Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085584 (encephalopathy)
 18,178 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We evaluated the CNS complications in 118 adults with acute leukemia who received IV high-dose Ara-C therapy. Fourteen (12%) had cerebellar signs, encephalopathy, seizures, or leukoencephalopathy. Symptoms usually occurred within 24 hours after the last treatment. Patients receiving a cumulative dose in excess of 24 g/m2 had more severe or irreversible symptoms. After lower cumulative doses, symptoms often resolved even though treatment was continued. The incidence of CNS complications of high-dose Ara-C is acceptable and is potentially reversible if appropriate precautions are taken.
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PMID:Central nervous system toxicity with high-dose Ara-C. 403 29

The Central Nervous System has often been classified as a "drug sanctuary" as most anticancer drugs do not achieve effective penetration of the blood-brain barrier. With more effective systemic chemotherapy programs (especially in acute leukemia in children), the incidence of meningeal tumor involvement has increased. Even though a number of systemically administered agents might be used in treating the CNS, only three have been used intrathecally with good clinical results: the antimetabolites methotrexate (MTX) and cytosine arabinoside (Ara-C) and the alkylating derivative thiophosphoramide (thio-TEPA). Drug distribution in the CSF which is injected by lumbar puncture does not generally allow for delivery of effective quantities of drug to the cisternae nor the ventricles. Thus direct intraventricular injection via a subcutaneously implanted (Ommaya) reservoir is necessary to achieve adequate drug levels in the higher CNS cavities. The peak ventricular concentration of MTX, which was administered by Ommaya reservoir, at a dose of 15mg/m2, was 2.5 +/- 0.9 X 10(-4)M, and remained as a level of 10(-6)M for 72 hours with a half-life of 10.5 hours. During an intravenous 6 hour-infusion at a dose of 750-3,000mg/m2, MTX concentration in CSF reached 8.2 X 10(-7)M to 2.7 X 10(-6)M. The drug content in CSF had a linear concentration related to the drug level in plasma. Intrathecal MTX and Ara-C frequently cause symptoms of meningeal irritation. Occasionally cases of weakness and paralysis and rare instances of severe encephalopathy may occur. The best established causes of these symptoms is high concentration of these drugs in the CSF, or prolonged exposure of the brain to low CSF concentration.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Pharmacokinetics of intrathecal chemotherapy and clinical problems]. 643 96

Depo cytarabine (DTC 101 [formerly identified as Depo/Ara-C]) is a slow-releasing, depot formulation in which cytarabine is encapsulated within the aqueous compartments of microscopic (DepoFoam) particles. A phase I trial of DTC 101, given intraventricularly, was conducted in patients with leptomeningeal metastasis. Nine patients were given 1 to 7 cycles of DTC 101 in doses ranging from 25 to 125 mg that were administered via an Ommaya reservoir into the lateral ventricle. The dose-limiting toxic reaction was encephalopathy that occurred at the 125-mg dose level. All toxic episodes but one were transient and reversible, with the total duration of toxicity lasting from 1 to 7 days. The ventricular concentration of free cytarabine released from DTC 101 into cerebrospinal fluid decreased biexponentially with an initial half-life of 7.2 +/- 1.7 (+/- SEM) hours and a terminal half-life of 140 +/- 49 hours. The cerebrospinal fluid was cleared of malignant cells within 3 weeks of initial therapy in five of six cytologically evaluable patients. The duration of response ranged from 2 to more than 14 weeks, with a median of over 11 weeks. In conclusion, DTC 101 appears to be a pharmacologically attractive agent for use against leptomeningeal metastasis. The toxic episodes that occur with this therapy are well tolerated by patients.
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PMID:Treatment of leptomeningeal metastasis with intraventricular administration of depot cytarabine (DTC 101). A phase I study. 844 4