Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Siblings, aged 9 and 7 years, had simultaneous onset of vomiting, disorientation, ataxia, and coma. Both children had prodromal symptoms of upper respiratory tract infections, and had been treated with large doses of aspirin. Laboratory data showed evidence of hepatocellular dysfunction, with an elevated serum ammonia level in one patient; salicylate levels were 50 and 44 mg/100 ml. The child who died had autopsy evidence of cerebral edema and fatty liver. The difficulty in clinically differentiating Reye syndrome from salicylate intoxication is discussed.
 ...
PMID:Acute encephalopathy in siblings. Reye syndrome vs salicylate intoxication. 125 38

Varicella may be associated with serious complications including encephalitis, Reye's syndrome, and drug toxicity. In this case, a 19-month-old child with varicella was brought to the family practice clinic by her parents when she began behaving abnormally. At the time of presentation the child exhibited dilated pupils, ataxia, urinary retention, and facial grimacing. The child's parents had treated her with acetaminophen, diphenhydramine syrup, colloidal oatmeal baths, and frequent applications of Caladryl lotion. The results of her immediate laboratory tests were within normal limits, and she was admitted to the hospital for observation. She recovered without therapeutic intervention. Although not available at the time of admission to the hospital, her diphenhydramine serum level was 1948 ng/mL. Diphenhydramine levels above 100 ng/mL have been associated with toxicity.
 ...
PMID:Diphenhydramine toxicity in a child with varicella. A case report. 164 15

This article describes the metabolic investigations to be applied in any clinical situation consistent with a late acute form of inborn error of metabolism: unexplained coma with or without focal neurological manifestations, recurrent vomiting with lethargy, episodes of ataxia with or without behaviour disorder, fits of psychiatric troubles. In each of these situations, careful medical history is of major importance searching for previous clinical manifestations such as episodes of coma, ataxia or vomiting, anorexia, failure to thrive, developmental delay, all very suggestive of metabolic disorder. The association of neurological symptoms and abnormal hepatic tests is also of great value and must not lead to the diagnosis of Reye's syndrome without considering a metabolic defect of fatty acid oxidation, urea cycle, respiratory chain, or Wilson's disease. When looking for an etiological origin, it is mandatory to collect all the biological information at the same time, also knowing that metabolic abnormalities may be mild and transitory, and that many of them are non specific (metabolic acidosis, hyperlactacidemia, hyperammonemia, hepatic tests disturbances) being encountered in collapsus, shock and multiple organ failure syndrome.
 ...
PMID:[Diagnosis of metabolic coma in children]. 784 29

Neuropsychiatric symptoms of hyperammonaemia include alterations of mood and personality, cognitive impairment, ataxia, convulsions and coma. The nature and severity of CNS dysfunction depend upon the aetiology and degree of hyperammonaemia, its acuteness of onset and the age of the patient. Neuropathological studies reveal Alzheimer type II astrocytosis in the adult hyperammonaemic patient, whereas hyperammonaemia in the infant resulting from congenital urea cycle disorders or Reye syndrome is accompanied by cerebral atrophy, neuronal loss and cerebral oedema. Several electrophysiological and biochemical mechanisms have been proposed to explain the deleterious effects of ammonia on CNS function. Such mechanisms include direct effects of the ammonium ion on excitatory and inhibitory neurotransmission and a deficit in cerebral energy metabolism due to ammonia-induced inhibition of alpha-ketoglutarate dehydrogenase. In addition, ammonia has been shown to interfere with normal processes of uptake, storage and release of various neurotransmitters. Ammonia disrupts monoamine storage, inhibits the high-affinity uptake of glutamate by both astrocytic and neuronal elements and activates 'peripheral-type' benzodiazepine receptors leading to the potential synthesis of neuroactive steroids in brain. On the basis of these actions, it has been proposed that ammonia disrupts neuron-astrocyte trafficking of amino acids and monoamines in brain. The increased formation of brain glutamine in hyperammonaemic syndromes could be responsible for the phenomenon of brain oedema in these disorders. Therapies aimed at either decreasing ammonia production in the gastrointestinal tract or increasing ammonia removal by liver or skeletal muscle are the mainstay in the prevention and treatment of the CNS consequences of hyperammonaemia. New therapeutic approaches aimed at correction of the neurotransmitter and cerebral energy deficits in these syndromes could hold promise for the future.
 ...
PMID:Effects of hyperammonaemia on brain function. 968 41

