From the HealingWell Panic Disorder Forum

It's enough of a problem that Wikipedia has a separate entry for "Munchausen by Internet". To quote them:

"The development of factitious disorders in online venues is made easier by the availability of medical literature on the Internet, the anonymous and malleable nature of online identities, and the existence of communication forums established for the sole purpose of giving support to members facing significant health or psychological problems. .... The virtual communities that were created to give support, as well as general non-medical communities, often express genuine sympathy and grief for the purported victims. When fabrications are suspected or confirmed, the ensuing discussion can create schisms in online communities, destroying some and altering the trusting nature of individual members in others."

A few points stood out in the article:

"The length and severity of purported physical ailments conflicts with user behavior.
Symptoms of ailments may be exaggerated as they correspond to a user's misunderstanding of the nature of an illness.
Grave situations and increasingly critical prognoses are interspersed with "miraculous" recoveries.
A user's posts eventually reveal contradictory information or claims that are implausible: for example, other users of a forum may find that a user has been divulging contradictory information about occurrence or length of hospital visits.
When attention and sympathy decreases to focus on other members of the group, a user may announce that other dire events have transpired."

Thanks for posting the thread: something all health forums should be aware of.