Age- and gender-related factors:
(1) The depressed nasal bridge in BDLS is seen in infants and very young children but is rare in children over 4 years of age.
(2) The classic pattern of facial features may be lost or less apparent in males after puberty (so diagnosis requires review of childhood photographs)
Classic facial features for BDLS:
(1) characteristic "penciled on" eyebrows
(2) anteverted nostrils
(3) long philtrum
(4) thin lips
(5) crescent-shaped, down-turned mouth
The patient with BDLS will have all or most of these findings, while patients who have been misdiagnosed will have none or only 1 of them.
Additional factors that can help identify a patient with BDLS or support the diagnosis:
(1) behavioral problems (autism, disruptive or aggressive behaviors, other)
(2) underdeveloped orbital ridges and zygomatic arches
(3) hypoplastic nipples and hypoplastic umbilicus
A patient tended to be misdiagnosed if s/he showed mental retardation with one or more of the following:
(1) hypertrichosis
(2) synophrys (eyebrows that grow together)
(3) bushy eyebrows
