General Part

Chapter 1

INTERNAL MEDICINE: SUBJECT MATTER, PURPOSE AND OBJECTIVES

General Concepts

Internal medicine encompasses the majority of human diseases and is the most important area of practical medicine. This is the science of diseases of the internal organs and the entire body.

S. P. Botkin, the great Russian physician and scientist, defined the ob­jectives of practical medicine as follows: " The most important and essen­tial objectives of practical medicine are the prevention and treatment of disease, and the alleviation of the patient's suffering". Once we assume that the first objective of a physician is to reveal disease, we must then define what a disease is. What causes a disease, and what is actually a disease? What must we investigate and learn? We all know in general terms what a disease is, but this does not mean that the disease has been understood. The general concept of disease, its essence and genesis, have undergone significant changes during the progress of medicine; and the purpose and objectives of diagnosis have changed accordingly.

Health and disease are opposite yet interdependent forms of the organism's functioning in the physical and social environment. Health is defined by (a) the integrity of the organism (in the broad sense this word implies anatomical and functional integrity, and the absence of injury), (b) sufficient adaptability by the body to the environment; quantitative objec­tive characteristics are very important in this respect. Just as disease may have various degrees of severity, so health can also be weak or strong, and it is determined by the reserves in the body's organs and systems, accurate functional regulation, homeostasis, etc. (interdependence of the body and the environment is the basis of their integrity); and (c) good disposition (this is a subjective criterion, since e.g. euphoria does not rule out pathology).

What then is a disease? Disease is not only an anatomical or functional disorder caused by a pathogenic or an extraordinary stimulus; neither is it their total; it is rather a whole set of changes which arise from affections. Changes in the body in response to stimuli or damage are considered as a

General Part

Chapter 1. Internal Medicine: Subject Matter, Purpose and Objectives

response or reaction. This is manifested by functional and morphological processes. But a disease in its pure form, where one can easily differentiate between a damage and the response to it, occurs infrequently, e.g. an in­jury, an acute infection, etc. A clinicist who treats patients, especially those with chronic diseases, observes a complex of secondary, tertiary and other phases and stages of the damage and the response of the body to this damage.

The first essential sign of a disease is damage caused to the organism (damage to its integrity, its " breakdown", structural damage, functional disorder, the absence of enzymes or other biologically active substances, insufficient homeostasis, etc.).

Another important sign of a disease is the body's response to various affections; response to stimuli is one of the fundamental properties of a living body (irritation function). A dead body does not respond to damage. Damage and a response to it are the requisite and sufficient signs for the basic definition of a disease. Disease is a response of the body to its damage. It is understood that the entire body responds to damage: a local affection causes a response in the entire body, since the response is the complicated result of activity of many systems of the living body. Our definition " a disease is a response of the body to its damage" expresses the dialectical contradiction of the development of pathology: two incompati­ble and mutually interconditioned opposite processes (i.e. damage and response) occur simultaneously. It should be noted that the response (or a chain of reactions) in a living organism is mediated. The body does not act directly against the external aetiological factor (physical, chemical, etc.) but it develops a reaction to the damage, to the changes in the structure and the functions of the body itself that are caused by the pathological factor. This response depends both on the perceptive apparatus (receptors) and on the entire regulatory system. This corresponds to the biological law which states: environmental conditions are altered by the body and converted into its internal conditions. In a physiological sense, a stimulus causes changes in tissues (receptors) to induce or inhibit various functions; the quality of the function depends on the basic properties of the tissue or organ (muscle, glandular or nervous tissue, etc.), their functional state at the moment of stimulation, and on the intensity of the stimulus rather than on the character of the stimulus.

In pathology an injury (depending on its character and localization) ac­counts for the response by the tissue, the system, and the entire body. A very complicated chain reaction occurs, including activity of the first, se­cond and third order, involving several systems. Pain, for example, develops in an injured tissue as a result of the action of bradykinins that are formed in the injured tissue, on the corresponding receptors; an mflam-

matory reaction of tissues is connected with the action of mediators pro­duced in the damaged cells. It is well known that body response to damage often eliminates the defect for the survival of the entire body, i.e. the body response is an adaptive reaction. This special property is the result of " ex­perience" of many millions of generations of living organisms. Patients often recover before any therapy. If a person has a history of a certain disease (e.g. measles, smallpox, etc.) his body is protected from repeated infection: it acquires increased specific and non-specific resistance to the pathogenic factor.

But the response to damage cannot always be regarded as an adaptive reaction. These responses can even sometimes be dangerous to the body, e.g. in autoallergy; carcinoma cannot be regarded as an adaptive reaction to the irritating factor that damages the complicated apparatus of the cell.

Our definition of disease explains the initial purpose of diagnosis: iden­tification (and differentiation) of diseases, what is the damage and what is the response to this damage, and what form of adaptation has occurred in each case. Of course, this is only the initial stage of diagnosis; the correct character of the response and the damage must always be determined in order to give appropriate treatment.

