Harmonizing light transmission aggregometry in the Netherlands by implementation of the SSC-ISTH guideline.

Light transmission aggregometry (LTA) is considered the gold standard method for evaluation of platelet function. However, there are a lot of variation in protocols (pre-analytical procedures and agonist concentrations) and results. The aim of our study was to establish a national LTA protocol, to investigate the effect of standardization and to define national reference values for LTA. The SSC guideline was used as base for a national procedure. Almost all recommendations of the SSC were followed e.g. no adjustment of PRP, citrate concentration of 109 mM, 21 needle gauge, fasting, resting time for whole blood and PRP, centrifugation time, speed and agonists concentrations. LTA of healthy volunteers was measured in a total of 16 hospitals with 5 hospitals before and after standardization. Results of more than 120 healthy volunteers (maximum aggregation %) were collected, with participating laboratories using 4 different analyzers with different reagents. Use of low agonist concentrations showed high variation before and after standardization, with the exception of collagen. For most high agonist concentrations (ADP, collagen, ristocetin, epinephrine and arachidonic acid) variability in healthy subjects decreased after standardization. We can conclude that a standardized Dutch protocol for LTA, based on the SSC guideline, does not result in smaller variability in healthy volunteers for all agonist concentrations.

Impact of dissociation on the effectiveness of psychotherapy for post-traumatic stress disorder: meta-analysis.

BACKGROUND: Many patients with post-traumatic stress disorder (PTSD) experience dissociative symptoms. The question of whether these dissociative symptoms negatively influence the effectiveness of psychotherapy for PTSD is unresolved. AIMS: To determine the influence of dissociative symptoms on psychotherapy outcome in PTSD. METHOD: We conducted a systematic search in Cochrane, Embase, PILOTS, PsycINFO, PubMed and Web of Science for relevant clinical trials. A random-effects meta-analysis examined the impact of dissociation on psychotherapy outcome in PTSD (pre-registered at Prospero CRD42018086575). RESULTS: Twenty-one trials (of which nine were randomised controlled trials) with 1714 patients were included. Pre-treatment dissociation was not related to treatment effectiveness in patients with PTSD (Pearson's correlation coefficient 0.04, 95% CI -0.04 to 0.13). Between-study heterogeneity was high but was not explained by moderators such as trauma focus of the psychotherapy or risk of bias score. There was no indication for publication bias. CONCLUSIONS: We found no evidence that dissociation moderates the effectiveness of psychotherapy for PTSD. The quality of some of the included studies was relatively low, emphasising the need for high-quality clinical trials in patients with PTSD. The results suggest that pre-treatment dissociation does not determine psychotherapy outcome in PTSD.

Improving treatment for patients with childhood abuse related posttraumatic stress disorder (IMPACT study): protocol for a multicenter randomized trial comparing prolonged exposure with intensified prolonged exposure and phase-based treatment.

BACKGROUND: Childhood abuse related posttraumatic stress disorder (CA-PTSD) is associated with a high burden of disease and with treatment response rates that leave room for improvement. One of the treatments for PTSD, prolonged exposure (PE), is effective but has high drop-out rates and remission rates are relatively low. An intensified form of PE (iPE) was associated with good response and low drop-out rates in PTSD and has not yet been tested in a controlled trial in CA-PTSD. Phase-based treatment (PBT), in which PE is preceded by skills training may improve overall outcomes in this population. We will assess the effectiveness and cost-effectiveness of standard PE, iPE and PBT in patients with CA-PTSD. METHODS/DESIGN: Multi-center randomized controlled trial. Treatment conditions are: prolonged exposure (PE; maximum of 16 sessions in 16 weeks); intensified PE (iPE; maximum of 12 sessions in four weeks and two booster sessions); phase-based treatment (PBT; maximum of eight sessions skills training followed by eight sessions PE in 16 weeks). PRIMARY OUTCOME: Clinician-rated PTSD symptom severity. SECONDARY OUTCOMES: loss of PTSD diagnosis, self-reported PTSD symptom severity, comorbid symptom severity and quality of life. Moreover, we will examine cost-effectiveness and moderators and mediators of treatment outcome. TARGET POPULATION: adults with CA-PTSD (N = 150). Assessments in weeks 0, 4, 8, 16, 26 and 52. DISCUSSION: Given that no consensus yet exists about the treatment guidelines for patients with CA-PTSD, the present study may have important implications for the treatment of CA-PTSD. TRAIL REGISTRATION: Registered at C.C.M.O. on Sept 7, 2016 (NL57984.058.16); retrospectively registered at June 21, 2017 at clinicaltrials.gov identifier: NCT03194113 .

