Lyme's Disease Flashcards
What is Lyme disease?
It is defined as a multisystem disease caused by the spirochaete, Borrelia Burgdorferi
How is Lyme disease transmitted?
Ticks
When does the localised stage of Lyme disease occur?
It occurs between 3 – 30 days following a tick bite
What are the five clincial features of Lyme disease at the localised stage?
Erythema Migrans
Fatigue
Fever
Headache
Arthralgia
What is erythema migrans?
It is defined as a bulls eye rash, which develops at the site of the tick bite
When does erythema migrans present in Lyme disease?
1 - 4 weeks > tick bite
What are the three charcteristic features of erythema migrans?
Painless
> 5cm in diameter
Slowly increases in size
In cases where individuals present with erythema migrans, what is the most appropriate next step?
Antibiotics
This is due to the fact that in these cases diagnosis is clincial
When does disseminated stage of Lyme disease occur?
It occurs after 30 days of a tick bite
What two organ systems are most commonly affected by Lyme disease in the disseminated stage?
Cardiology
Neurology
What are the six clincial features of Lyme disease in the disseminated stage?
Heart Block
Pericarditis
Myocarditis
Facial Nerve Palsy
Radicular Pain
Meningitis
What are the two investigations used to diagnose Lyme disease?
Enzyme-Linked Immunosorbent Assay (ELISA)
Immunoblot Test
What is the first line investigation used to diagnose Lyme disease?
Enzyme-Linked Immunosorbent Assay (ELISA)
What is ELISA?
It is used to detect the presence of antibodies within blood
What is the next appropriate step following a positive ELISA result?
It is recommended that an immunoblot test is conducted
What is the next appropriate step following a negative ELISA result, however Lyme disease is still suspected in individuals tested within four weeks of clinical feature onset?
It is recommended to repeat the test 4 – 6 weeks after the first ELISA test
What is the next appropriate step following a negative ELISA result, however Lyme disease is still suspected in individuals tested after twelve weeks of clinical feature onset?
It is recommended to conduct an immunoblot test
What is the second line investigation used to diagnose Lyme disease?
Immunoblot Test
What is the immunoblot test?
It is used to detect specific antigens recognised by polyclonal or monoclonal antibodies
How do we conduct tick removal?
It is conducted with fine-tipped tweezers, in which the head of the tick is grasped as close to the skin as possible and pulled firmly upwards
The area should then be washed following removal
What is the management option for Lyme disease?
Antibiotics
What is the first line antibiotic used in cases where individuals present at the localised stage of Lyme disease? At what dose?
Oral Doxycycline
100mg for 14-21 days
What is the second line antibiotic used in cases where individuals present at the localised stage of Lyme disease?
Amoxicillin
What is the first line antibiotic used in cases where individuals present at the disseminated stage of Lyme disease? At what dose?
IV Ceftriaxone
14 - 30 days
Are prophylactic antibodies reocmmended following a tick bite?
No
What is a common complication following antibiotic administration for Lyme disease?
Jarisch Herxheimer reaction
When does Jarisch Herxheimer reaction present following antibitoic adminsitration?
It tends to occur after administration of the first antibiotic dose
What are three Jarish Herxheimer reaction clincial features?
Fever
Rash
Tachycardia