Definition of disease is based on the initial and most general signs; these signs are of major importance for us. Needless to say that disease in man is not only a biological but also a social phenomenon; there is not only a somatic but also a psychic suffering.

Our traditional requirements for complete identification of disease (revealing symptomatology, morphological and functional changes in the body, the causes and pathogenesis of the disease) can be defined as generalized concepts of individual diseases or nosological entities. Although there is no unified classification of diseases, one must consider the qualitative differences between them. The existing classification of in­ternal diseases is characterized by the following two signs: aetiology of the disease and the site of affection.

Diseases of definite aetiology are classified by the aetiological principle, e.g. acute and chronic infectious diseases, injuries, etc; in some cases it is necessary to specify the main site of affection, like the syphilis of the liver. Other diseases are differentiated by the affected organs (localization). This is especially so if the aetiology is unclear or not very important from the practical standpoint, e.g. ulcer of the stomach, cirrhosis of the liver, col­itis, or pancreatitis. Pathogenesis rather than the cause is important in cer­tain other diseases since the cause may be unknown, e.g. allergic sensitiza-tion. Finally, there are diseases that are classified by their special anatomical and functional characteristics. These are tumours.

It should be remembered that disease is a general response by the body

General Part

Chapter 1. Internal Medicine: Subject Matter, Purpose and Objectives

which is regulated by the nervous and humoral systems; an affection of an organ is a most pronounced local manifestation of the response of the en­tire body; the special localization of the process depends on the causative factor and on the condition of the body before the affection. In every disease the entire body is involved. For example, the main site of affection in pneumonia is the lungs, but the cardiovascular system and many other organs of the body are involved simultaneously.

Causes of disease. " Our concept of disease is closely connected with its cause, which always depends on the environmental factors affecting the body either directly or through the agency of its close or remote relatives" (Botkin).

The following causes of disease are distinguished: (1) mechanical (clos­ed and open injuries, concussion, etc.); (2) physical (high or low temperature, electric current, light, radiation); (3) chemical (spoiled foods, poisons); (4) biological (microorganisms); (5) psychogenic; (6) genetic (hereditary).

Strong emotions, fear, and frustration disrupt equilibrium of the nor­mal nervous processes (inhibition and excitation) in the cerebral cortex. They change the activity of the subjugated subcortical vegetative centres regulating the function of the internal organs and upset hormone regula­tion. The environmental factors (the word included) can strongly affect the activity of various organs through the agency of the nervous system. In some cases they may cause disease (by disturbing function of the heart, stomach and other organs or causing essential hypertension).

Most diseases develop as a result of the combined action of many fac­tors, such as unfavourable living conditions (inadequate nutrition, fatigue, overstrain, excitation, etc.). They upset the regulatory and protective func­tion of the nervous system to impair the adaptability of the body to the changing environmental conditions. The resistance of the body to harmful factors (infection, poison, etc.) is decreased allowing a disease to develop. Congenital and acquired specific features and properties of the body are important in aetiology of diseases. They weaken body resistance to harm­ful environmental factors. A person with congenital heart disease may develop a grave circulatory insufficiency when physically overstrained. Asthenic persons when weakened by a grave disease or malnutrition are more susceptible to infectious diseases.

A thorough study of causes of weakening of the body in persons af­fected by disease, and especially the causes of spreading of diseases among population, shows that good health largely depends on the environment and the conditions of work and home life, i.e. social factors. Russian medical workers always emphasized the importance of the environment in the development of pathology. According to a prominent Russian clinicist

A. Ostroumov (1844-1908), " the task of a clinical examination is the study of living conditions of man in the environment, his adaptability to the environment, and disorders". Soviet scientists also emphasize that social environment and relations between people are decisive for their health. Due to favourable social conditions in the Soviet Union morbidity among population decreases significantly and medico-prophylactic ac­tivities widely develop. A medical worker must therefore have a profound knowledge of the biological and social principles of medicine.

Sometimes a disease develops suddenly and lasts a comparatively short time. Such diseases are called acute. Chronic diseases are characterized by prolonged course and may exacerbate periodically. The main disease may provoke another, sometimes grave disease to develop. For example ulcerous perforation of the stomach causes an acute inflammation of the peritoneum. Such a new affection is called a complication of the disease. Sometimes, a disease may recur after a patient recovers. This is a relapse. A patient may have more than one disease at a time. A person with a gastric ulcer may have bronchitis. The more severe disease is called the main disease, while the other disease is the concurrent, or concomitant. A person may recover completely or the disease may become chronic; a possible out­come of disease is death of the patient.

Successful treatment of disease becomes only possible with a correct diagnosis (a good diagnostician is a good doctor), and with identification of the cause of the disease, the specific properties of the patient, the course of the disease, and the knowledge of various medical means.

