An einer unausgewählten Population von 2040 Probanden (1075 Männer, 965 Frauen) wurden die Volumenaktivitäten der Enzyme* GOT, GPT und AP entsprechend den Empfehlungen der Deutschen Gesellschaft für Klinische Chemie bestimmt. Engen Zusammenhang mit den Enzymaktivitäten zeigten die Größen y-GT, Glucose, relatives Körpergewicht und Alter. Durch Eliminierung von Probanden mit pathologischen Werten der signifikanten Einflußgrößen y-GT, Bilirubin, Cholesterin, Glucose und Hämoglobin wurde eine Referenzgruppe von 1376 Personen (708 Männer, 668 Frauen) gebildet. Die bei diesen Probanden erhobenen Enzymaktivitäten dienten zur Schätzung der 0,05-und 0,95-Quantile unter zusätzlicher Berücksichtigung von Lebensalter und Gewicht. Es ergaben sich für Normalgewichtige folgende Referenzwerte im Serum: GOT < 19 U/l (Männer)

Reference values for the revised standard method for determining N-acetylcysteine (NAC) activated creatine kinase (CK) activity in serum are presented, based on samples from 432 out-patients and 423 in-patients of either sex. CK activity was not age-related. The suggested range of normal values for serum CK activity, measured by the revised standard method at + 25 degree C, is 10--70U/l for females and 10--80U/l for males. Where an elevation of serum CK activity is of uncertain cause, the CK/GOT ratio had been recommended, additional to the CK-MB isoenzyme, for distinguishing between damage to heart and skeletal muscle. The significance of this ratio was checked with the revised standard CK method and the optimized GOT determination. The point of separation between myocardial and skeletal muscle damage is 10 by this methods. In order to use this ratio, total CK activity must be over 150 U/l and liver disease or secondary liver involvement must have been excluded. The CK/GOT ratio gains in importance through findings which limit the specificity of CK-MB as a purely myocardial (infarct)-specific isoenzyme.

Diabur-Test 5000, a new test strip for urinary glucose, permits the accurate measurement of up to 5% glucose concentrations in urine. In a survey carried out at 12 diabetes centers in Europe, the new test strip was tested in laboratory trials and routine self-monitoring. There was good agreement between the test strip and the quantitative glucose determination on 4105 urine samples in the laboratory trials. A total of 185 patients used Diabur-Test 5000 for self-monitoring; nearly all reported favorably on the new test strip. Both the laboratory tests (on 1677 urine samples) and self-monitoring (on 4309 urine samples) showed Diabur-Test 5000 to be more sensitive compared with other rapid diagnostic tests. The new test strip is highly suitable for the determination of urinary glucose, particularly in routine self-monitoring.

In the Reflotron Amylase dry-reagent carrier system (Boehringer Mannheim GmbH) a new substrate is used for determining total amylase (EC 3.2.1.1) activity:indolyl-alpha-D-maltoheptaoside. The procedure shows low imprecision (median CV less than 3.2%), and results for sera, plasma, and capillary and venous blood (y) correlate well with those of a conventional alpha-amylase method involving p-nitrophenyl (PNP)-maltoheptaoside substrate (x) (for 209 blood samples: y = 0.981x + 9.7; r = 0.994). Correlation was also excellent with a method involving maltotetraose as substrate (r = 0.987). Attachment of an indoxyl residue rather than a PNP group to the maltoheptaoside did not affect the substrate response to pancreatic or salivary isoenzyme activity. Therefore, the relative proportion of these isoenzymes did not affect the correlation between the Reflotron Amylase reagent carrier and the alpha-amylase PNP-maltoheptaoside method. With a reaction time of less than 3 min, this system is especially suitable for amylase determination in situations where a prompt result is required.

Screening 720 morning urinary samples for WBC, RBC and protein by test-strip, the number of subsequent microscopic examinations of urinary sediment was reduced to about half, without missing any significant number of clinically significant findings (4.4%). On the other hand, a large number (21.3%) of cases with obviously false-negative sediment findings were revealed. These were largely due to lysis of WBC and RBC, as well as poorly standardized methods of examining urinary sediment. But they could also have been due to differences in subjective criteria employed by the technicians. Our results indicate that using test-strips for screening, clinical routine examination can be rationalized, taking about half the time needed for sediment examination, with more potentially significant findings being discovered than missed.