder (LPD) or a reactive process. The absolute lymphocyte count (ALC) threshold for further evaluation of lymphocytosis is not well established. METHODS: We prospectively performed flow cytometry on blood samples from patients 50 years or older with ALCs of 4.0 × 109 cells/L or greater without a history of an LPD. RESULTS: Monoclonal B-cell populations were found in 34 (19.1%) of 178 cases, with incidence increasing with age. In patients younger than 75 years, no monoclonal B-cell population was identified in patients with ALCs less than 4.4 × 109 cells/L, while such clones were found below and above this threshold in patients 75 years and older. CONCLUSIONS: These findings support a threshold for smear review and flow cytometry no lower than 4.4 × 109 cells/L in patients younger than 75 years and a threshold as low as 4.0 × 109 cells/L in patients 75 years and older.

Novel association of Streptococcus gallolyticus subspecies pasteurianus and hepatocelluar carcinoma: opening new frontiers.

BACKGROUND: Streptococcus gallolyticus subsp. gallolyticus bacteremia is associated with colorectal malignancies. There is limited data regarding the association of Streptococcus gallolyticus subsp. pasteurianus with malignancies. We aimed to study the pattern of isolation of Streptococcus gallolyticus and analysis of risk factors in patients with hepatobiliary diseases. We also planned to evaluate its association with hepatocellular malignancy. METHODS: We analyzed clinical and laboratory data of 68 cases of Streptococcus gallolyticus infections (77 isolates) from January 2013 to December 2017. These included blood (58), ascitic fluid (15), bile (2) and pleural fluid (2). We analyzed the risk factors in patients developing malignancy with Streptococcus gallolyticus infections. RESULTS: Amongst the 68 patients studied, eight (11.76%) had confirmed malignancies, hepatocellular carcinoma (HCC) (5), rectal adenocarcinoma (1), pancreatic carcinoma (1) and uterine tumors (1). Simultaneous isolation of S. gallolyticus subsp. pasteurianus from blood and ascitic fluid in eight patients (11.8%, p = .01) was significantly associated with the occurrence of HCC. Streptococcus gallolyticus infection with HCC was associated with younger age (median 55 years), lymphocytosis and elevated gamma-glutamyl transferase (GGT). CONCLUSIONS: This study provides a novel insight into the association of Streptococcus gallolyticus subspecies pasteurianus with HCC. The isolation of the organism from blood and ascitic fluid should prompt the clinicians to search for evidence of HCC actively.

Low-count monoclonal B-cell lymphocytosis persists after seven years of follow up and is associated with a poorer outcome.

Low-count monoclonal B-cell lymphocytosis is defined by the presence of very low numbers of circulating clonal B cells, usually phenotypically similar to chronic lymphocytic leukemia cells, whose biological and clinical significance remains elusive. Herein, we re-evaluated 65/91 low-count monoclonal B-cell lymphocytosis cases (54 chronic lymphocytic leukemia-like and 11 non-chronic lymphocytic leukemia-like) followed-up for a median of seven years, using high-sensitivity flow cytometry and interphase fluorescence in situ hybridization. Overall, the clone size significantly increased in 69% of low-count monoclonal B-cell lymphocytosis cases, but only one subject progressed to high-count monoclonal B-cell lymphocytosis. In parallel, the frequency of cytogenetic alterations increased over time (32% vs 61% of cases, respectively). The absolute number of the major T-cell and natural killer cell populations also increased, but only among chronic lymphocytic leukemia-like cases with increased clone size vs age- and sex-matched controls. Although progression to chronic lymphocytic leukemia was not observed, the overall survival of low-count monoclonal B-cell lymphocytosis individuals was significantly reduced vs non-monoclonal B-cell lymphocytosis controls (P=0.03) plus the general population from the same region (P≤0.001), particularly among females (P=0.01); infection and cancer were the main causes of death in low-count monoclonal B-cell lymphocytosis. In summary, despite the fact that mid-term progression from low-count monoclonal B-cell lymphocytosis to high-count monoclonal B-cell lymphocytosis and chronic lymphocytic leukemia appears to be unlikely, these clones persist at increased numbers, usually carrying more genetic alterations, and might thus be a marker of an impaired immune system indirectly associated with a poorer outcome, particularly among females.

