The medical and financial impact of diabetes mellitus (DM) in children cannot be overstated. Type I DM (formerly referred to as insulindependent DM) is the second most prevalent chronic disease of children, and affects more than 130,000 children in the United States alone.1 DM decreases life expectancy and is associated with long-term complications, which pediatricians do not commonly see. Nevertheless, the prevention of these complications is an important, lifelong effort that begins during childhood.
Most cases of DM present before 15 years of age, and are diagnosed by the general pediatrician. Care is then provided by a team that includes the pediatric endocrinologist, dietician, community health nurse, and social worker. The pediatrician must learn to be an integral part of this team. This is essential to provide a unified message, to avoid confusion and frustration, and to strengthen the family's trust, especially in the beginning when many families are overwhelmed.
Education for newly diagnosed patients is now routinely provided through outpatient programs, which increase the need for the pediatrician to be involved. Most follow-up appointments will be with the pediatrician, whereas the endocrinologist may only review the case once or twice a year. For these reasons, the pediatrician will be faced with the day-to-day issues of case management, including hyperglycemia, hypoglycemia, sick days, and ketonuria.
The results of the Diabetes Control and Complications Trial (DCCT) have changed the treatment of diabetes in children. Although only 14% of the patients were between 13 and 17 years of age, the DCCT revealed significant reductions in retinopathy and microalbuminuria for intensively treated adolescents. Intensive treatment also prolonged the "honeymoon" phase for many other adolescents. Unfortunately, hypoglycemia and obesity were more frequent. Given the risks, the practitioner must evaluate each case before intensifying treatment. It may not always be practical or safe for children to attempt intensive therapy. Fortunately, the DCCT showed that every 10% reduction in hemoglobin Alc, at any level, decreases the risk of retinopathy by 40%.2
It is easy to focus entirely on glycémie control, but the primary care physician should consider other issues as well. Retinopathy, autoimmune diseases such as hypothyroidism, and microalbuminuria should be evaluated on an annual basis.3 It is important to recognize and address the psychological impact of this disorder and to provide nutritional assistance for the required dietary modifications.
Many studies have examined the etiology of DM and prevention trials are currently under way. At this point, however, we do not have a cure. The general pediatrician has an important and ever-increasing role in coordinating the care required for these patients and in managing the acute and chronic complications.
In contrast to the emphasis provided to type I DM during pediatric education and training, little time is spent learning how to deal with type ? DM (formerly referred to as non-insulin-dependent DM). Recently, however, type ? DM has assumed increasing importance. Studies from all regions of the United States suggest that the incidence of type II DM in children may be dramatically increasing, particularly in minority populations.4 In addition, retinopathy and nephropathy occur in type II DM just as they do in type I DM.
Type II DM is defined as any form of DM in which insulin is not required for survival but may be required for adequate glycémie control. Diabetic ketoacidosis is uncommon, but may be elicited by stress and does not exclude the diagnosis. Similarly, autoimmune ß-cell destruction is not characteristic of type II DM, but the presence of islet or insulin autoantibodies does not exclude the diagnosis of type II DM either. The clinical presentations of type I and type II DM are similar and the classic triad of polyuria, polydipsia, and polyphagia is observed in both forms of DM. For these reasons, type II DM can be difficult to recognize in children.
The National Diabetes Data Group and the World Health Organization Expert Committee on Diabetes offer the following criteria for the diagnosis of type II DM: insulin levels are normal, elevated, or depressed; hyperinsulinemia with insulin resistance; not insulin-dependent or ketosis-prone under normal circumstances, but may use insulin for control of hyperglycemia; onset at any age but predominantly after age 40; and tendency toward obesity. Youth-onset type II DM refers to individuals younger than 21 years of age who meet these criteria.
Perhaps the most useful features to distinguish type II DM in children are obesity, acanthosis nigricans (hyperpigmentation and thickening of the skin at flexural folds such as the neck and axillae), and a strong family history of adult-onset DM. Although type II DM is multifactorial, the genetic predisposition is even greater than for type IDM.
Not much is known about the optimal management of type II DM in young patients. Therapeutic options are grouped into three broad categories: (1) weight control through diet and exercise; (2) oral hypoglycemic agents; and (3) insulin. Diet and exercise are recommended as the initial approach, with oral hypoglycemic agents and, finally, insulin if hyperglycemia remains uncontrolled. Insulin may be required earlier in patients with severely impaired insulin action that is characterized by ketosis, weight loss, or symptomatic glyosuria. However, the efficacy of new drugs for the treatment of type II DM, such as metformin hydrochloride and troglitazone, has yet to be realized.
Type II DM in childhood represents a heterogeneous group of disorders with different pathophysiologic mechanisms. It was once believed to be a disease of predominately obese adults, and children with type ? DM were referred to adult endocrinologists for treatment. It is apparent that, as the incidence of type ? DM continues to increase in children, we as primary pediatricians must be able to identify and manage this disease. One of the goals of this issue is to provide pediatricians with the tools required to correctly diagnose the hyperglycemic child. In addition, this issue renews pediatricians' familiarity with the treatment of type ? DM.
1. Kaufman F. Diabetes in children and adolescents: areas of controversy. Med Clin North Am. 1998;82:721735.
2. Tamborlane W, Ahern J. Implications and results of the Diabetes Control and Complications Trial. Pediatr Clin North Am. 1997;44:285300.
3. Bennett P, Haffner S, Kasiske BL, et al. Screening and management of microalbuminuria in patients with diabetes mellitus: recommendations to the Scientific Advisory Board of the National Kidney Foundation from an ad hoc committee of the Council of Diabetes Mellitus of the National Kidney Foundation. Am J Kidney Dis. 1995;25:107-112.
4. Jones KL. Non-insulin dependent diabetes in children and adolescents: the therapeutic challenge. Clin Pediatr. 1998;37:103-110.
The opinions or assertions contained herein are the private views of the authors and are not to he construed as official or as reflecting the views of the Uniformed Services University of the Health Sciences, the Department of the Army, the Department of the Navy, or the Department of Defense.