Short Stature Work-up Influenced by Gender

Abstract

Source: Grimberg A, Feemster KA, Pati S, et al. Medically underserved girls receive less evaluation for short stature. Pediatrics. 2011; 127(4): 696– 702; doi: 10.1542/peds.2010-1563Investigators from the University of Pennsylvania sought to determine the influence of gender on the evaluation of poor growth in children. A previous report by this group noted that referred girls were shorter than referred boys relative to the population mean and midparental height, and were more likely to have an underlying disease.1In the current study, growth records of 33,476 children aged 6 months to 20 years who attended four urban pediatric primary care offi ces from July 2002 to June 2005 were examined. Criteria for growth-faltering (GF) included: a) height below the 5th percentile, or b) a decrease of 1 to 1.5 standard deviations (SD) on the height Z-score chart. Surrogate markers of socioeconomic status were collected from United States Census data and included median income, employment, and education level. Subjects in these urban practices were predominantly African American (87%) and Medicaid-insured (70%). They lived in census tracts with median household incomes of $24,600; a median of 29% of inhabitants were below the federal poverty line.Nine percent of children met criteria for GF (mean height −1.5 SD) and 1.6% were below −2.25 SD. The racial distribution did not differ significantly between boys and girls. Only 8% of children with GF were referred to a subspecialist. Some children had multiple subspecialty referrals. Subspecialty referral was not significantly associated with gender. Of interest, 6% of GF children were referred to gastroenterology (compared with 1.5% of others; P<.0001) while 2.8% of those with GF were referred to endocrinology (compared with 0.8% of others; P<.005). Race differences were nonsignificant after multivariate analysis.Primary care pediatricians were more likely to order diagnostic tests in children with GF than those without. Thyroid tests were the most frequently obtained endocrine study (9%) and CBC (60%) was the most commonly ordered test. A measure of growth hormone production (GH or IGF-1) was obtained in only 1.4% of tested subjects and was ordered twice as often in short boys compared with short girls. Similarly, chromosome testing was obtained in only 1.4% of girls with GF, and 35% of them were at least 12 years of age. The authors conclude that current practices of diagnostic testing of urban underserved children with growth impairment may lead to underdiagnosis of Turner syndrome and growth hormone deficiency in girls.Dr Heinze has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.The findings of this retrospective case review will come as no surprise to pediatric endocrinologists, and serve to remind our primary care colleagues of the critical importance of both identifying and properly evaluating children with growth impairment. This may be especially true of families of lower income whose members may not consistently raise short stature as a concern with their pediatrician or who have limited access to primary care physicians. The limited laboratory testing performed by providers in this study was particularly striking; IGF-1 measurements, for example, are an essential part of any pediatric growth evaluation as is chromosome analysis in girls with short stature.While concerns have been raised regarding the cost of using growth hormone in some populations of short children,2 this study identifies our shortcomings in the identification and evaluation of short children. In the end, treatment with growth-promoting therapies is reserved for a small percentage of children.The number of children who are small relative to their family and are slow-growing — below the 5th percentile — is considerable and not all of these children will require referral to a pediatric endocrinologist. This report is a reminder of the benefits of detailed tracking of growth velocity and the need for selective comprehensive laboratory investigation.The negative physical and psychosocial consequences of delayed etiologic diagnosis (eg, Turner syndrome) cannot be overemphasized. It is important to note that this study is limited to data from urban clinics whose patients are primarily African American Medicaid recipients. Examination of a more socioeconomically diverse population is the obvious next step.