Lincosamides

Question 1

Lincosamides

Answer 1

Clindamycin

A mix of Vanco and Metronid
Has attributes of each but not quite as good as either alone

An alternative when Gram+ activity needed (like a beta lactam allergy); but has more variable activity than Vanco against MRSA and S. pyogenes

Has activity against anaerobes; higher level of resistance among Gram- anaerobes (like B. fragilis) than with Metronid

Has tendency to cause GI toxicity

Best used empirically for nonsevere infections of skin and oral cavity; or definitive therapy when susceptibility known

Question 2

Lincosamides MOA

Answer 2

Binds at site on 50S ribosome right next to where macrolides bind and acts similarity in preventing protein synthesis by preventing the ribosome from moving on to adding another amino acid in the protein chain

Question 3

Lincosamides Spectrum

Answer 3

Good
Many Gram+ anaerobes
Plasmodium species (malaria)
S. pyogenes

Moderate
S. aureus (including many MRSA)
Gram- anaerobes 
Chlamydia trachomatis 
P. jirovecii 
Actinomyces
Toxoplasma

Poor
Enterococci

C. difficile
Gram- aerobes

Question 4

Lincosamides Adverse Effects

Answer 4

GI
Diarrhea one of the most common adverse effects
1. Relatively benign self limited diarrhea
2. Can result in more severe diarrhea from superinfection with C. diff
C. diff associated diarrhea and colitis can occur during or after Clinda therapy and can be life threatening
Patients with diarrhea need evaluation for C. diff if
1. Severe diarrhea
2. Associated with fever
3. Persists after Clinda therapy

Dermatologic
Rash may occur (SJS very rare)

Question 5

Lincosamides Important Facts

Answer 5

Reasonable alternative for treatment of staph infections
Be careful interpreting antibiotic susceptibility of isolates
Significant proportion of organisms that are reported Clinda-susceptible but Eryth-resistant may harbor a gene for resistance that may lead to high level clindamycin resistance during therapy (screen these organisms with a D-test before using Clinda); if D-test is possible, don’t use it (inducible Clinda resistance is present)

Useful in treatment of necrotizing fasciitis and other toxin mediated diseases (because of its inhibition of protein synthesis and activity against organisms in stationary-phase growth)
When treating these infections with beta lactams, consider adding Clinda

Nearly 100% orally bioavailable
Oral doses generally lower than IV to improve GI tolerance

For CA-MRSA, more strains are susceptible to T/S than Clinda

Confers an especially high risk for C. diff disease compared to other antibiotics

Question 6

Lincosamides Good For

Answer 6

Skin/ss infections
Oral cavity
Anaerobic intra-abdominal

Used topically for acne

P. jirovecii pneumonia (2nd line agent in combination with primaquine)

Malaria (in combination with other drugs)

Bacterial vaginosis

Prophylaxis of bacterial endocarditis