Thrombocyte count

In contrast to administration in earlier treatment elements applied in childhood ALL protocols (e.g., consolidation or extra-compartment therapy) where thiopurines are given at fixed doses, in maintenance both 6-MP and methotrexate doses are adjusted according to absolute leukocyte or neutrophil and platelet counts. Current BFM dose modification guidelines for maintenance treatment in childhood ALL call for an absolute leukocyte count in a target range of 2-3 x 10 /L (2, 57). Minimal requirements for starting maintenance treatment are an absolute leukocyte count of > 1 x 10 /L with at least 0.2 X 10 /L neutrophils and 50 x 10 /L thrombocytes (counts not decreasing). 

Hematological Effects. Low serum potassium level was observed in a 22- year-old factory worker accidentally exposed by acute inhalation to barium carbonate powder (Shankle and Keane 1988). Altered hematological parameters were observed in rats following inhalation for an intermediate exposure period to 3.6 mg barium/m as barium carbonate dust (Tarasenko et al. 1977). Reported changes included decreased blood hemoglobin, decreased thrombocyte count, decreased blood glucose, decreased albumin, increased leukocyte count, and increased blood phosphorus. 

Quick s value, thrombocyte count, bleeding time... 

Thrombocytosis is a (generally temporary) rise in the thrombocyte count. Thromboembolic complications may arise. This disorder occurs in hepatocellular carcinoma, for example, following splenectomy or portosystemic anastomosis as well as after haemorrhage or cortisone therapy. 

Laboratory parameters Once the initial blood sample has been taken to assess the blood loss, the following values must be determined immediately blood group, thrombocyte count, Quick s value, electrolyte profile and creatinine as well as fibrinogen and AT III levels. 

Volume replacement should not increase the CVP beyond 4-5 cm H2O or the haematocrit beyond 35%, since there is a danger of recurrent bleeding from the oesophageal varices in the event of overcompensation. Haemostasis parameters (e.g. thrombocyte count. Quick s value, fibrinogen, AT III) must be continually monitored, so that any need for volume replacement is recognized immediately. A torsade de pointes (special form of ventricular tachycardia) may arise in the case of an electrolyte imbalance combined with vasopressin and neuroleptics. (88) (s. fig. 19.8)... 

The relation between the toxicity and pharmacokinetics of flucjdosine has been investigated in a retrospective study in 53 patients in an intensive care unit (17). Thrombocjdopenia, as a marker of bone marrow depression, was associated with a reduced clearance of flucytosine the lowest thrombocyte count was linearly related to the clearance of flucytosine. Patients with flucytosine concentrations over 100 pg/ml were at higher risk of thrombocytopenia and raised hepatic transaminases than those who did not exceed this threshold. In a second study, the authors corroborated their earlier findings and showed a significant relation between the lowest thrombocyte counts and thrombocyte counts predicted on the basis of the creatinine clearance in a new set of patients admitted to the intensive care unit (18). 

The anemia of injury with decrease in hemoglobin, elevation of erythrocyte sedimentation rate, and a loss of erythrocytes from the effective blood volume have been the subject of recent studies by Gelin and his collaborators (Gla-G4). Furthermore, immediately consequent on the injury the white cell count is usually elevated, and the thrombocyte count is decreased (R4). 

Complete blood count (white and red blood cell counts, differential leukocyte counts, thrombocyte counts, haemoglobin concentration, haematocrit, red cell indices) will provide information on haematological status and inflammatory conditions. 

IV. Diagnosis of benzene poisoning is based on a history of exposure and typical clinical findings. With chronic hematologic toxicity, erythrocyte, leukocyte, and thrombocyte counts may first increase and then decrease before the onset of aplastic anemia. 

Some studies showed decreases of thrombocyte counts in car painters and paint industry workers, other studies, however, recorded no changes.Studies concerning effects of paints on the white cell and thrombocyte counts were inconsistent. A decrease of white cells was described in several studies" and a lymphocytosis was noted by Angerer and Wulf Elofsson et al., however, recorded no changes in white cell counts. Additionally, myelotoxic effects of solvents were shown, especially for benzene. 

C) Laboratory tests. A complete blood count including a leukocyte count with differential, a quantitative thrombocyte count, hematocrit, hemoglobin, erythrocyte count and erythrocyte indices (MCV, MCH, MCHC). The results of these tests shall be reviewed by the examining physician. 

Splenectomy in GD shows the typical sequelae of this procedure. The transient elevation of the thrombocyte count may, however, last longer than that observed after splenectomy for other reasons. Elimination of thrombopenia by splenectomy is independent of associated bone marrow disease and occurs even with marked infiltration by GC (Pick 1926, Davidsohn 1928, Bonta 1929, Hunter and Evans 1929, Carling et al. 1933, Logan 1941). An increase in circulating white cells may persist for months with counts up to 30000. Herrlin and Hillborg (1962) saw recurring leukocytosis 4—5 years after splenectomy. There is also some improvement of anemia after splenectomy. 

Thrombocyte count and function is normal with the exception of the case of WoHNLiCH (1949), in which the diagnosis of ACD is not certain. A bleeding tendency or specific abnormalities of the blood clotting mechanism have not been reported. Findings from bone marrow biopsies will be reported in the section on pathology (see page 344). 

Chlorpheniramine is considered to be a relatively harmless drug in view of its widespread use and the rarity with which serious side effects are reported in the literature. In addition to the cases of facial hyperkinesia discussed above Deringer and Maniatis (26 -) described a 32-year-old patient who developed pancytopenia after medication with a preparation of chlorpheniramine and phenylpropanolamine. A marked decrease of the number of platelets and leukocytes occurred. A year later the patient was prescribed chlorpheniramine alone after which the white blood cell and the thrombocyte counts again showed a significant fall. The chlorpheniramine was discontinued and 3 days later the platelet count had risen to a... 

A man with pulmonary sarcoidosis developed purpura and thrombocytopenia 7 days after routine fluorescein angiography with 10 ml of 5% fluorescein sodium. The patient recovered. When thrombocyte counts were performed before and 2 weeks after fluorescein angiography in 29 clinical subjects, a marked decrease in thrombocytes was observed in 2 subjects. 

Okawada, N., Yachi, M., Kajio, T., Urano, H. and Eto, M. (1976) Drug induced purpura. Report of a case and thrombocyte count following intravenous fluorescein (Japanese). Jap. J. din. Ophthal, 30,103. 

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