BMS2037: Antimicrobial Chemotherapy
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Questions and Answers

What was the major challenge in producing penicillium?

  • Difficulty in culturing
  • Difficulty in administering
  • Difficulty in purifying (correct)
  • Difficulty in discovering

    • Who discovered streptomycin and in what year?

  • Flemming, 1941
  • Miller, 1943
  • Waksman, 1944 (correct)
  • Fleming, 1942

    • What was used by ancient Greeks against tapeworms and roundworms?

  • Chaulmoogra oil
  • Arsenicals
  • Chenopodium ambrosioides (wormseed goosefoot) (correct)
  • Carbolic acid

    • What was the significance of streptomycin?

    <p>First antibiotic against tuberculosis</p> Signup and view all the answers

    What was Lister's contribution to treatment of infections?

    <p>Use of carbolic acid to treat wound infections</p> Signup and view all the answers

    What was the source of streptomycin?

    <p>Streptomyces griseus</p> Signup and view all the answers

    What is the mechanism of action of bleach as a biocide?

    <p>Denaturing proteins</p> Signup and view all the answers

    What is the stage of infection targeted by most antibiotics?

    <p>Multiplication in host tissue</p> Signup and view all the answers

    What is the mechanism of action of beta-lactams?

    <p>Inhibition of cell wall formation</p> Signup and view all the answers

    What was used to treat syphilis in the early 20th century?

    <p>Mercury</p> Signup and view all the answers

    What was the limitation of sulfa drugs developed in the 1930s?

    <p>Limited spectrum of activity</p> Signup and view all the answers

    What is the mechanism of action of sulphonamides?

    <p>Inhibition of metabolic pathways</p> Signup and view all the answers

    What is the common name for Chenopodium ambrosioides?

    <p>All of the above</p> Signup and view all the answers

    What is the stage of infection where the host defences are usually able to regain control?

    <p>Multiplication in host tissue</p> Signup and view all the answers

    What was used to treat leprosy in the past?

    <p>Chaulmoogra oil</p> Signup and view all the answers

    What is the percentage of IMS (isopropyl alcohol) commonly used as a biocide?

    <p>70%</p> Signup and view all the answers

    What is the mechanism of action of Vancomycin?

    <p>Prevention of transglycosylation</p> Signup and view all the answers

    What type of organisms harbor Extended-Spectrum Beta-Lactamases (ESBLs)?

    <p>Gram-negative organisms</p> Signup and view all the answers

    What is the function of Penicillin-Binding Proteins (PBPs)?

    <p>Formation of cross-links between peptidoglycan chains</p> Signup and view all the answers

    What is the consequence of beta-lactam antibiotics binding to PBPs?

    <p>Cell lysis</p> Signup and view all the answers

    What is the mechanism of action of Beta-Lactamase enzyme?

    <p>Hydrolysis of beta-lactam ring</p> Signup and view all the answers

    What is the consequence of Escherichia coli harboring ESBLs?

    <p>Increased resistance to beta-lactam antibiotics</p> Signup and view all the answers

    What is the characteristic of Vancomycin-Resistant Enterococci (VRE)?

    <p>Resistance to Vancomycin</p> Signup and view all the answers

    What is the characteristic of Cephalosporins?

    <p>Presence of a dihydrothiazine ring</p> Signup and view all the answers

    What is the primary mechanism of action of quinolones?

    <p>Binding to gyrase, causing DNA uncoiling</p> Signup and view all the answers

    Which of the following macrolides has improved bioavailability and half-life?

    <p>Azithromycin</p> Signup and view all the answers

    What is the primary function of topoisomerases in bacterial chromosome replication?

    <p>Untwisting of supercoiled DNA by nicking one of the strands</p> Signup and view all the answers

    What is the limitation of 1st generation quinolones, such as nalidixic acid?

    <p>They have a limited antibacterial spectrum of activity</p> Signup and view all the answers

    What is the general mechanism of action of inhibitors of nucleic acid synthesis?

