Full of life and joy, the 6-year-old was just about quivering with excitement waiting for her annual checkup to get under way. The little girl was all smiles, ready to talk about her fabulous life as a kindergartner. She also knew that this was going to be a pleasant visit since she had already received her required school shots during last year's physical exam.
I pulled out the girl's growth chart and shared with mom that the child was growing steadily in both height and weight. Of some concern, however, was that the girl was of average height, but well above the average weight for her age. Her body mass index value placed her at or above the 95th percentile, which put my little patient in the Centers for Disease Control and Prevention's "obese" weight status category.
Faced with those numbers, I started delving into family history, eating habits and level of physical activity. Grandmother had Type 2 diabetes, but no other close relatives were affected. The little girl ate well with a balanced diet high in fruits and vegetables and low in meat. Portion sizes were reported as average, and the 6-year-old did not overindulge in milk, rarely had juice and never drank carbonated beverages.
As far as physical activity, the mother said that her child never sat around, but was in a constant state of motion, playing inside or out from dawn until dusk. With no evidence of any lifestyle missteps, I was a bit stumped as to what I could ask the family to modify to help the child even out her height-to-weight ratio and maintain good health.
We moved on to the exam, and the child really looked great. Mom asked me to pay special attention to dark marks along the folds between her thighs and torso. These dark areas were on the front and the back of the upper thighs, and when I lifted the girl's long locks, the back of her neck also appeared darker than the surrounding skin.
The mother tugged down on her own shirt collar, showing me that she too had darker areas around her neck. Mom and I discussed the implications of these skin findings, known as acanthosis nigricans, combined with her daughter's elevated BMI, and the positive family history of Type 2 diabetes.
My patient was also a member of one of the racial and ethnic groups that the CDC considers to be at high risk for Type 2 diabetes -- African Americans, Hispanic/Latino Americans, American Indians, Asian-Americans and Pacific Islander Americans.
While I reassured the mother that none of these individual findings were diagnostic, when put together, they did indicate a higher risk for the future development of Type 2 diabetes. Mom and I agreed that the child would benefit from a consultation with a pediatric endocrinologist to further evaluate her unexplained weight status and her potentially prediabetic physical features.
Type 2 is the most common form of diabetes. The American Diabetes Association explains that in Type 2 diabetes, either insufficient amounts of insulin are produced by the body or the cells "ignore" the insulin that is present, a state referred to as "insulin resistance."
In their article published in the Dermatology Online Journal, Dr. Steven P. Higgins and his Duke University colleagues describe acanthosis nigricans as a velvety, brownish-black skin plaque commonly linked to obesity and insulin resistance. The presence of AN heightens suspicion for conditions such as Type 2 diabetes, the metabolic syndrome and polycystic ovary syndrome.
Among children with AN, the Duke team reports that the dark plaques are most often seen at the neck area (99 percent) or the armpits (73 percent), but can also develop on the eyelids, lips, vulva, mucous membranes and back of the hands, as well as in the folds of the groin, knees and elbows.
Higgin's group notes that AN may improve with the treatment of underlying conditions. While no large clinical trials have been done on the treatment of acanthosis nigricans, case reports show some treatment success with the use of topical and oral retinoids, topical calcipotriol, oral fish oil and laser therapies.
• Dr. Helen Minciotti is a mother of five and a pediatrician with a practice in Schaumburg. She formerly chaired the Department of Pediatrics at Northwest Community Hospital in Arlington Heights.