Pharmacology Chapter 8: Anti-Infective Agents
After teaching a group of nursing students about the use of anti-infectives for prophylaxis, the instructor determines that the students need additional teaching when a student identifies what as an example? A) A client with an oral yeast infection who receives antifungal therapy. B) A client who is scheduled for abdominal surgery receives antibiotic therapy. C) A client with a mitral valve replacement receives antibiotics before a tooth extraction. D) A client who receives antimalarial therapy in preparation for travel to Africa.
A) A client with an oral yeast infection who receives antifungal therapy. Explanation: Prophylaxis is the use of anti-infectives to prevent infections before they occur. The use of antifungal agents for an existing yeast infection is treatment, not prophylaxis. Preoperative therapy to prevent a postoperative infection would be an example of prophylaxis. Therapy before a dental procedure is an example of prophylaxis. Use of antimalarials before travel is an example of prophylaxis.
The nurse is caring for several medical clients who have infections. For which client would the administration of a broad spectrum antibiotic be most appropriate? A) A client with signs of infection who is awaiting the results of laboratory testing B) A client with pneumonia who has a confirmed allergy to penicillins C) A client who is being treated for a urinary tract infection for the third time this year D) A client with an infected surgical wound
A) A client with signs of infection who is awaiting the results of laboratory testing Explanation: Broad spectrum antibiotics are effective against a wide variety of microorganisms. None of the other listed clients have obvious indications for using a broad spectrum antibiotic.
Culture and susceptibility tests are performed prior to the prescription of antimicrobial drugs. What is the specific purpose of the culture test? A) Identifies the organism causing the infection B) determines the severity of the infection C) identifies the drugs that might be effective in treatment D) predicts the body's response to the infection
A) Identifies the organism causing the infection Explanation: Culture identifies the infection's causative organism. Susceptibility tests determine which drugs are likely to be effective against the organism.
A nurse is aware that the concept of selective toxicity is foundational to antimicrobial therapy. Which statement most accurately describes selective toxicity? A) A drug harms microbes without harming human cells. B) A drug's effect on microorganisms is proportionate to dose. C) Most microbes may be collected from a host and cultured on an alternative medium. D) A drug can be isolated and produced in a controlled manner in a laboratory setting.
A) A drug harms microbes without harming human cells. Explanation: An important principle of antimicrobial therapy is selective toxicity, which is the ability to suppress or kill an infecting microbe without injury to the host. This concept does not denote dose-dependent effects, the ability to culture a microorganism, or the production of a drug.
For what client would the use of prophylactic anti-infective be most appropriate? A) A pre-surgical client who has an artificial heart valve B) A client who works in a clinic where many ill children are treated C) A client with type 2 diabetes who lives in a crowded home D) A client who uses street drugs intravenously
A) A pre-surgical client who has an artificial heart valve Explanation: A client with valve replacement is especially prone to the development of subacute bacterial endocarditis because of the vulnerability of their heart valves; prophylactic antibiotic therapy as a precaution. None of the other listed clients has particular indications for the use of prophylactic anti-infectives.
After teaching a group of students about adverse reactions to anti-infective agents, the instructor determines that the students need additional teaching when they identify what as a common adverse effect? A) Cardiac toxicity B) Hypersensitivity C) Kidney damage D) Neurotoxicity
A) Cardiac toxicity Explanation: Cardiac toxicity is not typically associated with anti-infective therapy. Adverse effects commonly associated with anti-infective therapy are direct toxic effects on the kidney, gastrointestinal tract, and nervous system along with hypersensitivity and superinfections.
The nurse is caring for a client who is immunocompromised following a kidney transplant and who has developed an infection. When planning this client's care, the nurse should prioritize what action? A) Carefully maintaining the client's isolation precautions B) Educating the client about the need for frequent hand hygiene C) Monitoring the client's liver function closely D) Monitoring the client for gastrointestinal effects of anti-infective therapy
A) Carefully maintaining the client's isolation precautions Explanation: Even though assessment is an important aspect of nursing care, maintenance of infection control measures is a priority due to the safety risk to the client. The client should be taught about hand hygiene, but it is even more important for nurses and family members to maintain hand hygiene.
