Introduction to clinical cases

Introduction to clinical cases

• Homeostasis

Any self-regulating process by which a biological or mechanical system maintains stability while adjusting to changing conditions. Systems in dynamic equilibrium reach a balance in which internal change continuously compensates for external change in a feedback control process to keep conditions relatively uniform. An example is temperature regulationmechanically in a room by a thermostat or biologically in the body by a complex system controlled by the hypothalamus, which adjusts breathing and metabolic rates, blood-vessel dilation, and blood-sugar level in response to changes caused by factors including ambient temperature, hormones, and disease.

• Disease

 is a term for any condition that impairs the normal functioning of an organism or body. Although plants and animals also contract diseases, by far the most significant disease-related areas of interest are those conditions that afflict human beings. They can be divided into three categories: intrinsic, or coming from within the body; extrinsic, or emerging from outside it; and of unknown origin. Until the twentieth century brought changes in the living standards and health care of industrialized societies, extrinsic diseases were the greater threat; today, however, diseases of intrinsic origin are much more familiar. Among them are stress-related diseases, autoimmune disorders, cancers, hereditary diseases, glandular conditions, and conditions resulting from malnutrition. There are also illnesses, such as Alzheimer's disease, whose causes remain essentially unknown.

Any condition that impairs the normal functioning of an organism can be called a disease. In the human organism, as in all others, there are certain basic requirements, which in the human body include the need for a certain proper amount of oxygen, acidity, salinity (salt content), nutrients, and so on. These conditions must all be maintained within a very narrow range, and any deviation can bring about disease.

Diseases can be classified into three general groups. There are conditions that are infectious, or extrinsic, meaning that they are caused by an infection through which a virus, bacterium, or other parasite enters the body. Infectious diseases, infections, and the immune system that usually protects us against them are discussed elsewhere in this book. Our attention in the present context will be devoted to the other two broad categories—noninfectious, or intrinsic, diseases and diseases of unknown origin.

There are several basic varieties of intrinsic disease, or conditions that are neither contagious nor communicable. These varieties are listed in the next few paragraphs. The essay Noninfectious Diseases includes a discussion of other systems for classifying diseases of either the intrinsic or the extrinsic variety.

• Causes of diseases

Trying to research the formation process of many diseases doesn't require as much time as we might think. Even though every person's body is as unique as our fingerprints, the general outline of disease process is roughly the same. In simple terms, every health problem, from a simple rush or allergy to cancer on one of our organs, is a disorder of the whole body. Whatever name we give it, its cause is the accumulation of toxins. The toxins come from two sources:

1. From outside with food, air, water, medications, etc.
2. Produced in our body as a result of its own life processes and life processes of bacteria living in it.

Undigested food forms deposits in the large intestine and becomes breeding ground for toxin-producing bacteria. Toxins are absorbed by intestinal walls and blood carries them to all our organs, where they cause diseases. To make the point, I'll use a drastic example of experiments done by the Nazis during the Second World War. They took the contents of the large intestine from prisoners suffering from chronic constipation, made serum from it, and injected healthy prisoners with it. Depending on the amount of serum, the injections resulted in psychological disorders, burst blood vessels, and strokes.