1915 Journal of the American Medical Association  
to be known or answerable at a given age, were added (from the writings of Ziehen, Meumann, Gaupp Bobertag and others35). The age norms must still be considered but approxi¬ mate, for reasons already given, the varying normal fluctuations in intelligence, wide differences in opinions still maintained as to the difficulty or overeasiness of certain questions, the unsettled problem of possible racial or environmental variations, the differences found in children tested in higher and lower social
more » ... r and lower social classes, etc. There is even a possibility that the intel¬ ligence variations in individuals of the same age are greater than we assumeat least the contrary has not been· proved so that we possibly have no normal age norm of intelligence or of the faculties comprising intelligence. This, too, must be borne in mind. So much for the present in the way of criticism of methods, etc. Elsewhere the facts making up this test sheet will be fully described and discussed, and thè importance of the faculties themselves in their interfunctioning studied in relation to mental evaluations. During the past year I have had the opportunity of studying the luetin reaction somewhat in detail on patients admitted to the neurology service of the Hospital of the University of Michigan. As a result of this study, it was attempted to determine the value of the luetin reaction in the diagnosis of syphilis, the proper technic and the influence of various factors such as medication, etc. Observations were made sometimes repeatedly in a series of 235 cases from the neurologic clinic of the University of Michigan, service of Dr. C. D. Camp. This reaction was also tested in a series of sixteen cases admitted to the clinic for dermatology and syphilology, University of Michigan, service of Dr. Udo Wile. The technic followed is that described by Dr. Noguchi, namely, the intradermal injection of a 1:1 dilution of luetin material with saline. The cases were taken indiscriminately and were both luetic and nonluetic. In fact, a large percentage were nonsyphilitic from every standpoint, including cases of pernicious anemia, brain tumor, hysteria, traumatic neurosis, muscular dystrophy, sciatica, chronic nephritis, neuritis, epilepsy, exophthalmic goiter, multiple sclerosis, arteriosclerosis, disturbances of the internal secretions, etc. The reaction was observed on an average of from eight to ten days, and in many for a period of several weeks. A detailed report of the various factors mentioned above will be deferred to a later communication. In this report I wish to call attention to the influence which potassium iodid has on the luetin reaction. The fact that the administration of potassium iodid will cause a positive luetin reaction which otherwise 35. It was astonishing enough how little an immense amount of reading brought to light and how little could be got from Binet himself in the faculties of combination, attention, feeling, etc. * From the Neurologic Clinic, Hospital of the University of Michigan. would have been negative in nonsyphilitic individuals seems not to have been observed. Furthermore, the fact that this reaction is indistinguishable from the reaction indicative of syphilitic infection is a matter of considerable importance to those using the luetin reaction as a means of diagnosis. If the patient suspected of being syphilitic has received potassium iodid either before, during or shortly after the use of the test, the result is entirely unreliable. The fact that the iodids are capable of causing this reaction to the intradermal injection of luetin may throw some light on the pharmacologie action of the iodids. Where potassium iodid is administered to patients who have undergone a luetin test, it is found that in practically every case a pustular or nodular reaction results ; in this series only one has failed to respond. As a rule, relatively large doses are required to bring about this condition, on an average of from 20 to 30 grains three times daily ; but a great deal appar¬ ently depends on the individual's susceptibility, a positive reaction being obtained in several cases with small doses, 10 grains three times daily. This reac¬ tion is characterized by a marked areola, with red¬ ness, edema and swelling appearing in a very few hours after the injection and gradually increasing in its manifestations. There is a firm, central nodule of a bright red color raised above the surface of the skin and extending deeply ; this nodule develops an area of central necrosis which, in turn, is in most cases replaced by a hemorrhagic pustule. The intensity of the reaction varies in different individuals, but always goes on to the pustular stage if the drug is continued. This pustule, on discharging, soon heals, and marks the end of the reaction. If only small doses of potassium iodid be given, or if large doses be given for a short time, and the drug is stopped short of the pustular stage, there is a similar reaction to the iodid but no discharge, and the lesion involutes, to reappear again on subsequent readmin¬ istration of the iodid. This has been demonstrated in several cases, and with proper manipulation I think can be obtained in practically every case. It is interesting to note that the period elapsing between the injection of the luetin material and thè ingestion of the potassium iodid may vary widely with still positive results. In one case with a negative luetin test, potassium iodid was given in small doses about two months later, and the old seat of the test immediately developed an areola with a firm, red, central nodule. The potassium iodid was then dis¬ continued, and the reaction stopped short of the pus¬ tular stage and underwent complete involution. Sub¬ sequent administration of potassium iodid several weeks later resulted in a similar response. If potas¬ sium iodid is administered at the time of the injection of the luetin, an intense reaction develops in from three to eight days. A similar result ensues if the patient has been receiving potassium iodid previously, but even more quickly. If, however, the patient has received potassium iodid over a considerable period, but none previous to the luetin test, a positive luetin will still result, if too long a time has not elapsed from the time of the administration of the iodid. In one case a marked reaction was obtained three weeks after the potassium iodid was discontinued. A reaction similar to the luetin can be obtained by the injection intradermally of other substances, such as agar, starch, etc., and the administration of potas-
doi:10.1001/jama.1915.02580050032008 fatcat:udmdn4pcpncvfeqdqwt65uujum