Patient Care in Imaging Technology-- Ch. 4
|Antimicrobial drugs||Drugs that tend to destroy mirobes or prevent their multiplication.|
|Antibiotics||Soluble substances derived from a mold or bacterium that kills or inhibits growth of other microorganisms|
|Arthropod vector||In the family arthropoda that includes spiders, mites, ticks, mosquitoes, etc. can transmit infection to man or animals|
|Attenuated vaccine||A weakened or dilute solution of microbes|
|Bacteria|| Colorless, minute, one-celled organisms with a typical nucleus|
Contain both RNA and DNa
|Broad-spectrum antimicrobial drug||A drug effective against a wide variety of different microorganisms|
|Carrier||A person or animal that harbors a particular infectious agent and does not have clinical disease but is able to transmit the disease to others|
|Cilia||Mobile extensions of a cell surface (look like tiny hairs)|
|Cytomegalovirus infections||A group of viruses in the Herpesviridae family|
|Encephalopathy||A disorder of the brain|
|Enterotoxigenic||Referring to an organism that produces toxins specific for cells in the intestinal tract.|
|Fecal-oral route||Disease passed from one person who has poor hand-washing hygiene to another through food touched by that person following stool elimination.|
|Fungi|| Cells that require an oxygenated environment to live; |
may be either yeasts or molds.
|Genetic predisposition||Inherited potential via the genetic transmission for a particular illness or characteristic|
|Helminths||Parasitic worms that may live in the human intestinal tract for long periods of time if not treated.|
|Immune||Free from acquiring a particular infectious disease|
|Immune suppressed||Persons whose immunity is prohibited for physiologic reasons|
|Infectious disease||A disease capable of being passed from one person to another|
|Nucleoid|| A part of a nucleous (a nuclear inclusion body)|
The part of a bacterium or virus that contains nucleic acid
|Parasite||An organism that lives in or on another and draws its nourishment from that on which it lives. Parasites may be animals or plants (mistletoe)|
|Pathogenicity (pathogen)||The ability to cause disease|
|Percutaneous injection||Passage thru the skin by needle puncture including introduction of wires and catheters|
|Prion|| An infectious particle of nonnucleic acid composition; must mutate to become infectious|
A protein that does not contain DNA or RNA. These are present in the brain and must mutate and become infectious.
May be present by genetic predisposition or the result of infection.
|Transmissable spongiform encephalopathies (TSE)|| Caused by mutant prions|
Ex: Creutzfeldt-Jakob disease or Mad Cow disease which is trasmitted to humans by eating infected meat or meat products.
Care must be taken during pt autopsy as these mutant prior survive fixation with formalin and embedding in paraffin.
|Protozoa||One-celled organisms; often parasitic and are able to move by pseudopod formation, by the action of flagella , or by cilia|
|Pseudopod||A temporary projection of the cytoplasm of certain cells or of certain unicellular organisms, that serves in locomotion and phagocytosis|
|Retension urinary catheters||Tubes that are placed in the urinary bladder and fixed in place for a period of time.|
|Sterile||Free of all living microorganisms|
|Vascular access devices (VAD)||Catheters or needles that are able to enter thte blood vessels|
|Viruses|| Minute microbes that cannot be visualized under an ordinary microscope;|
The smallest microorganism know to produce disease.
|Nosocomial infections||Infections acquired in the course of medical care|
Term most often applied to infections contracted in an acute care hospital but also applies to infections contracted in extended care facilities (nursing homes) outpatient clinics, and behavioral health institutions.
May also be infections contracted at birth by infants of infected mothers.
May not have symptoms of illness until leaving the health care setting but is still considered a nosocomial infection.
|Latrogenic infection||Nasocomial infection that results from a particular treatment or therapeutic procedure.|
|Community-aquired infection||An infection contracted outside of a health care setting or an infection present on admission to the health care facility|
|Everyone has microorganisms in their bodies at all times? True or False|| True|
These microorganisms are our normal flora
|Exogenous nosocomial infection||Infections that are caused by microorganisms that are not normal flora.|
|Endogenous nosocomial infection||An infection in the health care setting as a result of an overgrowth of normal flora.|
Often is the result of alteration of the number of normal flora present in the body or placement of normal flora in another body cavity. ie: normal flora in the GI tract can cause a bladder infection.