A nurse is asked to explain the difference between community-acquired infections and hospital-acquired infections. What response best describes the difference? A) Community-acquired infections are usually less severe and easier to treat since hospital-acquired infections often involve drug-resistant microorganisms. B) Hospital-acquired infections are typically less severe and easier to treat because they occur in the presence of trained medical staff.\ C) There is no epidemiological difference between the infection types; they are simply categorized as community-acquired or hospital-acquired. D) Only drug-resistant strains of staphylococci, Pseudomonas, and Proteus are categorized as hospital-acquired infections.
A) Community-acquired infections are usually less severe and easier to treat since hospital-acquired infections often involve drug-resistant microorganisms. Explanation: Infections are often categorized as community-acquired or hospital-acquired. Because the microbial environments differ, the two types of infections often have different causes and require different antimicrobial treatment. Generally, hospital-acquired infections are more severe and difficult to manage because they often result from drug-resistant microorganisms and occur in people whose immunity is impaired. A wide variety of organisms can lead to hospital-acquired infections.
A female client is treated with antibiotics for bacterial pneumonia. When obtaining a drug history, the nurse finds that the client ceased her medication regimen when she no longer experienced symptoms during the first round of antibiotics. The nurse is responsible for the client's education plan. In order to effectively treat the pneumonia, what must the client do? A) Complete a full course of antibiotics as prescribed. B) Continue the antibiotics for 1 week after cessation of symptoms. C) Take the antibiotics at breakfast, lunch, and supper. D) Take the antibiotics every 3 hours during the day.
A) Complete a full course of antibiotics as prescribed. Explanation: Client education related to antibiotic therapy should stress the importance of completing a full course of antibiotics as prescribed.
A client with an inflammatory disease has been prescribed indomethacin. The nurse is aware of the risk for drug-induced nephrotoxicity and should prioritize what intervention? A) Encouraging the client to increase fluid intake B) Educating the client about sodium limitation C) Administering the medication with meals whenever possible D) Monitoring closely for hematuria
A) Encouraging the client to increase fluid intake Explanation: Adequate hydration is important whenever a client is receiving a potentially nephrotoxic drug. Limiting sodium intake and administering drugs with food do not mitigate this risk. Kidney damage most often results in oliguria and changes to urine and blood chemistry, not hematuria.
When participating in the care of a client who is being treated with antimicrobials, the nurse can promote the appropriate use of these medications in which way? A) Encouraging the use of narrow-spectrum, rather than broad-spectrum, antibiotics B) Promoting the use of prophylactic antibiotics for clients possessing risk factors for infection C) Initiating empiric therapy for all older adult clients admitted to a health care facility D) Promoting the use of herbal treatment for infection rather than antimicrobial drugs
A) Encouraging the use of narrow-spectrum, rather than broad-spectrum, antibiotics Explanation: Guidelines to promote more appropriate use of antimicrobial drugs include using a narrow-spectrum antibacterial drug instead of a broad-spectrum drug, whenever possible, in order to decrease the risk of a superinfection. Herbal alternatives are frequently not available. Antibiotics should not normally be administered in the absence of a diagnosed infection.
Which would be tested to determine parasitic sources of infection? A) Blood B) Stool C) Sputum D) Sweat
B) Stool Explanation: When investigators search for parasitic sources of infection, they may examine stool for ova and parasites.
The nurse is caring for an older adult client who is being treated for community-acquired pneumonia. Over the past 12 hours, the client has had three episodes of diarrhea despite having no known history of gastrointestinal disease. What is the nurse's best action? A) Report this sign of a possible superinfection to the provider. B) Obtain a stool sample for ova and parasite testing. C) Obtain a stool sample for culture and sensitivity testing. D) Advocate for a change in the client's medication regimen.
A) Report this sign of a possible superinfection to the provider. Explanation: This client has most likely been receiving antibiotics and the rapid onset of diarrhea is suggestive of a superinfection. The care provider should be informed and then any necessary laboratory testing will be ordered. Interventions will likely be necessary but this may or may not include a change in the client's medication regimen.
The nurse is providing care for an older adult who has a urinary tract infection. What aspect of this client's current health status should the nurse focus on when ensuring safe and effective antibiotic therapy? A) The client has a history of cirrhosis. B) The client has type 2 diabetes controlled with diet. C) The client uses bronchodilators for the treatment of asthma. D) The client had a hip fracture 8 months ago.
A) The client has a history of cirrhosis. Explanation: Cirrhosis causes decreased liver function, which would have a major bearing on medication therapy. Each of the other aspects of the client's history are significant, but none will have as direct an effect as liver disease.
