The development of the laboratory diagnosis of syphilis is descriptionbed. Sero-negative syphilis is referred to, and the evaluation of the negative test is discussed, particular reference being intended to the negative test on serum drawn from suspect cases. The causes of false positive serologic tests for syphilis are noted, and their interpretation is discussed. Latent syphilis is defined, its frequency is shown and by indicating that its diagnosis is usually possible only by serologic testing, some advantages of routine testing are pointed out. Warning is given against the adoption of a mental attitude which will only countenance syphilis in the lower social groupings, or which will allow all symptoms to be interpreted as syphilitic in the presence of a positive serologic test due to syphilis.
Four cases have been reported, in two of which the diagnosis of diabetes had been missed, and in the other two a wrong diagnosis of diabetes had been made. To avoid such errors: The possibility of diabetes should be considered whenever there is a family history of it. In these cases (even if the urine has been found free of sugar) a fasting blood sugar and if necessary a glucose tolerance test should be done. A suspected hypoglycaemic condition should either be verified or excluded by prolonged glucose tolerance test. In cases of glycosuria a fasting blood sugar test should be taken. If the result is normal, at least a further blood sugar concentration 2 1/2 hours after a heavy carbohydrate meal must be determined. A diabetic glucose tolerance curve must be viewed with suspicion if it has been taken whilst the patient has been on a restricted diet, and should be repeated after the patient has been put on a diet for at least one week with sufficient carbohydrates.