Microbiology Blackboard Flashcards
Beta-Lactams
A. Penicillin B. Amoxicillin C. Tazobactam D. Ceftriaxone E. Clavulanic acid F. Cephalexin G. Flucloxacillin H. Piperacillin I. Meropenem J. Cefuroxime K. Ceftazidime
- Stable to ESBL enzymes.
- Effective against gram-positive organisms and stable to B-lactamases produced by S.aureus
- A broad-spectrum penicillin that extends coverage to Enterococci and gram negative organisms. Does not extend coverage to Pseudomonas.
- A β-lactamase inhibitors that is often given with amoxicillin
- A 3rd generation cephalosporin. Associated with C. difficile and advised to avoid use in neonates.
B-lactams are relatively non-toxic, really excreted, short half-life, generally will not cross intact BBB.
1) I. Meropenem is a Carbapenem (B-lactam). Carbapenems are stable to extended spectrum B-lactamases. However increasingly MDR Acinetobacter and Klebsialla species produce carbapenemase enzymes
2) G. Fluxocacillin is similar to Penicillin in that it is effective against gram-positive organisms only such as Strep/Clostridia, but it is less active and not broken down by B-lactamases produced by S.aureus
3. Amoxicillin is a broad-spectrum penicillin that extends coverage to Enterococci and gram negative organisms. Piperacillin is similar but also extends coverage to Pseudomonas.
4. E. Clavulanic acid is given with amoxicillin as co-amoxiclav. Tazobactam (another B-lactamase inhibitor is often given alongside piperacillin)
5. D. Ceftriaxone. contraindicated in neonates because it displaces bilirubin from albumin binding sites, resulting in a higher free bilirubin serum concentration and interacts with calcium. Ceftazidime is another 3rd gen ceph but with additional anti-pseudomonas activity.. Cefuroxime is a second generation.
Similar to the glycopeptide that can be used to treat serious C. difficile infection
Teicoplanin is a glycopeptide similar to vancomycin.
Active against gram + organisms but unable to penetrate gram- outer cell wall.
Inhibitors of Protein synthesis
A Chloramphenicol B. Gentamicin C Tetracyline D Clarithromycin E Ciprofloxacin F. Rifampicin. G. Lincosamide H. Macrolide
- Ototoxic/Nephrotoxic, particularly active against Pseudomonas. Bactericidil.
- Broad-spectrum agents with activity against intracellular pathogens (e.g. chlamydiae). May result in a light-sensitive rash.
- Macrolides. Useful in providing treatment alternative to penicillin allergic patients. Active against Campylobacter and Legionella.
- Risk of aplastic anaemia and grey baby syndrome.
- A DNA inhibitor, not direct inhibitor of protein synthesis.
- An RNA inhibitor, not direct inhibitor of protein synthesis.
- What class of antibiotic is Clindamycin?
1) B. Aminoglycosides (e.g. gentamicin, amikacin,tobramycin). Bind to amino-acyl site of 30s ribosomal subunit preventing elongation of polypeptide chain. Ototoxic/nephrotoxic
2) Tetracycline. Bacteriostatic, inhibits 30s ribosomal subunit.
3) . Clarithromycin Macrolides bind to 50s subunit. (e.g. erythromycin) / Lincosamides (clindamycin) / Streptogramins (Synercid) – The MSL group, Azithromycin.
4) Chloramphenicol - bacteriostatic. Risk of aplastic anaemia and grey baby syndrome (as neonates unable to metabolise the drug) so often just used for eye treatments. Binds to the peptidyl transferase of the 50S ribosomal subunit
5) Flouroquinolones/ ciprofloxacin.
6) Rifampicin Inhibits protein synthesis by binding to DNA-dependent RNA polymerase thereby inhibiting initiation
7) . L. Lincosamide. Clindamycin is in a class of medications called lincosamide antibiotics.
Oxazolidinones (e.g. Linezolid) - Binds to the 23S component of the 50S subunit to prevent the formation of a functional 70S initiation complex
Daptomycin – a cyclic lipopeptide with activity limited to G+ve pathogens. It is a recently-licenced antibiotic likely to be used for treating MRSA and VRE infections as an alternative to linezolid and Synercid
Colistin – a polymyxin antibiotic that is active against Gram negative organisms, including Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella. pneumoniae. It is not absorbed by mouth. It is nephrotoxic and should be reserved for use against multi-resistant organisms
A. Interferon-g (gamma) B. Cidofovir C. Foscarnet D. Aciclovir E. Zidovudine F. Neuraminidase inhibitor G. Aciclovir monophosphate H. Entecevir I. Interferon-b (beta) J. Nevirapine K. Interferon-α (alpha) L. Oseltamivir M. Ribavirin N. Ganciclovir O. Aciclovir triphosphate
- The antiviral which is given to untreated pregnant women with HIV to prevent vertical transmission of the virus during childbirth.
