Microbio Flashcards
The antiviral which is given to untreated pregnant women with HIV to prevent vertical transmission of the virus during childbirth.
Nevirapine (NNRTI).
Is more effective that ZDV when given as a stat dose in childbirth.
Zidovudine can be given as monotherapy in pregnancy or in combination with Nevirapine and lamivudine.
An immunomodulatory therapy used in the treatment of hepatitis B.
Interferon-alpha.
Hep B is not treated with intereferon B
The final metabolite of the antiviral used to treat Herpes Simplex
Aciclovir triphosphate.
Resistance develops when viral tyrosine kinases mutate to reduce aciclovir to a monophosphate.
An antiviral which can be used in aerosol form to prevent respiratory syncytial virus in children with heart and lung disease
Ribavirin
The synthetic nucleoside analogue ganciclovir is the drug of choice against which infective virus?
CMV
Valaciclovir, a prodrug of aciclovir, is used to treat patients with which viral disease in the list, above?
VZV
Used for the treatment of severe, resistant herpes infections
Foscarnet - DNA polymerase inhibitor.
A drug that is effective against influenza A but not influenza B
Amantadine
A purine nucleoside analogue that selects specifically for thymidine kinase
Aciclovir
A nucleoside analogue which inhibits reverse transcriptase
Zidovudine
The drug mechanisms which acts by stopping post-translational cleaving of polyproteins by inhibiting proteases
Indinavir, Nelfinavir, Ritonavir - anything ending *navir.
The drug that is selectively toxic to virally infected cells through its selective phosphorylation using viral thymidine kinase
Aciclovir
The drug which can be delivered by inhalation to treat both influenza A and B.
Zanamivir, Oseltamivir
Ending *mivir.
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.
Mycoplasma pneumonia
Dry cough, new infiltrates on CXR, dyspnoea and target shaped lesions on the palms. No recent history of herpes.
Mycoplasma pneumonia
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.
MSSA - because being given a macrolide.
Macrolides are the drug of choice in legionella and mycoplasma, camplylobacter.
A 55 year old female clown, recovering from a cold, is found to have a cavitating lesion on CXR and a productive cough.
Flu is a classic precedent of S. aureus pneumonia. S. aureus pneumona produces cavitating lesions on CXR.
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.
Burkhoderia cepacia
A 25 year old man with a latex allergy comes into GUM clinic with small grouped vesicles and papules on the shaft and glans of his penis. This was accompanied with severe pain in his groin, buttocks and upper thighs, a fever, and dysuria. Virology showed the presence of an alpha herpesvirus, HHV 2
Primary genital herpes
A 21 year old man came to hospital complaining of severe headache, fever, malaise and a sore throat. On examination he showed cervical lymphadenopathy, especially the posterior cervical nodes, and splenomegaly. Peripheral blood tests showed the presence of lymphocytosis with atypical mononuclear cells. The Paul Bunnell reaction was positive for heterophilic antibiodies.
Glandular fever, EBV
HSV1 is commonly assoc with
Primary stomatitis
CMV is commonly assoc with
Pneumonitis
HSV2 is commonly assoc with
Neonalta infection associated with vaginal delivery.
HHV8 is commonly assoc with
Kaposis sarcome
HHV6 is commonly assoc with
roseola infantum (Exanthem subitum)
Pneumonitis after a bone marrow transplant
CMV (beta)
Endemic Burkitt’s lymphoma
EBV (gamma)
Acute necrotising encephalitis
HSV1 (alpha)
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.
Candidiasis
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.
hairy Leukoplakia
Naturally occurring cytokine that is able to inhibit HIV fusion to CD4+ T-lymphocytes?
MIP-1a, MIP-1b and RANTES
Which viral protein is responsible for the binding or fusion of HIV to human CD4+ T-lymphocytes?
gp120
An immunocompromised HIV positive patient should not receive this vaccine.
BCG
75 year old female has been diagnosed with MRSA bacteraemia secondary to an infected leg ulcer.
Vancomycin
Treatment of an 18 year old with Meningitis
Ceftriaxone
Patient with an abdominal collection that contains gram –ve anaerobes.
Metronidazole
56 year old male with endocarditis caused by VRE.
Linezolid
C.difficile colitis where metronidazole has failed
Vancomycin
Atypical pneumonia caused by Legionella in individuals with penicillin allergy
Erythromycin
Severe systemic infection before cause has been identified
Cefuroxime
Long-term prophylactic treatment for post-splenectomy patients
Penicillin V
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.
cefuroxime and clarithromycin
A 6 month old child whose father has just been diagnosed with tuberculosis.
isoniazid
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.
