Evaluation of scrotal pigmentation in infants with spectrometry in addition to physical examination and their correlation with 17-hydroxyprogesterone blood levels

Male infants have particular risk for late diagnosis of congenital adrenal hyperplasia (CAH) since many of them do not show clinical characteristics of ambiguous genitalia that may alert the physician. Due to this fact, many countries have adopted newborn screening programmes for 21-hydroxylase deficiency, by using 17-hydroxyprogesterone (17-OHP) levels on heel stick test. Since Turkey has not yet adopted a newborn screening for CAH, the aim of this study was to evaluate the scrotal melanin density of infants with spectrometry, which is an objective and none-invasive method and to determine the association of spectrometric evaluation with physical examination and blood 17-OHP levels. A total of 40 infants were enrolled to the study, 22 of whom were diagnosed by a physician to have scrotal hyperpigmentation and 18 with normal scrotal pigmentation who were admitted for the evaluation of prolonged jaundice. Age, gestational week, birth weight, maternal age and scrotal pigmentation according to physician were recorded. Scrotal pigmentation was also determined by spectrometry and blood 17-OHP levels were measured by RIA (DIAsource 17OH-RIA-CT Kit, DIAsource ImmunoAssays S.A, Belgium). No statistically significant difference was observed between the groups who were categorized by the physician as having "hyperpigmented" or "normal" scrotal color in terms of maternal age, infant's age, gestational week, birth weight, 17-OHP level or spectrometric values. We observed a strong correlation between 17-OHP levels and spectrometric values in all groups (r:0.857, p<0,001). In conclusion this preliminary study is the first one in the literature which evaluates scrotal pigmentation with an objective spectrometric method, and determines its relation with 17-OHP levels. Further studies are needed to employ this method as a none-invasive, indirect screening test fort he screening of CAH in male infants