Multicenter verification of the Sysmex XN-Series.

INTRODUCTION: Verification of hemocytometry equipment deviates significantly from that of clinical chemistry equipment due to the absence of appropriate control material and the need for fresh material. In practice, verification is limited to comparison with the previously used equipment and determination of reproducibilities. Particularly in multicenter settings, harmonization of results is necessary. If the same equipment is used in several laboratory departments, calibration and uniformity are important issues. METHODS: In this study, seven Sysmex XN hematology modules distributed over three laboratories were evaluated with the same set of samples (n=160). RESULTS: Results of each Sysmex XN hematology module were compared with the results of the Sysmex XE-2100 hematology analyzer using linear regression. Although excellent correlation coefficients were obtained, in many cases the criteria for slope and/or intercept were not met. Therefore, the same data were analyzed with Bland-Altman difference plots with three times the specified CV% of the parameter as limits of agreement. At least 90% of the determinations per parameter and per module must comply with those limits of agreement. Almost all parameters on each module fulfilled these criteria, and only RBC and Ht from respectively two and four XN modules had to be recalibrated. Reproducibility of each parameter was determined 10 times in patient samples with low, normal, and high levels. Reproducibility of all parameters was within the specifications of the manufacturer and the biological variability. CONCLUSION: With this straightforward method, all seven Sysmex XN hematology modules demonstrated uniform results, which were identical to those of the previously used Sysmex XE-2100 hematology analyzer, the performance of which was well known.

Self-esteem treatment in anxiety: A randomized controlled crossover trial of Eye Movement Desensitization and Reprocessing (EMDR) versus Competitive Memory Training (COMET) in patients with anxiety disorders.

BACKGROUND AND PURPOSE: Little is known about treating low self-esteem in anxiety disorders. This study evaluated two treatments targeting different mechanisms: (1) Eye Movement Desensitization and Reprocessing (EMDR), which aims to desensitize negative memory representations that are proposed to maintain low self-esteem; and (2) Competitive Memory Training (COMET), which aims to activate positive representations for enhancing self-esteem. METHODS: A Randomized Controlled Trial (RCT) was used with a crossover design. Group 1 received six sessions EMDR first and then six sessions COMET; group 2 vice versa. Assessments were made at baseline (T0), end of first treatment (T1), and end of second treatment (T2). Main outcome was self-esteem. We included 47 patients and performed Linear Mixed Models. RESULTS: COMET showed more improvements in self-esteem than EMDR: effect-sizes 1.25 versus 0.46 post-treatment. Unexpectedly, when EMDR was given first, subsequent effects of COMET were significantly reduced in comparison to COMET as the first intervention. For EMDR, sequence made no difference. Reductions in anxiety and depression were mediated by better self-esteem. CONCLUSIONS: COMET was associated with significantly greater improvements in self-esteem than EMDR in patients with anxiety disorders. EMDR treatment reduced the effectiveness of subsequent COMET. Improved self-esteem mediated reductions in anxiety and depression symptoms.

Flagging performance of the Sysmex XN2000 haematology analyser.

INTRODUCTION: With the introduction of the Sysmex XN haematology analyser, the white blood cell differentiation channel (WDF) and abnormal cell detection channel (WPC) have been added with algorithms for flagging blasts and abnormal or atypical lymphocytes. METHODS: In this study, 2011 samples were evaluated on a Sysmex XN2000 analyser and microscopically reviewed using a CellaVision DM96 digital microscope. RESULTS: A reference group of apparently healthy blood donors (n = 262) demonstrated in only three samples a positive suspect flag, which could not be confirmed microscopically. Positive WBC suspect flags were demonstrated in 3% of the 2011 samples. From the 55 samples with positive WBC suspect flags, an automatic reflex test was performed within the WPC. The WPC reflex test resulted in 10× Blast?, 15× Abnormal lymph? and 15× Atypical lymph? flags, which could be confirmed microscopically in 33% of these cases. A negative flagging was demonstrated in 15 cases. Microscopic evaluation demonstrated no abnormalities in these 15 cases. However, laboratory technicians also reported the presence of abnormal lymphocytes in 158 samples without an Abnormal lymph? flag. CONCLUSION: In conclusion, the combined use of WDF and WPC resulted in a reduction of approximately 25% of the number blood smears. As a result of the various techniques for light microscopy and haemocytometry, the adequacy of the XN flagging for abnormal and atypical lymphocytes cannot be established with certainty. To improve the quality of the reported results, it is recommended that laboratory technicians incorporate the haemocytometry results and the flagging information in the microscopic slide review.

