Infection, Tetracyclines

Question 1

The tetracyclines are broad-spectrum antibiotics whose value has decreased owing to increasing bacterial resistance. They remain, however, the treatment of choice for infections caused by what?

Answer 1

1. Chlamydia (trachoma, psittacosis, salpingitis, urethritis, and lymphogranuloma venereum)
2. Rickettsia (incuding Q-fever)
3. Brucella (doxycycline with either streptomycin or rifampicin)
4. Spirochaete, borrelia burgdorferi.

Question 2

Tetracyclines are also used in respiratory and genital mycoplasma infections, in acne, in destructive (refractory) periodontal disease and in exacerbations of chronic bronchitis. Why are the used in exacerbations of chronic bronchitis?

Answer 2

They have activity against haemophilus influenzae.

Question 3

Tetracyclines also have a role in the management of what resistant infection?

Answer 3

MRSA

Question 4

Which tetracycline has the broadest spectrum?

Answer 4

Minocycline: it is active against Neisseria meningitidis and has been used for meningoccocal prophylaxis but is no longer recommended because of side-effects including dizziness and vertigo.

Question 5

Compared to other tetracyclines, minocycline has a greater risk of what syndrome?

Answer 5

Lupus-erythematous-like syndrome.

Question 6

Minocycline can sometimes cause what irrerversible side effect?

Answer 6

Irrerversible pigmentation.