    <p>Interruption of nucleotide metabolism and synthesis, perturbation of DNA as a template, and inhibition of enzymatic processes</p> Signup and view all the answers

    What is the significance of the interaction between gyrase, DNA, and quinolone molecules?

    <p>It stimulates the binding of quinolone to DNA</p> Signup and view all the answers

    Which of the following quinolones is classified as a 3rd generation quinolone?

    <p>Lomefloxacin</p> Signup and view all the answers

    How many gene products are involved in bacterial chromosome replication, according to the quinolone mechanism of action?

    <p>18</p> Signup and view all the answers

    What type of infections is gonorrhoeae linked with?

    <p>UTIs, hospital acquired pneumonia, line infections, and sepsis</p> Signup and view all the answers

    What is the mechanism of action of beta-lactamase inhibitors?

    <p>They inhibit the beta-lactamase enzyme, allowing the antibiotic to work effectively</p> Signup and view all the answers

    What is the key difference between beta-lactams and vancomycin?

    <p>Beta-lactams bind to transpeptidase, while vancomycin binds to the D-alanyl-D-alanine terminus of the growing peptidoglycan chain</p> Signup and view all the answers

    What is the mechanism of action of polymyxins?

    <p>They disrupt the inner and outer cell membranes, causing cell lysis</p> Signup and view all the answers

    What is the role of autolysins in bacterial cell wall synthesis?

    <p>They break down the bacterial cell wall, allowing for the insertion of new peptidoglycan</p> Signup and view all the answers

    What is the characteristic of beta-lactamase inhibitors that allows them to be effective?

    <p>They are able to bind irreversibly to the beta-lactamase enzyme</p> Signup and view all the answers

    What is the result of the inhibition of transpeptidase by beta-lactams?

    <p>The cell wall becomes weaker and more prone to lysis</p> Signup and view all the answers

    What is the difference between the mechanisms of action of beta-lactams and polymyxins?

    <p>Beta-lactams inhibit cell wall synthesis, while polymyxins disrupt the cell membrane</p> Signup and view all the answers

    Triclosan is effective against viruses.

    <p>False</p> Signup and view all the answers

    Arsphenamine is a true antibiotic.

    <p>False</p> Signup and view all the answers

    Penicillium rubens is the species used for drug production.

    <p>False</p> Signup and view all the answers

    Antibiotics work by affecting targets found in mammalian eukaryotic cells.

    <p>False</p> Signup and view all the answers

    Bisphenol is effective against spores.

    <p>False</p> Signup and view all the answers

    Chlorine denatures lipids.

    <p>False</p> Signup and view all the answers

    Antimicrobial components were produced in sufficient quantities and purity for clinical use during the 1920s.

    <p>False</p> Signup and view all the answers

    Salvarsan is a broad-spectrum antibiotic.

    <p>False</p> Signup and view all the answers

    Streptomycin was discovered from Streptomyces griseus in 1942.

    <p>False</p> Signup and view all the answers

    Penicillin is typically used to treat tuberculosis.

    <p>False</p> Signup and view all the answers

    Quinolones target the cell wall/membrane to inhibit bacterial growth.

    <p>False</p> Signup and view all the answers

    Daptomycin is an antibiotic that targets protein synthesis.

    <p>False</p> Signup and view all the answers

    Most antibiotics target the attachment of bacteria to the epithelial surface.

    <p>False</p> Signup and view all the answers

    Sulphonamides are a type of antibiotic that targets the cell wall/membrane.

    <p>False</p> Signup and view all the answers

    Isoniazid is an antibiotic that targets protein synthesis.

    <p>False</p> Signup and view all the answers

    Metronidazole is effective against bacterial infections.

    <p>False</p> Signup and view all the answers

    Glycopeptides bind to the growing peptidoglycan chain and prevent transpeptidation.

    <p>False</p> Signup and view all the answers

    Vancomycin is often regarded as an antibiotic of first resort.