May also result from treatment with broad-spectrum antimicrobial drugs that alter the number of normal flora that protect us.
|Factors that encourage nosocomial infections||1. Environment: Contaminated air, people with infections, visitors, contaminated food or instruments, hospital staff|
2. Therapeutic regimen: Immunosuppressive or cytotoxic drugs used for cancer, antimicrobial therapy which may alter the normal flora and encourage growth of resistant strains of microbes.
3. Equipment--contaminated instruments, catheter, IV tubing, cannulas, respiratory therapy equipment, GI tubes
4. Contamination during medical procedures: Microbes transmitted during dressing changes, catheter insertion, or any invasive procedure.
|Factors that increase the potential for nosocomial infections||1. Age: Either the very young (immature immune systems) or the elderly (less efficient immune systems)|
2. Heredity: Congenital or genetic factors may make one more susseptible
3. Nutritional status: Inadequate nutrition, obesity or malnourishment increases risk
4. Stress: Work related or other stress increase potential for infection as levels of cortisone in the body increase related to constant tension
5. Inadequate rest and exercise: Efficient elimination and circulation decline as a result of inadequeate rest and exercise
6. Person habits: Smoking, excessive use of drugs and alcohol an dangerous sexual practices contribute to lower body defenses against nosocomial infection
7. Health history: Diabetes, heart dz, or chronic lung dz, or children not immunized against childhood diseases
8. Inadequate defenses: Broken skin, burn or trauma or immunocompromised persons
|The bloodstream and urinary tract are common sites of nosocomial infections often due to the long-term use of|| Vascular access devices|
Retension urinary catheters
|Infectious diseases are caused by||Microorganisms|
|Protista Kingdom (microorganisms that are not in the animal or plant kingdom) includes|| Bacteria|
|The four major groups of microorganisms that are known to produce diseases are|| Bacteria|
|A microorganism that is known to produce disease is called a||Pathogenic microorganism or pathogen|
|Microorganisms can be useful and not harmful. True or False||True|
| Certain strains of a microorganism which is normally in the body can cause infection. |
True or False
Eshcherichia coli (E coli) is normally found in the GI tract. Howerver there are certain strains of E coli (enterotoxigenic) that may cause a severe cholera-like disease. Probably d/t contaminated beef or water.
|List the sterile areas of the human body|| Brain|
| It is the quantity of microorganisms in an area that produces infection. |
True or False
If the number increases, it may produce infection.
| Some microorganisms are more virulent than others.|
True or False
Some microbes are more certain than others to cause disease if they enter the body.
|Resident flora|| Microbes that live in or on the body at all times in a quantity that is usually stable.|
If the number increases, the flora may become pathogenic.
i.e. staphylococcus on the skin
|Transient flora|| Flora that is acquired by contact with an object on which the flora is present.|
Usually not firmly adherent so can be removed more easily.
|DNA||Carries the inherited characteristics of a cell.|
|RNA||Constructs cell protein in response to the direction of DNA|
| Bacteria are classified according to their shape.|
True or False
Pleomorphic: lacking a definitive shape
|Diplococci means||Group of two|
| Bacteria must be stained to be seen under a microscope.|
True or False
They react to various staining processes
Gram positive means they take up the stain
Gram negative means they do not take up the stain
Acid-fast means they are resistant to colorization by acid alcohol
|Bacteria may be classified in these 3 ways|| 1. Shape|
2. Reaction to staining
3. Immunologice or genetic characteristics
|Typhus and Rocky Mountain Spotted Fever are caused by||Rickettsias (a gram neg bacteria-like microbe that is smaller than bacteria.|
|What is a Spore?|| A protective coat formed by bacteria for survival in an unfavorable condition.|
Bacterial spores are called Endospores.
|Endospores|| Protect the genetic material in a cell. |
When conditions are more stable, the endospore germinate and the bacterial cell begins to grow and replicate.
