Frontal bossing and large hands are usually associated with:

Appeared in: DSSSB 6 September 2024

Explanation

Fragile X syndrome (FXS) is a genetic disorder caused by a mutation in the FMR1 gene on the X chromosome.
It is the most common heritable cause of intellectual disability.
Characteristic physical features, which often become more apparent after puberty, include a long face, large ears, a prominent jaw, and joint hyperextensibility.
While not always the most prominent features, frontal bossing and large hands are classically associated with FXS, making it the best fit among the options.

Option B: Patau syndrome (Trisomy 13) is characterized by severe midline defects.
Option C: Edward syndrome (Trisomy 18) has a distinct set of physical markers not mentioned in the stem.
Option D: Down syndrome (Trisomy 21) presents with a different constellation of facial and physical features.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Clinical features of common genetic syndromes as background academic context rather than a clinical decision trigger.
Recognizing dysmorphic features is a key nursing skill for the early identification of potential genetic syndromes, enabling timely referral for genetic counseling and diagnostic testing.
Nurses play a vital role in supporting families of children with genetic disorders, providing education on the condition, managing associated health problems, and connecting them with support services.
What if? If the patient presented with a single palmar crease and a flat facial profile instead, the most likely associated condition would be Down syndrome (Trisomy 21).

How to Approach the Question

First, identify the key clinical features mentioned in the question stem: 'frontal bossing' and 'large hands'.
This is a factual recall question that requires knowledge of the characteristic physical findings of common genetic syndromes.
Systematically evaluate each option against the features in the stem.
Recall that Fragile X syndrome is associated with a long face, large ears, prominent jaw, and large hands.
Contrast this with the classic findings of the other syndromes: Patau (clefting, polydactyly), Edward (clenched hands, prominent occiput), and Down (flat face, single palmar crease).
Conclude that Fragile X syndrome is the only option that aligns with the described features of frontal bossing and large hands.

Concept Tested & Keywords

Q_x80vH303LHwPX-SeTcXR

E6 Kaplan Sadock's Synopsis of Psychiatry-2022 (pp 1-3768 of 3768) p. 275-277

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 428-430

Practise the full DSSSB 6 September 2024

Attempt every question from this paper in a timed mock, then review the full solution for each one.