    <p>False</p> Signup and view all the answers

    Penicillin-binding proteins (PBPs) are responsible for transglycosylation in the growing cell wall.

    <p>False</p> Signup and view all the answers

    Cephalosporins have a beta-lactam ring with a dihydrothiazine ring and a pentapeptide.

    <p>False</p> Signup and view all the answers

    Beta-lactamase enzymes are produced by Gram-positive organisms.

    <p>False</p> Signup and view all the answers

    ESBLs (Extended-Spectrum Beta-Lactamases) are harbored by Gram-positive organisms.

    <p>False</p> Signup and view all the answers

    Vancomycin binds to penicillin-binding proteins (PBPs) in the growing cell wall.

    <p>False</p> Signup and view all the answers

    Resistant organisms modify cell-wall precursors by replacing D-alanine with D-serine.

    <p>False</p> Signup and view all the answers

    The rate of mcr-1 clinical resistance in E. coli in China was estimated to be 0.7% in 2016.

    <p>False</p> Signup and view all the answers

    Colistin is effective against Pseudomonas aeruginosa.

    <p>False</p> Signup and view all the answers

    Tigecycline is effective against all Gram-negative bacteria.

    <p>False</p> Signup and view all the answers

    The rate of mcr-1 positive faecal E. coli samples from clinical settings was 20% in 2022.

    <p>False</p> Signup and view all the answers

    Quinupristin-dalfopristin is effective against Gram-negative bacteria.

    <p>False</p> Signup and view all the answers

    Linezolid is effective against Gram-negative bacteria.

    <p>False</p> Signup and view all the answers

    Ceftazidime is a type of beta-lactamase inhibitor.

    <p>False</p> Signup and view all the answers

    Polymyxins are effective against both Gram-positive and Gram-negative bacteria.

    <p>False</p> Signup and view all the answers

    Transpeptidase enzymes break peptide bonds in bacterial cell wall synthesis.

    <p>False</p> Signup and view all the answers

    Beta-lactamase inhibitors must bind reversibly to beta-lactamase to be effective.

    <p>False</p> Signup and view all the answers

    Vancomycin targets the stage of infection where the host defenses are usually able to regain control.

    <p>False</p> Signup and view all the answers

    Gonorrhoeae is linked with infections such as UTIs and hospital-acquired pneumonia.

    <p>True</p> Signup and view all the answers

    The mechanism of action of beta-lactams is to disrupt the inner and outer cell membranes.

    <p>False</p> Signup and view all the answers

    Clavulanate is a type of beta-lactam antibiotic.

    <p>False</p> Signup and view all the answers

    Which bacterium is commonly associated with catheterisation or instrumentation?

    <p>Staphylococcus epidermidis</p> Signup and view all the answers

    What is the recommended treatment for uncomplicated lower UTI in adults and children over 3 months old?

    <p>Trimethoprim and nitrofurantoin</p> Signup and view all the answers

    Why should quinolones be avoided in pregnancy?

    <p>They can cause congenital abnormalities</p> Signup and view all the answers

    What is a concern in patients with E. coli that produces ESBL enzymes?

    <p>Increased risk of resistance to multiple antibiotics</p> Signup and view all the answers

    Why is nitrofurantoin avoided at term in pregnancy?

    <p>It can cause hemolysis in the newborn</p> Signup and view all the answers

    What is the typical treatment route for upper UTI (acute pyelonephritis)?

    <p>IV antibiotics initially, followed by oral antibiotics</p> Signup and view all the answers

    What is the primary consequence of stepwise proliferation of antimicrobial-tolerant strains?

    <p>Development of resistance to antibiotics</p> Signup and view all the answers

    What is the characteristic of aminoglycosides in the context of Pseudomonas aeruginosa?

    <p>Increasing resistance among members of this group</p> Signup and view all the answers

    What is the significance of the sustained presence of antibiotics?

    <p>It allows the small population of tolerant cells to replicate</p> Signup and view all the answers

    What is the consequence of ineffective treatment against Pseudomonas aeruginosa?

