Mi - Imported Fevers Flashcards
components of a good travel history (6)
where did you go - inc stop overs / rural vs urban / exact location
when did you go - inc sx onset
why did you go - holiday / VFR (visiting friends and relatives)
what did you do - activities / interactions
pre travel vaccines / malaria prophylaxis
what is the incubation period of malaria
months
what is the incubation period of viral haemorrhage fever
3 to 21 days
what can exposure to tic bite put you at risk of
CCHF (VHF)
Lyme disease
what can exposure to animal bites put you at risk of
CCHF (VHF)
MERS
rabies
what can being on a cruise put you at risk of
Legionnaires (zircon)
norovirus
what can freshwater activities put you at risk of
schistosomiasis
leptospirosis
what can sexual contact put you at risk of
HIV
hep
PID
what tropical diseases can you get from food /water
hep E
cholera
what travel activity type puts you at greater risk of tropical diseases and why
visiting friends and relatives (VFR)
less likely to adhere to prophylaxis and more likely to do weird activities / eat weird foods
54M fever, headache, rigors. UK national but visited Lagos 1 week ago VFR. Already had amoxicillin from GP but not helped. Dx?
malaria
what can cerebral malaria present with
confusion
Ix for malaria
FBC
CRP
U&Es
HIV
blood film - thick and thin
malaria rapid diagnostic test
blood parasitaemia
what does malaria look like on blood film
‘headphones’ - 2 dots on one cell
what Ix can show if malaria is severe or not
parasitaemia in blood
who carries the biggest mortality burden of malaria
<5 y/o African children
Africa has ___% of all malaria cases
95%
how many strains of malaria are there
5
what strain of malaria are 75% of cases
plasmodium falciparum
where does p.falciparim invade in the body
RBCs
what strain are 20% of malaria cases
p.vivax
main stages of malaria lifecycle
mosquito stage
human stage - liver then RBC stage
in which stage is asexual reproduction of malaria
RBC stage
what features are part of a malaria risk assessment
geography
altitude - lower risk at high altitude
preg
urban vs rural - inc accommodation
how can malaria be prevented
repellents
nets
prophylaxis
name 2 drugs that can be used as malaria prophylaxis
malarone
mefloquine
when do people present post bite with malaria
10 to 15 days usually but can be months
what stage does vivax have that means people can present at any time
hypnozoite stage
what type of fevers do you usually get in malaria
cyclical or spiking
what is the malaria paroxysm
chills, high fevers and sweats
what 10 features indicate malaria is severe
high parasitaemia
change in conciousness
respiratory distress
circulatory collapse
metabolic acidosis
renal or hepatic failure
coagulopathy / DIC
severe anaemia / intravascular haemolysis
hypoglycaemia
schizont on film
what is a schizont
multiple malaria dots on 1 cyst
what is classified as high parasitaemia in malaria
> 2% or >5% in non imm
what is the purpose of the thick vs thin film in malaria
thick = see presence of any parasites
thin = see the species of malaria present
what are the rapid malaria detection kits
lateral flow like test that you blob blood on and see if 1 or 2 lines become present
name 2 brands of rapid malaria detection kits
Paracheck-Pf
OptiMAL-IT
Tx of non falciparum malaria
3d oral tabs chloroquine and 14d primaquine
what do you need to check before starting primaquine and why
G6PD
- if deficient, get severe haemolysis
Tx for mild falciparum malaria
ACT / macarons
Tx for severe falciparum malaria
IV artesanate
3 features that make malaria mild
not vomitting
parasitaemia <2%
ambulatory
what advice is given to patients regarding taking ACT
eat with a high fat meal to improve absorption
3 additional Mx components of severe malaria
correct any hypoglycaemia
cautious fluids
daily parasitaemia then PO follow on with ACT
why should fluids only be given cautiously in severe malaria
avoid pulmonary oedema
side effects of artesemate
delayed haaemolysis
side effects of quinine
cinchonism
arrhythmias
hyperinsulinaemia
what is cinchonism
tinnitus and dizziness
- specific in quinine OD
53M from Thailand, had visited Thailand 5/7 before Sx
PC: fever, headache, arthralgia, rash
No malaria prophylaxis
O/E: conjunctival injection, sunburn rash which can leave a palm print on skin
Dx?