Endospores are more difficult to destroy
|Aerobes||A bacteria that survives and thrives only in an oxygen environment.|
|Anaerobes||A bacteria that survives and thrives only in an the absence of oxygen.|
|Opportunistics||A bacteria that learns to adapt or thrive in any condition, including the presence of antimicrobial drugs.|
|Yeast (a fungi) reproduces by||Budding (asexual reproduction)|
|Molds (a fungi AKA mycelia) reproduces by||Spore formation (spores float to new surface to grow)|
| Yeasts and molds are always harmful and cause infections?|
True or False
| False. |
They are the primary source of material used to create antibiotics. They produce enzymes for food production to flavor cheese, to produce beer, wine and to leaven bread (bread rises)
Are a source of vitamins and minerals
An example of a yeast dz is candida albicans (thrush)
|A large number of parasites produce disease and these are classified as|| Protozoa--more complex one-cell organisms|
|Protozoa use this method of movement|| Pseudopod|
An action in which a part of the cell is pressed forward and the rest of the cell rapidly follows (snail-like), using flagella (whip-like projections) and celia (hair-like projections on the exterior of the cell wall)
|Helminths can be classified into these 2 groups|| Platyhelminthes (flatworms)|
|Common diseases caused by helminths are|| 1. enterobiasis or pinworm|
3. Diphyllobothrium latum or tapeworm
| Viruses are minute microorganisms that cannot be visualized under an ordinary microscope.|
True or False
Viruses are the smallest microorganisms known to produce disease in humans
|The genetic material of a virus is either DNA or RNA, but never both||True|
|What is a virion?||A complete infectious particle with a central nucleoid, with the genetic material protected by a capsid or protein coat.|
|What is the capsomeres?||The capsid or protein coat made up of minute protein units that protect the genetic material of the virion.|
| Viruses must invade a host cell in order to survive and reproduce?|
True or False
|How does a virus get into the cell and reproduce?||1. The virus attaches itself to a membrane receptor site for which it is specific to the host cell.|
2.Once in the cell, reproduction is not certain as other factors in the cell environment must be favorable.
3. To repoduce, the virus uses the genetic machinery of the host cell.
4. When reproduction is complete, new viruses leave the original host cell.
5. As these viruses leave, some may destro the cell by rapid release of new viruses. This is called lysis.
6. The viruses that do not leave the cell, lay dormant and destructive in the cell.
|Explain how herpes viruses affect the nerve ganglia||1. Some viruses invade the nerve ganglia and leave their genetic material in the ganglia during a latent phase after an acute infective period. |
2. The virus remains there until some type of stress such as an emotional life event or illness or extended exposure to sunlight.
3. The virus is reactivated and takes over nerby cells and produces more viruses.
4. Ex: Varicella virus (chickenpox) can be reactivated as herpes zoster (shingles)
5. This can occur repeatedly.
| Viruses are capable of infecting plants, animals and humans.|
True or False
Some common viral diseases in humans: HIV (AIDS), hepatitis A, B, C, D and E
| A prion is a protein that does not contain DNA or RNA.|
True or False
Like microorganisms, there are a number of prions in brain cells that prevent neurologic disease
|Mutant prion|| Prions can mutate and become an infectious disease. |
This mutation can occur d/t genetic predisposition or may be the result of an infection, which is acquired from an infected animal.
|The 5 elements needed to transmit infection||1. An infectious agent (bacterium, fungus, virus, prior or parasite) and a reservoir of available organisms|
2. A reservoir ( human, animal, plant, etc) or environment (food, earth, etc) in which the pathogenic microbes can live and multiply
3. A portal of exit from the reservoir. This could be the nose, mouth, open wound, intestines, etc.
4. A means of transmission (direct or indirect contact, droplets, by vehicle, by vector or by airborn route).
5. A portal of entry into a new host, by ingestion, inhalation, injection, across mucous membranes or across the placenta.