    <p>Only a few members of the beta-lactam group are effective</p> Signup and view all the answers

    What is the role of specialist anti-pseudomonal antibiotics?

    <p>To treat Pseudomonas aeruginosa infections</p> Signup and view all the answers

    What is the significance of beta-lactam antibiotics?

    <p>Only a few members of this group are effective against Pseudomonas aeruginosa</p> Signup and view all the answers

    What is the term for bacteria having a higher-than-expected minimum inhibitory concentration (MIC)?

    <p>Tolerance</p> Signup and view all the answers

    What is the purpose of determining the minimum inhibitory concentration (MIC)?

    <p>To determine the susceptibility of bacteria to antibiotics</p> Signup and view all the answers

    What is the principle behind the disc-diffusion method of measuring antibiotic susceptibility?

    <p>Antibiotics diffuse into the agar, creating a radial concentration gradient</p> Signup and view all the answers

    What is the significance of antibiotic breakpoints?

    <p>They interpret the results of antibiotic susceptibility tests</p> Signup and view all the answers

    What is the advantage of molecular methods for ascertaining resistance?

    <p>They can identify specific resistance genes</p> Signup and view all the answers

    What is the consequence of selective pressure on bacterial populations?

    <p>Increased resistance to antibiotics</p> Signup and view all the answers

    What is the primary reason for preserving and conserving penicillin despite Staphylococcus aureus resistance?

    <p>It is still important for treating Streptococcal infections, Syphilis, and Listeriosis.</p> Signup and view all the answers

    What is the current recommended treatment for Gonococcal disease?

    <p>Ceftriaxone and Azithromycin</p> Signup and view all the answers

    What is the most common cause of urinary tract infections?

    <p>E. coli</p> Signup and view all the answers

    What is the consequence of untreated urinary tract infections?

    <p>All of the above</p> Signup and view all the answers

    Why are steroids preferably administered before the first antibiotic dose in Meningococcal disease treatment?

    <p>To reduce the risk of shock</p> Signup and view all the answers

    What is the primary mechanism of action of antibiotics used to treat Meningococcal disease?

    <p>Inhibition of cell wall synthesis</p> Signup and view all the answers

    What is the significance of benzyl penicillin and amoxicillin in the treatment of Meningococcal disease?

    <p>They are used to treat Meningococcal disease and have a low risk of resistance</p> Signup and view all the answers

    What is the primary role of vasoactive treatments in Meningococcal disease?

    <p>To reduce the risk of shock</p> Signup and view all the answers

    What is a consequence of antimicrobial resistance according to the WHO?

    <p>Longer hospital stays</p> Signup and view all the answers

    What is the projected total global antibiotic consumption from 2000 to 2030?

    <p>Billions of DDDs</p> Signup and view all the answers

    What is a major challenge posed by antimicrobial resistance?

    <p>Compromised organ transplants</p> Signup and view all the answers

    What is the estimated number of surgical admissions in the UK per year?

    <p>4.5 million</p> Signup and view all the answers

    What is the percentage of the UK population that has diabetes?

    <p>6%</p> Signup and view all the answers

    What is the title of the review on antimicrobial resistance?

    <p>Antimicrobial Resistance: Tackling a Crisis</p> Signup and view all the answers

    What is the estimated number of new cancer cases per year?

    <p>350,000</p> Signup and view all the answers

    What is the estimated number of transplants per year?

    <p>5,000</p> Signup and view all the answers

    Pseudomonas aeruginosa is often associated with catheterisation or instrumentation.

    <p>False</p> Signup and view all the answers

    Nitrofurantoin is avoided during pregnancy.

    <p>False</p> Signup and view all the answers

    E. coli with ESBL enzymes are sensitive to nitrofurantoin.

    <p>True</p> Signup and view all the answers

    Upper UTI treatment usually involves oral antibiotics.

