Infectious Disease Flashcards
Pneumonia + blood smear (red cell agglutination) - organism?
Mycoplasma pneumoniae
IgM ab against the bug react against RBCs at cold temp -> haemolytic anaemia
Why do you get continuous motor spasms with tetanus toxin (tetanospasmin)?
Blockage of inhibitory neurotransmitters GABA and Glycine
Pruritic rash on the buttocks or soles
GI - diarrhoea + abdo pain / bloating
Organism? method of infection?
Strongyloides stercoralis - penetrates the skin
How do penicillins and cephalosphorins work?
Inhibit cell wall formation (beta-lactams)
Mx of Leigonella?
Macrolides - erythromycin / clarithromycin
Measles transmission?
Aerosol transmission
Mx of chlamydia? what if pregnant?
7d Doxycycline (If CI Azithromycin)
If pregnant:
- Azithromycin, erythromycin or amoxicillin
A history of Intravenous drug use coupled with a descending paralysis, diplopia and bulbar palsy is characteristic of infection with ……
Clostridium botulinum
Mx of UTI in pregnancy?
Nitro unless close to term
What are the features of Japanese encephalitis?
Headaches, fever, seizures and confusion
Parkinsonian features suggest basal ganglia involvement
Can also present with flaccid paralysis
Mx of C. Jejuni infection?
Clarithromycin
What medication should should all patients with CD4 <200/mm3 recieve?
Prophylaxis against Pneumocys
What are some characteristic features of pneumococcal pneumonia? (strep pneumo)
rapid onset
high fever
pleuritic chest pain
herpes labialis (cold sores)
Ciprofloxacin increases the risk of which infection?
MRSA
Draw and learn the Gram +ve bacteria diagram
Yes please!
Bilateral conjunctivitis, bilateral calf pains and high fevers in a sewage worker
Organism? mx?
Leptospirosis
Mx: High dose benzylpenicillin / doxycycline
Trypanosoma cruzi, causes what disease? what is the most frequent and severe complication? other complications?
Chagas disease
Dilated cardiomyopathy (due to myocarditis + can also have arrhythmias)
GI features - Megaoesophagus + Megacolon -> constipation and dysphagia
Investigations for Lyme disease?
ELISA 1st
If +ve or equivocal -> immunoblot test (western blot)
gram-negative diplococci that can be identified on gram staining
Organism?
Neisseria gonorrhoea
What can occur in lung cavity from prev TB?
Aspergilloma
How do macrolides work? What are some adverse effects?
Inhibit the 50S subunit of ribosomes
Adverse:
- Nausea (esp erythromycin)
- P450 inhibitor
- Prolonged QT interval
Most common cause of bladder calcification? mx?
Schistosomiasis is the most common cause of bladder calcification worldwide
Schistosoma haematobium causes haematuria
mx: single oral dose of praziquantel
Which vaccines are live attenuated and hence CI in those on immunosupressive therapy
BCG
measles, mumps, rubella (MMR)
influenza (intranasal)
oral rotavirus
oral polio
yellow fever
oral typhoid
vaginal discharge: offensive, yellow/green, frothy
vulvovaginitis
strawberry cervix
pH > 4.5
in men is usually asymptomatic but may cause urethritis
Suggestive of which organism infection? mx?
Trichomonas vaginalis
Mx: oral metronidazole 5-7d or 1 dose 2g
Most common cause of central line infections?
Staph epidermis
Features of severe malaria falciparum?
Feature of severe falciparum malaria
schizonts on a blood film
parasitaemia > 2%
hypoglycaemia
acidosis
temperature > 39 °C
severe anaemia
complications as below
Complications
cerebral malaria: seizures, coma
acute renal failure: blackwater fever, secondary to intravascular haemolysis, mechanism unknown
acute respiratory distress syndrome (ARDS)
hypoglycaemia
disseminated intravascular coagulation (DIC)
Which bacteria are gram +ve cocci and which are gram -ve cocci?