Pseudothrombocytopenia in a neonate due to mother?

UNLABELLED: Ethylenediaminetetraacetic acid (EDTA)-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a false low platelet count reported by an automated haematology analyzer due to in vitro aggregation of platelets. This aggregation is due to the interaction between antibodies and EDTA-dependent crypt antigens on platelets. We observed a new born child whose mother was diagnosed with transient PTCP due to transplacental transmission of maternal immunoglobulin G antibodies during pregnancy. CONCLUSION: Although maternal-neonatal PTCP is rare, it is important to consider this phenomenon as a cause of trombocytopenia, as it can result in unnecessary diagnostic workup and treatment.

Temporary impairment of reticulocyte haemoglobin content in subjects with community-acquired pneumonia.

INTRODUCTION: In the case of inflammation, imbalance of iron homoeostasis is caused by increased retention of iron within cells of the reticuloendothelial system. Iron-restricted erythropoiesis occurs because of decreased availability of iron for haemoglobin (Hb) synthesis in erythroid progenitor cells. Deviations in reticulocyte haemoglobin (Ret-He) content are investigated together with inflammation markers in subjects with community-acquired pneumonia (CAP). Short-term alterations with regard to Ret-He during and after completing antibiotic treatment are investigated. METHODS: A total of 75 patients, classified into three subgroups with CURB-65 scores of ≤1, 2 and ≥3, participated in the study. RESULTS: Within the three subgroups, Hb results demonstrate a decline from the day of admission until day 4. From day 4, an increase towards higher values is observed at day 14. Within 24 h after admission, Ret-He results are situated within the lower quartile region of the reference range interval. Until day 4 of hospital admission, a steady trend towards a decline of 3-8% is established. During antibiotic treatment, an increase in reticulocyte count occurs from 0.039 ± 0.014 × 10(12) /L at day 4 to 0.057 ± 0.020 × 10(12) /L at day 14 (mean ± SD). Recovery of Hb and Ret-He occurs towards values within the reference range. CONCLUSION: In subjects with CAP, acute inflammation results in impairment of Ret-He at an early stage. After onset of pneumonia, decreased results of Ret-He and Ret-He/RBC-He ratio are demonstrated, reflecting acute erythropoietic dysfunction, which are amongst others caused by functional iron depletion.

Changes in platelet volume, morphology and RNA content in subjects treated with haemodialysis.

During haemodialysis treatment, blood flows from the body to the extracorporeal circuit and vice versa. In this study, pathophysiological defects in platelets indicated by alterations in RNA content and aberrations in platelet volume and morphology are detected before and during haemodialysis treatment. In subjects receiving haemodialysis treatment, qualitative interpretation of platelet characteristics with application of light microscopic evaluation reveals only 19+/-11 % of platelets with appropriate staining density of the granule-containing cytoplasm. On the contrary, a reference group of apparently healthy subjects shows 70+/-12 % platelets with appropriate staining density of the granule-containing cytoplasm. During haemodialysis treatment, mean values for platelet volume, platelet distribution width and platelet large cell ratio demonstrate a tendency to decrease by 10 %, 11 % and 6 %, respectively, from the mean initial value to the value at t = 150 min. Reduction of the platelet volume parameters just mentioned is hypothesized to be due to platelet degranulation as a result of platelet activation.

Psychometric evaluation of the Dutch version of the posttraumatic cognitions inventory (PTCI).