    <p>False</p> Signup and view all the answers

    Staphylococcus epidermidis is usually associated with sexually active people.

    <p>False</p> Signup and view all the answers

    Trimethoprim is avoided in patients with renal impairment.

    <p>False</p> Signup and view all the answers

    Staph.aureus resistance to penicillin makes it an ineffective treatment for meningitis.

    <p>False</p> Signup and view all the answers

    Neisseria gonorrhoea is susceptible to all antibiotics introduced for its treatment.

    <p>False</p> Signup and view all the answers

    Cefixime is a first-line treatment for Meningococcal disease.

    <p>False</p> Signup and view all the answers

    E.coli is a rare causative organism of urinary tract infection.

    <p>False</p> Signup and view all the answers

    Klebsiella / Proteus spp. are rare causative organisms of urinary tract infection.

    <p>False</p> Signup and view all the answers

    Penicillin is the primary treatment for Syphilis.

    <p>True</p> Signup and view all the answers

    Only a few members of the aminoglycoside group are effective against Pseudomonas aeruginosa.

    <p>False</p> Signup and view all the answers

    Benzyl penicillin is a second-line treatment for Meningococcal disease.

    <p>False</p> Signup and view all the answers

    The presence of an antibiotic leads to the immediate elimination of all bacterial mutants.

    <p>False</p> Signup and view all the answers

    Specialist anti-pseudomonal antibiotics are rarely used to treat Pseudomonas aeruginosa.

    <p>False</p> Signup and view all the answers

    Steroids are used as a maintenance therapy for shock in Meningococcal disease.

    <p>True</p> Signup and view all the answers

    The stepwise proliferation of antimicrobial-tolerant strains can lead to increased sensitivity to antibiotics.

    <p>False</p> Signup and view all the answers

    Beta-lactam antibiotics are effective against Pseudomonas aeruginosa due to its lack of resistance to this group.

    <p>False</p> Signup and view all the answers

    The sustained presence of antibiotics can lead to the elimination of all tolerant cells.

    <p>False</p> Signup and view all the answers

    A broth dilution test measures the minimum bactericidal concentration of an antibiotic.

    <p>False</p> Signup and view all the answers

    Tolerance to antibiotics is the same as resistance to antibiotics.

    <p>False</p> Signup and view all the answers

    Antibiotic breakpoints are based on the MIC of an antibiotic.

    <p>False</p> Signup and view all the answers

    Molecular methods for ascertaining resistance require phenotypic methods to identify the MIC.

    <p>False</p> Signup and view all the answers

    The disc-diffusion test measures the MIC of an antibiotic.

    <p>False</p> Signup and view all the answers

    Quantitative methods for measuring antibiotic susceptibility and resistance are only used for research purposes.

    <p>False</p> Signup and view all the answers

    Around 6% of the UK population have diabetes.

    <p>True</p> Signup and view all the answers

    The predicted total global antibiotic consumption from 2000 to 2030 is in millions of DDDs.

    <p>False</p> Signup and view all the answers

    The book 'Microbiology – An introduction' by Tortora, GJ is the main textbook for the module.

    <p>True</p> Signup and view all the answers

    The Review on Antimicrobial Resistance was chaired by Eili Y. Klein.

    <p>False</p> Signup and view all the answers

    Around 5000 organ transplants are performed every year.

    <p>True</p> Signup and view all the answers

    The book 'Antibiotics and Chemotherapy: anti-infective agents and their use in therapy' by Finch et al. is available on Bibliu.

    <p>False</p> Signup and view all the answers

    Antimicrobial resistance is predicted to cause more deaths than cancer chemotherapy by 2030.

    <p>True</p> Signup and view all the answers

    The ISBN of the book 'Antimicrobial Chemotherapy' by Greenwood et al. is 0443071292.

