Changes in response to antiaggregatory treatment in patients with myeloproliferative neoplasms: a sequential study using multiple electrode aggregometry.

In the present study, we used multiple electrode aggregometry (MEA) to investigate the response to aspirin and clopidogrel treatment, and its potential changes over a long-time disease course in patients with myeloproliferative neoplasms (MPNs). arachidonic acid (ASPI), ADP, and thrombin receptor activating peptide (TRAP) tests were performed at two timepoints between 32-50 months in 21 patients with MPN and 1-46 months in 29 controls. We further checked the medical records of the participants to identify a potential correlation of changes in the treatment response with clinical events.

The cytospin technique improves the detection of calcium pyrophosphate crystals in synovial fluid samples with a low leukocyte count.

In synovial fluids (SF) with low leukocyte or/and crystal counts, important features may be missed, if exclusively smears are examined by polarized microscopy. That may be overcome by cytocentrifuges, which use low-speed centrifugal force to concentrate cells onto a glass slide and thus enhance the number of cells per high power field (HPF). We compared the calcium pyrophosphate (CPP) crystal counts in cytospin preparations with those in common smears of SF.

Pseudoeosinophilia of synovial fluid is caused by crystals mimicking the distinct light scattering fractions of eosinophilic granules.

Background: Automated leukocyte differential counts of synovial fluid (SF) can be influenced by laboratory artefacts. Pseudoeosinophilia of SF has recently been first described in association with monosodium urate and calcium pyrophosphate crystals. This study compared automated measurements of the percentages of SF leukocyte fractions by two haematology analysers in order to elucidate the underlying mechanism of pseudoeosinophilia.

Calcium pyrophosphate and monosodium urate crystals in synovial fluid as a cause of pseudoeosinophilia.

Background: Synovial fluid (SF) leukocytes can be counted microscopically in a Neubauer chamber or by automated procedures using haematology analysers. Knowledge of laboratory artefacts is crucial for the correct interpretation of results obtained using automated methods. SF pseudoeosinophilia has recently been described as a new artefact in patients with crystal-related arthropathies.

Evaluation of platelet function and pharmacological platelet inhibition in patients with myeloproliferative disorders using multiple electrode aggregometry.

Background: The aim of this study was to describe platelet aggregation characteristics by multiple electrode aggregometry (MEA) and to evaluate MEA for its potential to detect platelet dysfunction and response to anti-aggregatory drugs in patients with myeloproliferative disorders (MPD).

Methods: We compared the platelet response to arachidonic acid (ASPI test), adenosine diphosphate (ADP test) and thrombin receptor activating peptide (TRAP test) in hirudin-anticoagulated blood of 55 patients with polycythaemia vera and essential thrombocythaemia and 75 controls.

Results: Comparing MPD patients and controls no statistically significant difference indicative of platelet dysfunction was found in MPD patients.