Updated Clinical Guidelines for Diagnosing Fetal Alcohol Spectrum Disorders

Abstract

The adverse effects of prenatal alcohol exposure constitute a continuum of disabilities (fetal alcohol spectrum disorders [FASD]). In 1996, the Institute of Medicine established diagnostic categories delineating the spectrum but not specifying clinical criteria by which diagnoses could be assigned. In 2005, the authors published practical guidelines operationalizing the Institute of Medicine categories, allowing for standardization of FASD diagnoses in clinical settings. The purpose of the current report is to present updated diagnostic guidelines based on a thorough review of the literature and the authors' combined expertise based on the evaluation of >10 000 children for potential FASD in clinical settings and in epidemiologic studies in conjunction with National Institute on Alcohol Abuse and Alcoholism-funded studies, the Collaborative Initiative on Fetal Alcohol Spectrum Disorders, and the Collaboration on FASD Prevalence. The guidelines were formulated through conference calls and meetings held at National Institute on Alcohol Abuse and Alcoholism offices in Rockville, MD. Specific areas addressed include the following: precise definition of documented prenatal alcohol exposure; neurobehavioral criteria for diagnosis of fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder; revised diagnostic criteria for alcohol-related birth defects; an updated comprehensive research dysmorphology scoring system; and a new lip/philtrum guide for the white population, incorporating a 45-degree view. The guidelines reflect consensus among a large and experienced cadre of FASD investigators in the fields of dysmorphology, epidemiology, neurology, psychology, developmental/behavioral pediatrics, and educational diagnostics. Their improved clarity and specificity will guide clinicians in accurate diagnosis of infants and children prenatally exposed to alcohol.

FIGURE 1

FASD diagnostic algorithm. See text for complete discussion. A positive dysmorphology facial evaluation requires 2 of the 3 cardinal facial features of FASD (short palpebral fissures, smooth philtrum, and this vermilion border of the upper lip). Cutoffs for neuropsychological testing are –1.5 SD. Cutoffs for stature, weight, and head circumference are at the 10th percentile.

FIGURE 2

Typical child with FAS. The 3 cardinal facial features are evident: short palpebral fissures, smooth philtrum, and relatively thin vermilion border of the upper lip. Midface hypoplasia is also apparent.

FIGURE 3

A, Technique for measuring palpebral fissure length. A small plastic ruler is used to measure the distance between the endocanthion (where the eyelids meet medially) and the exocanthion (where the eyelids meet laterally). Subject and examiner should be seated at the same level opposite from one another. Keeping the chin level, the subject is asked to look up, allowing the examiner to bring the ruler as close to the eye as possible (without touching the lashes). The ruler can be rested on the cheek for stability while recording the measurement. B, Note that the ruler is angled slightly to follow the curve of the zygoma. C, The correct length of the palpebral fissure is depicted here as measurement “C.” This highlights the difficulty of 2-dimensional photographic measurement, because “B” is highly variable among individuals, leading to differences in the zygomatic angle (the angle between line segments B and C).

FIGURE 4

Lip/philtrum guide for the white population, incorporating a 45-degree view. This guide was produced by analysis of photographs of >800 white children from school-based studies in the United States.^, Scores are assessed separately for the philtrum and vermilion border; scores of 4 or 5 are compatible with FAS or PFAS.