Travel medicine Flashcards
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
In cerebral malaria, what are the LP and imaging findings?
Normal opening pressure
No evidence cerebral oedema on imaging usually
Lab findings in malaria?
Anaemia NO eosinophilia If anaemia ALWAYS have thrombocytopaenia Acidosis Hypoglycaemia
What malaria prophylaxis in T2 and T2 pregnancy?
mefloquine
What should you use as malaria resistance when not sure about resistance patterns?
mefloquine
Doxycycline
Primaquine
Atovaquone-proguanil
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
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
At what point in the life cycle does fever happen in malaria?
Schizont rupture (RBC)
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
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
What is the mutation that gives resistance to mefloquine and chloroquine?
Pfmdr1
SE asia there is lots of resistance to what malaria agent?
Mefloquine- so need to give doxy or atovaquone - proguanil
Contraindications to mefloquine use?
Psychiatric disorders
Epilepsy
Cardiac conduction defects
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
Typhoid fever classic presentation
Fever, abdominal pain and CONSTIPATION (not diarrhoea) Hepatosplenomegaly Neuropsych RELATIVE BRADYCARDIA Rose spots on trunk
Febrile and brady in the returned traveller, think…
Typhoid!!
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
Diagnosis for Typhoid?
Blood culture Stool culture bone marrow! See leukopaenie and anaemia, low eosinophils, low plt Abnormal LFTs Mild CK rise
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
What is the risk of chronic typhoid carriage?
LIKE TYPHOID MARY!!!!
Higher frequency if biliary abnormality or concurrent bladder infection with Schistosoma
Gallbladder cancer!
Incubation period of S Typhi?
Usually about 2 weeks, but can be longer weeks to a month or two
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