Gram-positive cocci = staphylococci + streptococci (including enterococci)
Gram-negative cocci = Neisseria meningitidis + Neisseria gonorrhoeae, also Moraxella catarrhalis
Which bacteria are Gram +ve rods (bacilli)
mnemonic = ABCD L
Actinomyces
Bacillus anthracis (anthrax)
Clostridium
Diphtheria: Corynebacterium diphtheriae
Listeria monocytogenes
Some examples of Gram -ve rods?
CHESS P
Campylobacter jejuni
Haemophilus influenzae
Escherichia coli
Salmonella sp.
Shigella sp.
Pseudomonas aeurginosa
black eschar that is typically painless
Organism / infection? mx?
Anthrax - Bacillus anthracis
Mx: Ciprofloxacin
What is an alternative for PCP mx? Issues with this?
Aersolised pentamidine - less effective and risk of pneumothorax
Most commonly isolated organism from animal bites?
Pasteurella multocida
What is Q fever caused by? how does this present?
Coxiella burnetti
No rash but causes pneumonia
Gram+ve organism in clusters
Coagulase -ve
Causes UTI - which group esp?
Esp in young sexually active women
Staph saprophyticus
What can cause IDA in patients returning from travel to endemic regions (eg indian subcontinent)
Hookworms
Retro-orbital headache, fever, facial flushing, rash, thrombocytopenia in returning traveller
Diagnosis?
Dengue
Abx of choice for animal bites?
Co-amox
What malignancies are associated with EBV?
Burkitt’s lymphoma
Hodgkin’s lymphoma
nasopharyngeal carcinoma
What does atypical lymphocytes on blood film suggest?
Glandular fever
What is Kaposi sarcoma caused by?
HHV-8 (human herpes virus 8)
Describe LP findings in Viral meningitis:
Opening pressure -
Cell count -
Cell differential -
Glucose -
Protein -
Opening pressure - normal
Cell count - raised
Cell differential - Lymphocytes
Glucose - Normal / 2/3 of serum levels
Protein - within normal range / raised
depigmentation and loss of sensation
Infectious cause?
Leprosy
Gram-positive cocci in clusters, which are coagulase positive
Organism?
Staphylococcus aureus
Mx of toxoplasmosis inn immunocompromised patients?
pyrimethamine plus sulphadiazine
Abx recommended for animal and human bites?
Co-amox
What are some examples of live attenutated vaccines which should be not recommended for those with weakened immune systems?
MY BOOTI
MMR
Yellow
BCG
Oral poilo
Oral rotavirus
Typhoid oral
Influenza intranasal
Severe vomiting
Short incubation period
suggestive of which cause of gastroenteritis?
Staph aureus
Hep E - risk is associated with what? how is it spread?
Faecal-oral spread, commonly affecting shellfish and pork products
Mx of PCP?
co-trimoxazole
IV pentamidine in severe cases
aerosolized pentamidine is an alternative treatment for Pneumocystis jiroveci pneumonia but is less effective with a risk of pneumothorax
steroids if hypoxic (if pO2 < 9.3kPa then steroids reduce risk of respiratory failure by 50% and death by a third)
Why is primaquine used in mx of non-falciparum malaria?
Destroy liver hypnozoites and prevent relapse
Mx of Lyme disease?
Doxycycline if early disease - amox if CI eg pregnancy
Ceftriaxione if disseminated disease
lower back pain, fever, myalgia, fatigue, jaundice and a subconjunctival haemorrhage.
in a sewage worker - suggestive of which disease?
Leptospirosis
Mx of mycoplasma pneumonia?
Mycoplasma pneumonia - treat with doxycycline or a macrolide
What is the most effective single step to reduce the incidence of MRSA?
Hand hygiene
Most important ix to exclude HIV seroconversion?
p24 antigen test
Severe joint pain + high fever after returning from Africa / asia / indian subcontinent?
Chikungunya
How must live vaccines be given? (time period in between)
Live vaccines given by injection may be either given concomitantly or a minimum interval of 4 weeks apart to prevent risk of immunological interference
Mx of pubic lice?
application of either: malathion 0.5%, permethrin 1%, phenothrin 0.2% or carbaryl 0.5%
All of these creams or lotions are applied to all body hair and left on the hair for the recommended ‘treatment time’ before being washed off.