|List the four characteristics that vary in the ability of an agent to cause disease|| 1. Pathogenicity: The organism's ability to cause disease|
2. Virulence: The organism's ability to grow and multiply with speed.
3. Invasiveness: The organism's ability to enter tissues
4. Specificity: The organism's attraction to a particular host.
| A human host can be any susceptible person.|
True or False
Those at greater risk are those who are immune-suppressed.
| Previous infection with a particular disease or vaccination against a particular disease can render an individual immune to infection.|
True or False
| People living in a poor environment are more likely to contact some diseases owing to poor hygenic conditions and poor diets.|
True or False
| Some diseases have a stong hereditary aspect which maked them more likely to occur in particular races or families who are genetic carriers of the disease.|
True or False
|Antigens are||Foreign or unrecognizable organic substances that invade the body and induce it to produce antibody production|
|Antibodies are|| A protein substance produced by a particular white blood cell, the lymphocyte, or more specifically the B cell. |
B cells work with other lymphocytes called T cells, macrophages, and neutrophils to destroy invading antigens
| All antibodies are immunoglobulins (Ig)|
True or False
|All immunoglobulins (Ig) are antibodies||False|
| Antibodies can also be found in human tears, slaiva and colostrum.|
True or False
|What is Acquired Immunity?||Results from active production (developed after exposure to the infectious agent) or receipt of antibodies|
|What is Active Acquired Immunity?||Antibodies actually produced within a person's body; usually a long-term immunity|
|What is Passive Acquired Immunity?||Anitbodies are received from another person or an animal; usually short-term immunity|
|What is Natural Active Acquired Immunity?||Antibodies acquired by actually having a particular disease, re-infection may be short or long-term|
|What is Artificial Active Acquired Immunity?||Antibodies formed by vaccination that enables the formation of antibodies against that particular antigen|
|What is Passive Acquired Immunity?||Antibodies formed in one individual are transferred to another to protect against infection|
|What is Natural Acquired Immunity?||Antibodies present in a mother's blood or colostrum are passed on the infant to temporarily protect from some infections.|
|Artificial Passive Acquired Immunity?|| Antibodies are transferred from an immune individual to susceptible individual to give temporary immunity. |
Usually done by administration of serum globulin from the blood of immune person(s)
| Vaccines can be made from living or dead (inactivated) microorganisms.|
True or False
Vaccines can also be made from inactivated, nontoxic exotoxin of a pathogenic microbe. This is called a toxoid vaccine.
| Sometimes antibodies function as antigens and produce diseases called autoimmune disease. |
Some examples are:
|Rheumatoid arthritis, systemic lupus erythematosus, and multple sclerosis.|
|Stages and process of infection||1. Incubation stage: Pathogen enters the body and may lie dormant for a short period then begins to produce nonspecific symptoms of the disease|
2. Prodromal stage: More specific symptoms of the particular disease are exhibited. The mocroorganisms increase, and the disease becomes highly infectious.
3. Full disease stage: The disease reaches its fullest extnt or, in some cases, produces only vague, subclinical symptoms; however the disease continues to be highly infectious.
4. Convalescent stage: The symptoms diminish and eventulally disappear. Some diseases disapperar, but the microbe tht caused th disease goes into a lantent phase.
Ex: Malaria, TB, and herpes infections
| Aberrations in chromosal makeup may play a role in influencing the course of hereditary diseases.|
Examples of these diseases are
|Hemophilia, diabetes mellitus, sickle cell disease, and congenital heart anomalies|
|Monogenic disease means||Mutations of one gene that produces disease.|
|A person who can not adequately defend itself against disease is immunodepressed or immunocompromised. This can result from||Malnutrition, may result from medical treatment (chemotherapy, steroids), disease, injury, unknown causes, or present at birth.|
| Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) are critical health conditions that have a huge impact on health care workers. |
True or False
HIV usually results in AIDS, a disease that is currently incurable and has a high mortality rate.