Diagnostics (Gk dia through, gnosis knowledge) is the science of methods by which diseases are identified. It is the branch of medicine deal­ing with methods for the examination of patients in order to identify a disease, determine the patient's condition and prescribe the appropriate treatment and prophylaxis. The term diagnostics also implies examination and observation of the patient by the doctor who makes a conclusion about the disease and the patient's condition. Diagnostics as a science studies anatomical and physiological features of man and his relationships with the environment.

Diagnosis is a concise conclusion by a doctor of the essence of the disease and the patient's condition, expressed in terms of modern medical science. Diagnosis morbi (definition of the disease according to the ac­cepted classification) and diagnosis aegroti (determination of individual characteristics of a given patient) are distinguished. The disease is iden­tified on the basis of the examination of the patient and the study of syrrip-oms of the disease. The result of a diagnostic examination is the diagnosis ^ot the disease.

Diagnostics includes: (1) the study of methods of observation and ex-

General Part

Chapter 1. Internal Medicine: Subject Matter, Purpose and Objectives

amination of the patient (physical and laboratory-instrumental methods); this is the medical diagnostic technique; (2) the study of the diagnostic value of the symptoms of the disease; this is known as semeiology (Gk semeion sign) or symptomatology; and (3) the study of special ways of pondering aimed at identification of the disease— diagnostic methods.

In compliance with the main tenets of the Soviet clinic the following general trends should be followed as precursors of treatment during each diagnostic examination:

1. Disease is a response of the body to damage. Clinical analysis should
therefore include the study of both damage and the response. The adaptive
tendencies of the response should also be determined.

2. The principle of integrity or unity of an organism requires a complete
diagnosis of the disease and the study of the condition of all physiological
systems of the body, and also of the patient's personality.

3. The principle of unity of the organism and the environment is the
basis for aetiological analysis of the relationships between the patient and
the environment, including social factors.

4. The principle of nervism requires the concrete study of the role of the
nervous system (higher nervous activity included) in the development of the
disease.

The main object of a physician is to cure his patient. Recovery in most diseases is either impossible or takes much time unless timely and effective medical aid is given to the patient. Some patients will inevitably die unless urgent treatment is given. Some diseases can be cured by the inner forces of the body, and any recovery is impossible without their active involvement. Hippocrates would say that " Nature will cure most ailments if she is given a chance". A physician only helps Nature. The main object of treatment is therefore to maintain and increase the forces of the patient in his struggle against the disease. Another important principle is to " do no harm" to the patient by inappropriate action, since the patient's health is already im­paired by the disease.

Best results may be attained where the cause of the disease can be removed. For example, a poisoned patient may be given an antidote or the poison may be removed from his body, or the causative agent may be killed by antibiotics or sulpha drugs. This treatment is called casual or aetiological. But the cause is not always known and cannot therefore be removed. The purpose of treatment then is to act on the mechanism of the disease development (pathogenesis), to provide good conditions for the pa­tient's struggle against the harmful effects, to facilitate and improve the function of the affected organs, to strengthen the patient, for example, by improving his diet, leisure, climatic conditions (tuberculosis patients), or by giving digitalis to patients with cardiac insufficiency. This treatment is known as pathogenetic treatment.

Treatment may also be symptomatic by which only some symptoms of the disease are removed. For example, strong pain may be abated by mor­phine, while the cause of the pain or the mechanism of the pathological process in not affected by this treatment. Symptomatic treatment is often given along with aetiological or pathogenetic therapy.

The doctor must treat the patient rather than the disease (M. Mudrov). For example, a tuberculosis patient may need an envigorating therapy and climatic treatment, while another requires surgical intervention. Treatment should therefore always agree with the character and the course of the disease, individual properties of the patient, and the condition of his ner­vous system. Psychotherapeutic action on the patient is also requisite. Outstanding Russian clinicists, such as Mudrov, Botkin, Ostroumov, and Zakharyin, always took into account the psychic factor. They emphasized that the psychic influence of the doctor on the patient is of great therapeutic importance. The task of medical personnel is first to calm the patient, and to remove his fears and anxiety for the outcome of the disease, then to persuade the patient that the outcome will be favourable, and to strengthen his will-power which is necessary for a successful fight against the disease.

From the very start of the treatment, the physician should work out his tactics thoughtfully and do his best to implement his planned therapy. The planned treatment includes out-patient (home) and hospital treatment, adequate care, accurate fulfilment of the doctor's prescriptions, regular ex­amination of the patient's condition and assessment of the effect of the therapy given. The socialist system provides not only free medical aid, but also a paid sick-leave in loss of working capacity. Patients with long­standing and grave diseases are given special pensions, depending on the degree of disability. On recovery, the patient is given recommendations concerning his future employment, work environment, and life. If recovery is incomplete, health resort therapy is prescribed.