Trauma-related cognitions play an increasingly prominent role in research on trauma and in clinical practice. The present study investigated the psychometric characteristics of the Dutch version of the posttraumatic cognitions inventory (PTCI) and evaluated its potential as an outcome measure. Data were collected from a treatment-seeking sample of trauma victims (n=158) and a college sample (n=178). The PTCI's three-factor structure was retained in both samples. The PTCI demonstrated high internal consistency and two-week test-retest reliability. Convergent validity was evidenced by a pattern of correlations with instruments for trauma-related cognitions, posttraumatic stress disorder, and depressive symptoms that largely met a priori expectations. Reductions in self-reported and clinician-assessed posttraumatic stress disorder symptoms were positively associated with decreased PTCI scores, indicating that the PTCI could assist treatment evaluation. It is concluded that the Dutch version of the PTCI exhibits good psychometric characteristics and has the potential to contribute to trauma-related research.

Deviations in coagulation activation due to treatment with different haemodialysis membranes.

Despite systemic heparinization, extracorporeal circulation will induce activation of blood coagulation. Thrombogenicity is associated with biocompatibility of dialysis membranes. Investigation of procoagulatory and fibrinolytic activity is performed prior to and during treatment with haemodialysis. In this study fluctuations of plasma coagulation factor XII, thrombin antithrombin complexes, prothrombin fragment 1 + 2 and thrombus precursor protein were monitored in 10 subjects during treatment with haemodialysis. Subjects were treated with both polysulphone high-flux dialyser membranes (F-60) and low-flux poly-methyl-methacrylate (PMMA) membranes. Immediately after start of treatment, blood in contact with artificial membrane surfaces resulted in a marked decrease in factor XII activity amounting to a mean reduction of 80% in the case of PMMA and a reduction of 40% in the case of F-60. In due course, a steady, on-going generation of thrombin antithrombin complexes was observed in several subjects, especially after treatment with F-60 membranes, amounting to increases exceeding 100% of initial values. Establishment of fibrinogen, prothrombin fragment 1 + 2 and thrombus precursor protein plasma concentrations yielded enhanced results for PMMA compared with the results for treatment with F-60 dialysis membranes. In order to prevent activation of clotting during several stages of haemodialysis, supplementation of anticoagulant can be established on the basis of analytical results of coagulation parameters.

Monocyte activation in peripheral blood and dialyser eluates: phenotypic profile and cytokine release.

BACKGROUND/AIMS: Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysis (HD)-related morbidity. The present study was designed to investigate HD-induced changes in monocytes, with respect to their phenotypic profile and cytokine release, both in peripheral blood (PB) and dialyser eluates (DE). In addition, the effect of the type of dialyser on monocyte activation was assessed. METHODS: Dialyser elution was performed in 8 patients after 3 h of HD, using cuprammonium (CU) and polysulfon (PS) dialysers in a randomised cross-over design. PB samples and DE were analysed for both the expression of a variety of monocyte cell surface markers (CD62L, CD11b, CD25, HLA-DR, CD64 and CD14) by flow cytometry and IL-1beta levels. Monocytes were identified by dual labelling with antibodies against CD14. RESULTS: In PB, the expression of CD11b increased during HD with both devices, but was more pronounced with CU (CU versus PS: p < 0.05). CD62L decreased during HD, but only significantly for PS (p < 0.02). HLA-DR was downregulated during HD with CU (p = 0.056). The expression of CD64 was higher during HD with CU (p = 0.02). Finally, CD14 increased during HD with both dialysers (p < 0.03). DE yielded a mean cell count of 51 x 10(6) cells. The proportion of monocytes in DE was 3% for CU and 4% for PS. In eluted monocytes, a significant upregulation of CD11b, CD25, and HLA-DR was observed. CD62L was downregulated when compared to PB at t(180) (p < 0.001). In DE, no correlation was found between the type of dialyser and the phenotypic changes. In 10 of 16 DE supernatants, 6 CU and 4 PS, IL-1beta release could be demonstrated, CU yielding significantly more of this cytokine than PS (p = 0.03). CONCLUSIONS: According to both their phenotypic profile and cytokine release, monocytes sticking to the dialyser membrane after HD are considerably more activated than circulating monocytes. Activation of eluted monocytes appeared independent of the type of dialyser, suggesting an effect of mechanical stress rather than bioincompatibility. In contrast, phenotypic activation of peripheral blood monocytes and cytokine release in the DE supernatant were mainly dialyser-dependent.

Reduction of preanalytical errors due to in vitro activation of coagulation.

