Neurological abnormalities

The a-oxidation pathway is defective in Refsum s disease, an inherited metabolic disorder that results in defective night vision, tremors, and other neurologic abnormalities. These symptoms are caused by accumulation of phytanic acid in the body. Treatment of Refsum s disease requires a diet free of chloro-... 

Severe, acute respiratory acidosis produces a variety of neurologic abnormalities. Initially these include headache, blurred vision, restlessness, and anxiety. These may progress to tremors, asterixis, somnolence, and/or delirium. If untreated, terminal manifestations include peripheral vasodilation leading to hypotension and cardiac arrhythmias. Chronic respiratory acidosis is typically associated with cor pulmonale and peripheral edema. 

Purine nucleoside phosphorylase (PNP) deficiency engenders a combined immunodeficiency and neurologic abnormalities and is usually fatal in childhood (G4). Patients with PNP deficiency have profound lymphopenia and a small thymus with poorly formed Hassall corpuscles. Lymphocyte enumeration shows markedly decreased numbers of T cells and T-cell subsets, with normal percentages of B cells. Point mutations and a splicing mutation have been identified in some PNP-deficient patients (H4). 

A casualty with known exposure to carbon monoxide blood agents, who was initially unconscious but has regained consciousness or a casualty who shows neurological abnormalities such as dizziness, confusion, or hallucinations, has cardiac arrhythmias, bronchospasm or complains of severe headache, difficulty in breathing or chest pain. If available, breath measurement indicates that the blood carbon monoxide level exceeds 20%. 

It is normally found in the Middle East, Africa, and Asia, and is spreading through North America. The natural reservoirs are birds and mosquitoes. Other than sudden death, most birds exhibit little or no signs of disease. If present, typical symptoms include neurologic abnormalities and emaciation. Disease may also be present in household pets such as dogs and cats. This is a biosafety level 3 agent. 

Uncomplicated UTIs are not associated with structural or neurologic abnormalities that may interfere with the normal flow of urine or the voiding mechanism. Complicated UTIs are the result of a predisposing lesion of the urinary tract such as a congenital abnormality or distortion of the urinary tract, a stone, indwelling catheter, prostatic hypertrophy, obstruction, or neurologic deficit that interferes with the normal flow of urine and urinary tract defenses. 

Herbert R, Gerr F, Luo J, et al. 1995. Peripheral neurological abnormalities among roofing workers Sentinel case and clinial screening. Arch Environ Health 50(5) 349-354. 

Reflex action can be objectively examined. Measurement of the so-called electrical conduction velocity of motor nerves gives an indication of whether peripheral nerves have been damaged. Electromyography, or examination of the electrical activity of the muscle, and electroencephalography (EEG) can also be used to detect the presence of neurologic abnormalities. And, at least in animal tests, detailed pathological examination of neural tissue can be performed on animals that are killed. 

In the neurotoxicity study (OECD TG 424/EU Annex B.43), the animals are tested to allow the detection or the characterization of behavioral and/or neurological abnormalities. A range of behaviors that could be affected by neuro toxic ants is assessed during each observation period. At the end of the test, a subset of animals of each sex from each group are perfused in situ and sections of the brain, spinal cord, and peripheral nerves are prepared and examined. 

K4. Kocen, R. S., Lloyd, J. K., Lascelles, P. T., Fosbrooke, A. S., and Williams, D., Familial alpha-lipoprotein deficiency (Tangier disease) with neurological abnormalities. Lancet 1, 1341 (1967). 

Epilepsy (or epilepsies, since markedly different clinical entities exist) is a common neurological abnormality affecting about 1% of the human population. Epilepsy is a chronic, usually life-long disorder characterized by recurrent seizures or convulsions and usually, episodes of unconsciousness and/or amnesia. Table 32.1 illustrates the major types of epileptic seizures. Patients often exhibit more than one type. In most instances, the cause of the seizure disorder is not known (idiopathic epilepsy), although trauma during birth is suspected of being one cause. 

The most common early manifestations of digoxin toxicity are G1 disturbances (anorexia, nausea, vomiting) and neurologic abnormalities (fatigue, headache, depression, weakness, drowsiness, confusion, nightmares). 

Language and speech. Speech spontaneity, articulation, vocabulary, and prosody should be noted. Pedantic speech may be a symptom of Asperger s disorder or of a nonverbal learning disorder. Diminished speech may be the result of depression or autism. Excessive speech may be the result of anxiety, ADHD, or hypo-mania. Unusual speech may be an early sign of neu-rodevelopmental vulnerability to psychosis. Slurred speech may be evidence of a neurologic abnormality or a medication side effect. 

Tremor is one of the most common adverse effects of lithium treatment, and it occurs with therapeutic doses. Propranolol and atenolol, which have been reported to be effective in essential tremor, also alleviate lithium-induced tremor. Other reported neurologic abnormalities include choreoathetosis, motor hyperactivity, ataxia, dysarthria, and aphasia. Psychiatric disturbances at toxic concentrations are generally marked by mental confusion and... 

Vitamin B12 (cobalamin) serves as a cofactor for several essential biochemical reactions in humans. Deficiency of vitamin B12 leads to megaloblastic anemia (Table 33-2), gastrointestinal symptoms, and neurologic abnormalities. Although... 

Maintenance therapy consists of 100-1000 meg intramuscularly once a month for life. If neurologic abnormalities are present, maintenance therapy injections should be given every 1-2 weeks for 6 months before switching to monthly injections. Oral vitamin B12-intrinsic factor mixtures and liver extracts should not be used to treat vitamin B12 deficiency ... 

Abel, Ernest L. Fetal Alcohol Abuse Syndrome. New York Plenum Press, 1998. Describes the causes and consequences of fetal alcohol syndrome, including pregnancy-related problems (such as spontaneous abortion), birth defects, and neurological abnormalities. There is also discussion of how to diagnose the condition and how to estimate its prevalence. 

Holman, R.T., Johnson, S.B., and Hatch, T.F. 1982. A case of human linolenic acid deficiency involving neurological abnormalities. Am. J. Clin. Nutr. 35, 617-623. 

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