Gram positive Bacillus. Group consists of Bacillus cereus, Bacillus mycoides, bacillus pseudomycoides, Bacillus thuringiensis and Bacillus weihenstephanensis.
Found worldwide in soil. B.cereus are commonly found in places where there is improper food handling.
Even though Bacillus is most often encountered in the laboratory as a contaminant, it can be associated with food poisoning, sepsis in IVDU.
B. cereus has been implicated as a major cause of post-traumatic endophthalmitis, and can result in blindness due to fulminant infection.
Rarely, B. cereus has been a cause of endophthalmitis after cataract surgery.
The infection usually progresses rapidly over the course of 24 to 48 hours, requiring enucleation, despite aggressive treatment with appropriate antimicrobial therapy. Clinically, this may present as a ring corneal infiltrate or corneal ring abscess.
B. cereus elaborates several exotoxins responsible for the rapid, acute retinal necrosis that occurs, which may account for the ineffectiveness of antimicrobial therapy.
Treatment requires vitrectomy with intra-vitreal injections of appropriate antimicrobials such as vancomycin or clindamycin.