Dengue fever
what transmits dengue
aedes aegypti mosquito
how many serotypes of dengue are there
4
what type of virus is dengue
flavivirus
if you recover from 1 type of dengue, what is your prognosis RE reinfections
lifelong immunity from that type
can get cross reactivity with other types
where does dengue replicate and where does it migrate to
replicates in midgut
migrates to salivary glands
2 risk factors for Dengue in terms of travel
day time > night time
urban > rural
recovery time from dengue usually
1-2 weeks
incubation period of dengue
4-7 days
5 classic Sx of dengue
high fever
retrorbital headache
myalgia / arthralgia
sunburn rash
nausea and vomitting
what complication can occur once the fever has subsided in dengue
haemorrhage sx eg shock / haemetemesis / organ impairment
when should serology be done for dengue
after 5-7 days to get IgG/M
33F
PC: fever, constipation, dry cough, abdominal pain, vacant expression
Been to India 2/52 ago.
O/E: high temp, normal HR, normal platelets, raised CRP
Clear CXR, clear ECG
Spiking fevers
Culture shows gram - rods on day 3, which are flagellated.
Dx?
salmonella typhi
33F
PC: fever, constipation, dry cough, abdominal pain, vacant expression
Been to India 2/52 ago.
O/E: high temp, normal HR, normal platelets, raised CRP
Clear CXR, clear ECG
Spiking fevers
Culture shows gram - rods on day 3, which are flagellated.
relevance of the normal HR?
would expect HR to be high if spiking a fever so this is worrying
33F
PC: fever, constipation, dry cough, abdominal pain, vacant expression
Been to India 2/52 ago.
O/E: high temp, normal HR, normal platelets, raised CRP
Clear CXR, clear ECG
Spiking fevers
Culture shows gram - rods on day 3, which are flagellated.
what can the spiking fevers pattern be described as in salmonella typhi?
‘Himalayan peak temperatures’
33F
PC: fever, constipation, dry cough, abdominal pain, vacant expression
Been to India 2/52 ago.
O/E: high temp, normal HR, normal platelets, raised CRP
Clear CXR, clear ECG
Spiking fevers
Culture shows gram - rods on day 3, which are flagellated.
what is the significance of the normal platelets?
malaria and dengue cause a low platelet count
33F
PC: fever, constipation, dry cough, abdominal pain, vacant expression
Been to India 2/52 ago.
O/E: high temp, normal HR, normal platelets, raised CRP
Clear CXR, clear ECG
Spiking fevers
Culture shows gram - rods on day 3, which are flagellated.
what is the relevance of the vacant expression?
classic with salmonella typhi
what are some salmonella typhi resistant to
cipro
how is salmonella typhi diagnosed
blood / BM / stool culture
how is salmonella typhi transmitted
faeco-oral route
is there an animal reservoir for salmonella typhi
NO
how is salmonella typhi prevented
hand hygiene
vaccine
salmonella typhi is ___x more likely in ____
10x in indian subcontinent
features of salmonella typhi fever
gradual, high, prolonged fever
other sx of salmonella typhi
rose spots (rare)
headache
constipation
dry cough
3 stages of salmonella typhi sx
1 = fever with low / inappropriately normal HR
2 = extreme fatigue, delirium
3 = intestinal haemorrhage, encephalitis, resp complications
Mx of salmonella typhi
oral rehydration solution
IV ceftriaxone
follow on with oral azithromycin
what is the pre ABx fatality of salmonella typhi
10-20%
