Part 26

Diagnosis involves three main directions of inquiry: 1, as to the general bodily state of the patient; 2, morbid changes in particular organs, tissues, or functions; 3, as to what name properly designates the disorder, according to accepted nomenclature.

Pathology can never be out of view in connection with either the theoretical or the practical study of diagnosis. But it is most closely regarded when the last of these questions is before us, since the names of diseases generally have a more or less distinct reference to their pathological nature. Yet clinical observation always suggests the early use of provisional terms for recognized groupings of morbid phenomena; and sometimes these clinical designations remain for a long time in use because of the imperfection of pathology.

We ascertain, in practice, the nature of a given case, first, by considering its symptoms. These are those obvious evidences of deviation from health which the patient himself is aware of, or which the physician readily discerns or elicits by simple inquiry or examination.

Secondly, taking the clue furnished by symptoms, a closer inspection is made, with the intent of finding what is the actual state of important organs, as the heart, lungs, liver, spleen, kidneys, and alimentary canal.

Lastly, when these means fail to remove all obscurity, or when special scientific investigation is practicable, instruments of precision are employed, as the thermometer, sphygmograph, ophthalmoscope, æsthesiometer, or aspirator; or by the microscope and chemical analyses still more minute examination is made into the particulars of the morbid processes present and their results.

We may subdivide diagnosis, then, into: 1, symptomatology; 2, organoscopy or physical diagnosis; 3, instrumental diagnosis.

Symptomatology.

Semeiology (from [Greek: sêmeion], a sign) is a term much in use, with essentially the same meaning as symptomatology, but less conveniently distinctive, since it does not so well indicate the contrast between obvious signs, or symptoms, and those more recondite, obtained by the methods of physical diagnosis.

Signs of disease cannot be recognized as such except by one who is {149} familiar with the appearances, actions, and manifestations which belong to health. Nor can they be understood, so as to infer what they mean, without knowledge of normal physiology on the one hand, and, on the other, of the natural history of diseases. Physiology constitutes the etymological grammar, symptomatology the vocabulary, and diagnosis the syntax of practical medicine. Just as grammatical knowledge will not enable any one to read or speak a language without acquaintance with its words, so clinical observation is necessary to the physician over and above all the knowledge he may have of physiology and pathology. He must learn to know diseases by sight, or at least by personal contact and observation.

Every one has, of course, a general familiarity with the state and actions of his own and other bodies in health, yet a more exact knowledge of the movements of respiration, circulation, secretion, etc., as well as the form, size, and relative location of all the organs of the body, is needed. Physiology and medical anatomy furnish such information. The more thorough this knowledge is appropriated, the better fitted the student is for practical diagnosis. For its application, however, cultivation of all the perceptive powers is very important. Some men have a genius for quick and clear discernment of symptoms and for their interpretation, as well as for that of physical signs. But all can much improve their senses, and their sagacity in using them, by experience. For this, if for no other reason, scientific training, in field or laboratory studies, affords the best introduction to the work of the medical student and physician. The traits most needed for success in diagnosis are exactness and comprehensiveness. First, to be sure precisely what each sign is that comes under observation; next, to overlook no existing symptoms or physical signs; and, last, so to combine them into a mental map, diagram, or picture, as to make a coherent and rational whole. This nosogram may then be compared with the descriptions of standard authorities, to find its place (if it has one) in technical classification. First, however, ascertain the thing, the morbid state or combination of states; afterward the name, or morbid species, when practicable. It is always to be remembered that complication of diseases, or at least the existence of some irregular manifestations along with those which are characteristic, is more common than the occurrence of purely typical cases. The portraits of most diseases in the books are averages, like the composite class-photographs of Douglas Galton. Not nearly every case will correspond with such an average in all respects. Moreover, so great is the possible variety of alterations among the different organs of the body that the chances of two instances of disease being precisely alike in every particular are hardly greater than those in favor of every move being the same in two games of chess with the same opening.

In an essay like the present it is not easy to decide upon the best manner of treating the subject before us. Too much or too little may be said. With advanced readers the whole history of symptoms and physical signs might be left to the special discussions occurring in articles upon different diseases. But it may be taken for granted that those who consult the present work will do so either at a comparatively early stage of their studies or when time has made desirable a renewal of what may have been once known and then forgotten. Since, then, it is impossible {150} to anticipate what may be the exact needs of either class, a somewhat elementary statement of main facts appears justifiable here.