- An immunomodulatory therapy used in the treatment of hepatitis B.
- An antiviral currently used to prevent and treat Influenza in the elderly and which has the potential to be used to prevent Avian influenza.
- The final metabolite of the antiviral used to treat Herpes Simplex
- An antiviral which can be used in aerosol form to prevent respiratory syncytial virus in children with heart and lung disease
- (J) Nevirapine. Single-dose nevirapine prophylaxis for mother and baby significantly lowered HIV-1 infection risk at 14–16 weeks compared with controls who received short-course zidovudine prophylaxis. Can still give zidovudine.
- (K) Inteferon-a. HepB/C patients receive peg-infteferon-a
PEGylation is conjugation of interferon (IFN) with PolyEthylene Glycol. The conjugate has a longer half life
permitting once weekly rather than daily or thrice weekly injection than standard IFN.
IFN-beta used for multiple sclerosis. IFN-gamma may be used for chronic granulomatous disease. - (L) Oseltamivir
- (O) Aciclovir triphosphate. Aciclovir first gets phosphorylated by viral thymidine kinase to Aciclovir monophosphate. Then host cellular kinases turn this into Aciclovir-PPP, which inhibits viral DNA polymerase.
- Ribavirin.
Ribavirin, a nucleotide analogue, is the only antiviral drug approved by the Federal Drug Administration (FDA) for treatment of RSV disease.
Other nonapproved therapies have been used, including intravenous immunoglobulin (IVIG) and RSV hyperimmune IVIG (RSV-IVIG).
Palivizumab (PVZ), a humanized monoclonal antibody specific for RSV, is approved for prophylaxis of severe RSV infection in high-risk children, but there is little experience with its use for treatment of acute RSV infection in these high-risk patients.
A. Thymidine B. Influenza C. Cytomegalovirus D. Famciclovir E. Aciclovir diphosphate F. Aciclovir monophosphate G. Guanosine H. Aciclovir triphosphate I. Varicella-zoster virus J. Ribavarin K. AIDS
- Which option is the product of the action of viral tyrosine kinase on aciclovir?
- Which option inhibits the action of viral DNA polymerase?
- The synthetic nucleoside analogue ganciclovir is the drug of choice against which infective virus?
- Ribavirin, a synthetic nucleoside that acts as an RNA polymerase inhibitor, is similar in structure to which of the options given above?
- Valaciclovir, a prodrug of aciclovir, is used to treat patients with which viral disease in the list, above?
- Correct F. Aciclovir monophosphate
- Correct H. Aciclovir triphosphate
- Correct C. Cytomegalovirus
- Correct G. Guanosine
- i. Varicella-zoster virus
A. Ibuprofen B. Loviride C. Gancyclovir D. Ribavarin E. Citalapram F. Doxacyclin G. Zidovudine H. Interferon I. Amantadine J. Abacavir K. Foscarnet L. Aciclovir M. Adefovir
- An immunomodulator effective in HBV infection
- Used for the treatment of severe, resistant herpes infections
- The treatment of choice for CMV-induced hepatitis
- A drug that is effective against influenza A but not influenza B
- A purine nucleoside analogue that selects specifically for thymidine kinase
- Correct H. Interferon
- Correct K. Foscarnet (only IV)
- Correct C. Gancyclovir
- Correct I. Amantadine. Not used very much because of widespread resistance.
- Correct L. Aciclovir
HIV drugs to remember. What are their side-effects?
