NEU-LAXOVA SYNDROME

The Neu-Laxova is a rare, lethal congenital abnormality that involves multiple systems, that results in neurogenic akinesia.

• Autosomal recessive inheritance.
• Isolated or part of several syndromes (especially ectodermal dysplasia).
• Pathogenesis.
  It has been suggested that it is a neuroectodermal dysplasia or primary abnormality of the muscles, arteries, nerves and bones.

ULTRASOUND (1-4)

• Marked IUGR (100%) (7).
• Microcephaly (83%).
• Micrognathia.
• Icthyosis.
• Fixed flexion contractures, rocker-bottom feet, syndactyly of fingers and toes.
• Anodontia (absence of tooth buds in the maxilla and mandible).
• Open gaping mouth.
• Prominent wide nasal bridge, slanting forehead.
• Shallow orbits with hypertelorism.
• Joint contractures, syndactyly and club foot may be present.
• Excessive subcutaneous edema (distinctive feature).
• Fatty tissue deposition.
• Agenesis of the corpus callosum, lissencephaly, cerebellar hypoplasia, Dandy-Walker anomaly, aplasia of the optic nerves.
• Scaling of the skin.
• Absent eyelids in some cases.
• Bilateral cryptorchidism.
• Low set / malformed ears.
• Minor less commonly reported features include (7):
1. Eye – cataracts, microphthalmia.
2. Mouth – Eclabion, cleft lip and palate.
3. Musculoskeletal – muscle atrophy, kyphosis, calcifies calvarium.
4. CNS – polymicrogyria, spina bifida, anencephaly.
5. GUT – ambiguous genitalia, curved penis, imperforate urethral orofice.
6. GIT – Malrotation, short umbilical cors, ectodermal dysplasia.

TYPES

Two types are suggested (5):

• Type I - Joint contractures, syndactyly, scaly skin and poorly mineralized bones.
• