Tuberculosis and Malaria Flashcards
What is tuberculosis?
curable infectious disease caused by bacteria of the Mycobacterium tuberculosis complex
What are the treatment phases for TB?
initiation phase: RIPE - 2 mth
- rifampicin, isoniazid + pyridoxine, pyrazinamide and ethambutol
continuation: RI - 4 mth
- rifampicin and isoniazid + pyridoxine
What is treatment for latent TB?
either
- 3 months of isoniazid + pyridoxine and rifampicin
or
- 6 months of isoniazid + pyridoxine
What should be done if drug-induced hepatotoxic treatment interruption occurs for TB?
once LFTs have returned to normal ranges
- should be sequentially re-introduced at previous full doses over a period of no more than 10 days.
Start with ethambutol hydrochloride and either
- isoniazid + pyridoxine
or
- rifampicin
When is rifampicin contraindicated? What is the caution associated?
contraindication
- jaundice
caution
- discolours bodily fluids and soft contact lenses: RED
What is the contraindication for ethambutol?
optic neuritis (inflammation of optic nerve)
poor vision
causes ocular toxicity
- especially in excessive dosage or renal impairment
What is the contraindication for pyrazinamide?
acute attacks of gout
What must isoniazid be given with and why?
pyridoxine (vitamin B6)
- isoniazid causes peripheral neuropathy
more likely with diabetes, alcohol dependence, chronic renal failure, pregnancy, malnutrition and HIV infection.
Which TB medications are associated with hepatotoxicity?
rifampicin - monitor LFTs
isoniazid - monitor LFTs
pyrazinamide - avoid for 6 months post severe impairment
What TB medications affect CYP enzymes?
rifampicin - inducer
isoniazid - inhibitor
How does rifampicin affect contraception?
CYP inducer
- effectiveness of hormonal contraceptives is reduced and alternative family planning advice should be offered.
What are the monitoring requirements for TB medications?
rifampicin - renal function, LFTs and blood counts
isoniazid - renal function and LFTs
pyrazinamide - renal function and LFTs
ethambutol - renal function and visual acuity
What is a significant interaction for isoniazid?
tyramine-rich foods: mature cheeses, salami, Bovril® or any similar meat or yeast extract or fermented soya bean extract, and some beers, lagers or wines)
histamine-rich foods: very mature cheese or fish from the scromboid family (e.g. tuna, mackerel, salmon)
tachycardia, palpitation, hypotension, flushing, headache, dizziness, and sweating can occur
How can you protect yourself against malaria?
mosquito bed nets with a pyrethroid insecticide - permethrin
plug-in vaporised insecticides
wearing long sleeved clothing, long trousers and socks
insecte repeint - DEET
- 1st line 50% DEET - for >2 months
What is prophylaxis for malaria?
atovaquone + proguanil - 1-2 days BEFORE and 1 week AFTER
doxycycline - 1-2 days BEFORE and 4 weeks AFTER
chloroquine - 1 week BEFORE and 4 weeks after
mefloquine - 2-3 weeks BEFORE and 4 weeks AFTER
Which anti-malarials cannot be used in epilepsy?
chloroquine and mefloquine
- lower seizure threshold, exacerbate seizures
contraindication
Which anti-malarials can be used in pregnancy?
mefloquine
- caution in 1st trimester
- yes in 2nd and 3rd trimester
atovaquone + proguanil
- if others are not suitable then yes in 2nd and 3rd trimester
- must given folic acid alongside it: 5mg OD
How should people taking anti-coagulant be treated with anti-malarials?
start 2–3 weeks before departure and the INR should be stable before departure
- monitor BEFORE, 7 days AFTER and after COMPLETING the course
What is treatment for malaria?
Falciparum malaria
- artemisinin combination therapy: artemether with lumefantrine
- quinine
- atovaquone + proguanil
Non-falciparum malaria
- artemisinin combination therapy: artemether with lumefantrine
- chloroquine
What medications should chloroquine NOT be taken with?
MHRA
macrolides
- increased risk of cardiovascular events
What is the MHRA warning for chloroquine?
avoid taking with macrolides
- increased risk of cardiovascular events
- azithromycin, clarithromycin
risk of psychiatric reactions
What is the time frame for getting ill with malaria?
immediate visit to doctor if ill within 1 year and especially within 3 months of return.
What is a red flag for mefloquine?
associated with neuropsychiatric reactions
- abnormal dreams, insomnia, anxiety, depression, psychosis, suicidal ideation, suicide
Is contraception needed during mefloquine use?
yes
- teratogenic
- needs contraception during prophylaxis and for 3 months after stopping