Statistically significant errors due to activation of coagulation may result from the blood sampling procedure. In order to establish the magnitude of errors, blood sample aliquots were drawn in triplicate from one venipuncture. A procedure is described for discrimination of inappropriate analytical results in 162 subjects. Estimated percentages of insufficient duplicate results amounted to 36% for thrombin-antithrombin complexes, to 5% for prothrombin fragment 1+2, to 2% for fibrinogen degradation products and to 4% for fibrin degradation products. It is concluded that the overall reliability of results for coagulation analytes can be considerably improved by drawing blood samples in triplicate and subsequent rejection of samples with inappropriate reproducibility for thrombin-antithrombin. Routine parameters like prothrombin time or activated partial thromboplastin time in normal conditions are not susceptible for the phenomenon of coagulation activation.

Predictive value of inflammatory and coagulation parameters in the course of severe ulcerative colitis.

Alterations in markers of coagulation have been found in patients with inflammatory bowel disease. Our aim was to study the predictive value of coagulation and inflammatory parameters in the course of severe ulcerative colitis. Twenty-seven patients were included. The disease course was followed for one year. Sensitivity, specificity, negative predictive value, positive predictive value, and likelihood ratio, as well as the clinical predictive value of laboratory variables were calculated. Inflammatory variables, such as ESR, CRP, and leukocyte and platelet count showed poor diagnostic accuracy. Several coagulation parameters, such as fibrinogen and fibrin(ogen) degradation products, were increased in patients with active ulcerative colitis, whereas coagulation factor XIII was decreased. No significant relationship between clinical course and coagulation parameters was demonstrated, though both inflammatory and coagulation parameters were useful in the assessment of disease activity in patients with active ulcerative colitis.

Hemostatic imbalance in active and quiescent ulcerative colitis.

OBJECTIVE: In healthy conditions, factors inducing or inhibiting coagulation and factors inducing or inhibiting fibrinolysis are in balance. In ulcerative colitis, hypercoagulation is presumed, which may explain part of the clinical features of this disease. Therapy strategies affecting hemostasis may improve the course of ulcerative colitis. This study was conducted to evaluate the balance of coagulation and fibrinolysis in the course of treatment of active ulcerative colitis. METHODS: Patients with active ulcerative colitis were studied by serial determination of markers of the coagulation cascade (thrombin-antithrombin complexes and fibrin degradation products [FbDP]) and the fibrinolytic cascade (fibrinogen degradation products [FgDP]). Parameters of inflammation were also measured (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], albumin, platelet count, and fibrinogen). Disease activity was assessed by endoscopic and histopathological scores. Follow-up measurement was performed in the course of treatment at the third or fourth month after baseline. Measurements were compared with healthy controls. RESULTS: Thirty-three patients and 22 healthy controls were included. During active ulcerative colitis, inflammatory parameters (CRP, ESR, platelet count) and hemostatic parameters (thrombin-antithrombin complexes, fibrinogen, FgDP, and FbDP) were elevated in comparison with healthy controls. Albumin was decreased and antithrombin-III remained unchanged. During treatment, disease activity decreased significantly endoscopically and histopathologically (p < 0.001). CRP, ESR, platelet count, and fibrinogen also decreased significantly. The hemostatic balance, expressed as the ratio between the plasmin-dependent generation of FgDP and coagulation-dependent generation of FbDP, increased from 0.69 to 1.12 during treatment, mainly because of a decrease of FbDP. In healthy controls, this ratio was CONCLUSIONS: The coagulation and fibrinolytic cascades were activated in active ulcerative colitis, with a hemostatic imbalance in favor of coagulation. This hypercoagulability persisted in 20% (7/33) of patients with ulcerative colitis in remission. The decrease of FbDP and the increase in the FgDP/FbDP ratio during reconvalescence of ulcerative colitis showed that the coagulation cascade was more activated than the fibrinolytic cascade in active disease.

Activation of coagulation during treatment with haemodialysis.

