Gram Negative

Deadly bacteria defy drugs, alarming doctors
A new category of bugs becomes more resistant to treatment, and their toll -- which already includes a Brazilian beauty queen -- is expected to rise.
LA Times, 2/17/09

Move over MRSA, there's another bully on the block.

Acinetobacter doesn't garner as many headlines as methicillin-resistant Staphylococcus aureus, the dangerous superbug better known as MRSA. But a January report by the Infectious Diseases Society of America warned that drug-resistant strains of Acinetobacter baumannii and two other microbes -- Pseudomonas aeruginosa and Klebsiella pneumoniae -- could soon produce a toll to rival MRSA's.

The three bugs belong to a large category of bacteria called "gram-negative" that are especially hard to fight because they are wrapped in a double membrane and harbor enzymes that chew up many antibiotics. As dangerous as MRSA is, some antibiotics can still treat it, and more are in development, experts say.

But the drugs once used to treat gram-negative bacteria are becoming ineffective, and finding effective new ones is especially challenging.