A 26 year old graduate student presents with episodic mucoid diarrhea for 1 year. This is associated with abdominal discomfort, which is relieved by defecation. There is no history of fever, bloody diarrhea, vomiting, weight loss, joint pains or a skin rash. Nor is there a family history of gastrointestinal disorders. She also complains of fatigability, restlessness throughout the day, difficulty in sleeping, and difficulty concentrating on her studies. She constantly worries about her family, studies, and finances, and fears being involved in a car cash or being mugged, despite the absence of such events in her past. There is no history suggestive of suicidal ideation, panic attacks, depression, obsessive-compulsive behaviour, social phobia, or eating disorders. She has been thoroughly investigated by a gastroenterologist, but despite numerous investigations, including multiple endoscopies and a thyroid profile, no organic or functional cause for her diarrhea could be identified. She is not on any medications right now, and does not smoke, drink, or use recreational drugs.
WBC: 9,800/mm3 (4,500-10,500) N: 64% L: 32% Hb: 13.6 g/dL (12.0-15.0) Plt: 200x10^3/mm3 (150-450x10^3) ESR: 9 mm/hr (0-29) CRP: <1 mg/dL (<1)
Total T3: 100 ng/dL (75-200) Total T4: 6.5 µg/dL (4.5-11.5) TSH: 1.2 U/mL (0.3-5.0)
Blood Urea Nitrogen: 10 mg/dL (7-20) Creatinine: 1.0 mg/dL (0.8-1.4) Glucose: 90 mg/dL (64-128) K+: 4.0 mEq/L (3.5-5.3) Na+: 139 mEq/L (135-145) Cl-: 105 mmol/L (100-110)
Her urine drug screen is negative.