Are the surgical site infections "in the brain" caused by same bacteria found in "other parts of the body"?

Question

Are the surgical site infections "in the brain" caused by same bacteria found in "other parts of the body"?

1. There's a blood-brain barrier so, most of the bacteria that infect lungs won't reach the brain. But when you do a surgery in the brain it gives direct access to the bacteria, let's say Pneumocystis jirovecii which infect lungs, got in through a contaminated tool to the brain. So, can it infect the brain? Or it just can't survive in the brain as it's mostly thrive in lungs?

2. Are there any brain specific bacteria that can only infect brain but not the other parts of the body such as lungs?

Answer 1

The predominant organism was coagulase-negative staphylococci, of which most were methicillin-resistant coagulase-negative staphylococci (MRCoNS). All were susceptible to vancomycin, linezolid, rifampicin and amoxicillin-clavulanate. Acinetobacter baumannii was the most frequent causative Gram-negative agent and was resistant to 12 out of 18 antimicrobials tested.

Species of CoNS that have important traits and are more frequently associated with clinical disease are S. epidermidis (biomaterial-based and prosthetic device infections), S. lugdunensis (skin and soft-tissue infections, bacteremia, endocarditis), S. saprophyticus (uncomplicated urinary tract infections in sexually active women), and S. haemolyticus (often less-susceptible to vancomycin).

Many of these organisms are present as commensal on the skin. They pop up in other infections as mentioned above.

PJP seems to me to be an unlikely candidate because most people have it already without incident. It does not tend to cause harm except in immunocompromised people as mentioned on its wikipedia page. It is also a fungus, not a bacterium.