Sometimes, the anxiety may not be judged to be excessive, because it is related to an actual danger (e.g., being bullied or tormented by others). However, individuals with social anxiety disorder often overestimate the negative consequences of social situations, and thus the judgment of being out of proportion is made by the clinician. The fear, anxiety, or avoidance is persistent, typically lasting for 6 months or more. This duration threshold helps distinguish the disorder from transient social fears that are common, particularly among children and in the community. However, the duration criterion should be used as a general guide, with allowance for some degree of flexibility. The fear, anxiety, or avoidance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning. The fear, anxiety, and avoidance must interfere significantly with the individuals normal routine, occupational or academic functioning, or social activities or relationships, or must cause clinically significant distress or impairment in social, occupational, or other important areas of functioning. For example, an individual who is afraid to speak in public would not receive a diagnosis of social anxiety disorder if this activity is not routinely encountered on the job or in classroom work, and if the individual is not significantly distressed about it. However, if the individual avoids, or is passed over for, the job or education he or she really wants because of social anxiety symptoms criterion is met.
Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated colon (megacolon), accompanied by abdominal distension (bloating), and sometimes fever, abdominal pain, or shock. Toxic megacolon is usually a complication of inflammatory bowel disease, such as ulcerative colitis and, more rarely, Crohns disease, and of some infections of the colon, including Clostridium difficile infections, which have led to pseudomembranous colitis. Other forms of megacolon exist and can be congenital (present since birth, such as Hirschsprungs disease). It can also be caused by Entamoeba histolytica and Shigella. It may also be caused by the use of loperamide. Signs and symptoms
Abdominal pain
Abdominal bloating
Abdominal tenderness
Fever
Tachycardia (rapid heart rate)
DehydrationThere may be signs of septic shock. A physical examination reveals abdominal tenderness and possible loss of bowel sounds. An abdominal radiography shows colonic dilation. White blood cell count is usually elevated. Severe sepsis may present with hypothermia or leukopenia. Complications
Perforation of the colon
Sepsis
ShockEmergency action may be required if severe abdominal pain develops, particularly if it is accompanied by fever, rapid heart rate, tenderness when the abdomen is pressed, bloody diarrhea, frequent diarrhea, or painful bowel movements. Colonoscopy is contraindicated, as it may rupture the dilated colon resulting in peritonitis and septic shock. Pathophysiology
The pathological process involves inflammation and damage to the colonic wall with unknown toxins breaking down the protective mucosal barrier and exposing the muscularis propria. There is relative destruction of the ganglion cells and swelling of the nerve fibers in the myenteric plexus, with concomitant damage to the colonic musculature.