A 30-year-old female client received an insect bite that has progressed to cellulitis over the past several days. What client characteristic should the nurse prioritize when administering anti-infectives? A) The client is in the second trimester of pregnancy. B) The client has known allergies to nonsteroidal anti-inflammatories. C) The client was treated for leukemia when she was a teenager. D) The client admits to using marijuana recreationally.
A) The client is in the second trimester of pregnancy. Explanation: Pregnancy and breastfeeding have major effects on the decision to administer anti-infectives and the choice of medication. An allergy to NSAIDs would not have a significant effect on the administration of anti-infectives. Similarly, marijuana use and a distant history of cancer would not have such as large effect on the choice of medication.
A nurse is teaching a colleague about the factors that are known to contribute to antibiotic resistance. When phenomenon should the nurse describe? A) Use of antibiotics for viral illnesses B) Use of excessive doses during anti-infective therapy C) Over-the-counter availability of some antibiotics in the United States D) Increasing incidence of adverse effects of anti-infectives in recent years
A) Use of antibiotics for viral illnesses Explanation: The use of antibiotics for viral illnesses or infections is a contributing factor to the development of resistance. Antibiotics are not available over the counter in the United States and there has not been a trend toward excessive dosing or increases in adverse effects.
A nurse is taking a history on a client new to the clinic. The client reports being allergic to penicillin. What additional information about this reported allergy would be important for the nurse to find out? A) What reaction symptoms occurred B) What was done to stop the reaction C) Who was the caregiver at the time of the reaction D) What other allergies the client has
A) What reaction symptoms occurred Explanation: It is important to determine what the allergic reaction was and when the client experienced it (e.g., after first use of drug, after years of use). Some clients report having a drug allergy, but closer investigation indicates that their reaction actually constituted an anticipated effect or a known adverse effect to the drug. It would not necessarily be important to find out what was done to stop the reaction, who the caregiver was at the time of the reaction, or what other allergies the client has.
Which client would be at risk of developing an infection? Select all that apply. A) a client with an impaired immune system B) a client who performs daily hygiene care C) a client experiencing diarrhea chronically D) an elderly client who has one chronic disease E) a client who takes nutritional supplements
A) a client with an impaired immune system C) a client experiencing diarrhea chronically D) an elderly client who has one chronic disease Explanation: Many factors impair the host defense mechanisms and predispose a person to infection by disease-producing microorganisms. These include breaks in the skin and mucous membranes, impaired blood supply, neutropenia and other blood disorders, malnutrition, poor personal hygiene, suppression of normal bacterial flora by antimicrobial drugs, diabetes mellitus and other chronic diseases, and advanced age. A client who has chronic diarrhea can experience malnutrition. A client who performs daily care and a client who takes nutritional supplements are not at risk for infection.
Successful treatment with bacteriostatic antibiotics depends upon what factor? A) adequate duration of drug therapy. B) stopping drug therapy when symptoms have subsided. C) using broad-spectrum antibacterial drugs to treat viral infections. D) the type of drug-resistant bacterial strains that can reproduce in the presence of antimicrobial drugs.
A) adequate duration of drug therapy. Explanation: Successful treatment with bacteriostatic antibiotics depends on the ability of the host's immune system to eliminate the inhibited bacteria and an adequate duration of drug therapy. Stopping an antibiotic prematurely can result in rapid resumption of bacterial growth. Antibiotics are not used to treat viral infections.
What are classified as anti-infectives? (Select all that apply.) A) anthelmintics B) antifungals C) antiprotozoals D) anticonvulsants E) antimetabolites
A) anthelmintics B) antifungals C) antiprotozoals Explanation: Anti-infectives include antibiotics, antivirals, antifungals, antiprotozoals, and anthelmintic agents.
A client comes to the clinic reporting mouth sores that appear consistent with an oral yeast infection. The nurse should question the client about recent use of: A) antibiotics. B) oral contraceptive agents. C) antivirals. D) antiprotozoals.
A) antibiotics. Explanation: The client is exhibiting signs of a superinfection, which can occur with the use of antibiotics. Superinfections are not associated with oral contraceptives, multivitamins, or anticoagulants.
