RESUMEN
Objective: The objective of this study was to develop ANcam, a novel method for identifying acanthosis nigricans (AN) using a smartphone camera and computer-aided color analysis for noninvasive screening of people with impaired glucose tolerance (IGT). Research Design and Methods: Adult and juvenile participants with or without diagnosed type 2 diabetes were recruited in Trinidad and Tobago. After obtaining informed consent, participants' history, demographics, anthropometrics, and A1C were collected and recorded. Three subject matter experts independently graded pictures of the posterior neck and upper back using the ANcam smartphone application and Burke methods. A correlation matrix investigated 25 color channels for association with hyperpigmentation, and the diagnostic thresholds were determined with a receiver operating characteristic curve analysis. Results: For the 227 participants with captured images and A1C values, the cyan/magenta/yellow/black (CMYK) model color channel CMYK_K was best correlated with IGT at an A1C cutoff of 5.7% (39 mmol/mol) (R = 0.45, P <0.001). With high predictive accuracy (area under the curve = 0.854), the cutoff of 7.67 CMYK_K units was chosen, with a sensitivity of 81.1% and a specificity of 70.3%. ANcam had low interrater variance (F = 1.99, P = 0.137) compared with Burke grading (F = 105.71, P <0.001). ANcam detected hyperpigmentation on the neck at double the self-reported frequency. Elevated BMI was 2.9 (95% CI 1.9-4.3) times more likely, elevated blood pressure was 1.7 (95% CI 1.2-2.4) times more likely, and greater waist-to-hip ratio was 2.3 (95% CI 1.4-3.6) times more likely with AN present. Conclusion: ANcam offers a sensitive, reproducible, and user-friendly IGT screening tool to any smartphone user that performs well with most skin tones and lighting conditions.
RESUMEN
We determined the prevalence of fetal alcohol syndrome (FAS) in a foster care population and evaluated the performance of the FAS Facial Photographic Screening Tool. All children enrolled in a Washington State Foster Care Passport Program were screened for three conditions: (1) the FAS facial phenotype from a photograph, (2) evidence of brain damage with prenatal alcohol exposure from their Health and Education passport, and/or (3) other syndromes identifiable from a facial photograph. Screen-positives received diagnostic evaluations at a FAS Diagnostic and Prevention Network clinic. The prevalence of FAS in this foster care population was 10 to 15/1000, or 10 to 15 times greater than in the general population. The screening tool performed with 100% sensitivity, 99.8% specificity, 85.7% predictive value positive, and 100% predictive value negative. We conclude that the foster care population is a high-risk population for FAS. The screening tool performed with very high accuracy and could be used to track FAS prevalence over time in foster care to accurately assess the effectiveness of primary prevention efforts.