PREFACE This course is based on the premise that you are a healthcare professional and that you already understand physiology but want a crash course in pathophysiology or the study of disease states. The study of pathophysiology recognizes that there are normal homeostatic mechanisms in place in the healthy person that drive health and defend against disease. For a variety of reasons—from genetic disorders, to stress or wear-andtear on the system, to patient behaviors—there are things that throw off these homeostatic mechanisms, creating an environment where the normal compensatory activities in place that defend against aberrations in the human body are driven off course. The end result is the creation of diseases you will learn about as part of this course. The first chapter in the course introduces pathophysiology by identifying some of the many genetic diseases involving humans. As you know, there are 23 pairs of human chromosomes with an estimated 19,000-20,000 human protein-coding genes. The estimate of the number of human genes has been repeatedly revised down from initial predictions of 100,000 or more. Genetic disease can be chromosomal, autosomal dominant, autosomal recessive, or x-linked recessive. The basis of these and the types of genetic disorders seen in the different categories is covered in this chapter. The focus of chapter two in the course is the immune system and the pathophysiology of immune disorders. This chapter talks about inflammation and infection, which are two different but interrelated dysfunctions of the immune system. In addition, there are individuals who have immunodeficiency states, which can be primary or acquired, as is the case with human immunodeficiency virus or HIV disease and when individuals receive immunosuppressants after a transplant. Finally, there can be overactivity of the immune system with autoimmune disorders that involve action of the immune system against the individual’s own cells or cell components. Chapter three in the course focuses on the pathophysiology of the diseases of the nervous system. This includes diseases of the brain, including delirium, dementia,
1