An immunocompromised patient in a critical care setting has developed a respiratory infection that has been attributed to methicillin-resistant Staphylococcus aureus (MRSA). The nurse should anticipate that the patient will require treatment with A) ciprofloxacin. B) clindamycin. C) vancomycin. D) an antistaphylococcal penicillin.
C) vancomycin. Explanation: Vancomycin is the drug of choice to manage infections caused by MRSA. MRSA is resistant to all of the antistaphylococcal penicillins, as well as to ciprofloxacin and clindamycin.
A client is febrile and is suspected of having a respiratory infection. A sputum culture has been collected and the results of sensitivity testing are expected within 48 hours. The nurse should anticipate that the client may: A) be immediately prescribed a broad-spectrum antibiotic. B) receive supportive care until an antibiotic can be prescribed in 48 hours. C) be treated with antiviral medication on a short-term basis. D) need to provide a follow-up sputum culture before medications can be prescribed.
A) be immediately prescribed a broad-spectrum antibiotic. Explanation: Broad-spectrum antibiotics are often prescribed pending sensitivity testing. There is no need to completely withhold medications until results are acquired. Antiviral medications are not used for this short-term purpose. Follow-up testing may or may not be needed.
Administration of what type of antibiotic by the nurse would be most likely to cause a superinfection? A) broad spectrum B) narrow spectrum C) bactericidal D) bacteriostatic
A) broad spectrum Explanation: One offshoot of the use of anti-infectives, especially broad-spectrum anti-infectives, is destruction of the normal flora, allowing opportunistic pathogens to invade tissue and cause a superinfection. Narrow-spectrum anti-infectives are less likely to kill normal flora, although it is not impossible. A drug may be bactericidal, meaning it kills the pathogen; or bacteriostatic, meaning it prevents reproduction of the pathogen, but this is not related to superinfections.
A client has been diagnosed with an infection. The nurse can help to ensure the success of anti-infective treatment by: A) confirming that the medication prescribed is the drug of choice for the specific microorganism. B) teaching the client that significant adverse effects are expected, and must be endured during treatment. C) administering antihistamines, as ordered, to prevent the development of adverse effects. D) monitoring the client closely for signs of arrhythmias or cardiac ischemia.
A) confirming that the medication prescribed is the drug of choice for the specific microorganism. Explanation: In order for treatment to be effective, it is necessary for an anti-infective to be accurately matched to the offending pathogen. Anti-infectives do not normally cause cardiac adverse effects. The client should be taught that adverse effects can be managed and are not necessarily an inevitability that must be endured. Antihistamines do not prevent most adverse effects.
A client is receiving an aminoglycoside antibiotic for an infection. The nurse would monitor the client closely for: A) hearing loss. B) lethargy. C) visual changes. D) hallucinations.
A) hearing loss. Explanation: Aminoglycosides collect in the eighth cranial nerve and can cause hearing loss, dizziness, and vertigo. Lethargy and hallucinations may be associated with other anti-infective agents. Visual changes such as blindness are associated with chloroquine use.
A client is receiving aminoglycoside therapy. The nurse would be alert for: A) kidney dysfunction. B) hallucinations. C) lethargy. D) loss of vision.
A) kidney dysfunction. Explanation: Kidney dysfunction (i.e., nephrotoxicity) is associated with aminoglycosides. Hallucinations are not associated with the use of aminoglycosides. Lethargy is not associated with aminoglycoside therapy. Loss of vision is more commonly associated with neurotoxic agents such as chloroquine. Hearing loss is a possibility with aminoglycosides.
The nurse administering an anti-infective agent recognizes that the drug will destroy some human cells as well as pathogens because of the absence of: A) selective toxicity. B) virulence. C) resistance. D) antigens.
A) selective toxicity. Explanation: Although anti-infective agents target foreign organisms infecting the body of a human host, they do not possess selective toxicity, which is the ability to affect certain proteins or enzyme systems used only by the infecting organism but not by human cells. Virulence would apply to the destructive power of the infection, not the drug. Resistance is the pathogen's ability to no longer respond to specific anti-infectives. Antigens are proteins bound to the cell that help the body identify a cell as belonging (or not) in the body, and are not the cause of human cell destruction.
People taking antimicrobial drugs should be instructed to report any problem that could indicate adverse drug effects, lack of therapeutic response, or emergence of another infection. One such problem is: A) skin rash. B) headache. C) constipation. D) muscle soreness.