Treatment should be re-applied after 3-7 days: this is due to the presence of lice and eggs being at different stages of their life cycle.
Re-examination 1 week after this
Which organism can present with culture -ve endocarditis? mx?
Coxiella burnetti
Mx - doxycycline
What is non-specific (non-gonococal) urethritis? mx?
common presentation where inflammatory cells but no gonococcal bacteria are seen on swab
Tx - Doxycycline / Azithromycin
Triad of disseminated gonoccal infection?
Tenosynovitis
Migratory polyarthritis
Dermatitis
MoA of botulinim toxin?
Botulinum toxin inhibits the release of acetylcholine at synapses
What are the features of typhus?
Mx?
fever, headache, malaise
rash
- typically maculopapular
- begins on the trunk and spreads to the extremities
later complications
- meningoencephalitis
Mx: Doxycycline
Which infection typically presents as: flu like illness → brief remission→ followed by jaundice and haematemesis
Yellow fever
Which species of malaria has shortest replication cycle - what does this mean in practice?
P. knowlesi has the shortest erythrocytic replication cycle, leading to high parasite counts in short periods of time
Normal causes of genital ulcers, painful and painless
painful: herpes much more common than chancroid
painless: syphilis more common than lymphogranuloma venereum (painful lymphadenopathy less likely in latter)
HIV drugs and their MOAs?
NRTIs end in ‘ine’ (Nucleoside analogue reverse transcriptase inhibitors)
PIs: end in ‘vir’ (Protease inhibitor)
NNRTIs: nevirapine, efavirenz (Non-nucleoside reverse transcriptase inhibitors)
Common complications of PCP pneumonia?
Pneumothorax
Aciclovir MoA?
DNA polymerase inhibitor
Patients with hyposplenism should be vaccinated against which disease?
pneumococcal, Haemophilus type B and meningococcus type B+C
Annual influenza
Infection following renal transplant is most commonly caused by?
CMV
What is the typical signs of infection with mycobacterium marinum?
Fish tank granuloma - 3-4w incubation and leisons can be painful or painless
If there is a skin break can lead to systemic spread (sporotrichoid spread)
Tx can include- Tetracyclines, fluoroquinolones, sulfonamides and macrolides
Can you breast feed with HIV?
No regardless of viral count
Neonatal ART in HIV?
zidovudine is usually administered orally to the neonate if maternal viral load is <50 copies/ml.
Otherwise triple ART should be used.
Therapy should be continued for 4-6 weeks.
Delivery of babies in mothers with HIV?
vaginal delivery is recommended if viral load is less than 50 copies/ml at 36 weeks, otherwise caesarian section is recommended
a zidovudine infusion should be started four hours before beginning the caesarean section
What is thick and thin blood films used for?
Thick blood films check for parasite burden
Thin films allow for speciation
Severe hepatitis in a pregnant woman
What organism?
Hep E
Fever and the presence of a eschar in a patient returning from South East Asia is strongly suggestive of
What infection and tx?
scrub typhus (caused by Orientia tsutsugamushi) and necessitates urgent treatment with doxycycline
Relative CI for donepezil ?
Bradycardia eg sick sinus syndrome
Can you use memantine in mild dementia?
No reserved as 2nd live tx and at least moderate
What are some RFs for pressure ulcers?
malnourishment
incontinence: urinary and faecal
lack of mobility
pain (leads to a reduction in mobility)
Schistosoma haematobium is most strongly associated with what ca?
Schistosomiasis is a risk factor for
Squamous cell bladder cancer
For non-falciparum malaria: mx?
For non-falciparum malaria:
in areas which are known to be chloroquine-sensitive then WHO recommend either an artemisinin-based combination therapy (ACT) or chloroquine
in areas which are known to be chloroquine-resistant an ACT should be
If a sexually active patient presents with genital chlamydia and bowel symptoms
What should be considered? tx?
LGV proctocolitis - presents with tenesmus, rectal bleeding, and discharge. LGV is particularly prevalent among men who have sex with men and requires targeted treatment, typically with a prolonged course of doxycycline.
