What organism most commonly causes mastitis?

Mastitis is most commonly caused by Staphylococcus, particularly Staphylococcus aureus. This bacterium is often found on the skin and can enter the breast tissue through cracked or sore nipples, leading to inflammation and infection. Staphylococcus aureus is known for its ability to form biofilms and produce toxins, which can complicate the infection and make it difficult to treat.

While other organisms such as E. coli and Streptococcus can also be implicated in mastitis, they are less common culprits compared to Staphylococcus. E. coli tends to be associated more with cases of mastitis that arise from environmental exposure or contaminated milk supplies, and Streptococcus species, including Streptococcus agalactiae, are also known pathogens but are not as prevalent as Staphylococcus aureus in typical cases of mastitis. Enterococcus is involved in some forms of infection but is even less frequently associated with mastitis than the other bacteria listed. Understanding the predominant role of Staphylococcus helps in guiding appropriate treatment and management strategies for mastitis.