Infectious diseases

Question 1

Testing for TB

Answer 1

FBC, U&E, ESR CRP, interferon gamma test
Sputum AFB/Bronchoscopy and lavage
CXR
Prior to treatment: RFT, LFT, visual acuity

Question 2

Managing TB

Answer 2

• screen family members and close contacts
• report to health authorities
• 2 months 4 drugs initially, then 4 months 2 drugs
• isoniazid, rifampicin, pyrazinamide, ethambutol
• DOTS treatment, have to be compliant
• regular follow-up and repeat investigations at 2 and 6 months

Question 3

Diagnosing EBV

Answer 3

FBC, PBF

Monospot for heterophil antibody, EBV-specific antibody, VCA antibody

Question 4

Management for EBV

Answer 4

Supportive, rest during acute stage
NSAIDS/PCM
Gargle soluble aspirin/30% glucose
Adequate hydration
Advise AGAINST alcohol, fatty food, contact sports (splenic rupture)
Steroids only if neuro involvement, thrombocytopenia, threatened airway obstruction

Question 5

Triad for malaria and other features

Answer 5

Fever + chills + headache

Rigor, sweating, myalgia, anemia, jaundice, hepatosplenomegaly, atypical (diarrhoea, abd pain, cough)

Question 6

Malaria prevention (8 steps)

Answer 6

• keep away from rural areas
• avoid outdoor activities between dusk and dark
• sleep in AC/properly screened rooms
• use mosquito coils at night
• insect repellent on body
• mosquito nets with permethrin
• light-coloured clothing, long sleeves and trouser
• avoid perfume, cologne, after-shave

Question 7

Malaria drug prophylaxis dose, duration, SE

Answer 7

Doxycycline 100mg OD for 1-2 days before, then during and for 4 weeks after.

Photosensitivity reactions

Question 8

Investigations for malaria

Answer 8

PBF Thick and thin

FBC - anemia, leukocytosis, thrombocytopenia

Question 9

Treatment of malaria

Answer 9

P falciparum: Quinine-based with quinine sulfate + doxycycline/clindamycin. Alternative is artemether-lumefantrine

P vivax and P ovale: chloroquine + primaquine

P malariae: chloroquine

Question 10

Malaria paroxysm and when it happens

Answer 10

at 8-12 hours: suddenly feel very cold > mild shivering > violent shaking. after that hot flush with throbbing headache, palpitations, tachypnea, postural syncope and vomiting.

Question 11

Tests for Hepatitis A

Answer 11

LFT, HAV IgG and IgM.

Ultrasound to exclude bile duct obstruction

Question 12

Management of Hepatitis A

Answer 12

Rest, fat-free diet
Avoid alcohol, smoking, hepatotoxic drugs
No sex, no IV drugs, wash hands after toilet and disinfect, don’t handle others’ food, don’t share cutlery, don’t use towels to dry.

Question 13

Prevention of Hep A

Answer 13

Hygiene

Immuneglobulin for close contacts and travelers to endemic areas for up to 3 months

Question 14

Test for Hepatitis B

Answer 14

If HbsAg positive: do full viral profile and it signifies current infection/chronic infection (carrier if >6 months)
If HbeAg positive: active replication
If anti-Hbe: inactive virus and not infective
If HBV DNA high; active replication
If anti-HbC positive: previous/ongoing infection

Question 15

Management and monitoring of Hep B

Answer 15

Avoid alcohol, avoid certain drugs till recovered like sedatives, NSAIDS, OCP
Hygiene like Hep A
Treat chronic Hep B with interferon and antiviral
Monitor LFT, HBeAg and HBV DNA, alpha-fetoprotein 6-12 monthly

Question 16

Diagnosis of Hep C

Answer 16

By serology
HCV Ab: exposure
HCV RNA: chronic viraemia. once negative infection cleared
Must check CD4/HCV viral load and ALT (if high need referral)

If PCR positive, significant viral load, ALT high > perform HCV genotype

Question 17

Management of Hepatitis C

Answer 17

Direct-acting antiviral + interferon

Pretreatment assessment: Confirm diagnosis, test for genotype and viral load, document travel history, evaluate comorbids and liver status, discuss contraception and pregnancy, select treatment regimen and review potential drug interaction

Question 18

Hepatitis C cure confirmed when

Answer 18

Undetectable plasma HCV RNA at least 12 months post management

Question 19

Tests for HIV

Answer 19

HIV infection: ELISA/HIV rapid test, if positive Western blot to confirm
immune function: CD4 lymphocyte count. <500 is defective, <200 is severely immunodeficient
Plasma HIV RNA
Test for opportunistic infection
Routine test: FBC UEC FBG lipid eGFR

Question 20

Management of HIV

Answer 20

Preferred regimen: 2NTI + NNRI/PI

Question 21

What vaccine required for Africa and South America

Answer 21

Yellow fever

Question 22

What vaccine needed for India

Answer 22

Typhoid

Question 23

What vaccine needed for Saudi Arabia

Answer 23

Meningococcal

Question 24

Influenza management

Answer 24

Rest till fever subsides
analgesia
High fluid intake
Antivirals if elderly, pregnant, chronic disease, obese
- Oseltamivir 75mg Po BD for 5 days
- Zanamivir inhaled 10mg bd 5 days if oseltamivir resistant, poor response, poor GI absorption

Question 25

Complications of influenza

Answer 25

Pneumonia, tracheitis, bronchitis, bronchiolitis, toxic cardiomyopathy with SUDEP, encephalomyelitis, otitis media, Reye’s syndrome, depression

Question 26

Tests for influenza

Answer 26

Nasal/throat swab for viral PCR, viral antigen/detection or culture