Differential diagnosis

“ In order to make a differential diagnosis, however, it is not only necessary to know the structure and functions of the organs in health, but to adopt a rigid system of details of examination, without which successful results can not be reached. ”

“ DIFFERENTIAL DIAGNOSIS.—In view of what has been already stated regarding the numerous clinical types found in disseminated sclerosis, it is easily understood why the diagnosis of this disease is becoming more and more uncertain: every new set of researches removes some one or several of the old and cherished landmarks ”

“ It is imperative to create an environment or a culture that reduces stress for the physician, to always use differential diagnoses even when the diagnosis seems obvious, and to train humble physicians who are willing to listen to patients and other team members so that they can revisit the evidence when they are questioned about their diagnosis or management of patients. ”

“ A certain disease may be accompanied by all kinds of other disturbances of the functions of the organ. Very seldom are we faced with the presence of "pure" disease. Therefore, we are bound to conclude that only the worker in a hospital is in a position to judge, to what extent serological investigations can be applied for testing the functions of an organ. In this case two aims have to be distinguished. The serological diagnosis can, in many cases, widen our understanding of the disturbances occurring in a given disease. ”

“ At the same time we must admit the possibility of mixed forms, where the functional element is linked with primary or secondary organic disease, and perhaps their occurrence is more general than is ordinarily imagined. We repeat, however, that rigorous and lengthy investigation alike of the psychical and the somatic phases of the condition, embracing the state of the reflexes, will usually furnish sufficient information to facilitate the question of diagnosis and justify a positive statement. ”

“ On the other hand it may be stated that, without multiplying illustrations, there are very numerous instances in which the subjective indications (symptoms) of organic disease are so prominent and the distress so urgent as to appear conclusive proof of imminent danger. A test of a few moments' time will make the correct diagnosis and furnish a comforting stethoscopic negative.
Disorders of the heart, although of less frequent occurrence than those of the lungs, are of equal importance and require the best skill of the examiner. ”

“ Troubles which would lead the patient to go to the specialist primarily, without consulting his family physician, should receive little attention.
Two other classes of lesions in such organs as are usually handed over to specialists should receive attention in the undergraduate course—those which are apt to cause remote or reflex disturbances, and those which are definitely symptomatic of central lesions. The first should, in my judgment, be dwelt upon only to such an extent as to enable the student to know causative relation and method of diagnosis. ”

“ Yet there are signs that we are entering on a new phase, and that a realisation of the importance of early diagnosis is slowly permeating through the medical profession. In America we see an increasing insistence on the use of detailed and specialised laboratory methods for exact diagnosis ”

“ The necessity of investigating accurately the condition of the great central organ of menstruation, and of ascertaining to what particular disease the derangement of the flow is to be attributed, will bear repetition. That an anatomical or pathological diagnosis can always be made is not maintained, but when examination has failed to reveal a basis for such a diagnosis, the practitioner should distrust his position and consider his diagnosis provisional only, awaiting more information from renewed examination or from further progress of the case. ”

“ Often later observations alone will show, whether the serological diagnosis is really correct. It will be particularly necessary to make our clinical description of individual cases as thorough as possible. The serological diagnosis of diseases of the nervous system will attain a great measure of success, when it enables us to isolate diseases, hitherto considered identical, according to the presence of particular defensive ferments, and to find that the clinical course of the disease corresponds with this. ”

“ The basis of a positive diagnosis is the exclusion, by the absence of their physical signs, of inflammatory affections and lesions of structure.
The physician who undertakes to diagnosticate functional disorders of the heart by symptoms alone—that is, without physical exploration—must often be in doubt, and if not prudently distrustful of his ability as a diagnostician, he is liable to commit errors which are sometimes extremely unfortunate. I was requested to see a young woman who was represented as suffering from a disease of the heart from which she might die at any moment. ”

“ These researches naturally do no more than imply a rapid advance into unknown territory. There are still many stages to go over again, before we can arrive at a definite picture. A serological examination must be first employed, and the clinical diagnosis, which is generally more uncertain, will be compared with it. ”

“ He knows the anatomy of the chest; he begins to know the normal heart sounds and areas of dullness; but he cannot yet fit his various items of knowledge together. Then comes the experienced physician and perhaps makes a complete diagnosis without any examination at all, merely from hearing the patient speak or cough. He has the same facts as the student, but he has acquired the faculty of instantly connecting an abnormality of function with its correleated anatomical change. ”

“ Of several physicians, all but one are mistaken in the diagnosis of a case. Why do they differ? Every disease is characterized by a multitude of{150} symptoms. Some of them are obvious, so that no one can fail to notice them: the complaints of the patient. Others are more hidden, but no less important. The physician must search for them. Each symptom, for example, fever, lack of appetite, dizziness, megalomania, may appear in very different diseases. A definite group of symptoms in definite degrees of intensity is characteristic of a particular disease. ”

“ By his eminent labours in cellular pathology, Virchow, and Metchnikoff later, gave the last blow to the mere humoral pathology which, after an almost unchallenged prevalence for some two thousand years, now finds a resting-place only in our nurseries. Now the cellular pathology of the blood, investigated by the aid of modern staining methods, is as important as that of the solid organs; no clinical investigator—indeed, apart from research, no practitioner at this day—can dispense with examination of the blood for purposes of diagnosis ”