|What is a retrovirus?||A virus tht converts its viral material from RNA to DNA after it penetrates the host cell. They have an enzyme (reverse transcriptinase) which boosts their ability to replicate and infect other cells.|
|What is the cell affected by HIV/AIDS?||T4 lymphocytes|
|List the 5 phases of HIV infection||1. HIV enters the body and replicates in the bloodstream. It can be transmitted at this phase even though there are no symptoms and is not present on lab tests|
2. Symptoms begin: flu-like, lymph nodes may enlarge, fever, skin rash, malaise (vague feeling of discomfort, illness). May have a stiff neck and seizures. HIV can be diagnosed during this phase. The disease can be transmitted.
3. No external smptoms of HIV are present on an average of 110 years. The immune function of the body is declining and T lymphocytes (CD4 cells) are decreasing.
4. HIV infection causes persistently enlarged lymph nodes, low-grade fevers, night sweats, mouth lesions, weight loss, rashes, fatigue, changes in cognition and peripheral neuropathy.
5.Now officicially immunosuppressed and meets the definition of AIDS per the CDC (Center of Disease Control).
CD$ T-lymphocyte count of <200 cells/cumm. The person has oportunistic infections (viral, protozoal, and bacterial) and possibly cancer. 80-90% with AIDS diagnosis die within 3 years.
|What are some complications commonly seen with AIDS?|| 1. Pneumocystis carinii--A type of pneumonia .|
3. Candida (yeast infection)
4. Herpes simplex (cold sores)
5. Kaposi's sarcoma (a malignant tumor of the endothelium)
6. AIDS dementia complex
|Treatment of HIV/AIDS infections|| Goal is to reduce the viral load in the blood stream.|
Begin treatment when CD4/lymphocyte count is less than 200cell/u/l or D4+ percentage is less than 14.
|Components of HIV/AIDS treatment|| 1. Prevention of transmission|
2. Prophylasis against opportunistic infections, especially cytomegalovirus (CMV), neumocystic disease (PCP), and mycobacterium (MAC)
3.. Early diagnosis and treatment of opportunistic infection
4. Good MD-patient relationship
5. Patient education
|Education regarding HIV/AIDS||1. Don't be lax in precautions as it is still a dangerous disease.|
2. Avoid sexual contact with high-risk persons (prostitutes, persons who have multiple sex partners, IV drug users)
3. Follow safe sex practices--use condoms
4. Health care workers must always practice Standard Precautions and be cautious handling needles and other items that may puncture the skin.
5. Maintain good nutritional practices
6. Get adequate amounts of rest and sleep.
|What should a health care worker do if accidentally exposed to HIV while working with a patient with HIV/AIDS?||Report the incident to the supervisor immediately.|
| Viral hepatitis is an inflammation of the cells of the liver and is initially acute but in some cases, may continue to a condition of being a chronic carrier of the disease.|
True or false
It may be caused by 5 separate RNA viruses:
Hepatitis A virus (HVA)
Hepatitis B virus (HVB)
Hepatitis C virus (HVC)
Hepatitis D virus (HVD)
Hepatitis E virus (HVE)
Hepatitis G virus (HVG)
|Hepatitis A and E are transmitted by which route?||Fecal-oral route|
|Hepatitis B, C, D, and G are transmitted by which route?||Blood or body fluid contacts|
|Health care workers most commonly contract which form of hepatitis?||Hepatitis B from needle sticks|
|Persons who share contaminated needles or have multiple sex partners and hemopheliacs are most susceptible to which Hepatitis?||Hepatitis B and C|
|What is the most common form of blood borne infection in the US?|| Hepatitis C|
This used to be called hapatitis non-A, non-B
Often become chronic carriers and at risk of developing chronic liver disease, cirrhosis or liver cancer.
|Symptoms of viral hepatitis|| 1. Sudden symptoms ranging from mild to severe.|
2. Flu-like symptoms with low-grade fever, muscle aches, fatigue
3. After 1-2 wks, jaundice
4. As the disease progresses, the liver enlarges and liver cells die.
|HVB, HVC and HVD can cause chronic hepatitis.|| If inflammation does not resolve (and liver repairs itself), the desease becomes chronic. |
Cirrhosis of the liver, a spontaneous relapse or severe fulminating hepatitis resulting in rapid cell destruction, no regeneration and encephalopathy may occur.