NRTIs: lamivudine and emtricitabine have minimal toxicity and are used in real life in preference to older drugs (AZT/zidovudine, stavudine/d4T, that caused pancreatitis, peripheral neuropathy, cytopenias, fatal hypersensitivity (abacavir)
NNRTIs: efavirenz and nevirapine
PIs: ritonavir and the rest (Indinavir, Amprenavir, Atazanavir, Saquinavir)
Fusion inhibitors: Enfuvirtide
Side effects
NRTIs: Lactic acidosis (type B)
NNRTIs: rash, Stevens Johnson syndrome, Toxic epidermal necrolysis, fatal fulminant hepatitis
PIs: insulin resistance, dyslipidaemia, lipodystrophy, bleeding in hemophilia
A. Aciclovir B. Ganciclovir C. Interferon D. Nevirapine E. Human normal immunoglobulin F. Efavirenz G. Human specific immunoglobulin H. Zidovudine I. Indinavir J. Amantadine K. Enfuvirtide L. Ribavarin M. Zanamivir
- A nucleoside analogue which inhibits reverse transcriptase
- The drug mechanisms which acts by stopping post-translational cleaving of polyproteins by inhibiting proteases
- The drug that is selectively toxic to virally infected cells through its selective phosphorylation using viral thymidine kinase
- The drug which can be delivered by inhalation to treat both influenza A and B.
- The drug which works by attenuating or preventing rabies or hepatitis, following a known exposure but before the onset of signs and symptoms.
- Correct H. Zidovudine - NRTI (lamivudine and emtricitabine)
- Correct I. Indinavir - Protease inhibitor. (ritonavir another example)
- Correct A. Aciclovir
- Correct M. Zanamivir -inhalation or IV
- Correct G. Human specific immunoglobulin
A. S. pneumoniae B. C. neoformans C. K. pneumoniae D. C. psittaci E. B. pertussis F. S. aureus G. L. pneumophila H. M. pneumoniae I. M. tuberculosis J. P. aeuruginosa
- A 40yr old female non-smoker presents with a one week history of fever, shortness of breath and a cough productive of rusty coloured sputum. She complains of a sharp chest pain which “catches” her on inspiration. On examination she has increased vocal resonance in the right middle zone on auscultation. The x-ray shows right middle lobe consolidation.
- A 37yr old American business man staying in a hotel presents with a headache, myalgia and a dry cough. He is also suffering with nausea, diarrhoea and abdominal pain. On examination he is tachypnoeic and has a pyrexia of 39ºC. Blood tests reveal lymphopenia and hyponatraemia.
- A 19yr old medical student who lives in residential halls presents with a one week history of headache, malaise, shortness of breath and a cough. Her WBC is not raised but tests reveal the presence of cold agglutinins.
- A 30yr old lady presents with a three week history of tiredness, malaise, cough and weight loss. She feels her condition has worsened in the past week and she now also suffers from a fever and haemoptysis. In addition she complains of a “tender lump” in her supraclavicular region. Chest x-ray demonstrates nodular shadowing of the right upper zone.
- A forty year old ornithologist presents with malaise, muscular pains and a cough. On examination he has a fever and several distinctive rose spots on his abdomen. Chest x-ray reveals a diffuse pneumonia.
- Dry cough, new infiltrates on CXR, dyspnoea and target shaped lesions on the palms. No recent history of herpes.
- Correct A. S. pneumoniae
- Correct G. L. pneumophila
- Correct H. M. pneumoniae
- Correct I. M. tuberculosis
- Correct D. C. psittaci
- Correct H. M. pneumoniae
A. H. influenzae B. Burkholderia cepacia C. MRSA D. S. pneumoniae E. PCP/ P jiroveci F. MSSA G. M tuberculosis H. Chlamydia psittaci I. Legionella pneumophila J. M. Catarrhalis K. Anaerobic infection L. MSSA or MRSA M. Chlamydia pneumoniae
- An 80 year old clown appears at the GP having been discharged from hospital for a complicated bowel resection with a stint in the ITU. He has a cough and fever and is prescribed a macrolide antibiotic because he is penicillin allergic.
- A 55 year old female clown, recovering from a cold, is found to have a cavitating lesion on CXR and a productive cough.
- An 18 year old trainee clown is being seen in the cystic fibrosis clinic and is found to be colonised with a particularly persistent organism.
- A 40 year old clown specialist is found to have a lobar pneumonia which on culture grew Gram +ve diplococci.
