Infectious Disease 6

Question 1

Cranial nerve most affected in VZV?

Answer 1

Fifth nerve (trigeminal) - opthalmic branch

Question 2

VZV affects Fifth nerve - geniculate nucleus

Answer 2

Ramsay Hunt syndrome

Question 3

Rabies virus targets what?

Answer 3

Neurons via Acetylcholine receptor!

Question 4

congenital rubella syndrome features?

Rubella ( without congenital) features?

Answer 4

Sensorineural deafness
Congenital heart disease - PDA/pulmonary stenosis
Cataracts

Fever - eruptive descending rash - face to torso+ limbs

Question 5

What viruses are DNA?

Answer 5

Hep B, B19 parvovirus
CMV
VZV

Question 6

Commonest aspergillus species to cause disease in humans?

Answer 6

Fumigatus

Question 7

Histoplasmosis - has dual effect?

Answer 7

inside body = yeast

outside body = mould

Question 8

Histoplasmosis rare complication?

Answer 8

Mediastinal lymph nodes - inflamed and fibrosis

Ocular chorioretinitis

Question 9

Treatment for;
Mucormycosis
Histoplasmosis
Cryptococcus neoformans

Answer 9

Amphotericin B
(mucormycosis = echinocandins)

Question 10

Oral candidiasis in HIV/immunosuppressed patients - Treatment?

Answer 10

Oral fluconazole

Question 11

Antifungals that most ;
Nephrotoxic
Contraindicated in pregnancy, Long QT, agranulocytosis
Pancytopenia

Answer 11

Nephrotoxic = Amphotericin

Contraindicated in pregnancy, Long QT, agranulocytosis = Voriconazole

Pancytopenia = Flucytosine

Question 12

Special about Mycobacterium TB?

Answer 12

Lipid rich

Likes dry location, slow proliferation

Question 13

Extrapulmonary TB - most specific and sensitive test?

Answer 13

Pleural biopsy!!!

Question 14

Pyrazinamide MOA?

Answer 14

Intracellular acidification inside the granuloma

Question 15

Ethambutol MOA?

Answer 15

disrupt cell wall

Question 16

Why use moxifloxacin in TB?

Answer 16

To increase Rifampicin dose (synergistic effect)

Meningitis TB

Question 17

Treatment for MAC TB?

Answer 17

Macrolide - Azith/Clarith

RE for 12 months

Question 18

Cholera toxin does what?

Answer 18

Latch onto GM1 ganglioside - Increase cAMP - More CI - NA + H20 passively excreted - secretory diarrheal

Question 19

Commonest cause of Traveller’s diarrheal?

Answer 19

E. Coli ETEC 0157 strain

2nd commonest = shigellalosis

Question 20

Salmonella presentation and treatment?

Answer 20

Rose-coloured spot + bloody diarrheal + Intestinal perforation

Tx : Fluoroquinolones

Question 21

Borrellia spirochete causes?

Leptospira spirochete causes?

Answer 21

Borellia - Lyme disease

Leptospira - Leptospirosis

Question 22

Most severe form of Malaria?

Most highest mortality rate-form of Malaria?

Answer 22

P. Falciparum

P. Vivax

Question 23

Malaria parasites hides and grow where?

Answer 23

Hepatocytes -become Schizonts

Exo-erythrocytic phase

Question 24

Erythrocytic phase means?

Answer 24

Merozoites within schizonts rupture - infect more RBC

Question 25

Malaria mosquitoes picks up what?

Answer 25

Gametocytes - mature to become sporozoites in mosquito salivary gland

Question 26

P vivax and ovale - what significant about them?

Answer 26

Hyponozoites - dormant phase | Need Primaquine and again - 14 days later

Question 27

Fever pattern for malaria species; Falciparum vivax and ovale Malarie

Answer 27

Falciparum - continuous fever every 36 hours Vivax, ovale - Fever every 2nd day Malarie - Fever every 3rd day

Question 28

Prophylaxis malaria drug? Mekong area Everywhere else

Answer 28

Mekong - Atovaquone + Proguanil IF Severe form - Artemeter - Lumefantrine for extended period of time everywhere else Choloroquine

Question 29

When to use Tenofovir?

Answer 29

1st line + Co-infection with HIV + safest in pregnancy | + lamivudine resistance

Question 30

Interferon alpha not useful in what type of Hep B?

Answer 30

Pre-core mutant

Question 31

American Trypanosomiasis treatment? - Chagas Triatomine African Trypanosomiasis treatment? - Trypan Brunei

Answer 31

Tx Chagas - Nitro + imidazole Tx African Trypan - Pentamidine

Question 32

Commonest cause of CHRONIC Traveler's diarrhea? Treatment for it?

Answer 32

Giardiasis lamblia Metronidazole

Question 33

Best test to differentiate PUO from factitious fever?

Answer 33

ESR

Question 34

How hiprex ( methenamine hippurate) works as UTI prophylaxis? Hiprex contraindicated in? Hiprex no use in what condition?

Answer 34

Need Acidic urine pH < 5.5 -it will dissolve to form ammonia and formaldehyde ( bactericidal) Contraindicated; - Hepatic dysfunction - it releases ammonia - renal dysfunction - Sulfonamides usage - it binds to formaldehyde becomes insoluble No use in; indwelling catheter - too much drainage - can't form formaldehyde Proteus infection - proteus alkaline the urine

Question 35

Listeria always resistant to what drug? | How it evade immune system?

Answer 35

Cephalosporins - hence use benzylpenicillin Hijack actin polymerisation propulsion - spread cell to cell without extracellular environment