Children with acute encephalopathy (AEP) or acute encephalitis(AE) show variable findings in the clinical manifestations and on the neuroimaging. Patients with AE present variable symptoms: disturbance of consciousness, seizure, ataxia, dystonia, abnormal behavior, apnea, and others. This variability depends on the location of lesions including basal ganglia, brain stem, cerebellum, or cerebral gray/white matter. In AEP, MRI findings can be categorized into (1) severe brain edema, (2) acute necrotizing encephalopathy, (3) cortical necrosis that appears 4-5 days after the onset, and (4) others. Serum AST elevates in approximately 50% of AEP patients, and among them around 60% develops DIC. The high AST group includes Reye syndrome(RS), mimic RS and AEP with shock syndrome.
 ...
PMID:[Clinical variability in viral infection related acute encephalitis or encephalopathy]. 2140 Aug 54

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used agents in clinical practice. They are employed as anti-inflammatory, analgesic, and antipyretic agents for a wide spectrum of clinical conditions. Their anti-inflammatory properties are primarily due to inhibition of prostaglandin synthesis. In this paper we review the neurological effects associated with the use of NSAIDs. Acute CNS toxicity related to NSAID use is pervasive and varied. A prospective study looking at ibuprofen overdose noted that 30% of patients experience CNS effects ranging from drowsiness to coma. Case reports have identified numerous neurologic sequelae including ataxia, vertigo, dizziness, recurrent falls, nystagmus, headache, encephalopathy, and disorientation. Seizures have also been reported, mostly after overdose ingestions, but even therapeutic doses have occasionally been associated with seizures. One of the important neurologic side-effects attributed to the use of NSAIDs is aseptic meningitis. The clinical signs of drug-induced meningitis are similar to those of infectious meningitis and include fever, headache, photophobia, and stiff neck. The laboratory findings are also similar, including cerebrospinal fluid (CSF) pleocytosis of several hundred or thousand cells, mainly neutrophils, elevated levels of protein, normal or low glucose levels and negative cultures. Drug-induced meningitis is a transient disorder with an excellent prognosis. Most or all drugs used for the treatment of headache, including NSAIDs, may cause a condition known as medication overuse headache - a refractory chronic daily headache that tends to resolve following discontinuation of the analgesics. Reye's syndrome is a rare severe illness occurring mainly in children and adolescents and characterized by abnormal liver function, vomiting, and encephalopathy, with a mortality rate approaching 40%. The pathogenesis is currently unknown, but commonly the syndrome is preceded by a viral episode, with an intermediate latent period of 3-5 days. An association with aspirin use is strongly suggested. Aspirin, the classic and most commonly used NSAID, has a well-documented effect in inhibiting intravascular clotting, thus reducing the occurrence of ischemic strokes and other vascular events. NSAIDs, however, have a double impact on coagulation. On the one hand, most agents inhibit the synthesis of thromboxane in the platelets, thereby inhibiting coagulation. On the other hand, they also inhibit the production of prostacyclin by endothelial cells, resulting in a prothrombotic state. Selective inhibition of COX-2 by drugs such as rofecoxib (Vioxx) and valdecoxib (Bextra) results in specific inhibition of synthesis of prostaglandins participating in inflammation and was found to lead to vascular complications including an increased risk for stroke. The connection between inflammation and neuronal degeneration is well established. Most studies, including the prospective Rotterdam study, have found an inverse correlation between the use of NSAIDs and the risk for dementia. Two meta-analyses have found 40% and 25% reduction, respectively, in the risk of Alzheimer's disease among NSAID users. However, some large, well designed studies failed to confirm these results, and some even found that NSAID use is associated with cognitive decline. The clinical impact of NSAIDs on Parkinson's disease (PD) remains unclear. While some studies showed that chronic NSAID use is protective against PD, other studies could not confirm the existence of a significant relationship. A recent meta-analysis indicated that the use of non-aspirin NSAID, particularly ibuprofen, reduces the risk of PD by 15% while the use of aspirin did not show any effect.
...
PMID:Nonsteroidal anti-inflammatory drugs exposure and the central nervous system. 2436 21