Mx of genital warts?
multiple, non-keratinised warts: topical podophyllum (imiquimod is a topical cream - used 2nd line)
solitary, keratinised warts: cryotherapy
Mx of Severe falciparum malaria?
intravenous artesunate
if parasite count > 10% then exchange transfusion should be considered
shock may indicate coexistent bacterial septicaemia - malaria rarely causes haemodynamic collapse
(Parasite count >2% usually needs paraenteral tx regardless of clinical picture)
Most common complication of Gonorrhoea infection?
Infertility secondary to PID
Most common causes of PID?
- Chlamydia
- Gonorrhoea
When should vaccination occur for splenectomy and what about abx prophylaxis
if elective, should be done 2 weeks prior to operation
Pen V prophylaxis - at least 2 years and until they’re 16 but often lifelong
What should be provided in non-falciparum malaria after acute mx + why?
Primaquine - destroys liver hypnozoites + prevents relapse
When should asuymptomatic bacteriuria be treated?
in pregnancy, children younger than 5 years or immunosuppressed patients due to the risk of complications
Which organisms cause endemic and epidemic typhus
Rickettsia typhi is the organism causing endemic typhus.
Rickettsia prowazekii is the organism causing epidemic typhus.
What is the first step in suspected Lyme disease without erythema migrans?
ELISA test
What ix is used to identify fungi in tissue samples eg PCP?
silver stain
Mx of Chagas disease (Trypanosoma cruzi)
treatment is most effective in the acute phase using azole or nitroderivatives such as benznidazole or nifurtimox
Non-bloody diarrhoea, bloating, weight loss +- malbsorption / lactose intolerance
Which organism + mx?
Giardasis - giardia lamblia
Tx - metronidazole
Cutaneous larva migrans (CLM)
mx?
Thiabendazole
Gram-positive rod (bacilli) causing meningitis?
Listeria monocytogenes
Cutaneous leishmaniasis requires treatment when?
cutaneous leishmaniasis acquired in South or Central America merits treatment due to the risk of mucocutaneous leishmaniasis whereas disease acquired in Africa or India can be managed more conservatively
Shigella mx?
Usually supportive but:
antibiotics (e.g. ciprofloxacin) are indicated for people with severe disease, who are immunocompromised or with bloody diarrhoea
What are the main complications of chronic chagas?
myocarditis (biggest cause of mortality) may lead to dilated cardiomyopathy (with apical atophy) and arrhythmias
gastrointestinal features includes megaoesophagus and megacolon causing dysphagia and constipation
most common bacterial cause of pharyngitis (sore throat) in children and young adults is what?
Strep pyogenes
Opisthotonus - what is this and when is it seen?
state of a hyperextension and spasticity in which a patient’s neck and spinal column enter into an arching position
Seen in tetanus due to spasm of axial muscles
Tetans mx:
Patient has had a full course of tetanus vaccines (5), with the last dose < 10 years ago -no vaccine nor tetanus immunoglobulin is required, regardless of the wound severity
Patient has had a full course of tetanus vaccines, with the last dose > 10 years ago
if tetanus prone wound: reinforcing dose of vaccine
high-risk wounds (e.g. compound fractures, delayed surgical intervention, significant degree of devitalised tissue): reinforcing dose of vaccine + tetanus immunoglobulin
If vaccination history is incomplete or unknown
reinforcing dose of vaccine, regardless of the wound severity
for tetanus prone and high-risk wounds: reinforcing dose of vaccine + tetanus immunoglobulin
mx of different levels of anti-HBs (Hep B)
> 100 Indicates adequate response, no further testing required. Should still receive booster at 5 years
10 - 100 Suboptimal response - one additional vaccine dose should be given. If immunocompetent no further testing is required
< 10 Non-responder. Test for current or past infection. Give further vaccine course (i.e. 3 doses again) with testing following. If still fails to respond then HBIG would be required for protection if exposed to the virus
How to distinguish between different types of inguinal lymphadenopathy and genital ulcer
Inguinal Lymphadenopathy is present in Syphilis, LGV and Chancroid
1. Painless IL + Painless ulcer - Syphilis
2. Painful IL + Painless ulcer - LGV
3. Painful IL + Painful ulcer - Chancroid
ChanCRIED in pain
SyphiLESS (painless)
LGV mix (starts with lymph so this is the painful bit)
Why can TB lead to low Na, raised K and hypotension?