A) skin rash. Explanation: Clients should be instructed to report nausea, vomiting, diarrhea, skin rash, recurrence of symptoms for which the antimicrobial drug was prescribed, or signs of new infection (e.g., fever, cough, sore mouth, drainage). These problems may indicate adverse effects of the drug, lack of therapeutic response to the drug, or another infection.
A client has been diagnosed with osteomyelitis and has been prescribed clindamycin, a narrow spectrum antibiotic. When planning this client's care, the nurse should understand that: A) the microorganism causing the infection is likely known. B) the client likely has compromised immune function. C) broad spectrum antibiotics were likely administered without success. D) the care team wished to reduce the client's risk of adverse effects.
A) the microorganism causing the infection is likely known. Explanation: Narrow spectrum antibiotics are appropriate when the identity of the microorganism is known or strongly suspected. This is unrelated to the client's immune function. Broad spectrum drugs are not necessarily trialed before using narrow spectrum drugs. The risk of adverse effects is not the determining factor.
A client is to be started on an antibiotic. Which is most important to take into consideration before beginning the antibiotic regimen? A) Duration of symptoms B) Culture and susceptibility C) Client's hydration status D) Client's age and weight
B) Culture and susceptibility Explanation: Culture identifies the causative organism, and susceptibility tests determine which drugs are likely to be effective against the organism. The duration of symptoms and the client's hydration status, age, and weight are important, but not imperative, in determining the antibiotic of choice.
A client with an upper respiratory tract infection was prescribed roxithromycin, an antibiotic. The nurse tells the client that irregular administration of this medication could lead to what outcome? A) Decreased absorption of the drug B) Development of drug resistance C) Increased rate of elimination of the drug D) Increased chances of serious adverse events
B) Development of drug resistance Explanation: When there is irregular or indiscriminate use of antibiotics, certain pathogens may mutate or build a tolerance to the drug. The antibiotic then becomes ineffective against that organism. Irregular use does not affect the absorption or elimination of the drug or increase chances of serious adverse events of the antibiotic.
Some recent anti-infective agents have been developed that are completely free of adverse effects. A) True B) False
B) False Explanation: No anti-infective agent has yet to be developed that is completely free of adverse effects.
The pharmacology instructor is discussing ways to decrease the incidence and severity of adverse effects among children taking anti-infective agents. What would the instructor mention is one way to do this in children? A) Decrease dietary potassium. B) Keep clients well hydrated. C) Assess liver function weekly. D) Increase sodium in diet.
B) Keep clients well hydrated. Explanation: Because children can have increased susceptibility to the gastrointestinal and nervous system effects of anti-infectives, monitor hydration and nutritional status carefully. Clients should be encouraged to drink fluids. Decreasing dietary potassium, weekly assessment of liver function, or increasing sodium in the diet will not decrease the severity of adverse effects in children.
What information about antibiotic therapy should the nurse include in a client's medication education? A) Bacteria can remain in the body for 48 to 72 hours after the completion of antibiotic therapy. B) Maintenance of normal bacterial flora is essential to health during the therapy. C) The healthy human body hosts dozens of minor infections at any given time. D) An aseptic internal environment only exists in young adults.
B) Maintenance of normal bacterial flora is essential to health during the therapy. Explanation: Normal flora protects the human host in a variety of ways. For example, normal bowel flora synthesizes vitamin K and vitamin B complex. The intestinal flora also plays a role in digestion. Furthermore, by competing with potential pathogens for nutrients and by preventing adhesion and growth of pathogens, beneficial microorganisms interfere with the ability of potential pathogens to cause infections. None of the other options are accurate statements regarding antibiotic therapy.
To ensure that the most appropriate drug is being used to treat a pathogen, which would need to be done first? A) Using combination therapy B) Obtaining sensitivity testing C) Checking client allergies D) Evaluating the bactericidal effects
B) Obtaining sensitivity testing Explanation: Performing sensitivity testing on cultured microbes is important to evaluate the bacteria and determine which drugs are capable of controlling the particular organism. Once the sensitivity testing is completed, then the decision for the drug can be made. Combination therapy is used when appropriate after culture and when sensitivity testing has been completed. Checking client allergies also would be done after sensitivity testing but before administering the drug. The bactericidal effects of a drug may or may not play a role in the selection of the drug.