    <p>False</p> Signup and view all the answers

    Study Notes

    A Brief History of Antimicrobial Chemotherapy

    • Early treatments against infectious diseases:
      • Oils and crude plant extracts as anti-helminths (e.g. Chenopodium ambrosioides for tapeworms and roundworms)
      • Quinine for malaria
      • Mercury for syphilis
      • Chaulmoogra oil for leprosy
    • Lister used carbolic acid to treat wound infections, but it had low efficacy and was damaging to healthy tissue
    • In the 1900s, arsenicals were used as antiprotozoal agents and for schistosomiasis and syphilis
    • Sulfa drugs were introduced in the 1930s, but had a limited spectrum of activity

    Biocides: Disinfectants and Antiseptics

    • 70% IMS/isopropyl alcohol/rubbing alcohol: denatures proteins and has a broad spectrum of activity
    • Bleach: difficult to purify and produce in clinically useful amounts

    Mechanisms of Action and Resistance

    • Nucleic acid synthesis inhibitors:
      • Quinolones bind to unpaired DNA bases and have a complex interaction with gyrase, DNA, and quinolone molecules
      • Inhibit topoisomerases, which untwist supercoiled DNA by 'nicking' one of the strands
    • Cell wall/membrane inhibitors:
      • Beta-lactams (e.g. penicillin) bind to penicillin-binding proteins (PBPs) in the growing cell wall, inhibiting cross-links between peptidoglycan chains and leading to cell lysis
      • Vancomycin binds to the growing peptidoglycan chain and prevents transglycosylation
    • Protein synthesis inhibitors:
      • Anti-metabolites (e.g. sulphonamides, trimethoprim) inhibit enzyme activity
      • Glycopeptides (e.g. vancomycin) bind to the growing peptidoglycan chain and prevent transglycosylation

    Beta-Lactam Antibiotics

    • Mechanism of action:
      • Bind to penicillin-binding proteins (PBPs) in the growing cell wall
      • Inhibit cross-links between peptidoglycan chains, leading to cell lysis
    • Different classes of beta-lactams:
      • Penicillins (e.g. penicillin G, ampicillin)
      • Cephalosporins (e.g. cephalosporin C, cephalexin)
      • Extended-spectrum beta-lactams (ESBLs)
    • Beta-lactamase inhibitors:
      • Clavulanate: binds to beta-lactamase and inhibits its activity
      • Tazobactam: binds to beta-lactamase and inhibits its activity

    Inhibitors of Cell Membrane Function and Synthesis

    • Polymyxins:
      • Disrupt inner and outer cell membranes, causing cell lysis
      • Act only on Gram-negative bacteria

    Inhibitors of Nucleic Acid Synthesis

    • Quinolones:
      • Bind to unpaired DNA bases and have a complex interaction with gyrase, DNA, and quinolone molecules
      • Inhibit topoisomerases, which untwist supercoiled DNA by 'nicking' one of the strands
      • Have a broad spectrum of activity, with 1st, 2nd, 3rd, and 4th generation quinolones having increasing potency

    Antimicrobial Agents

    • Triclosan dissolves lipids and is ineffective against spores and some viruses.
    • Chlorine denatures proteins, affecting multiple targets in the membrane and cytoplasm.
    • Bisphenol is found in dentifrices and incorporated into plastic and fabrics.

    Principles of Selective Toxicity

    • Antibiotics work by targeting bacterial cells, not mammalian eukaryotic cells.
    • Antibiotics become concentrated in bacterial cells, not host cells.

    Types of Antibiotics

    • Bactericidal antibiotics kill bacteria, while bacteriostatic antibiotics inhibit bacterial growth.
    • Antibiotics vary in their ability to fulfill the criteria of selective toxicity.

    Discovery of Clinically Useful Antibiotics

    • Paul Ehrlich developed arsphenamine (Neosalvarsan) in 1912, which has limited activity against spirochaetes.
    • Penicillium chrysogenum is used for drug production, not Penicillium rubens, which was discovered by Flemming.
    • Mary Hunt discovered antimicrobial components in the 1930s.
    • Selman Waksman discovered streptomycin, the first drug to treat tuberculosis, in 1944.

