Creatinine is a parameter that is required to monitor renal function and is important to follow in patients under treatment with potentially toxic renal drugs, such as the anti-HIV drug Tenofovir. A point of care instrument to measure creatinine would be useful for patients monitoring in resource-limited settings, where more instruments that are sophisticated are not available. The StatSensor Xpress Creatinine (Nova Biomedical Cooperation, Waltham, MA, USA) point of care analyzer was evaluated for its diagnostic performance in indicating drug therapy change. Creatinine was measured in parallel using the Nova StatSensor Xpress Creatinine analyzer and the Vitros 5,1FS (Ortho Clinical Diagnostics, Inc, Rochester, USA), which served as reference standard. The precision (i.e., repeatability and reproducibility) and accuracy of the StatSensor Xpress Creatinine analyzer were calculated using a panel of specimens with normal, low pathological and high pathological values. Two different Nova StatSensor Xpress Creatinine analyzers were used for the assessment of accuracy using repeated measurements. The coefficient of variation of the StatSensor Xpress Creatinine analyzers ranged from 2.3 to 5.9% for repeatability and from 4.2 to 9.0% for between-run reproducibility. The concordance correlation agreement was good except for high values (>600 µmol/L). The Bland-Altman analysis in high pathological specimens suggests that the Nova StatSensor Xpress Creatinine test tends to underestimate high creatinine values (i.e., >600 µmol/L). The Nova StatSensor Xpress Creatinine analyzers showed acceptable to good results in terms of repeatability, inter-device reproducibility and between-run reproducibility over time using quality control reagents. The analyzer was found sufficiently accurate for detecting pathological values in patients (age >10 year) and can be used with a moderate risk of misclassification.

Unrecognized anticoagulant-induced platelet (PLT) aggregation, leading to pseudothrombocytopenia and concomitant pseudoleukocytosis, can have serious clinical consequences. It can be readily recognized by inspecting conventional blood smears or the white blood cell histograms generated by modern blood cell counters. Blood specimens from twenty patients with known EDTA-induced platelet aggregation were consecutively drawn into three other anticoagulants (using Vacutainer tubes) and processed in a three-part differential Coulter Counter S Plus IV. PLT aggregation is shown to be generally induced by Li-heparin but much less frequently by citrate solutions. Prevention is almost invariably achieved by acid citrate dextrose (ACD). To that end approximately 2.5 mL of sterile ACD was aseptically injected beforehand through the stoppers of plain 5 mL Vacutainer tubes without breaking the vacuum. After blood drawing, correction for dilution was made by comparing hemoglobin values in EDTA and ACD.

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Patients with monoclonal gammopathies comprise a heterogenous group. The few studies on incidence and follow‐up are single‐centre‐based and may reflect referral bias. To avoid this, all patients (n = 1275) in mid‐western Netherlands with a newly discovered paraproteinaemia in 1991, 1992 and 1993 were included in a population‐based registry and divided into four major diagnostic groups: multiple myeloma and plasmacytoma (n = 230, 18%), other haematological diseases (n = 141, 11%), paraprotein‐related internal diseases (n = 191, 15%) and monoclonal gammopathy of undetermined significance (MGUS, n = 713, 56%). To avoid a possibly erroneous diagnosis, patients who were classified as having MGUS but who did not undergo confirmatory bone marrow examination were included in a separate group ‘provisional MGUS’ (n = 524, 41%), whereas patients who did were classified as having ‘definite MGUS’ (n = 189, 15%). The ‘provisional MGUS’ patients were relatively older and had more often a poor performance status, but differences between this and the ‘definite MGUS’ group were otherwise small. Patients complaining of general malaise more often had a full work‐up of their paraproteinaemia. Bone pain, hypercalcaemia, high total protein, and high ESR occurred predominantly in the myeloma group, whereas fever or infection was less often seen in these patients. This registry of patients with paraproteinaemias provided valuable data related to all different diseases associated with paraproteinaemia.

The Sysmex XE-5000 is suitable for screening blood samples for the presence of elevated number of plasma cells in peripheral blood, but the actual quantification needs to be confirmed by flow cytometry.