Following the natural method, we may suppose a call to visit a patient. Arriving in his presence, the first question (mostly left out of view and rarely expressed) may be, Is it a case of real or only imaginary indisposition? Army medical officers, more than most others, can appreciate the possibility of this inquiry sometimes disposing of the whole case.

Supposing it to be real, is it an illness or an accident or other injury? Is it severe or of trifling account? Acute or chronic? We observe the position of the patient, lying quietly in bed, sitting up, or walking restlessly about the room. Then the countenance is observed--pale or flushed, tranquil or excited in expression. We feel the forehead, touch the cheek and hand. Is the skin hot or cold, dry or moist? The pulse is felt; the breathing also is counted.

Of the patient himself or of another (in serious acute cases better of his care-taker, in another apartment) we ask questions whose answers give us the general history of the case. When not before known these should include his antecedent personal history, even extending to that of the family, as far as can be learned. What tendencies have they, or has he or she, shown by previous attacks and their results?

So we come to the present attack: When did it begin, and how? What have been its prominent symptoms since? Questions are then to be put concerning the heat of the body, appetite, complaint of pain, sleep, movement of the bowels, discharge of urine: in the female, menstruation; if married, pregnancy or parturition, how often and when occurring last. Thus the practitioner is enabled to get a clue to the diagnosis, to be followed out through his own observation and closer examination. If the patient be a child and the attack be acute and febrile, an early question must be as to its having passed or not through the different diseases of childhood--viz. the exanthemata, mumps, and whooping cough, and also what exposure to any of these it may have been recently subjected to.

Going farther into particulars, let us review some of the possible developments obtained in the above questioning of symptoms.

When lying in bed the decubitus may be significant, as, upon the back with the knees drawn up in peritonitis; with the hands pressing the abdomen in colic; tossing to and fro in the delirium of fever or of early cerebral inflammation; on one side constantly in acute inflammation of the liver or in pleurisy. Or the patient may be obliged to be propped in a sitting posture (orthopnoea) from heart-disease, asthma, or ascites, or leaning forward upon the back of a chair or a pillow with aneurism of the aorta. More remarkable still may be the subsultus tendinum of low fever, the opisthotonos of tetanus, the respiratory spasms of hydrophobia, or the clonic movements of epileptic, hysterical, or occasional convulsions.

In the face we see pallor in syncope and in anæmia in any of its varieties and with varied associations; a general redness in some cases of apoplexy and in remittent fever; flushing of the forehead and eyes especially in yellow fever; dusky redness in typhus, and a more purple hue in typhoid fever; yellowness in jaundice, in some cases of remittent and in most of yellow fever; sallowness in cancer; a bright central glow upon each cheek in early pneumonia or the hectic of phthisis; a blue or ashen appearance in the collapse of cholera, and blackish-blue in {151} cyanosis or carbonic acid poisoning; bronzed in Addison's disease; puffy about the eyelids in Bright's disease; the surface swollen, yet resistant to the touch, in myxoedema. The eyes (one or both) glare prominently in exophthalmic goitre; squint in advanced cerebro-meningitis; roll to and fro often in the prostration of cholera infantum and in convulsions; are clear and bright in phthisis; yellowish in hepatic disorder; dull and clouded in low fevers; without expression in imbecility and general paralysis.

Contraction of the pupil is observed in inflammation of the retina or of the brain, narcotism from opium (until near death) or eserine, or apoplectic effusion near the pons varolii. Dilatation of the pupil is seen in most cases of hydrocephalus and of apoplexy; in nerve-blindness (amaurosis), glaucoma, cataract, and narcotism from atropia, duboisia, or hydrocyanic acid. Inactivity of the pupil (Argyll Robertson) under changes of light and darkness is common in locomotor ataxia. Different states of the two pupils under the same light show disorder, either ophthalmic or cerebral in site, or may indicate pressure on the cervical sympathetic ganglia, as from aortic aneurism.

In elderly persons we ought always to look for the arcus senilis, which is a sign of a tendency to fatty degeneration. It is a ring, or part of a ring, with ill-defined edges, best seen by lifting or depressing an eyelid, at the junction of the cornea and sclerotic coat of the eye. In some quite healthy old persons there may be seen at the same junction a clearly-defined circular line of calcareous nature. This must be distinguished from the true fatty arcus senilis.

