Categories: Infectious Diseases

Why give Clindamycin with a Beta-lactam for Group A Strep?

Why give Clindamycin for a Group A Strep infection that is already adequately covered by a Beta-lactam?

Proposed rationale: Clindamycin blocks 50s ribosomal subunit and therefore inhibits bacterial protein synthesis. It is thought that this will reduce endo/exotoxin production which is how Streptococcus pyogenes elicits its pathogenic effect. (It also increases opsonization and phagocytosis by inhibiting M-protein synthesis). Hence, it will act synergistically with the Beta-lactam (which is destroying the cell wall) to reduce the amount of toxin that is subsequently released into the blood. Clindamycin has a longer postantibiotic effect than penicillin.

The exotoxins of group A streptococci include the erythrogenic toxins (pyrogenic exotoxins) and the cytolytic toxins (streptolysins S and O)

References

1. Stevens DL. Streptococcal Toxic-Shock Syndrome: Spectrum of Disease, Pathogenesis, and New Concepts in Treatment. Emerg Infect Dis. 1995, Sept. Available from http://wwwnc.cdc.gov/eid/article/1/3/95-0301

 2. Marek, S. Current indications for the use of clindamycin: A critical review. Can J Infect Dis. 1998 Jan-Feb; 9(1): 22–28. 

3. Kalyan S, Chow AW. Staphylococcal toxic shock syndrome toxin-1 induces the translocation and secretion of high mobility group-1 protein from both activated T cells and monocytes. Mediators Inflamm. 2008. 2008:512196.

Get Medical Pearls directly to your inbox every week!
Weekly posts with high yield medical knowledge, directly to your mailbox!
Dr. C Humphreys

Internal Medicine

Share
Published by
Dr. C Humphreys

Recent Posts

Nocturia and OSA: Mechanism

Nocturia is a common symptom associated with obstructive sleep apnea. [1] Img Cred: Am J…

1 year ago

ASD vs. VSD Murmur Difference

ASD (Atrial Septal Defect) Wide, Fixed split S2 (in contrast to the normal variation in…

1 year ago

Mechanism of a Mixed Apnea

Mixed apneas are characterized by absent respiratory effort and airflow in the first section of…

2 years ago

How Does Hypothyroidism Cause Hypoventilation?

Although rare, the differential diagnosis of hypoventilation and hypercapnia respiratory failure includes hypothyroidism. It is…

2 years ago

Why is Pro-BNP/ BNP lower in Obesity?

B-type natriuretic peptide (BNP) is a hormone created in response to cardiac wall stretch due…

3 years ago

What is Peribronchovascular Distribution on CT imaging?

A common finding described on computed tomography (CT) imaging. A disease with a peribronchovascular distribution…

3 years ago

This website uses cookies.