    Mechanisms of Action

    • Nucleic acid inhibitors: quinolones, metronidazole
    • Cell wall/membrane inhibitors: beta-lactams, vancomycin
    • Protein synthesis inhibitors: sulphonamides, trimethoprim
    • Anti-metabolites: isoniazid

    Beta-Lactam Antibiotics

    • Bind to penicillin-binding proteins (PBPs) in growing cell walls
    • Inhibit cross-links between peptidoglycan chains, causing cell lysis
    • Cephalosporins have a beta-lactam ring with a dihydrothiazine ring
    • Different classes of beta-lactams: penicillinases, extended-spectrum beta-lactamases (ESBLs), metallo-beta-lactamases, cephalosporinases

    Beta-Lactamase Inhibitors

    • Have a lactam ring, but are weak antibiotics
    • Must have higher affinity for inhibitor than drug
    • Inhibitor must bind irreversibly to beta-lactamase
    • Examples: clavulanate, sulbactam

    Difference between Beta-Lactams and Vancomycin

    • Beta-lactams bind to transpeptidase, while vancomycin binds to the growing peptidoglycan chain
    • Autolysins break peptide bonds, but no further bonds are created with vancomycin

    Polymyxins

    • Disrupt inner and outer cell membranes, causing cell lysis
    • Act only on Gram-negatives
    • Examples: polymyxin B, polymyxin E (colistin)

    Impact of Colistin Resistance

    • First clinical infection caused by a colistin-resistant strain in the US in 2016
    • Estimated 1.4% of E. coli and 0.7% of Klebsiella pneumoniae isolates in China are resistant
    • Newer molecular measures are more reliable in detecting resistance

    Importance of Preserving Antibiotics

    • Despite Staphylococcus aureus resistance, penicillin remains important for treating:
      • Listeriosis
      • Meningitis
      • Streptococcal infections
      • Syphilis

    Treatment of Meningococcal and Gonococcal Diseases

    • Meningococcal disease:
      • Treated with IV antibiotics (benzyl penicillin or amoxicillin)
      • Rare occurrence of drug resistance
      • Maintenance therapy for shock (fluids, etc.)
      • Vasoactive treatments (IV adrenaline and steroids)
      • Experimental therapies (anti-cytokine and anti-endotoxin) have been investigated
    • Gonococcal disease:
      • Developed resistance to all antibiotics introduced for treatment
      • 3rd generation cephalosporins (e.g. cefixime or ceftriaxone) are first-line treatments
      • Dual treatments (e.g. ceftriaxone and azithromycin) are now recommended due to the emergence of "superbugs" resistant to ceftriaxone

    Urinary Tract Infections (UTIs)

    • Can cause fever, loin pain, and ascending infection
    • Secondary spread can lead to:
      • Renal abscess
      • Bacteremia
      • Pyelonephritis
      • Cystitis (exacerbated by urinary stasis)
      • Prostatitis
      • Urethritis
      • Epididymitis
    • Contamination from faecal/perineal flora is a common cause of UTIs
    • Aetiological agents of UTIs include:
      • E. coli (very common)
      • Klebsiella/Proteus spp. (less common)
      • Pseudomonas aeruginosa (hospital-associated)
      • Staphylococcus epidermidis (associated with catheterization or instrumentation)
      • Enterococcus faecalis
      • Chlamydia trachomatis (in sexually active people)
      • Neisseria gonorrhoea

    Treatment Guidelines and Precautions for UTIs

    • Uncomplicated lower UTI:
      • Trimethoprim and nitrofurantoin are recommended (concentrated in urine and remain active in the bladder)
      • Variations in dose for different patient groups
    • Pregnancy:
      • Avoid quinolones and trimethoprim
      • Nitrofurantoin: avoid at term, use amoxicillin or cephalosporin instead
    • E. coli with ESBL enzymes:
      • Increasing prevalence
      • Nitrofurantoin remains sensitive
    • Renal impairment:
      • Caution when using antibiotics in this patient group
    • Upper UTI (acute pyelonephritis):
      • Antibiotics are initially administered via IV route due to septicaemia risk
      • Cephalosporin, quinolone, and gentamicin are used
      • Pseudomonas aeruginosa has intrinsic resistance