- A 35 year old clown who is a specialist in bird/clown comedy is found to have an atypical pneumonia which is treated with Augmentin and Clarythromicin
- Correct F. MSSA
- Correct L. MSSA or MRSA
- Correct B. Burkholderia cepacia
- Correct D. S. pneumoniae
- Correct H. Chlamydia psittaci
A. Herpes simplex virus type 1 (alpha) B. Human herpes virus 8 (gamma) C. Human herpes virus 7 D. Herpes simplex virus type 2 (alpha) E. Cytomegalovirus (beta) F. Varicella zoster virus (alpha) G. Human herpes virus 6 (beta) H. HIV I. Epstein-Barr virus (gamma)
- Pneumonitis after a bone marrow transplant
- Endemic Burkitt’s lymphoma
- Roseola infantum
- Blistering rash in dermatomal distribution
- Acute necrotising encephalitis
- Correct E. Cytomegalovirus (beta)
- Correct I. Epstein-Barr virus (gamma)
- Correct G. Human herpes virus 6 (beta)/ exanthum subitum.
- Correct F. Varicella zoster virus (alpha)
- Correct A. Herpes simplex virus type 1 (alpha) (also causes primary stomatitis)
Human Herpes Virus 8- Infection associated with Kaposi’s sarcoma
Herpes Simplex Type 2. Genital ulcers - Neonatal Infection associated with vaginal delivery
Alpha herpes viruses: neurotropic
Beta herpes viruses: epitheliotropic
Gamma herpes viruses: Lymphotropic
A. CCR5/CXCR4 B. Candidiasis C. Viral load (PCR) D. Hairy leukoplakia E. Reverse transcriptase F. CD8 G. Kaposi's sarcoma H. gp120 I. CD4 J. CD25 K. MIP-1alpha L. Anti-HIV antibody (Western blot) M. Integrase
- A 43-year-old man with a known history of HIV presents to his doctor with creamy plaques coating his tongue and oral cavity. His symptoms subside after treatment with fluconazole.
- A 37-year-old woman with a past history of intravenous drug use presents to her GP for her methadone prescription. On examination they note pale rigid lesions on the side of her tongue. Alongside her methadone the GP prescribes aciclovir.
- In addition to CD4+ T-lymphocyte counts, HIV monitoring is typically assessed through which measurement?
- Which of the above is a naturally occurring cytokine that is able to inhibit HIV fusion to CD4+ T-lymphocytes?
- Which viral protein is responsible for the binding or fusion of HIV to human CD4+ T-lymphocytes?
- Correct B. Candidiasis
- Correct D. Hairy leukoplakia
- C, Viral load PCR
- Correct K. MIP-1alpha
- Correct H. gp120
A. Influenza B. MMR C. BCG D. Meningococcal E. Varicella-Zoster F. Diptheria G. Pertussis H. Tetanus I. Measles J. Hepatitis B K. Rabies
- Vaccine given at 12 – 18 months to prevent otitis media, parotitis, and cataracts in patients.
- An immunocompromised HIV positive patient should not receive this vaccine.
- Haemophiliacs and patients in receipt of regular blood transfusions should be vaccinated against this virus.
- Toxoid given as part of ‘triple’ vaccine during first year of life to prevent cardinal features of the disease: muscle spasms and rigidity.
- Vaccine recommended for high risk patients with chronic respiratory diseases, but contraindicated in patients hypersensitive to eggs.
- Correct B. MMR
- Correct C. BCG
- Correct J. Hepatitis B
- Correct H. Tetanus
- Correct A. Influenza
KILLED, Viral Influenza Hep A IM polio rabies Japanese B encephalitis Tick borne encephalitis
KILLED, bacterial Vibrio cholerae Yersinia pestis Rickettsia rickettsiae Coxiella burnettii Bacillus anthracis
Live attenuated, viral MMR VZV Oral polio rotavirus yellow fever virus Live attenuated, bacterial BCG oral Salmonella typhi Francisella tularensis
Live vaccine mnemonic: MOBY= MMR, Oral polio/tyhpi, BCG, yellow fever,
Recombinant, viral
Hep B
Human Papilloma virus
Conjugated/subunit, bacterial
Hib
Men C conjugate
Men ACWY (polysaccharide only)
Pneumococcal Conjugate Vaccine: 7 valent (PRevenar)
Pneumococcal polysaccharide only: 23 valent (Pneumovax)
Bordetella pertussis (acellular, component)
IM Salmonella typhae
Toxoids
Corynebacterium diphtheriae
Clostridium tetani
Bordetella pertussis (acellular, component)
A. Rifampacin B. Linezolid C. Flucloxacillin D. Vancomycin E. Penicillin V F. Erythromycin G. Gentamicin H. Metronidazole I. Cefuroxime/Ceftriaxone J. Trimethoprim K. Ciprofloxacin L. Isoniazid M. Cefuroxime & clarithromycin
- Community-acquired UTI
- C.difficile colitis where metronidazole has failed
- Severe systemic infection before cause has been identified
- Atypical pneumonia caused by Legionella in individuals with penicillin allergy
- Long-term prophylactic treatment for post-splenectomy patients
- 75 year old female has been diagnosed with MRSA bacteraemia secondary to an infected leg ulcer.
