For all psych disorders- you should look to the DSM-IV. Or for the quick and dirty version, e-medicine articles are usually pretty good (try google).
For patients that have hypochondriasis:
(1) The patient has a preoccupying fear of having a serious disease.
(2) The preoccupation persists despite appropriate medical evaluation and reassurance.
(3) The belief is not of delusional intensity (as in delusional disorder, somatic type) and is not restricted to a concern about appearance (as in persons with Body dysmorphic disorder).
(4) The preoccupation causes clinically significant distress or impairment.
(5) The preoccupation lasts for at least 6 months.
(6) The preoccupation is not explained better by another mood, anxiety, or somatoform disorder.
Factitious Disorder:
(1) intentional production or feigning of physical or psychological signs or symptoms,
(2) motivation for the behavior is to assume the sick role, and
(3) absence of external incentives for the behavior (eg, economic gain, avoiding legal responsibility, improving physical well-being, as in malingering).
Munchuasen's is a form of factitious disorder wherein the patient is motivated to assume the sick role (or caregiver for a sick person- by proxy subtype).
For patients with Munchausen's. Keep in mind that there are types including Munchausen's by proxy with the classic case of the mother making her child ill to get attention for herself. For cases involving the patient directly:
(1) Dramatic presentations of apparently severe illnesses
(2) Reported symptom patterns that fit diagnoses too perfectly and are too much like a textbook presentation
(3) A history of extensive surgical procedures and inpatient workups for a variety of diseases, particularly when the workup spans multiple hospitals and cities
(4) Notable vagueness or inconsistency in the details of the medical problems
(5) Evidence of pathological lying in areas other than the presenting symptoms