The nurse is administering vancomycin to a client and will monitor the client for adverse effects related to which body systems? (Select all that apply.) A) Cardiac B) Renal C) Hepatic D) Hearing E) Eyesight
B) Renal D) Hearing Explanation: Vancomycin should not be administered to clients with renal or hearing impairment, because this drug may cause increased problems in these areas. It is not known to aggravate cardiac, hepatic, or vision problems.
An adult client has been treated for strep throat with ampicillin by mouth. The client visits the occupational health nurse and reports vaginal itching. What organism is the cause of the vaginal itching? A) Klebsiella B) Enterobacter C) Candida D) Proteus
C) Candida Explanation: The yeast Candida is a normal resident of the vagina and the intestinal tract. An antibacterial drug may destroy the normal bacterial flora without affecting the fungal organism. Klebsiella, Enterobacter, and Proteus will not contribute to the development of a yeast infection.
An infant has been brought to the emergency department by the parents, and initial assessment is highly suggestive of bacterial meningitis. Consequently, the infant has been admitted, and empiric antibiotic therapy has been prescribed. The nurse should understand what characteristic of this infant's current treatment plan? A) Success or failure of treatment will not be apparent for several weeks. B) The infant will receive aggressive treatment with a narrow-spectrum antibiotic. C) Culture and sensitivity results of the infant's cerebrospinal fluid are still pending. D) The infant is suspected of having an antibiotic-resistant infection.
C) Culture and sensitivity results of the infant's cerebrospinal fluid are still pending. Explanation: Empiric therapy is based on an informed estimate of the most likely pathogen(s) given the client's signs and symptoms and the site of infection, as well as knowledge of communicable diseases currently infecting other people in the community. Because laboratory tests used to definitively identify causative organisms and to determine susceptibility to antibiotics usually require 48 to 72 hours, the prescriber usually initiates treatment with an antimicrobial drug that is likely to be effective. The other listed statements are not true of empiric therapy.
Bacitracin (Baciguent) interferes with the cell wall synthesis of which type of bacteria? A) Proteus B) Streptococcal C) Staphylococcal D) Pseudomonas
C) Staphylococcal Explanation: Bacitracin is an antibiotic that interferes with the cell wall synthesis of susceptible staphylococcal bacteria.
The nurse understands that an infection caused by a secondary pathogen, which can occur during prolonged antibiotic therapy, is known as which of the following? A) Acquired resistance B) Cross-sensitivity C) Superinfection D) Primary infection
C) Superinfection Explanation: A superinfection is an infection caused by a secondary pathogen that can occur during prolonged antibiotic therapy.
When describing an anti-infective agent with a narrow spectrum of activity, what would the nurse include? A) The drug is effective against many different organisms. B) The drug is highly aggressive in killing the pathogen. C) The drug is selective in its action on organisms. D) The drug is effective in interfering with the cell's reproduction.
C) The drug is selective in its action on organisms. Explanation: An anti-infective with a narrow spectrum of activity is selective in its action; thus, it is effective against only a few microorganisms with a very specific metabolic pathway or enzyme. Broad-spectrum activity refers to effectiveness against a wide variety of pathogens. Bactericidal refers to a highly aggressive drug that causes cell death. Bacteriostatic refers to a drug's effectiveness in interfering with a cell's ability to reproduce or divide.
Aminoglycoside antibiotics tend to collect in the eighth cranial nerve. The nurse would anticipate that which clinical manifestation may occur from the cranial nerve involvement? A) Inability to swallow B) Blindness C) Vertigo D) Slurred speech
C) Vertigo Explanation: The aminoglycosides antibiotics collect in the eighth cranial nerve and can cause dizziness, vertigo, and loss of hearing.
When an anti-infective's function is to destroy the infective pathogen, it is classified as: A) resistant. B) bacteriostatic. C) bactericidal. D) sensitive.
C) bactericidal. Explanation: Anti-infectives can act to destroy an infective pathogen (bactericidal) or to prevent the pathogen from reproducing (bacteriostatic). Resistance is the ability over time to adapt to an anti-infective drug and produce cells that are no longer affected by a particular drug. Culture and sensitivity testing identify the causal pathogen and the most appropriate drug for treating the infection.
