What is "Cat Scratch Disease"?

QUESTION: A friend of mine (age 18) recently had what his doctor believed was
a cancerous tumor removed from his neck. Later tests revealed that he in fact
had "Cat Scratch Disease". What is this and how does one get it? Thank you
for satisfying my curiosity!
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ANSWER: At least your story has a happy ending, but strange lumps and masses
that develop anywhere on the body deserve a full investigation. Cat Scratch
Disease is not that rare, with about 2,000 cases reported each year in the
United States alone, usually occurring in the fall or winter months. It is an
infection caused by a gram-negative bacteria, and most frequently produces a
swelling in a single lymph gland. Children are the usual victims, and
kittens, which scratch more readily, are reported as the offenders in a large
number of cases. A few days after even a small scratch, a liquid-filled
pimple develops at the scratch site, which may last for several weeks.
Approximately two weeks later, a lymph gland, in the area near the scratch,
will begin to swell, sometimes growing as large as a golf ball. When they are
firm, they may resemble a tumor, and when the patient isn't the owner of the
kitten, and has forgotten about the little scratch inflicted perhaps three
weeks before, the physician may suspect a cancer. There are no blood tests to
aid in the diagnosis, but a careful examination of the tissue under a
microscope will make the diagnosis clear. Although the swelling may be
accompanied by slight fever and headache, it is a mild episode that passes by
itself. No treatment is necessary, and even antibiotics do not help. It may
take from 2 to 5 months for the swelling to disappear completely, without
lasting effects.