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Flashcards in Travel medicine Deck (57)
1

Appearance of red cells in P falciparum and P vivax?

Falciparum: normal size cells, loads of ring forms, crescent shaped gametocytes
Vivax: large RBC, fewer infected, fine, eosinophilic dots

Thick film is to concentrate the parasites
Thin film is for species identification

2

In cerebral malaria, what are the LP and imaging findings?

Normal opening pressure
No evidence cerebral oedema on imaging usually

3

Lab findings in malaria?

Anaemia
NO eosinophilia
If anaemia ALWAYS have thrombocytopaenia
Acidosis
Hypoglycaemia

4

What malaria prophylaxis in T2 and T2 pregnancy?

mefloquine

5

What should you use as malaria resistance when not sure about resistance patterns?

mefloquine
Doxycycline
Primaquine
Atovaquone-proguanil

6

What do you have to give in P Vivax or P Ovale to prevent relapse?

Chloroquine should always be followed by course of Primaquine (check G6PD def first) to eradicate hypnozoites
A 14 day course can cause haemolytic anaemia

Dominant liver stages

7

Treatment for bad malaria?
What elements of supportive care?

IV Artesunate- assume chloroquine resistant P falciparum
Ensure no hypo
Transfuse if haematocrit drops below 20%
Treat seizures with benzos
When can take tabs should have full course of artemisinin combination
-artemether + lumefantrine
-atovaquone + proguanil
-quinine sulphate + doxy

If non life threatening antemether-lumefantrine ok

8

At what point in the life cycle does fever happen in malaria?

Schizont rupture (RBC)

9

P falciparum incubation period

1-4 weeks
So fever under 1 week after ariving in endemic area unlikely malaria
Vivax can come on weeks to months post return

10

What is the use of the immunochromatographic test in malaria? ICT

Rapid test not dependent on expertise for P falciparum and vivax
Good negative predictive value
Quite sensitive
Stays positive post treatment

11

What is the mutation that gives resistance to mefloquine and chloroquine?

Pfmdr1

12

SE asia there is lots of resistance to what malaria agent?

Mefloquine- so need to give doxy or atovaquone - proguanil

13

Contraindications to mefloquine use?

Psychiatric disorders
Epilepsy
Cardiac conduction defects

14

How long do you have to continue agents after coming back (prophylaxis?)
-Atovaquone proguanil
-Doxy
-Mefloquine

AP: 1 day before 7 days post return
D:1 day before 4 weeks post
M: 2 weeks before travel 4 weeks post

15

Typhoid fever classic presentation

Fever, abdominal pain and CONSTIPATION
(not diarrhoea)
Hepatosplenomegaly
Neuropsych
RELATIVE BRADYCARDIA
Rose spots on trunk

16

Febrile and brady in the returned traveller, think...

Typhoid!!

17

Complications of typhoid- what time frame and when are they?

3rd or 4th week

Intestinal perforation
Bone and joint
Endocarditis and pericarditis
Splenic or liver abscess
Endovascular infection- especially old aneurysms, plaques, grafts

18

Diagnosis for Typhoid?

Blood culture
Stool culture
bone marrow!
See leukopaenie and anaemia, low eosinophils, low plt
Abnormal LFTs
Mild CK rise

19

Treatment for typhoid?

NOT cipro- lots of resistance now
Ceftriaxone
Azith if there is drug resistance
Dex if severe and neuropsych
take ages 5-7 days to stop fever

20

What is the risk of chronic typhoid carriage?

LIKE TYPHOID MARY!!!!
Higher frequency if biliary abnormality or concurrent bladder infection with Schistosoma
Gallbladder cancer!

21

Incubation period of S Typhi?

Usually about 2 weeks, but can be longer weeks to a month or two

22

Classic dengue presentation?

Fever
Headache
RETROORBITAL PAIN
MSK pain "breakbone fever"
Rash- macular rash with "islands of white"
palpable liver

WITHIN 14 DAYS of even brief trip to tropics or subtropics
Incubation 3-7 days

remember that defervesce for 1-2 days after the vomiting and diarrhoea and lymphadenopathy stage. Then get more fever, morbilliform rash, skin peels off, possible dengue shock. DONT SEND TOO EARLY HOME

23

How do you make a dengue diagnosis?

Often of exclusion, hard to do
Flavivirus PCR or ELISA to NS1 (whilst febrile)
High IgM with paired samples
Increase in IgG by 4 fold over 2 weeks if already present at diagnosis
See leukopaenia, thrombocytopaenia, neutropaenia
Hypoalbuminaemia and proteinuria
Arbovirus IgM specific
If plt under 100 or transaminases more than 3-5-->warning severe

24

What is the feared complication of dengue?

