Introduction to Human Disease Dr. Sue Makin Department of Nursing Hannam University

Disease, Disorder, Syndrome Homeostasis – the state sameness or being normal that the body tried to maintain Disorder – derangement or abnormality of function Syndrome – a group of symptoms, which may be caused by a specific disease, or possible by several interrelated problems Disease – change in structure or function of the body, or any change from normal in the body

Pathology Pathology – the study of disease Pathologist – medical doctor who specialises in studying disease Surgical pathologist – studies or examines surgical tissue or biopsies for evidence of disease Clinical pathologist – supervises a clinical pathology laboratory, including several departments such as hematology, chemistry, microbiology, serology, etc. Medical examiner – studies human tissue to determine the cause of death

Other Definitions Pathogenesis – description of how a disease progresses Acute disease – lasts a short time and usually has a sudden onset Chronic disease – lasts a long time, and may take time to develop Etiology – the study of the cause of a disease Idiopathic – the cause of a disease is unknown Nosocomial – acquired in the hospital Iatrogenic – caused by a prescribed treatment

Predisposing Factors Predisposing factors = risk factors Predisposing factors – make a person more susceptible to disease, not the cause of a disease Predisposing factors include age, sex, environment, lifestyle, and heredity

Diagnosis, Prognosis, Treatment Diagnosis – the identification or naming of a disease. The doctor will try very hard to determine the diagnosis of a problem. Medical history – review of all the information about a patient, including previous illnesses, family illnesses, predisposing factors, current symptoms Prognosis – the predicted or expected outcome or result of the disease o Remission – the symptoms of a disease are less or go away o Exacerbation – the symptoms of a disease become worse Treatment – a plan of care for the patient

Medical Ethics Ethics deals with the rightness or wrongness of actions or plans Medical ethics includes the values and decisions in medical practice Because the choices and decisions available and necessary in our modern world are many, questions about the rightness or wrongness have become common

Causes of Disease Heredity Trauma Inflammation/Infection Hyperplasias/ Neoplasms Nutritional Imbalance Impaired Immunity Aging Death

Hereditary Diseases These diseases are caused by abnormalities in either the genes or the chromosomes of an individual Congenital disease – a disease which is present at birth. Not all congenital diseases are inherited. Examples of congenital disorders that are not inherited include fetal alcohol syndrome, which is caused by the mother’s drinking of alcohol during pregnancy, and cerebral palsy, which may be caused by a difficult delivery

Trauma Disease caused to humans by physical injury from an external force o Motor vehicle accidents o Falls o Drowning o Burns o Poisoning o Physical abuse

Inflammation/Infection Inflammation is a protective response of the body to any type of irritation or injury, not necessarily from a bacteria or virus, but including these as well Infection – invasion of microorganisms into tissue that causes cell or tissue injury

Hyperplasias/Neoplasms Hyperplasia – an overgrowth in cell numbers and in tissue size in response to some type of stimulus Neoplasms, commonly called tumors – refer to “new growths” in the body Neoplasms may be described as benign or malignant o Benign – not deadly o Malignant – tumors that grow uncontrollably and can cause death

Terms You Need to Know Adenoma Carcinoma Fibroma Glioma Lipoma Melanoma Sarcoma See Table 2-2, page16

Nutritional Health Nutrition is important in maintaining good health Nutritional diseases can be due to eating too much or too little Certain diseases may cause a person to be unable to absorb nutrients, even though they may be eating an adequate diet Cachexia – term used to describe any person who has an ill, thin, wasted appearance Total parenteral nutrition – providing the total nutrition needed by gving nutritive liquid through the venous route

Impaired Immunity Immune system of the body – specialized group of cells, tissues, and organs that are designed to defend the body against pathogenic attacks Two basic ways the immune system protects the body o The inflammatory response – leukocytes play a vital part in the killing of foreign invaders o The specific antigen-antibody reaction in which the body responds to antigens, substances foreign to the body. The body’s response to antigens is to produce antibodies.

Aging The process of aging of the human body begins at the age of physical maturity, which is around age 18. The aging process is progressive and not reversible. This means that the process continues all the time, and the body does not go backwards and reverse the aging process. The body replaces and rapairs itself throughout its lifetime, but with aging, this process slows

Death One way to try to understand the aging process is to study cellular, tissue, and organ death Cellular injury can be caused by o Hypoxia, not enough oxygen o Anoxia, no oxygen at all o Drug or bacterial toxins o Viruses

Cellular Adaptation Cells that are exposed to adverse, or damaging, conditions often go through a process of adaptation Types of adaption include o Hypertrophy o Metaplasia o Dysplasia o Neoplasia

Cell and Tissue Death Necrosis – cell death, the death of a cell or a number of cells Infarct – death of cells or tissue due to ischemia Ischemia – hypoxia (lack of oxygen) of cells or tissues due to decreased blood flow

Organism Death Morbidity – state of being diseased Prior to death, major organs such as the heart, lungs, or brain stop functioning. Once the brain stops functioning, the person is considered brain dead. Criteria for brain death o A lack of response to stimuli o Loss of all reflexes o Absence of respirations or breathing effort o Lack of brain activity on an electroencephalogram (EEG)

Machine for electroencephalogram

Electroencephalogram