Generation of factor XII, thrombin antithrombin complexes, prothrombin fragment 1+2 and thrombus precursor protein has been monitored in 16 subjects during haemodialysis. Immediately after starting treatment, contact of blood with the negatively charged surfaces of the polyacrylnitril membrane AN-69 resulted in a 9-45% decrease in factor XII activity. Peak concentrations for thrombin antithrombin complexes (50 to 120 microg/L) were observed 30 min after the start of haemodialysis. Establishment of thrombus precursor protein concentrations yielded steadily increasing results without any tendency to decrease during treatment. Determination of thrombin antithrombin complexes is considered to establish the most sensitive short-term reacting parameter indicating activation of coagulation. A steady generation of fibrin and fibrinogen-fibrin complexes during treatment with haemodialysis is indicated by increasing results for thrombus precursor protein. In order to prevent clotting during haemodialysis, an additional supplementation of anticoagulant is needed.

Hemodialysis-induced degranulation of polymorphonuclear cells: no correlation between membrane markers and degranulation products.

BACKGROUND/AIMS: Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed by measuring degranulation products. However, this process might also be estimated by the assessment of cell surface markers. In this study, the relationship between the expression of PMN degranulation markers (CD63 and CD66b) and the release of degranulation products [myeloperoxidase (MPO) and lactoferrin (LF)] was investigated during clinical HD in order to evaluate cell surface markers as a useful index of PMN degranulation. METHODS: The expression of CD63 and CD66b on PMN and the release of MPO and LF were investigated in 10 chronic HD patients, during both heparin (HDhep) and trisodium citrate anticoagulation (HDcit), in a randomized order. Samples were drawn from both the efferent and afferent lines of the dialyzer at 0, 7.5, and 180 min. RESULTS: During HDhep at first passage, a major increase in MPO (from 158 +/- 32 to 448 +/- 177 microg/l, p = 0.001) and LF (from 134 +/- 52 to 260 +/- 120 microg/l, p = 0.01) was found across the dialyzer, whereas marked changes were not observed during HDcit. The expression of CD63 and CD66b increased across the dialyzer during both anticoagulation modalities, but was only significant in the case of HDhep (CD63: mean fluorescence intensity from 247 +/- 61 to 331 +/- 118, p < 0.01; CD66b: mean fluorescence intensity from 340 +/- 76 to 434 +/- 103, p = 0.01). During HDhep a correlation was noted between the degranulation products and markers of both azurophilic and specific granules (MPO and CD63: r = 0.35; p < 0.01; LF and CD66b: r = 0.39, p < 0.01). Significant differences in the expression of CD63 and CD66b between HDhep and HDcit were not observed. When analyzing the combined data for both HDhep and HDcit, no correlation was observed between degranulation products and markers. CONCLUSION: Our data suggest that the measurements of cell surface markers may not be a reliable indicator of the degree of HD-induced PMN degranulation.

Effects of dialyser and dialysate on the acute phase reaction in clinical bicarbonate dialysis.

BACKGROUND: In chronic haemodialysis (HD), morbidity may result from repetitive induction of the acute phase response, caused by a bioincompatible dialysis membrane and/or contaminated dialysate. In the present study, cytokine release (interleukin-6, IL-6) and subsequent production of acute phase proteins (C-reactive protein, CRP and secretory phospholipase A(2), sPLA(2)) were assessed to investigate whether the HD-induced acute phase reaction depends mainly on the type of membrane or on the sterility of the dialysate. METHODS: In 11 patients, IL-6, CRP and sPLA(2) levels were assessed in blood samples drawn before (t(0)), at the end (t(180)) and 24 h after the start of HD (t(1440)). All patients were dialysed on Cuprammonium (CU) and Polysulphon (PS) dialysers and seven patients underwent an additional HD session on CU plus a dialysate filter (CUf). RESULTS: IL-6 levels were increased significantly at t(180) compared with t(0) (P<0.02) with both CU and CUf. At t(1440), IL-6 levels had returned to baseline. In contrast, marked fluctuations did not occur during HD with PS. At t(180), IL-6 was significantly greater with CU and CUf devices, than with PS (P<0.02). Following HD with CU and CUf, a significant increase in CRP was observed at t(1440), compared with postdialysis values (P

Time dependent increase of differential monocyte count on the Sysmex NE-8000.

During storage of whole blood samples the results of white blood cell counts on a Sysmex NE-8000 Hematology Analyser showed an apparent shift from the granulocytes towards monocytes. The effects of various storage conditions were investigated by incubating blood samples at different temperatures and time intervals. Granulocyte activation and degranulation during storage resulted in a false elevation of the automated monocyte differential counts. The phenomenon occurs at temperatures beyond ambient room temperature.