Differential diagnosis​

Undiagnosed major psychiatric disorder

Over half of patients with a major psychiatric disorder focus on, and are distressed by, the somatic symptoms that accompany these disorders rather than the distressing thoughts or emotions characteristic of the disorder. All psychiatric disorders have symptoms that are "above the neck" (i.e., cognitive and emotional symptoms) and "below the neck" (i.e., somatic symptoms).

The most common psychiatric diagnoses to present with physical symptoms are major depression (e.g., sleep disturbance, appetite disturbance, fatigue, pain) and an anxiety disorder. Panic disorder is the most likely anxiety disorder to present with somatic symptoms (e.g., palpitations, dyspnea, trembling, shaking, hot and cold flashes, lightheadedness).

Major psychiatric disorders associated with somatization include:

• major depression
• anxiety disorders:
  • panic disorder
  • generalized anxiety disorder
  • posttraumatic stress disorder
  • acute stress disorder
• substance use disorder

• psychotic disorders:
  • schizophrenia
  • delusional disorder – somatic subtype

Undiagnosed physical disorder

Patients may be preoccupied by their bodies because there is something medically wrong with them. Early presentations of a wide variety of diseases may be characterized by such non-specific symptoms as fatigue, decreased energy, sleep disturbance,abdominal discomfort, muscle aches, etc. Consider functional somatic syndromes.

Comorbidities

Patients with somatoform disorders have very high rates of comorbidity with other psychiatric diagnoses. Therefore, always screen for depression, panic disorder and generalized anxiety disorder. The likelihood of a given diagnosis in an individual patient varies considerably.

Factitious disorder and malingering

These are uncommon diagnoses. The patient who is somatizing experiences symptoms and is not involved in their production, in contrast to these two diagnoses where symptoms are intentionally produced for gain in malingering or for unconscious reasons (e.g., wish to occupy "sick role") in factitious disorder.