M. tuberculosis can cause hypoadrenalism
- check serum cortisol
Which vaccines to avoid with egg allergy
●● Influenza
●● Tick-borne encephalitis
●● Yellow fever
●● Hepatitis A
What type of reaction is caused by tuberculin skin tests? What is this mediated by?
Type IV hypersensitivity (delayed)
Mediated by inteferon gamma by th1 cells -> macrophage activation
How is amoebic dysentery investigated?
stool microscopy may show trophozoites if examined within 15 minutes or kept warm (known as a ‘hot stool’)
Mx of amoebic dysentry?
Oral metronidazole
a ‘luminal agent’ (to eliminate intraluminal cysts) is recommended usually as well e.g. diloxanide furoate
What is immune reconstitution inflammatory syndrome?
Condition associated w HIV / immunosuppression
Occurs when the immune system begins to recover, but then responds to a previously acquired opportunistic infection with an overwhelming inflammatory response that paradoxically makes the symptoms of infection worse.
Mantoux test interpretation?
Diameter of induration
< 6mm = Negative - no significant hypersensitivity to tuberculin protein Previously unvaccinated individuals may be given the BCG
6 - 15mm = Positive - hypersensitive to tuberculin protein, Should not be given BCG. May be due to previous TB infection or BCG
> 15mm = Strongly positive - strongly hypersensitive to tuberculin protein Suggests tuberculosis infection.
Causes of false -ve mantoux test?
miliary TB
sarcoidosis
HIV
lymphoma
very young age (e.g. < 6 months)
ART suffix gravir - what is the mechanism?
Integrase inhibitors (‘gravirs’) - blocks the enzyme that inserts the viral genome into the DNA of the host cell
ART suffix ‘navir’ MoA? which one is a potent inhibitor of P450 system?
Protease inhibitors (PI)
Ritonavir - potent inhibtor of P450
nevirapine, efavirenz
are examples of what type of medication?
ART - Non-nucleoside reverse transcriptase inhibitors
zidovudine (AZT), abacavir, emtricitabine, didanosine, lamivudine, stavudine, zalcitabine, tenofovir
Are all examples of what class of ART? general side effect associated?
Nucleoside analogue reverse transcriptase inhibitors (NRTI)
Generally associated with peripheral neuropathy
Mx of meningeal tb?
RIPE for prolonged period (at least 12 months)
+ Steroids
TV v BV discharge colour
BV - grey white
TV - green frothy
What is filariasis commonly caused by? what does this cause?
W. Bancrofti
Leads to lymphatic obstruction
usually diagnosed w blood smear
tx = diethycarbamazine
Is there a Hep C vaccine and can you treat it?
No vaccine but treatment is successful in majority
Mx of campylobacter gastroenteritis in immunocompromised patients?
Supportive + clarithromycin (cipro also possible but frequently)
Describe what is Monod sign and what is it suggestive of?
a mass within a cavity with a ‘Monod sign’ (the crescent of the surrounding air)
Suggestive of aspergiloma
Possible complications of diptheria?
neuritis e.g. cranial nerves
heart block
Signs of severe campylobacter that warrants abx therapy?
Immunocompromised pt
High fever
Bloody diarrhoea
8+ stools /day
What does leucocyte +ve and nitrite -ve tell us about in a urine dip
Gram negative organisms test positive on the nitrite test as they convert nitrates to nitrites for energy
Hence must be gram +ve - eg strep / staph
BM aspirate showing - macrophages with amastigotes - dx? mx?
Dx = Visceral leishmaniasis
mx: Sodium stibogluconate
How to distinguish between Hep B + co-infection / superinfection of Hep D
The presence of Anti-HD IgM in the recent blood test suggests an acute Hepatitis D infection
If this occurs same time as Hep B infection this is co infection however if occurs later this is superinfection
HIV causes of pneumonia and distinguishing?
Pneumonia+ HIV+ few chest signs+Bilat infiltrates = PCP
Pneumonia+ HIV+ typical features = Strep pneumoniae
What are bacterial exotoxins mainly produced by?
