A somatoform disorder can not be better accounted for by a mood, anxiety, or psychotic disorder. Pain has a neurophysiological sensory component, which signals that tissue insult is occurring, and a perceptual, psychological component, which affects the subjective experience of pain. However, the diagnosis of pain disorder rests not only on the physician s inability to fully explain the pain on an organic basis, but also on the clinical implication of the role of psychological factors. The specific frequency of pain disorder in children, is unknown at this time. In recurrent abdominal pain, nonspecific inflammatory changes can be found on biopsy at all levels of the GI tract, suggesting that immunomodulation plays a role in the pathogenesis of the symptom.
Emotional distress can cause muscular pains and headaches through increased muscular tension.
Psychologically induced changes in behavior, such as compulsive activity or prolonged bed rest, lead to secondary physiologic changes and attendant symptoms. Ethnic groups may differ in the acceptability of expressing discomfort and in the value placed on pain tolerance. Medically unexplained somatic symptoms are more frequent in girls than in boys. Differences in pain threshold have not been noted, but with increasing age, girls report pain and seek relief more readily. Children experience pain no less intensely than adults, while children younger than 8 years express more overt distress.