What intervention is most important for the nurse to perform before antibiotic therapy is initiated? A) increasing the client's fluid intake B) educating the client about adverse effects C) obtaining a specimen for culture and sensitivity D) administer an antidiarrheal to prevent gastrointestinal (GI) upset
C) obtaining a specimen for culture and sensitivity Explanation: It is good practice to collect specimens (e.g., sputum, urine) for culture and Gram's stain before giving the first dose of an antibiotic. Fluid intake and medication education may take place after the therapy is initiated, while antidiarrheal medication is administered if the client demonstrates signs/symptoms of GI distress.
What would a nurse least expect as an adverse reaction to anti-infective agents? A) kidney damage B) hypersensitivity C) respiratory toxicity D) neurotoxicity
C) respiratory toxicity Explanation: The least commonly encountered adverse effect associated with the use of anti-infective agents is respiratory toxicity. The most commonly encountered adverse effects are direct toxic effects on the kidney, gastrointestinal tract, and nervous system along with hypersensitivity and superinfections.
What occurs when the normal flora is destroyed by the use of anti-infectives? A) neurotoxicity B) hypersensitivity C) superinfection D) resistance
C) superinfection Explanation: Destruction of the normal flora by anti-infectives commonly leads to superinfection, an infection that occurs when opportunistic pathogens that were kept in check by the normal bacteria have the opportunity to invade the tissues. Neurotoxicity involves damage or interference with the function of nerve tissue, usually in areas where drugs tend to accumulate in high concentrations. Hypersensitivity or allergic reactions result from antibody formation. Resistance refers to the ability over time to adapt to an antibiotic and produce cells that are no longer affected by a particular drug.
Which type of testing should be completed prior to an anti-infective being prescribed? A) H & H B) CBC C) EKG D) Culture
D) Culture Explanation: Culture and sensitivity testing should be performed before an anti-infective agent is prescribed.
A group of nursing students are learning about the factors that underlie recent increases in the incidence and prevalence of antibiotic-resistant microorganisms. What factor is known to contribute to antibiotic resistance? A) Increased survival rates from acute infections B) Increased population density C) Use of antibiotics that are ineffective against the infectious microorganism D) Overuse of antibiotics
D) Overuse of antibiotics Explanation: Antibiotic overuse can contribute to antibiotic resistance. Resistance is not typically attributable to increased age of clients, increased population density, or the use of ineffective antibiotics.
A nurse is instructing a colleague on how an antimicrobial produces a therapeutic effect. What should be included in the nurse's teaching? A) Fluoroquinolones interfere with the growth and development of the bacteria cell wall. B) The first drugs used to treat infections date back to the 17th century. C) Selective toxicity determines the appropriate drug dosage needed. D) Penicillin interferes with synthesis of the bacteria cell wall.
D) Penicillin interferes with synthesis of the bacteria cell wall. Explanation: The action of antimicrobials is to interfere with the normal function of the invading organism to prevent it from reproducing and to cause cell death without affecting host cells. Penicillin interferes with biosynthesis of the bacterial cell wall. Because bacteria cells have a slightly different composition than human cells, the bacteria are destroyed without interfering with the host. The first drugs used to treat systemic infections were developed in the early 20th century. Fluoroquinolones act by interfering with DNA synthesis. Sulfonamides interfere with growth and development of bacterial cells. The term selective toxicity refers to the ability to affect certain proteins or enzyme systems that are used by infecting organisms but not by human cells.
After teaching a group of students about resistance, the instructor determines that the students need additional teaching when they identify what as a way that microorganisms develop resistance? A) Production of an enzyme that deactivates the drug B) Change in cellular permeability preventing drug entrance C) Altered binding sites that no longer accept the drug D) Production of a chemical to act as an agonist
D) Production of a chemical to act as an agonist Explanation: Microorganisms develop resistance by producing a chemical that acts as an antagonist not agonstic to the drug. In addition, the microorganism can produce an enzyme that deactivates the drug, change cellular permeability so that the drug cannot enter the cell, and alter binding sites to no longer accept the drug.
A female client calls the pediatrician's office because her child reports a sore throat. The nurse anticipates the pediatrician will take what action? A) Order an antibiotic. B) Order an antitussive. C) Request a list of drug allergies. D) Request a throat culture.
D) Request a throat culture. Explanation: For sore throat, a throat culture for streptococcal organisms should be performed and the results obtained before an antibiotic is prescribed.