Shigella
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.
Yersinia
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.
A 34 year old female returned from Indonesia two weeks ago. She complains of diarrhoea, abdominal pain, weight loss, nausea and vomiting for the past few days. She has no fever. Investigation reveals steatorrhoea and stools appear to contain numerous cysts.
Giardiasis
Following a trip to Brazil, a patient develops bloody diarrhoea, with a high fever, sweating and on examination the patient is found to have RUQ pain.
Entamoeba Histolyticia.
Ingestion of Entamoeba histiolytica cysts is followed by excystation in the small bowel and trophozite colonisation of the small colon. The trophozyte may then encyst and be excreted in faeces or it may invade the intestinal mucosal barrier, thereby gaining access to the circulation. Complications include amoebic colitis, liver abscesses, pleuropulmonary amoebiasis and cerebral amoebiasis.
A 40 year old homosexual man develops severe flatulence, accompanied by bloating and explosive diarrhoea.
Giardia (but could be entamoeba)
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.
Salmonella (duration too long for Brucella)
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.
Bacillus Cerus
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.
Campylobacter
Miss D initially complained of a dry mouth and visual disturbance a few days after ingesting some home canned produce. She sought medical attention after she began to experience bilateral descending paralysis. Miss A later died from respiratory failure.
Clostridium botulinum
Cause of bubonic plauge
Yeersinia pestis
A student who presented with two day history of bloody diarrhoea, vomiting, fever, headache and myalgia. He has just returned from camping in the country side near a farm where he had fresh cow’s milk for breakfast everyday.
Campylobacter
A 2 year old boy living in the slums who has a one day history of profuse watery diarrhoea, fever and abdominal cramps. His family’s main source of water is the river near their squatters
Cryptosporidium parvum -
Parasitic disease of mammalian intestinal tract. Usually immunocompromised. Profuse diarrhoea with anorexia, nausea and vomiting, with adbo pain.
Can cause cryptosopridosis of lungs, hepatitis and cholecystitis
A man was bitten by a rat in Asia. Ten days later he complains of fever, malaise, headache and myalgia.
Siprillium minus - gram negative
Associated with rat-bite fever.
Cat-scratch disease
Bartonella henselae (or bartonella species)
A zoonosis associated with hepatitis, jaundice, conjunctival injection and renal impairment. Transmission normally occurs by direct contact with either the urine or tissues of an infected animal.
Leptospirosis (associated with rat urine in water). Corkscrew shaped bacteria
Myalgia, conjunctivits, hepatitis, renal failure.
Combination of jaundice and renal failure is Weil’s disease.
Treat with penicillin.
A 22 year old student, who returned from a holiday in the Mediterranean 3 weeks ago, presents with an undulant fever, malaise, weakness and generalized bone pain. Upon examination lymphadenopathy and hepatosplenomegaly are also noted.
Brucellosis
A 45 year old male farmer presents with a raised, erythematous rash, with clearing in the centre. He also complains of headache, fever, athralgia and malaise.
Lyme disease - rash is erythema migrans (immune mediated rash at site of the bite).
A 30 year man presented with jaundice and conjunctival haemorrhages. He had recently been canoeing in the US and had felt ‘run-down’ upon his return to the UK.
Leptospira interrogans
A 25 year old Maltese man presented to his GP with lethargy for a month and headaches and fever. On examination, he had a temperature of 39°C and one fingerbreadth splenomegaly. Small Gram-negative coccobacilli were seen on culture in Casteneda’s medium.
Brucella melitensis (Gram negative rod)
Associated with malta (maltese fever). From unpasteruised milk
Undulating fever with with muscle pain. Can cause hepatitis and neuro disorders.
A 22 year old student presented to her GP upon return from a biology field trip, with a lesion on her leg which was 3” in diameter and flat, with a red edge and dim centre. She also mentioned feeling tired and suffering from headaches. On examination, the GP noted a fever of 38.0°C and an irregular heartbeat.
Borrelia burgdorferi (causative organism of Lyme disease).
A tanner on holiday from India presented to hospital with an ulcerating papule on his hand. On inspection of the ulcer, the centre was black and necrotic. Gram-positive rods grew on blood agar culture and responded to treatment with large doses of penicillin.
Bacillus anthraticus