Dengue haemorrhagic fever
-haemorrhage spontaneously or with tournequet
-plt unde 100
-fever 2-7 days
-evidence of PLASMA LEAK based on pleural effusions and changes in haematocrit

25

What is the treatment for dengue

Supportive
Fluids
Avoid vectors

26

What are the range of presentations of entamoeba histolytica?

Asymptomatic infection to acute dysentery to toxic megacolon and perforation
Extraintestinal disease: liver, lung, brain abscess

27

Diagnosis of entamoeba histolytica?

3 fresh specimens stool for cysts and trophozoites
99% with liver abscess with have positive serology

28

Treatment for entamoeba histolytica?

metronidazole
+
paromomycin or diloxanide furoate (prevents continued luminal infection)

29

What is the management of acute hep A?

Supportive
Isolate
Give IMMUNE GLOBULIN
Vaccinate those at risk

30

Cruise ship gastro, think what?

Norwalk virus

31

What's the deal with campylobacter jejuni from Thailand?

Lots of cipro resistance

32

When do you need to give meningococcal prophylaxis?

Direct contact with respiratory secretions.
If sitting beside infected patient for longer than 8 hours.

33

What viral family is Ebola from?

Filovirus
There are 5 subspecies- the recent one was Zaire

34

Ebola mortality

70%

35

Ebola incubation period

11 days
Present with fever, weakness, diarrhoea
Join onto cells via GP1 and 2

36

Ebola diagnostic test

Ebola PCR positive 1 day before symptoms

37

Ebola treatment

Fluid and electrolytes
Nutritional support
Watch for bacterial superinfections

38

Schistosomiasis treatment

Single dose praziquantel

39

Schistosomiasis presentation

Itchy rash within a few days of swimming in fresh water

4-8 weeks post infection have acute self limiting febrile illness and marked eosinophilia

Months to years later can get diarrhoea, abdo pain, or haematuria or painful ejaculation as there is an inflammatory response in the bowel or bladder

Chronic infection can give you colitis, portal hypertension (most common cause of varices), chronic liver disease, SCC bladder, urolithiasis

Eosinophils up in half.
Serology is sensitive but takes months to go up
Urine micro from 10 am to 2pm
Semen analysis, stool micro, rectal biopsy

40

Ascariasis - what does it look like?

GROSS MASSIVE WORMS IN THE GUT!!!

Most common human helminthic infection.
usually asymptomatic

Africa, SE asia

Worms gut-->portal vein-->lungs-->cough and swallow

Diagnosed on stool microscopy

Tx: mebendazole

41

Rabies: what is the clinical picture?

Fever headache malaise prodrome
Encephalitis with hydrophobia
Delirium and agitation
Autonomic dysfunction
Ascending flaccid paralysis

42

How is Chikungunya spread?

Alphavirus- aedes aegypti mosquito that also spread dengue

43

What does Chikungunya look like clinically?

In someone back from India, Malaysia, Caribbean, indian ocean islands and after 1-14 days develop fevers, arthralgias, rash, myalgia
Pointer is often painful JOINTS ++++-->chronic arthritis in 5-60%

44

How do you diagnose Chikungunya?

Aplhavirus PCR
Serology

45

When do you have higher risk of death with malaria?

Parasitaemia over 5%
Pregnancy
No prophylaxis
Splenectomy
Extremes of age
Delayed time to treatment

46

Giardia- what are the stools like?

Slimy not explosive

Treatment is metronidazole or tinidazole

47

Fever plus rash in the returned traveller?

Dengue
Chikungunya
Riclettsia
Meningococcus, gonococcus, syphilis
HIV, EBV, CMV
Malaria less likely

48

Fever and lymphadenopathy?

Rickettsia
TB
Syphilis
Filariasis
Tularaemia

49

Name two helminths

Strongyloides
Schistosomiasis

50

Name five protozoa

Giardia
Malaria
Entamoeba
Cryptosporidium
Toxoplasma
Leishmaniasis

51

What do you think if severe malaria and haemodynamically compromised?

Suspect sepsis overlying
Malaria alone does not often do this

52

WHat does japanese enceph look like and how to diagnose?

Diagnose with CSF IgE- PCR useless

dystonic features, parkinsons movements

53

max number of times you can get dengue?

4- each time only temporary resistance against the other three strains but lifelong against the one you have had

54

Most specific deficit in early dengue in lab?

leukopaenia (not low plt)

55

LFTs in dengue?

AST>ALT

56

Dengue inc period

4-7 days

57

Fever and rash and African Safari

Rickettsial