The outcome may be fatal.
| There are vaccines for prevention of all types of hepatitis.|
True or False
There are only vaccinations for hepatitis A and B.
| The incidence of HVC has reduced by meticulous screening of blood doners and blood donations. |
True or False
There are antiviral agents that are of use in treating HVC.
|Tuberculosis is a recurrent, chronic disease caused by the spore-forming ......||Mycobacterium tuberculosis|
|TB most commonly affects what body parts?||The lungs, but is capable of infecting any part of the body.|
|TB is on the rise in the US because?|| 1. Increasing immigrant populaton from third-world countries into the US|
2. Increase of HIV in the US with increase in HIV associated TB.
|Symptoms of pulmonary TB||1. May initially be asymptomatic and go unnoticed. |
2. Early stage sypmptoms are fatigue, loss of appetite, weight loss, and fever that occurs late in teh day
3. Later symptoms are a shallow cough and heyoptysis (coughing up blood sputum).
4. Advancing disease symptoms are wheezes, rales, tracheal deviation and pleuritic chest pain
|Treatment for TB|| TB is treatable if diagnosed and treated early.|
Use of anti-infective drugs--there ae now an increasing number of drug-resistant bacilli.
| Healthcare workers who mus come in contact with patients with active TB must be fitted with a particular respirator mask. |
True or False
The health care worker should know that TB consists of infectious, airborne bacilli to which he may be exposed.
|Annual TB testing is required for all health care workers using this test.|| PPD skin test to detect the possibe exposure to infected persons.|
If the PPD test is positive, a chest Xray will be done and prophylactic treatment started.
|Methicillin-resistant Staphylococcus aureus (MRSA)||Staph aureus used to be treated with penicillin until it became resistant to it. Then methicillin worked for a while but it has not become resistant to that drug.|
Staph is on all our skin. We must take care to not spread the bacteria
Most susceptible to MRSA are debilitated patients, intensive care patients, nursing home patients, dialysis patients, long-time hospitalized patients.
MRSA can cause decubitus ulcers, pneumonia, endocarditis, bacteremia, osteomyelitis, and septic thrombophlebitis.
|Vancomycin-resistant Staphy aureeus (VRSA)||Vancomycin was used for MRSA, but it is feared staph aureus will become resistant to this drug.|
|Vancomycin-resistant Enterococcus (VRE)||Enterococcus is normal flora of the GI tract but can cause disease when it affects blood, urine, or wounds. |
It reproduces in large numbers and is resistant to many antibiotics.
It is resistant to normal handwashing procedures and adheres to objects in the heath care environment.
VRE is thought to be the 2nd most cause for nosocomial infections
|Bacteremia and fungemia|| Bacteremia results from bacteria in the bloodstream. |
Fungemia resulst from fungi in the bloodstream.
Usually results from microbes entering the blood by way of vascular acess devices (VAD).
|Clostridium difficile||Most hospitalized patients are on antibiotics which predisposes them to infections with C difficile by disrupting the normal flora in the GI tract. |
C dificile is a frequent cause of nosocomial infections.
C dificile is a spore-forming bacteria that releases toxins into the bowel that are resistant to disinfectants and therefore can easily spread from hands of healthcare workers.
C. dificile causes pseudomembranous colitis and can produce sepsis.
|Extended spectrum beta-lactamase (ESBL)||Beta-lactamase is a type of enzyme produced by some bacteria that is responsible for their resistance to beta-lactam antibiotics like penicillins, cephalosporins, cephamycins, and carbapenems. |
E. coli and many gram-negative bacteria are resistant to treatment by most antibiotics that are the result of ESBLs.