Actually, I was using an older definition of the word Syndrome: as in:
Syndrome: An incompletely described disease process; or a grouping of signs or symptoms that together describe a particular abnormality or condition that may be recurrent or chronic in nature.
Example: When AIDS was first documented as a disease, it was a Syndrome; as the mechanism of the disease was unknown and undescribed. It has since become a pathological disease; having been fully described.
In PItW, even the Were's themselves are unsure as to what makes them tick (as Werewolves). Some say it's a sort of super-virus, others say it's a spiritual condition. From what Kris has described, it acts like a virus; having an incubation period wherein the entire body is "infected" with a species-specific metamorphic condition before any physical manifestation takes place; but the gain of mass and the "un-growth" of the Were's fur suggests a spiritual situation-wherein the physical laws are temporarily suspended by spiritual means.
Personally, I think it's a case of chronic "Author-itis" -where the Author knows what it is, but chooses not to tell anyone else.
What the heck: I check my Physics major at the door and just enjoy the story as it is.