- Treatment of an 18 year old with Meningitis.
- 35 year old household wife presents with an infected insect bite. In the past she has been treated with Penicillin and responded with facial swelling and acute shortness of breath.
- Patient with an abdominal collection that contains gram –ve anaerobes.
- 56 year old male with endocarditis caused by VRE.
- An 82 yr old gentleman, living at home, develops severe dyspnoea with a productive cough and fever. His PaO2 has fallen below 8kPa, and he is becoming confused.
- A 6 month old child whose father has just been diagnosed with tuberculosis.
- A 12 yr old boy requests treatment for widespread impetigo. He developed an urticarial rash 3 yrs ago when he was given penicillin V.
- Correct J. Trimethoprim
- Correct D. Vancomycin
- Correct I. Cefuroxime
- Correct F. Erythromycin
- Correct E. Penicillin V
- Correct D. Vancomycin
- Correct I. Ceftriaxone
- Correct F. Erthyromycin
- Correct H. Metronidazole
- Correct B. Linezolid
- Cefuroxime & clarithromycin
- Correct L. isoniazid
- Correct F. Erthyromycin
A. Aeromonas B. Yersinia C. Clostridium difficile D. Escherichia Coli E. Entamoeba histolytica F. Vibrio cholera G. Hepatitis A H. Salmonella I. Shigella J. Ulcerative Colitis K. Campylobacter L. Staph aureus
- This microbe is spread by faecal-oral route, and often occurs in epidemics. Shellfish from seawater contained by sewage can harbour this microbe.
- Gram-negative curved rod, whose toxin affects adenyl cyclase. Its major cause of death is shock, metabolic acidosis and renal failure.
- This microbes affects mainly the distal colon, producing acute mucosal inflammation and erosion. It is spread by person-to-person contact, and its clinical features include fever, pain, diarrhoea and dysentery.
- Infection with this microbe produces pseudomembranous colitis.
- This microbe affects the ileum, appendix and colon. Its peyer patch invasion leads to mesenteric lymph node enlargement with necrotising granulomas. Complication can include peritonitis, pharyngitis and pericarditis.
- A 40 year old female, who is a ex-smoker, who has recently returned from a holiday in India, comes to A+E complaining of severe abdominal cramps and bloody diarrhoea. She mentions that her mother suffered from similar symptoms in the past.
- Following a barbeque, a 41 year old develops watery diarrhoea and vomiting. On retrospect, he wondered whether he should have had that dodgy looking shish kebab…
- Mrs A became ill at about midnight after eating chicken wings for lunch at a summer BBQ. Mrs A complained of nausea, vomiting and non-bloody diarrhoea. Her symptoms resolved 3 days later.
- Mr S became ill with nausea, vomiting and watery diarrhoea about 4 hours after eating some ham at a conference buffet lunch. Mr B’s illness was attributed to a heat stable, preformed toxin in the ham. His symptoms resolved within 24hours.
- Mr C complained of fever and severe (>10 bowel movements/day) diarrhoea after looking after his neighbours dogs for a few days. Laboratory analysis of Mr C’s stools found the causative organism to be a S-shaped microaerophillic bacteria.
- Different geographical populations of this organism often give rise to traveller’s diarrhoea
- Correct G. Hepatitis A (could also be cholera)
- Correct F. Vibrio cholera
- Correct I. Shigella
- Correct C. Clostridium difficile
- Yersinia enterocolitica undergoes multiplication in Peyer’s patches following invasion of human epithelial cells and penetration of the mucosa which occurs in the ileum. Complications include diarrhoea, mesenteric adenitis, mesenteric ileitis, or acute pseudoappendicitis, reactive arthritis and erythema nodosum.
- Correct J. Ulcerative colitis
- H, Salmonella
- H, Salmonella
- L, Staph
- K, Campylobacter
- D, E coli