“ Again, we can most of us remember using very imperfect physiological knowledge to fix, more or less successfully, the locality of an organic lesion in the brain. I also remember such attempts being described as a mere scientific game, which could only be won after the player was beaten, since when the accuracy of diagnosis was established, its object was already lost; but who would say this now, when purely physiological research and purely diagnostic success have led to one of the most brilliant achievements of practical Medicine, the operative treatment of organic diseases of the brain? ”

“ Considerable uncertainty sometimes remains even after the most careful analysis of a case, and often, after stating the first and second diagnoses quite positively, scientific caution and due regard for truth compel us to state the third diagnosis in alternative propositions or as a diagnosis of probability, to be finally settled by the appearance of new symptoms, or in some rare cases only by a post-mortem examination. ”

“ At the beginning of the nineteenth century a young medical practitioner, working faithfully in the wards of his hospital in Paris, pitying especially the patients who suffered from pulmonary disease, and realizing how hopeless was their treatment, since medical science knew so little of the real nature of the ailment from which they suffered, invented the stethoscope and established the principles on which modern physical diagnosis is based in a method so complete that after the lapse of three-quarters of a century very little has been added to what was then discovered. ”

“ The correct use of the foregoing table depends entirely upon correct diagnosis. Knowledge of the vertebra to be adjusted for the correction of any disease is useless unless the disease be recognized when met. Diagnosis may be, and usually is, aided by Palpation and Nerve-Tracing, which may be considered as divisions of diagnosis since the subluxation and the tender nerve are evidences (symptoms) of disease. But these two divisions can never wholly take the place of a complete diagnosis which calls to the aid of the examiner every harmless method of ascertaining the patient’s condition. ”

“ The final diagnosis is with respect to the nature of the lesion. While the second diagnosis may be said to possess the greater scientific interest, this one must be admitted to possess paramount practical importance, as from it we derive the indications for rational treatment and the data of prognosis. The third diagnosis is to be made by the application of the observer's knowledge of general pathology and etiology; hence it is in this field that the best-trained physician succeeds—where the experienced practitioner may sometimes eclipse the brilliant specialist. ”

“ From this time, though he contributed occasional papers, lectures, and cases of value to the Dublin Journal of Medical Science, and to the medical societies, he published no book till 1854, when a valuable treatise [Pg 190] on Diseases of the Heart confirmed his reputation. In this he paid great attention to functional disturbances of the heart, where no organic disease was present. He says with great modesty, “the diagnosis of the combinations of diseases, even in so small an organ as the heart, is still to be worked out.... ”

“ A positive Wassermann reaction in the spinal fluid, the presence of an increase [302] in the albumen and globulin content, with a marked lymphocytosis in the cerebrospinal fluid and a positive gold test, is quite sufficient evidence on which to base a definite diagnosis. The results of an examination of the spinal fluid for diagnostic purposes at the time of autopsy are highly unreliable. An increase in the cell count, which may be misleading, is found in the spinal fluid of non-paretics in all cases after death. The number of cells depends entirely on the time of examination. ”

“ Pathologic material is examined in the fresh state when it is desired to make a diagnosis in the shortest time possible, or when the processes of fixation and hardening produce such alterations in the morphology and chemic constitution of the cells that these features can be recognized only in the unfixed, fresh state. ”

“ The accuracy of diagnosis is not dependent on the content of the case or mastery of the case but may be dependent on approach. This interplay dependent on the content of the case or mastery of the case but may be dependent on approach. Tools that measure these heuristics are yet to be developed; however, the importance of involving patients in their management cannot be overemphasized especially if they are involved from a cognitive point of view in the diagnostic process. There should be an emphasis on improving heuristic strategies. ”

“ The number of offspring in a family is usually too small to serve as a sample of the germ-plasm of the parents. (2) Therefore, since recourse must be had to many families for sufficient data, it is essential that the diagnosis of the defects of the parents and of the children is correct. A single mistake may throw the result into confusion. In cases where the defect is structural, a correct classification may be possible, but in other cases, especially where psychological defects are involved, the diagnosis is difficult and the results, in consequence, less certain. ”

“ On the one hand, a physiologist is bound to accept that the disease was originally developed as a consequence of an anatomical alteration of a certain organ or nerve-cell or fibre; and on the other he is bound to consider that the same disease or consequence develops itself in a young one which has no such circumstances of anatomical alteration of a certain organ or nerve-cell or fibre—at least detectable by any means of investigation at present employed. ”

“ Diagnosis in the early stages of disease "offers the best chance of cure," Major Callender said, but early and accurate diagnosis is not possible in the absence of opportunity to observe enough cases to form a basis for reasonable judgments. Except at large medical centers, there were too few cases of any one kind to afford such opportunity for study. By combining cases from the country as a whole, Major Callender observed, "It will be possible to obtain considerable numbers of cases and specimens in a much shorter time." ”

“ With a degree of practical knowledge of auscultation and percussion sufficient to recognize the signs of inflammatory and structural diseases, and self-confidence sufficient to decide upon the absence of these signs, there is but little liability to error in the diagnosis of functional disorders. ”