Reasons for initiation of treatment and predictors of response for patients with Rai stage 0/1 chronic lymphocytic leukemia (CLL) receiving first-line therapy: an analysis of the Connect® CLL cohort study.

A 'watch-and-wait' strategy is recommended for most patients with early-stage chronic lymphocytic leukemia (CLL) prior to treatment initiation. In the Connect® CLL registry, a prospective observational cohort study of 1494 patients treated in 199 US centers, median time to first-line treatment initiation was 3.8, 1.5, and 0.6 years for patients with Rai stage 0, 1, and ≥2, respectively. Only 60% of patients with Rai stage 0/1 underwent FISH/cytogenetic testing prior to initiation of a new line of therapy. Lymphocytosis and lymphadenopathy were the most common reasons for treatment initiation. Lymphocytosis as a reason for treatment initiation was associated with inferior event-free survival at Rai stage 0/1. Short treatment duration was associated with inferior overall survival regardless of Rai stage; sensitivity analyses confirmed the association. The Connect CLL registry provides valuable information on a real-world population of patients with CLL, clarifying both the timing and rationale for initiating therapy.

Usefulness of the lymphocyte positional parameters in the Sysmex XN haematology analyser in lymphoproliferative disorders and mononucleosis syndrome.

INTRODUCTION: The lymphocyte positional parameters included in Sysmex XN have been suggested as useful means to differentiate lymphoproliferative disorders (LPD), mononucleosis syndrome (MNS) and other lymphocytoses. METHODS: We evaluated Sysmex XN analysers, which supply 6 lymphocyte positional parameters that can be measured in the WDF scattergram: LY-X, LY-Y, LY-Z, LY-WX, LY-WY and LY-WZ. RESULTS: We collected 301 samples from normal controls, polyclonal lymphocytosis, MNS and LPD. MNS and monoclonal expansion of T granular lymphocyte (T-GL) diagnostic groups accumulated higher numbers of significant differences in the mean values in comparison with the other groups. We propose a new algorithm that can differentiate T-GL cases from other diagnostic groups with an SE of 67.5%, an SP of 98.2%, a PPV of 87.1% and an NPV of 94.3%. Another algorithm showed its efficiency to differentiate MNS cases from other diagnostic groups with an SE of 63.6%, an SP of 97.5%, a PPV of 70.0% and an NPV of 96.7%. In 38.5% of all cases, the analyser did not generate any morphologic flag. Abnormal results in lymphocyte positional parameters were useful to detect 72.5% of these samples. CONCLUSION: The lymphocyte positional parameters provided by Sysmex XN analysers are useful to differentiate expansions of T-GLs from other LPD and to differentiate MNS cases from other diagnostic groups. In addition, these parameters are very useful for detecting changes in the lymphocytes that make it necessary to review blood smears in samples without morphological flagging.

Monoclonal B-cell lymphocytosis; not the same as B-cell chronic lymphocytic leukaemia.

INTRODUCTION: Depending on the location and the extent of disease, mature B-cell disorders can be divided into benign monoclonal B-cell lymphocytosis (MBL), chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma (SLL). Whereas SLL is characterised by its location outside the blood stream, MBL is distinguished from CLL by a monoclonal B-cell count below 5 × 109/l. Due to its low tendency to transform into CLL, correct diagnosis of MBL is essential. We hypothesised that this might not always be the case. METHODS: This study includes data on monoclonal B-lymphocyte count based on diagnostic flow cytometry from patients diagnosed in the period from 1 January 2011 to 31 December 2016 at the Department of Haematology, Aarhus University Hospital, Denmark. A total of 69 patients had less than 5 × 109/l monoclonal B-cells with a CLL-like immunophenotype in peripheral blood. All cases were classified based on the 2008 WHO criteria and evaluated according to the clinical diagnosis of CLL, MBL or SLL in the medical records. A total of 24 of the 69 patients were classified as MBL. RESULTS: In the study cohort, 12 (50%) patients classified as MBL were diagnosed accurately with MBL, whereas nine (38%) were diagnosed with CLL. CONCLUSIONS: The findings of this study indicate that a sizeable fraction of MBL patients are diagnosed inaccurately with CLL, even after the introduction of the MBL diagnosis. FUNDING: The Danish Cancer Society. TRIAL REGISTRATION: not relevant.