    Antibiotic Resistance and Consequences

    • Antimicrobial resistance (AMR) compromises:
      • Organ transplant
      • Cancer chemotherapy
      • Diabetes management
      • Routine surgery (e.g. hip replacements, caesarians)
    • Other impacts of AMR:
      • Longer hospital stays
      • Longer time intubated
      • Longer duration of antibiotic treatment
      • Greater financial costs
    • Predicted deaths attributable to AMR are expected to surpass deaths from other causes by 2050

    Importance of Preserving Antibiotics

    • Despite Staphylococcus aureus resistance, penicillin remains important for treating:
      • Listeriosis
      • Meningitis
      • Streptococcal infections
      • Syphilis

    Treatment of Meningococcal and Gonococcal Diseases

    • Meningococcal disease:
      • Treated with IV antibiotics (benzyl penicillin or amoxicillin)
      • Rare occurrence of drug resistance
      • Maintenance therapy for shock (fluids, etc.)
      • Vasoactive treatments (IV adrenaline and steroids)
      • Experimental therapies (anti-cytokine and anti-endotoxin) have been investigated
    • Gonococcal disease:
      • Developed resistance to all antibiotics introduced for treatment
      • 3rd generation cephalosporins (e.g. cefixime or ceftriaxone) are first-line treatments
      • Dual treatments (e.g. ceftriaxone and azithromycin) are now recommended due to the emergence of "superbugs" resistant to ceftriaxone

    Urinary Tract Infections (UTIs)

    • Can cause fever, loin pain, and ascending infection
    • Secondary spread can lead to:
      • Renal abscess
      • Bacteremia
      • Pyelonephritis
      • Cystitis (exacerbated by urinary stasis)
      • Prostatitis
      • Urethritis
      • Epididymitis
    • Contamination from faecal/perineal flora is a common cause of UTIs
    • Aetiological agents of UTIs include:
      • E. coli (very common)
      • Klebsiella/Proteus spp. (less common)
      • Pseudomonas aeruginosa (hospital-associated)
      • Staphylococcus epidermidis (associated with catheterization or instrumentation)
      • Enterococcus faecalis
      • Chlamydia trachomatis (in sexually active people)
      • Neisseria gonorrhoea

    Treatment Guidelines and Precautions for UTIs

    • Uncomplicated lower UTI:
      • Trimethoprim and nitrofurantoin are recommended (concentrated in urine and remain active in the bladder)
      • Variations in dose for different patient groups
    • Pregnancy:
      • Avoid quinolones and trimethoprim
      • Nitrofurantoin: avoid at term, use amoxicillin or cephalosporin instead
    • E. coli with ESBL enzymes:
      • Increasing prevalence
      • Nitrofurantoin remains sensitive
    • Renal impairment:
      • Caution when using antibiotics in this patient group
    • Upper UTI (acute pyelonephritis):
      • Antibiotics are initially administered via IV route due to septicaemia risk
      • Cephalosporin, quinolone, and gentamicin are used
      • Pseudomonas aeruginosa has intrinsic resistance

    Antibiotic Resistance and Consequences

    • Antimicrobial resistance (AMR) compromises:
      • Organ transplant
      • Cancer chemotherapy
      • Diabetes management
      • Routine surgery (e.g. hip replacements, caesarians)
    • Other impacts of AMR:
      • Longer hospital stays
      • Longer time intubated
      • Longer duration of antibiotic treatment
      • Greater financial costs
    • Predicted deaths attributable to AMR are expected to surpass deaths from other causes by 2050

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    Learn about the history of antimicrobial chemotherapy, antibiotic drug classes, mechanisms of action and resistance, and understand recent trends in antimicrobial consumption.

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