Discussion: JC’s pediatrician orders a comprehensive metabolic panel (CMP), hemoglobin A1C (HbA1C), and urinalysis, as well as a fasting insulin, glucose, and lipid panel. She is treated for her vaginal yeast infection. However, the urinalysis result shows large urine glucose, with no ketones. The HbA1C is 7.8, and the glucose on the CMP is 208. JC’s pediatrician speaks to a pediatric endocrinologist, who agrees that JC has type 2 diabetes mellitus (T2DM), and an outpatient appointment is arranged in the CHOP Diabetes Center for Children (DCC) within a week.
Increased childhood obesity has led to increased insulin resistance (IR) and T2DM in children (see box). T2DM may present by itself or as part of the metabolic syndrome (MS), which has also increased in prevalence in children, and is usually defined by having 3 to 4 of the following: obesity, IR, hyperglycemia, dyslipidemia, and hypertension (exact criteria vary). MS is associated with an increased risk for T2DM and cardiovascular disease. Thus, as obesity, T2DM, and its comorbidities occur more frequently in children, today’s young people are likely to become a population at risk for developing cardiovascular disease 20 to 30 years earlier than today’s adults. It is imperative that we recognize and treat T2DM in children aggressively.
T2DM is caused by both genetic and environmental factors. The pathophysiology of T2DM begins with IR and compensatory hyperinsulinemia. However, it also involves an insulin secretory defect, beginning with a loss of first-phase insulin secretion. Risk factors for T2DM include obesity (particularly visceral adiposity), IR, decreased physical exercise, increased sedentary activity (television, video games), race/ethnicity (increased in African-American, Native American, Asian, and Hispanic), and family history (74 to 100% of T2DM children have a close relative withT2DM). Adolescents also have decreased insulin sensitivity during puberty (due to increased growth hormone secretion), making this a common time for presentation.
The presentation of T2DM involves symptoms of hyperglycemia, including polyuria, polydipsia, and nocturia. Other consequences of hyperglycemia may include yeast infections and new-onset eneuresis. Physical findings often include obesity and signs of IR, such as acanthosis nigricans. Lab findings reveal serum hyperglycemia, glucosuria, and elevated HbA1C. Although less common, patients can present with ketonuria and even diabetic ketoacidosis.
In the case above, JC fits the first criterion. Note that the diagnosis is not based on HbA1C. Related comorbidities to T2DM include polycystic ovarian syndrome (for which JC’s history is concerning), dyslipidemia, nonalcoholic steatohepatitis (NASH), and hypertension (also seen in JC).
Treatment of T2DM aims at normalization of blood glucose, and is multifold. Lifestyle modification is crucial, and involves dietary changes and increased physical exercise to lose weight. Pharmacologic therapy includes different types of insulin (Lantus, 70/30, etc) and metformin, depending on the severity of presentation. Metformin is the only drug approved for use in pediatric T2DM, and it improves insulin sensitivity and decreases hepatic glucose production. Rare adverse effects include lactic acidosis and megaloblastic anemia. Common side effects include nausea, diarrhea, abdominal discomfort, and bloating. To prevent these, metformin dosing is increased gradually over weeks, to the target dose.
At diagnosis, families meet with a diabetes nurse practitioner, pediatric endocrinologist, nutritionist, and social worker to help support the family. Baseline labs include a CMP (including LFTs), urinalysis, diabetes autoimmune panel (to rule out T1DM), fasting insulin and C-peptide, IGF-BP1, and a thyroid panel, fasting lipid panel, and HbA1C. If metformin initiation is planned, CBC, transaminases including GGT, and urine pregnancy in girls are also performed at baseline and followed while on treatment. At CHOP, new patients with T2DM with HbA1C > 8.5 are admitted to the hospital for initiation of insulin therapy and intensive family education. After the resolution of any acidosis, metformin treatment is also initiated. For new T2DM patients such as JC, with HbA1C <8.5, treatment is initiated at the outpatient DCC clinic, usually with metformin and lifestyle changes. If needed, insulin may be added in the future. T2DM and glucometer teaching takes place as an outpatient through the DCC Education Center. T2DM treatment also includes treatment of comorbidities, such as hypertension, dyslipidemia, NASH, and PCOS.
Patients with T2DM are followed in the CHOP DCC with appointments every 2 months with their diabetes provider and nutritionist, and with the social worker as needed. Blood glucose records and HbA1C are followed over time, and treatment adjusted as needed. Patients undergo yearly screening for complications such as nephropathy (urine microalbumin/Cr ratio), neuropathy, retinopathy (dilated eye exam), evidence of cardiovascular disease (fasting lipid panel), and NASH (transaminases). The goal for T2DM patients is to optimize blood sugar control in order to prevent long-term complications.
References and Suggested Readings
American Diabetes Association. Type 2 diabetes in children and
adolescents. Diabetes Care. 2000;23:381-9.
Pinhas-Hamiel O, Zeitler P. Clinical presentation and treatment of
type 2 diabetes in children.
Pediatr Diabetes. 2007 Dec;8 Suppl 9:16-27. Review.