Gram +ve bacteria
cyclical fever with a 24-hour interval - which parasite?
Plasmodium knowlesi malaria - due to short replication cycle
Ongoing sx despite tx w im ceftriaxone for gonorrhoea suggests what?
Coexistent chlamydia
non-offensive discharge + easily bleeding - what dx?
Chlamydia treated w doxycycline
Black eschar how to distinguish causes?
WITHOUT travel to endemic regions + oedema = Cutaneous anthrax
travel to endemic regions + WITHOUT oedema = Can be due to rickettsia
CXR in Leigonella? what other features may be seen?
Bilateral, mid-to-lower zone patchy consolidation in an older patient often
Can also include dry cough, relaltive bradycardia and LFT derangement
Man returns from trip abroad with maculopapular rash and flu-like illness
think what dx?
HIV seroconversion
What is a Jarisch Herxheirmers reaction and how can it be distinguished from anaphylaxis? tx?
fever, rash, tachycardia after the first dose of antibiotic
in contrast to anaphylaxis, there is no wheeze or hypotension
it is thought to be due to the release of endotoxins following bacterial death and typically occurs within a few hours of treatment
mx:
no treatment is needed other than antipyretics if required
NB can be seen with syphilis
limited number of skin lesions, hypaesthesia and hair loss
Presence of thickened cord-like structures that are tender
Describes what condition??
Tuberculoid leprosy
Mucocutaneous ulceration following travel?
dx?
Leishmania brasiliensis
rhabditiform larvae are diagnostic of which disorder and what is the mx?
Suggestive of strongyliodiasis
mx - Ivermectin or longer course of abendazole
fever, weight loss, massive splenomegaly and pancytopenia.
The additional clinical feature of ‘dark and ashen’ skin
Suggests which dx and organism?
Visceral leishmania secondary to Leishmania donovani
Mx of aspergilloma esp w significant haemoptysis?
Surgerical excision
most common symptoms seen in patients with visceral leishmaniasis?
pyrexia, splenomegaly (which is often massive), weight loss and night sweats.
Pancytopaenia occurs secondary to hypersplenism
Following a diagnosis of tetanus, what is the most appropriate antibiotic therapy to give with human tetanus immunoglobulin?
IV metronidazole
How to distinguish between c. botulinum v c. tetani paralysis
Clostridium botulinum - flaccid paralysis
Clostridium tetani - spastic paralysis
Cholera features and mx?
Profuse rice water diarrhoea, dehydration and hypoglycaemia secondary to gram -ve vibro cholerae
Mx = Oral rehydration therapy + doxycycline / cipro
Which men should be offered HPV vaccination?
HPV vaccination should be offered to men who have sex with men under the age of 45 to protect against anal, throat and penile cancers
Mx of leprosy?
WHO-recommended triple therapy: rifampicin, dapsone and clofazimine
RDC
What is the antibiotic of choice for treating meningococcal infection in patients with a known penicillin allergy, particularly when there is a history of anaphylaxis?
Chloramphenicol
Pneumococcal meningitis - How should the close contacts of this boy be managed?
No action unless cluster of cases
Common organisms involved with human bites?
Streptococci spp.
Staphylococcus aureus
Eikenella
Fusobacterium
Prevotella
Hep C result follownig acute infection?
15-45% of patients will clear the virus
55-85% will develop chronic hepatitis C
What does BCG protect against?
TB meningitis in children
unreliable in adults + doesnt protect well against pulmonary TB or primary infection
What is Lassa Virus and how is it spread?
Lassa virus is an example of viral haemorrhagic fever
Lassa fever is contracted by contact with the excreta of infected African rats (Mastomys rodent) or by person-to-person spread.
Testing of choice for salmonella typhoid fever?
Large volume blood culture
Diptheria effect on heart?
Can cause heart block
What is lemierres syndrome?
infectious thrombophlebitis of the internal jugular vein
often occurs secondary to a bacterial sore throat caused by Fusobacterium necrophorum leading to a peritonsillar abscess
Septic pulmonary emboli may also occur.
Mx of recurrent herpes in pregnancy?
