Thrombocytosis

Complete blood count Slight elevation in white blood cell count with a normal differential slight anemia, thrombocytosis... 

Hydroxyurea is an oral drug that inhibits ribonucleotide reductase, which converts ribonucleotides into the deoxyribuon-cleotides used in DNA synthesis and repair. The time to peak concentrations of hydroxyurea is 1 to 2 hours after oral administration. Approximately 50% is degraded by the liver to form urea and respiratory carbon dioxide. The remainder is excreted by the kidney. The half-life ranges from 3.5 to 4.5 hours. Hydroxyurea has shown clinical activity in the treatment of chronic myelocytic leukemia, polycythemia vera, and thrombocytosis. The major side effects are myelo-suppression, nausea and vomiting, diarrhea, and constipation. Rash, mucositis, and renal tubular dysfunction occur rarely. 

Laboratory abnormalities that may be seen include normocytic, normochromic anemia thrombocytosis or thrombocytopenia leukopenia elevated erythrocyte sedimentation rate and C-reactive protein positive... 

Sequential determination of platelet counts in patients receiving vincristine during early studies unexpectedly occasionally revealed thrombocytosis, which could not be accounted for by systemic response to treatment alone 10,11). Ultimately shown to most likely be the result of increased megakaryocytic endomitosis II), the observation led to the use of vincristine, and later vinblastine, both alone and bound to platelets, in a variety of thrombocytopenic disorders. These include idiopathic thrombocytopenic purpura, thrombotic thrombocytopenic purpura, and chemotherapy-induced microangiopathic hemolytic anemia. 

As opposed to vinblastine, vincristine s hematologic effects are minimal. In fact, thrombocytosis is often seen following vincristine administration (10,25,26). Alopecia occurs in from 13 to 22% of patients given full doses of vincristine. Cutaneous effects are, however, more unusual and are a practical problem only when the drug is extravasated (21,22). The spectrum of vindesine side effects is similar to that seen with vincristine. 

Its primary indications are myeloproliferative disorders, including chronic granulocytic leukemia, polycythemia vera, and essential thrombocytosis. It is also used in combination with radiotherapy for head and neck cancer and for carcinoma of the cervix. Hydroxycarbamide is well absorbed after oral administration. It is in part metabolized in the liver and also excreted unchanged in the urine its elimination half-life is 2-5 hours. Its major toxicity consists of short lasting bone marrow depression. 

These are indolent neoplasms characterised by uncontrolled expansion in the erythron where additional hazards are added by the thrombocytosis and, to a lesser extent, leucocytosis. There is a specific point mutation in the Janus Kinase 2 or JAK 2 gene that better defines these cases. 

Hemotoxic activity. Seed oil, administered orally to human adults, produced thrombocytosis in children, the effect was inactivated by ultraviolet radiation . Hypercholesterolemic activity. Seed oil, administered by gastric intubation to rabbits at a dose of 0.4 g/kg, was inactive " . Male Wistar rats fed 12 or 24% sesame oil in the diet for 4 weeks were investigated. The rats on the 24% sesame oil diet had significantly lower lymphatic cholesterol and fatty acids . 

Schiff, E., and C. Hirscheberger. Thrombocytosis produced by a hitherto unknown substance the fat- SI153 soluble T factor . Amer J Dis Child 1937 53 32-38. 

Thermogenic. Producing heat. Thrombocytosis. Increased numbers of platelets in the peripheral blood. 

It is indicated in treatment of chronic granulocytic leukaemia, polycythemia vera, essential thrombocytosis, melanoma. 

The natural history of ineffectively treated CML is one of a triphasic clinical course. There is an initial chronic phase characterized by mature leukocytosis and/or thrombocytosis with some immature myeloid elements in the blood and frequent basophilia that is usually 56 years in duration. Subsequently, CML will transform into an acute leukemic phase that can have either a lymphoid or myeloid phenotype. Although transiently controllable with chemotherapy, the development of this blast crisis usually heralds the demise of the patient. Some patients will develop an accelerated phase after the chronic phase and prior to the blast phase that is characterized by decreased disease control and/or additional chromosomal abnormalities (6). 

Adverse Reactions Diarrhea, nausea Eosinophilia, positive Coombs test, thrombocytosis, agranulocytosis, hemolytic anemia, leukopenia, thrombocytopenia, prolonged prothrombin time Elevation of hepatic enzymes Rash, anaphylactic reaction Phlebitis at injection site... 

Inokuchi, K., Dan, K., Takatori, M., Takahuji, H., Uchida, N., Inami, M., et al. (2003) Myeloproliferative disease in transgenic mice expressing P230 Bcr/Abl longer disease latency, thrombocytosis, and mild leukocytosis. Blood 102, 320-323. 

Platelet counts above 400,000/pil are referred to as thrombocytosis, Thrombocytosis is classified as being either primary or secondary, Primary thrombocytosis or essential thrombo-cythemia is associated with chronic myeloproliferative disorders such as chronic myeloid leukemia, polycythemia vera, and agnogenic myeloid metaplasia. Exclusion-based diagnosis of essential thrombocythemia is made when patients... 

Gabor M, Piukovich I, Lacsan I. 1962. Experimental thrombocytosis with o-nitrophenol. Naturwissenschaften 49 470-471. 

Thrombocytosis and thrombocytopenia have both been reported. 

Thrombocytosis (774 x 109/1) occurred in a middle-aged man taking clozapine (167). 

In a 40-month-old boy a withdrawal syndrome with neurological symptoms was accompanied by thrombocytosis, which peaked at 1230 x 109/1 (45). Recovery from the withdrawal syndrome was accompanied by normalization of the platelet count. The relevance of this change in platelet count was not clear. The boy had also been given fentanyl, and the authors suggested that the combination of midazolam with fentanyl should be used with caution. 

A newborn girl born of an HIV-positive mother who took antiretroviral drugs and methadone during pregnancy developed a methadone abstinence syndrome at day 7 (43). She was HIV-negative and was treated symptomatically for 15 days with chlorpromazine. The platelet count was 1049 x 109/1 on day 17 and fell progressively to 290 x 109/1 at 8 weeks. The authors suggested that the thrombocytosis had been secondary to intrauterine methadone exposure. 

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