Of the face we may also notice the pinched nose, hollow eyes, and falling jaw of the facies Hippocratica, presaging death; the square forehead of the rickety child (not common in this country); ulcers on the forehead, scars at the mouth-corners, or copper-colored eruptions in syphilis; the full, flabby lips of scrofula. In peritonitis or gastritis the mouth is apt to be drawn up with a peculiar expression of suffering and nausea. Very striking is the characteristic one-sided appearance in facial palsy, from lesion of the seventh nerve. There may be a smile, a frown, or other expression on the sound side of the face, while the paralyzed side is quite immovable. As the seventh nerve (portio dura) supplies the orbicularis muscles, its paralysis (so often temporary) may cause inability to close the eye upon the affected side. Ptosis, or inability to open the eye, involving the levator palpebræ, which is innervated by the third nerve (motor oculi) is more significant of cerebral lesion.

Even the ears may have language, as when their lobes are full and glistening red in the gouty diathesis, or wrinkled in prolonged cachexiæ, or when they are running with discharges in the struma (scrofula) of childhood. The hair becomes dry and lustreless in phthisis, and falls out during convalescence from many acute diseases.

If we look at the gums in a case of lead-poisoning, we may expect to find a blue line along their edges. Scurvy is betokened by a swollen, spongy, and easily-bleeding state of the gums. Many scorbutic cases, however, lack this so-called pathognomonic feature. It may be remarked, by the way, that absolutely pathognomonic signs of particular diseases, never absent and exclusively seen in them, are very few. Albuminuria, for example, is not always present in Bright's disease, and is {152} also met with in a number of other affections. Sugar in the urine may follow inhalation of chloroform or an attack of cholera, as well as diabetes mellitus. Rice-water discharges may be absent in the collapse of cholera, and patients may die with yellow fever without black vomit. Still, these symptoms have great diagnostic value, and, taken with others associated with them, may often enable us to attain to a diagnosis of much importance.

Perfect teeth in an adult in this country are rather the exception than the rule. In the notched incisors of inherited syphilis, however, there is something quite distinctive. The notches in Hutchinson's teeth are vertical, not horizontal.

Old as medicine is the examination of the tongue in disease. It may be protruded with difficulty, as in low fevers, in apoplexy, and in cerebral paralysis (bulbar sclerosis, glosso-labio-pharyngeal paralysis) or thrust to one (the paralyzed) side in hemiplegia. It is pallid in anæmia; yellow in bilious disorder; red in glossitis (then swollen also), in scarlet fever, and in gastritis; furred in indigestion, gastro-hepatic catarrh, and the early stage of various febrile attacks; dry, brown, cracked, or fissured in typhus or typhoid fevers and in the typhoid state of malarial remittent fever; bare of epithelium in advancing phthisis and in imperfect convalescence from severe acute diseases. Coldness of the tongue is one of the worst signs in the collapse of cholera.

As we examine the throat internally we look for signs of faucial inflammation in redness and swelling, with or without enlargement of the tonsils, or relaxation and elongation of the uvula, or ulceration, or the gray or brown membranous deposit of diphtheria. In the mouth of a child we may find the little white vesicular patches called aphthæ, the curd-like exudations of thrush, or possibly the much worse grayish ulcerations of cancrum oris, or the rarer ashen sloughs of gangrene of the mouth.

Outside of the throat we must remember the significance of glandular swellings or scars of suppurated glands in children; nor overlook, if present, stiffness of the muscles, or torticollis, or goitrous enlargement of the thyroid gland. Observation should be made also of the site of the carotid artery on each side, and of the jugular veins, since aortic regurgitation may be indicated by violent action of those arteries or tricuspid regurgitation by pulsation of the veins in the neck.

Long before vaso-motor physiology had any place in science the pulse was known to afford valuable indications in disease. Either of the accessible arteries will answer instead of the radial; its convenience merely makes the wrist the common place of comparison. By careful examination of the pulse something may be learned of several of the factors concerned in its production. These factors are--1, the muscular force of the walls of the heart; 2, the state of the cardiac valves; 3, the muscularity of the arteries; 4, the elasticity of the arterial coats; 5, the state of the capillary circulation; 6, the qualities of the blood; 7, the condition of the nervous system as to excitability or apathy.