A medical nurse on a night shift is reviewing a client's medication administration record for the following day. The nurse notes that a combination antimicrobial drug is prescribed. What is implied by the fact that the client has been prescribed a combination drug? A) The client's infection likely has a fungal or protozoal etiology. B) The client likely has a history of recurrent, multisystemic infections. C) The client may be unable to tolerate treatment with a single antimicrobial. D) The client may have an infection caused by multiple microorganisms.
D) The client may have an infection caused by multiple microorganisms. Explanation: Indications for combination therapy may include infections caused by multiple microorganisms. A fungal or protozoal infection is not implied, and the client may or may not have a history of recurrent infections. Intolerance of single antibiotics is not normally an indication for combination therapy.
A nurse has questioned why a client's health care provider has prescribed a narrow-spectrum antibiotic rather than a broad-spectrum drug in the treatment of an infection. Which facts provide the best rationale for the use of narrow-spectrum antibiotics whenever possible? A) Broad-spectrum antibiotics confound the results of subsequent culture and sensitivity testing. B) Narrow-spectrum antibiotics normally require a shorter duration of treatment. C) The efficacy of most narrow-spectrum antibiotics has not been proven. D) The use of broad-spectrum antibiotics can create a risk for a superinfection.
D) The use of broad-spectrum antibiotics can create a risk for a superinfection. Explanation: The benefit of a narrow-spectrum antimicrobial agent is that it limits the potential for adverse effects, such as superinfection. In a superinfection, an antibiotic suppresses all susceptible microbes, including the body's natural flora, which may keep other microbes in check. In the absence of these bacteria, nonsusceptible microbes can proliferate. Narrow-spectrum antibiotics do not lack demonstrated efficacy and they do not necessarily require a shorter duration of treatment. All antimicrobial drugs have the potential to impact subsequent C&S testing.
Like many other classes of drugs, anti-infective drugs can have a variety of adverse effects. What is the most common, potentially serious, adverse effect of antimicrobial drugs? A) Skin rash B) Pain C) Constipation D) Toxic effects on the kidney
D) Toxic effects on the kidney Explanation: The most commonly encountered adverse effects associated with the use of anti-infective agents are direct toxic effects on the kidney, gastrointestinal (GI) tract, and nervous system. Pain, constipation, and hypopnea are not common adverse effects of antimicrobial drugs.
A group of students are reviewing information about anti-infective agents. The students demonstrate a need for additional review when they identify what as an anti-infective agent? A) antibiotic B) anthelmintic C) antiprotozoal D) anticoagulant
D) anticoagulant Explanation: An anticoagulant interferes with blood clotting and is not an anti-infective agent. Antibiotics, anthelmintics, antiprotozoals, antivirals, and antifungals are all anti-infective agents.
Resistance
ability of pathogens over time to adapt to an antiinfective to produce cells that are no longer affected by a particular drug
Antiinfective agents
are drugs designed to target foreign organisms that have invaded and infected the body of a human host. For centuries, people have used various naturally occurring chemicals in an effort to treat disease. Often this was a random act that proved useful. For instance, the ancient Chinese found that applying moldy soybean curds to boils and infected wounds helped prevent infection or hastened cure. Their finding was, perhaps, a forerunner to the penicillins used today.
sensitivity testing
evaluation of pathogens obtained in a culture to determine the antiinfectives to which the organisms are sensitive and which agent would be appropriate for treatment of a particular infection
superinfection
infections that occur when opportunistic pathogens that were kept in check by the "normal" bacteria have the opportunity to invade tissues and cause infections because the normal flora bacteria have been destroyed by antibiotic therapy
spectrum
range of bacteria against which an antibiotic is effective (e.g., broad-spectrum antibiotics are effective against a wide range of bacteria; narrow-spectrum antibiotics are effective only against very selective bacteria)
Culture
sample of the bacteria (e.g., from sputum, cell scrapings, urine) to be grown in a laboratory to determine the species of bacteria that causes an infection
Bactericidal
substance that causes the death of bacteria, usually by interfering with cell membrane stability or with proteins or enzymes necessary to maintain the cellular integrity of the bacteria
Bacteriostatic
substance that prevents the replication of bacteria, usually by interfering with proteins or enzyme systems necessary for reproduction of the bacteria
selective toxicity
the ability to affect certain proteins or enzyme systems that are used by the infecting organism but not by human cells
Prophylaxis
treatment to prevent an infection before it occurs, as in the use of antibiotics to prevent bacterial endocarditis in high-risk patients or antiprotozoals to prevent malaria
