Primary Nocturnal Enuresis

(Hong Kong—The Hong Kong Practitioner, November 2000, p. 539.) At the age of five years, about 7 percent of boys and 3 percent of girls have enuresis. The spontaneous remission rate is 5 to 10 percent per year after age five. The medical history should establish the occurrence of daytime wetting or soiling, and any associated medical, psychologic or family problems. Physical assessment should include the patient's developmental stage as well as an examination of the genitalia and back (to exclude spina bifida). A mid-stream urine sample should be examined for protein, glucose and evidence of infection. With a supportive family, most children respond well to educational approaches. Daytime bladder training, in combination with the use of a star chart reward system and enuresis alarm, is claimed to be successful in most cases. For resistant cases, two principal drug treatments are available. Imipramine, in a dosage of 25 to 75 mg per day, provides an inexpensive and effective treatment of enuresis. Some physicians recommend pretreatment electrocardiography because of rare reports of sudden cardiac death. Desmopressin, in a dosage of 0.2 to 0.4 mg at bedtime, has comparable effectiveness to imipramine, but is more expensive and is associated with hyponatremia.

Prophylaxis for Infective Endocarditis

(Canada—Canadian Family Physician, November 2000, p. 2248.) Bacterial endocarditis usually involves damaged heart valves, but can occur on any area of damaged endothelium. The infection is typically caused by transient bacteremia from infection in other areas of the body, such as pneumonia, or from instruments used during dental or other surgery. Established bacterial endocarditis has a mortality rate of approximately 37 percent and can lead to significant morbidity among survivors. Patients at high risk of bacterial endocarditis include those with prosthetic heart valves, congenital heart disease and previous history of bacterial endocarditis. Patients with cardiomyopathy and acquired valvular disease are generally at moderate risk. Patients with pacemakers, history of coronary artery bypass surgery, functional heart murmurs and acquired valvular disease without dysfunction are typically at negligible risk (no greater than the general population). In such patients, prophylaxis is not recommended. Prophylaxis is recommended in patients with mitral valve prolapse when a murmur is present and/or echocardiography shows mitral regurgitation. Amoxicillin in a dose of 2 g administered one hour before the procedure is currently recommended. Clindamycin in a dose of 600 mg is recommended for patients who are allergic to penicillin. Current recommendations do not include a second dose of antibiotic following the procedure.

Dermatitis Herpetiformis

(Canada—Canadian Family Physician, November 2000, p. 2199.) Dermatitis herpetiformis is an autoimmune skin condition in which deposits of IgA form at the epidermal-dermal junction. The condition is often associated with gluten sensitivity and gastrointestinal symptoms. Histologically, the papillary dermal tips are edematous and separate from the epidermis. Patients present with chronic, intensely itchy vesicles and pustules on the extensor surfaces of the arms and legs. As vesicles are broken, lesions can become crusted and secondarily infected. Chronic lesions may become hyper- or hypopigmented. Mucous membranes are usually not affected. Clinically, dermatitis herpetiformis can resemble scabies, atopic dermatitis or neurotic excoriations. Treatment with dapsone can dramatically improve the condition, and many patients also benefit from a gluten-free diet.

Management of Constipation in the Elderly

(Great Britain—The Practitioner, November 2000, p. 982.) Constipation in the elderly can have many causes and can take several forms. Management focuses on achieving appropriate stool consistency and maintaining control of bowel movements. Fiber can effectively soften stool, increase its bulk and stimulate defecation, but it may also increase flatulence and fecal incontinence in elderly per sons. Osmotic laxatives such as lactulose are effective alternatives to soften hard stools. Fecal loading can result in constipation and incontinence. The rectum and colon should be emptied, usually with the use of a suppository or enema, then appropriate laxative therapy should follow to prevent recurrence. Stimulant laxatives, such as senna and bisacodyl, act on the myenteric plexus and should be given at night when needed. However, they are not suit able for long-term use because they may cause myenteric plexus degeneration.