Tropical Medicine: Brains Worms and TB Flashcards
What has improved life expectancy since 1900?
Toilets Synthetic fertilisers Blood transfusions Green revolution Vaccines
How much TB is from (1) primary infection or (2) latent reactivation?
50/50
What is MDR-TB?
o Three countries account for ~50% all MDR-TB:
India 24%
China 13%
Russia 10%
o 558,000 acquired Rifampicin-resistant TB
What is TB a disease of?
Poverty
What can reduce impact of TB?
- TB control programmes can avert deaths but have no effect on transmission/incidence rates
- Socioeconomic development can reduce transmission/incidence rates
- CRESIPT = Community Randomised Evaluation of a Socio-economic Intervention to Prevent TB
What are the risk factors for MDR-TB?
Prior TB therapy Recreational drug use Presence of cavities HIV History of imprisonment Low BMI/ poverty/ malnutrition
How do we improve diagnosis?
o Improve diagnostic capacity (infrastructure, training)
o Export patient materials to central facilities
o Improve transport
o Improve stability of biomaterials
How do we do rapid diagnosis of TB?
o DNA extraction from cultures and clinical specimens (sputum)
o PCR amplification
o Hybridisation with DNA probes on membranes
o Development, reading. and interpretation of results
What is the WHO recommendation for TB identification?
o For primary specimens and cultures -> LPA (Laryngopharyngeal Aspirate) for diagnosing XDR-TB
o Serology testing is useless -> WHO made a NEGATIVE recommendation to do serology testing
o Emphasis on oral regimens to treat MDR-TB
What is the most common cause of adult onset seizure?
Brain worms are the MOST COMMON cause of adult-onset seizures in the world
What is the CT scan findings of brain worms?
Midline is NOT shifted (suggests lesion present for long time)
It has a cystic membrane and a fluid-level
White = calcification (immune system cannot kill pathogens)
How many people in the world have latent TB?
25%
What is the lifecycle of taenia solium?
Tapeworms normally live in the intestines and are usually ASYMPTOMATIC and may last for many years
Tapeworms produce eggs which are excreted in human faeces and then ingested by pigs
The pigs then develop porcine cysticercosis
In human cysticercosis, humans eat EGGS (not the cysts), and the eggs burrow into tissues (mistaken for pigs
Why do pigs eat human faeces?
o Pigs seek out human faeces because they have a problem with iron deficiency and human faeces are rich in iron
o Pigs with cysticercosis can be identified by palpating their tongue (it will be lumpy because of the cysts)
o Fish and beef tapeworms do NOT cause cysts in humans
o Pork tapeworms can cause a cystic infection in humans because pigs are immunologically similar to humans
What kills pork tapeworm?
Cooking
Freezing