Discussion: TS is an 11-year-old girl presenting for well-child care. You have seen her on a regular basis since birth and note that over the past few years her weight has started to increase. In the past, you offered advice about healthy eating and exercise because you knew she was at risk for developing obesity, given her 2 risk factors: her BMI has crossed 2 major percentile curves and her mother is obese. Now, at age 11, she is above the 95th percentile for BMI, which puts her in the diagnostic category for obesity. You use the guidelines from CHOP’s Healthy Weight Program to assist your assessment for identification, evaluation, and management for obesity. (The guidelines are available at here).
In addition to your routine history, you elicit positives for family history including obesity in both biological parents, early heart disease, and a negative history for diabetes and hyperlipidemia. Her lifestyle history reveals a pattern of skipping breakfast, frequent high-fat foods, fewer than 5 servings of fruits and vegetables a day, more than 8 ounces of fruit juice a day, no high-sugar drinks since she has cut out soda and iced teas, a TV in her bedroom with more than 2 hours of screen time a day, daily walks to and from school, and no organized sports. Concerned about major comorbidities associated with obesity, (diabetes, slipped capital femoral epiphysis and Blount’s disease pseudotumor cerebri, psychological issues, and sleep apnea) your review of systems reveals that she denies polydipsia and polyuria, and denies joint pain, frequent headaches, or teasing about her weight, but she does have nightly snoring and daytime sleepiness.
On her physical exam you pay special attention to associated comorbidities and find a blood pressure which is in the normal percentile range for her height, age, and gender; no papilledema; her skin shows no acne, hirsutism, striae, or evidence of candida infection but is positive for acanthosis nigricans; and a normal joint exam.
Strength in Numbers
The Healthy Weight Program at CHOP is a resource for clinicians, providing clinical education and information to help you promote healthy lifestyles for your patients. Our new Strength in Numbers campaign promotes good nutrition and healthful activities for the entire family. Please see the area for Healthcare Professionals at www.chop.edu/healthyweight to download campaign flyers, recipes, and lifestyle toolkits you can use to help families make healthy changes. If you’d like some of the campaign’s kid-friendly stickers and posters for your office, please contact the Healthy Weight Program at 215-590-4996.
A laboratory evaluation will help determine other comorbidities, including fasting blood glucose to determine diabetes or pre-diabetes, fasting lipid panel to determine dyslipidemias, and liver enzymes for nonalcoholic fatty liver disease.
You know behavior modification is necessary for intervention, so you assess TS and her mother’s readiness to change and their willingness to work on one of the 8 behavior tools found at www.chop.edu/healthyweight in the Lifestyle Toolkits section of the Healthcare Providers area. TS and her mother are eager to work on eating structured meals. You review the 4-page toolkit, including information, tips, a contract, and monitoring forms. You arrange to refer her for a sleep study for her possible sleep apnea, will call her with the results of her lab work, and arrange to see her back in 4 to 6 weeks.
Her fasting blood glucose is back at 115 and she qualifies for a diagnosis of pre-diabetes. While weight management and exercise are the mainstay of treatment at this stage, one may want to refer to an endocrinologist at this point for assistance in management and follow-up.
The epidemic of obesity is well known to pediatricians. The treatment is multifaceted and involves communities, schools, government policy, individuals, and families, as well as pediatricians. In the office, we can start by using BMI percentile to appropriately identify obesity in children and screen for weight-related comorbidities.
We can also initiate treatment by partnering with patients and families to teach and adopt behavior modification skills. Empowering families with these tools is a step toward encouraging healthier choices.
Through research, we know there are at least 8 lifestyle areas amenable to behavior change that result in healthier lifestyle, reduced comorbidities and healthier BMIs. Making these changes is not always easy and requires behavior modification approaches, such as goal-setting, role-modeling, self-monitoring, stimulus control, preplanning, cognitive restructuring, and positive reinforcement.
While there is not a large body of evidence to guide us about obesity prevention, the general consensus is that prevention starts with making healthy choices as early as possible, starting with exclusive breastfeeding for the first 6 months of life.
Focusing on key target behaviors based on the 5-2-1-0 message (see box above), we can support families in living healthy lifestyles from the start — promoting overall health and prevention of obesity.
References and Suggested Readings
Barlow SE and the Expert Committee. Expert Committee
Recommendations Regarding the Prevention, Assessment, and
Treatment of Child and Adolescent Overweight and Obesity:
Summary report. Pediatrics. 2007;120:S164-S192.
Discussion: This child presents with hyperphagia and obesity, hypotonia and developmental delays. The pattern of poor feeding in infancy and hyperphagia in early childhood, hypotonia, and hypogonadism suggests Prader-Willi syndrome (PWS). PWS is associated with chromosome 15q11 abnormalities, a region showing evidence of “imprinting,” or differential expression based on parental origin. In PWS, part of paternal chromosome 15q11 is absent. This can occur by a deletion within the paternal chromosome in 70% to 75% of cases. Another 25% have 2 copies of maternal chromosome 15, and no paternal contribution, a mechanism known as uniparental disomy, or UPD. The vast majority of PWS cases (>95%) can be confirmed by molecular cytogenetic testing of a blood sample using either FISH (fluorescence in situ hybridization) to test for a deletion, or PCR-based methylation testing to detect UPD, since imprinted chromosomes show different methylation patterns. PWS occurs primarily de novo, and has a low recurrence risk in either of these 2 mechanisms. Higher risks occur in rare defects of the imprinting center, and specific directed testing is required to ascertain this mechanism.
