Febrile returned traveller Flashcards Preview

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Flashcards in Febrile returned traveller Deck (11)
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1
Q

History key points of travelled patient

A

Where have you been and what did you do?- Organism exposure

When were you there and when did you start to get sick- timeline fit with incubation

2
Q

Infections with clinical features and incubation:

Influenza; TB; salmonella typhi and enteritidis; campylobacter jejuni; hep A; malaria; dengue;HIV; syphilis

A
  • resp, few days; air
  • resp, many months; air
  • non specific and diarrhoea, days; water + food
  • diarrhoea, days; water + food
  • jaundice, weeks; water + food
  • non specific, weeks; vectors
  • muscle aches, days; vectors (aedes mosquito)
  • non specific, weeks to months; people
  • variable, weeks to months; people
3
Q

Malaria causing organisms

A

Protozoa, inside anophles mosquito vector

Common: plasmodium falciparum (potentially fatal) and vivax (pretty benign)
Rare: Ovale and malariae

4
Q

Places with anophles mosquitos and thus higher risk of acquiring malaria

A

PNG, Solomons an Vanuatu

None in New caledonia, Fiji, Samoa, Tonga etc

5
Q

Plasmodium pathogenesis

  • Infected ____ mosquito feeds on blood, and injects ___, containing _____ (infects new host)
  • ______ invade ____ cells and replicate (10 days)
  • ______ (from liver cell replication) are released from liver and invade _____
  • Replicate in ______ and rupture them, ___, rigors, sweats
  • Reinfects blood cells
  • Some _____ mature into male or/and? female gametocytes which are source of sexual replication in mosquito salivary gland

body can keep under control and have low levels of circulating protozoa

A
  • Infected female mosquito feeds on blood, and injects saliva, containing sporozoites (infects new host)
  • Sporozoites invade liver cells and replicate (10 days)
  • Merozoites (from liver cell replication) are released from liver and invade RBC’s
  • Replicate in erythrocytes and rupture them causes, fever, rigors, sweats
  • Reinfects blood cells
  • Some merozoites mature into male or/and? female gametocytes which are source of sexual replication in mosquito salivary gland

body can keep under control and have low levels of circulating protozoa

6
Q

Differences between plasmodium falciparum and vivax

A

Falciparum: able to infect any RBC; changes membrane proteins, causing capillary adherence, blocking blood flow; sequestration in capillaries in brain and kidneys; death from coma and renal failure
Vivax: Young RBC’s; no RBC sequestration; has hypnozoites that remain in liver and cause relapse

7
Q

Malaria treatment

A

P. falciparum: Qunine and doxycycline or artemether+ lumefantrine to kill merozoites

P. vivax: chloroquine, primaquine to kill dormant hypnozoites

8
Q

Malaria prevention

A

Avoid malarious areas; mosquito control; bed nets, long sleeves etc; insect repellant; doxycycline, mefloquine

9
Q

Dengue fever: features; incubation; symptoms

A

RNA virus, aedes mozzy, multiplies in macrophages
2-7 days
Breakbone fever: muscle aches, mylgia, bone pain
1 week to recover

10
Q

Salmonellae

A

Enteritidis: from animals and birds, infects mucosa in colon= colitis. gastroenteritis

Typhi: from people and infects peyers patches (terminal ileum)- causing bactaraemia and septicaemia. Typhoid fever

11
Q

Typhoid fever presentation and treatment

A

fever, rigors, sweats, cough, headache, confusion, ot usually diarrhoea but constipated
Risk of peritonitis or ileal vessel erosion= bleeding
Long term bladder colonisation

Treat with ceftriaxone IV or ciprofloxacin O.