Bile acid malabsorption associated with Graves' disease

The efficacy of a low-fat diet to manage the symptoms of bile acid malabsorption - outcomes in patients previously treated for cancer

Dietary fat ingestion triggers bile secretion into the gastrointestinal tract. Bile acid malabsorption affects >1% of the population, causing loose stool and other gastrointestinal symptoms. The diagnosis is frequently missed. Treatments are often considered ineffective. We evaluated low-fat diets for managing gastrointestinal symptoms in these patients. All patients reporting type 6 or 7 stool were offered a selenium-75 homocholic acid taurine (SeHCAT) scan. Prospective data in patients with 7-day scan retention <20% were analysed. -Patients requiring a bile acid sequestrant were given this before receiving dietary advice. Patients completed a 7-day food diary before dietetic consultations. Personalised dietary interventions, providing 20% of daily energy from fat, were prescribed. Symptoms were assessed using a modified gastrointestinal symptom rating scale questionnaire before and 4-12 weeks after dietary intervention. A total of 114 patients (49 male, median age 64 years, median body mass index 27 kg/m2) were evaluated. 44% of these patients were taking colesevelam. After dietary intervention, there was statistically significant improvement in abdominal pain and nocturnal defecation (0.2% alpha, p=0.001). Improvement in bowel frequency, urgency, flatulence, belching, borborygmi and stool consistency were seen, but did not reach statistical significance (p≤0.004-0.031). Dietary intervention is an effective treatment option for patients with symptomatic bile acid malabsorption and should be routinely considered.

Drug-induced, factitious, & idiopathic diarrhoea

The aetiology of diarrhoea can often be simple to identify, but in some cases may pose a challenge. The diagnosis of drug-induced diarrhoea can easily be sorted based on timing of the symptom with onset of a new drug. Treatment can vary from simply monitoring and eventual resolution with continuation of the drug, to discontinuation of the offending agent. In cases where a drug cannot always be stopped, additional medications can help control the symptom. Factitious diarrhoea can present a diagnostic challenge if the evaluating physician does not suspect its possibility. Typically a careful history, and in some cases, stool testing can provide clues. The diagnosis of idiopathic diarrhoea is often made when exhaustive testing provides no definite aetiology and the goal of management is supportive care and symptomatic treatment.

Graves' disease with intractable diarrhea, chylous ascites, and chylothorax: a case report

A 50-year-old woman was admitted to our hospital because of severe diarrhea, irritableness, and severe pitting edema of the legs. The patient had been well until 5 years before admission, when a tremor and tachycardia developed and a diagnosis of Graves' disease was made. Treatment with methimazole was effective in reducing her tremor and tachycardia; however, she was often nonadherent with her antithyroid medication because of improvement of her symptoms. On admission, a thyroid swelling, exophthalmos, a pleural effusion, and ascites were observed. The results of thyroid function tests (free triiodothyronine: 21.5 pg/mL; free thyroxine: 7.17 ng/dL; thyroid-stimulating hormone (TSH): <0.01 microIU/mL; TSH receptor antibodies: 95.9%) were consistent with Graves' disease. Biochemical analysis of pleural and ascitic fluid was consistent with chylothorax and chylous ascites, respectively. Serum calcium, total protein, and albumin were very low. Her symptoms and signs except severe diarrhea, edema, pleural effusion, and ascites disappeared after receiving intravenous drip infusion of fluid replacement, and methimazole and iodine. Because of malnutrition, she was given a high-calorie intravenous infusion. Three months after admission, her pleural effusion and ascites began to improve, as did her diarrhea and hypoalbuminemia. An appropriate treatment of Graves' disease is crucial to avoid serious sequelae of longstanding, poorly controlled hyperthyroidism.

Intractable diarrhea in hyperthyroidism: management with beta-adrenergic blockade

OBJECTIVE

To describe a patient with intractable diarrhea and thyrotoxic Graves' disease, for whom b-adrenergic blockade ultimately proved to be effective therapy for the diarrhea, and to review the types of hyperthyroidism-associated diarrhea.

METHODS

We present the clinical course of a young man with a prolonged siege of diarrhea that proved elusive to diagnostic inquiries and resistant to all means of management until its endocrine basis was discovered. Control of such cases with b-adrenergic blockade is discussed, as are the pathophysiologic bases of intestinal hypermotility in hyperthyroidism.

RESULTS

A 26-year-old man with Down syndrome, and no prior gastrointestinal disorder, had insidious, chronic, constant diarrhea, which was associated with loss of 14 kg during a 5-month period. Numerous laboratory and imaging studies and endoscopic examinations failed to disclose the cause of the diarrhea. Furthermore, a broad range of antibiotics and other empiric remedies failed to control the problem. No other symptoms of hyperthyroidism were reported, but when the endocrinopathy was suspected and identified, the diarrhea was promptly controlled by treatment with propranolol. In patients with hyperthyroidism, two types of diarrheal disorders have been described-secretory diarrhea and steatorrhea; bile acid malabsorption may have a role in either of these settings.

CONCLUSION

In addition to its capacity for blocking the peripheral effects of thyroid hormone on the heart and central nervous system, b-adrenergic blockade is effective in slowing intestinal transit time and ameliorating the uncommon diarrhea associated with hyperthyroidism. Thyroid hormone in excess, among its other possible effects on the gastrointestinal tract, may exert a stimulatory effect by means of intermediary sympathetic activation, as it does with the heart. Thus, sympathetic blockade can mimic the salutary effects on the gastrointestinal tract conventionally brought about by direct antithyroid therapy, and well before the hyperthyroid state per se is eliminated. The current patient illustrates the value of considering hyperthyroidism in the differential diagnosis of diarrhea of unknown cause.