This child has several distinctive clinical findings of PWS, including infantile central hypotonia with poor suck that improves with age. Poor movement in utero fits this pattern as well. Decreased lean body mass and hyperphagia with resulting central obesity is characteristic. Short stature is also present. The facial features described above, and genital hypoplasia, primarily of the labia and clitoris in females and the scrotum in males, are common. Cryptorchidism is typical. Small hands and feet are also seen in this disorder. Delays in gross motor skills, speech, and cognitive impairment are typical. Behavioral features include tantrums, obsessive-compulsive behaviors, and uncontrolled food-seeking, particularly in adolescence, that can require locking away food at night.
The differential diagnosis includes Bardet-Biedl syndrome (BBS) with truncal obesity, cognitive impairment, and hypogonadism. The facial features differ from PWS, however, and post-axial polydactyly of the hands is seen in BBS. An ophthalmologic referral and electroretinogram are warranted for this disorder due to an associated cone-rod dystrophy. There is diagnostic testing for many of the causative genes for BBS. The underlying defects involve abnormalities in structure and transport functions of cilia.
Angelman syndrome can include developmental delay and obesity, though hyperphagia and hypogonadism are not typical. Angelman patients tend to have seizures, jerky movements, and autistic spectrum behaviors such as flapping, minimal speech, and characteristic bursts of laughter. This disorder localizes to the same genomic region as PWS but is on the maternal copy of chromosome 15q11.
Less commonly, Fragile X syndrome and Albright hereditary osteodystrophy can overlap PWS, with developmental delay/mental retardation and obesity. However, these disorders are phenotypically distinct from PWS, and specific molecular diagnostic testing is available to differentiate them. It is interesting to note that craniopharyngioma and its treatment show overlap with PWS, attributable to hypothalamic damage that recapitulates the lack of satiety, short stature and hypogonadism.
In addressing the obesity-related issues of PWS, early diagnosis is beneficial. Early intervention and physical therapy can improve muscle strength and increase lean body mass, which is particularly affected in PWS. When hyperphagia begins (often at ages 2 to 4) close supervision of diet, exercise, and behavioral therapies can help. Uncontrolled, the obesity results in associated diabetes and cardiovascular disease at an
early age. Recently, growth hormone therapy initiated in late infancy and early childhood, at dosages typically used for deficiency, has been shown to help height, increase lean body mass, and benefit mobility and motor development. A formal sleep study is recommended prior to initiating growth hormone treatment since sleep apnea can be exacerbated during therapy.
References and Suggested Readings
Cassidy S, and Schwartz S. Prader-Willi Syndrome, in Gene
Reviews (National Library of Medicine Bookshelf ), article can be
Online Mendelian Inheritance in Man (OMIM #176270).
Prader-Willi Syndrome in Jones KL. Smith’s Recognizable Patterns
Of Human Malformation Sixth Edition, Philadelphia:W. B.
Ricardo is a 12-year-old boy who presented for well-child care to the Puentes de Salud clinic. Ricardo was born in Mexico and moved to Philadelphia with his mother 2 years ago. Ricardo is generally healthy, but his mother noted that he has “filled out” since relocating to the United States. On a growth chart, Ricardo’s body mass index is in the 90th percentile for his age. The clinician’s description of Ricardo as “overweight” surprised his mother and stimulated a discussion about lifestyle change.
Preventing and treating obesity in a resource-limited immigrant population presents a variety of challenges. Urban immigrant communities face many of the same challenges as other impoverished urban families, including limited access to affordable, healthy foods and safe places for children to play. And immigrant communities often face additional sociocultural barriers. Dietary staples for many immigrant communities, such as white rice and starchy vegetables, are often high in caloric density. Families may hesitate to substitute traditional staples for new—and often pricier—foods. Undocumented immigrants face particular challenges with food security, due to erratic employment with insufficient wages. As immigrants transition from food insecurity to food security, many perceive the risk of not providing for one’s children as more harmful than obesity, and it is difficult to suggest limiting a child’s diet.
None of the stores at which Ricardo’s mother shops sells brown rice, a healthier alternative to white rice. Her long work hours often preclude her from preparing meals daily for her son, so she often relies on fast food for her child. During the discussion, Ricardo and his mother agreed that minimizing juice consumption, working on portion control, and engaging in weekend family outdoor activities would be realistic initiatives for lifestyle change.
In an increasingly diverse America, pediatricians must be attuned to economic and sociocultural barriers when preventing and treating obesity. Providers must help families determine where they are willing to make changes and what changes are unacceptable or unrealistic. Immigrant families in particular may benefit not only from treatment strategies once children are overweight or obese, but from preventive strategies that help them to make healthy choices as they integrate into a new society.
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