Recurrent herpes outbreaks in pregnancy should be treated with suppressive therapy; risk of transmission to the baby is low and aciclovir is safe to use in pregnant women
What can acute toxoplasmosis present like in immunocompetent ppl?
Acute toxoplasmosis in the immunocompetent patient can mimic acute EBV infection (low-grade fever, generalised lymphadenopathy with prominent cervical lymph nodes and malaise) and should be suspected with negative EBV serology.
Pregnancy testing and counselling is paramount due to the risk of congenital toxoplasmosis
Post-exposure prophylaxis for HIV
oral antiretroviral therapy for 4 weeks
PID mx?
first-line: stat IM ceftriaxone + followed by 14 days of oral doxycycline + oral metronidazole
second-line: oral ofloxacin + oral metronidazole
Most specific test for meningococcal meningitis?
Blood PCR for meningococcus
Granuloma inguinale / Donovanosis cause?
Klebsiella granulomatis
What is the mechanism of action of amphotericin B?
Amphotericin B binds with ergosterol, a component of fungal cell membranes, forming pores that cause lysis of the cell wall and subsequent fungal cell death
What is the mechanism of action of thisTerbinafine?
Terbinafine inhibits the fungal enzyme squalene epoxidase, causing cellular death
How to remember the bacteriostatic abx?
Core medical trainee (to) Specialist trainee.. mneumonic for bacteriostatic
CORe - ChlORamphenicol
Medical - Macro
TRAinee - TeTRAcycline
to
SPecialty - SulPhonamide
TRaInee - TRImethoprim
Rest are bactericidal
A 25-year-old intravenous drug user with chronic hepatitis C becomes pregnant. Approximately what is the chance of the virus being transmitted to her child?
<10%
Management of african sleeping sickness African trypanosomiasis?
early disease: IV pentamidine or suramin
later disease or central nervous system involvement: IV melarsoprol
EBV class of virus?
Herpes virus
Enterotoxigenic Escherichia coli - can it cause bloody diarrhoea?
No but enterohemorrhagic Escherichia coli
Bloody diarrhoea causes?
Campylobacter
Ameaba
Shigella
E Coli
Trimethoprim effect on creatinine?
reversible increase in serum creatinine by competitively inhibiting the tubular secretion of creatinine without affecting glomerular filtration rate (GFR)
melioidosis - Burkholderia pseudomallei
mx?
Initial intensive therapy: IV ceftazidime, imipenem, or meropenem for 10-14 days
Followed by eradication therapy: oral TMP/SMX (plus doxycycline) for 3-6 months
Adjunct therapy: abscess drainage.
Mx of latent TB?
treatment for latent tuberculosis is 3 months of isoniazid (with pyridoxine) and rifampicin OR 6 months of isoniazid (with pyridoxine)
Post-exposure prophylaxis in Hep B?
booster dose should be given
How to distinguish TB v Cryptococcal meningitis in LP?
lymphocytic CSF with high protein and low glucose in this case could be due to both cryptococcal and TB meningitis,
however the insidious onset of symptoms, very high protein and low glucose compared to the plasma glucose (<1/3 of plasma) points more towards TB meningitis.
Mx of VZV pneumonia?
IV aciclovir
hep C testing?
Check for anti-HCV ab
oseltamivir moa?
Neuraminidase inhibitor
zanamivir what to be cautious of?
Bronchospasm risk
Estimates of transmission risk for single needlestick injury
Hep B, C and HIV
Hepatitis B 20-30%
Hepatitis C 0.5-2%
HIV 0.3%
What factor is most likely to increase the risk of transmission of HIV?
Mucosal ulceration
most common cause of visceral larva migrans?
Toxocara canis
Contraindicated in HIV-infected adults - vaccines?
Cholera CVD103-HgR
Influenza-intranasal
Poliomyelitis-oral (OPV)
Tuberculosis (BCG)
mx of cellulitis when pen allergic?
oral clarithromycin, erythromycin (in pregnancy) or doxycycline is recommended in patients allergic to penicillin
Is Hairy leukoplakia associated w EBV?
Yes
Gardnerella vaginalis bacteria type
Gram+ve coccobacili
