Radiocontrast interference in screening tests for genetic-metabolic diseases.

Screening tests for genetic metabolic diseases remain extremely useful due to their rapidity, ease of interpretation and substantial reduction of cost. However, interferences in these tests are still a source of concern in laboratory medicine. Cost considerations have so compressed the duration of the medical work-up that the administration of radiologic contrast may often antedate the collection of body fluids for genetic-metabolic testing. It has been found that under these circumstances, certain contrast media may interfere with the urinary studies of amino acids, organic acids, and tests involving ultraviolet absorption such as those concerned with purines, pyrimidines, and related compounds. The consequences of interference may be misdiagnosis, repeated testing, extensive and expensive work-ups, and unnecessary delay and anxiety for the family. As in all testing, it is prudent to avoid medications and atypical diets, if possible. In the case of contrast media, it is a simple matter to collect samples for analysis prior to the administration of radiocontrast so as to avoid the pitfalls and yet not delay the diagnostic work-up.

Objectively measured hyperactivity--II. Caffeine and amphetamine effects.

Errors of commission and omission, chair movements, and reaction times were assessed in fifteen previously diagnosed hyperactive children on a Continuous Performance Test after four drug regimens: amphetamine at doses of 1.6 and 5.0 mg twice a day, as well as 300 mg caffeine administered alone and with 1.6 mg amphetamine twice a day, produced significant reductions in errors of commission and increased reaction times in those children scoring 24 or more on the Conner's Abbreviated Parent Questionnaire. In addition, subjective symptoms on this questionnaire were significantly reduced by all drug treatments. The high (600 mg) daily dose of caffeine was observed to significantly control hyperactive symptoms, however, it also produced a number of side effects as well.

Objectively measured hyperactivity--I. Comparison with normal controls.

Seventy-five normal (control) children were compared to 15 hyperactive children on a Continuous Performance Test over an eight-week period. The control children were observed to have a relatively constant number of correct responses, chair movements, and reaction times throughout the testing period. However, when the hyperactive children were differentiated according to their scores on the Conner's Abbreviated Parent Questionnaire, those children scoring one standard deviation above the normative mean were later revealed to have more errors of commission and omission, chair movements, and a longer reaction time than did the normal control children.

Binocular pattern stabilization by afterimage technique: reliability of children's time-dependent judgments of chromatic features.

To investigate visual afterimage technique as a means of producing retinally stabilized pattern, children's judgments of time-dependent shifts in chromatic appearance of random-dot configurations were twice examined within a 3-wk. interval. 13 subjects, aged 7 to 12 yr., were very consistent (r = .93) in their test-retest response times. This supports the belief that after image procedures can be developed as a reliable means of studying developmental aspects of stabilized pattern perception.

Cerebro-hepato-renal syndrome. Report of a case with histochemical and ultrastructural observations.

A new case of the cerebro-hepato-renal syndrome is being reported. The neuropathologic changes consisted of developmental abnormalities of cerebral and cerebellar cortex and of the inferior olives. In addition, there were metabolic changes in the central nervous system, indicated by an accumulation of lipid within histiocytes of free in gray and white matter, deficiency in myelination and gliosis of the white matter, and marked proliferation of protoplasmic astrocytes in the gray matter. A unique feature of this case was the presence of numerous clusters of lipid-filled macrophages and occasional cholesterol crystals in the molecular layer of the cerebellum. The histochemical reactions and ultrastructural appearances of the lipid deposits are suggestive of accumulation of several different types of lipids.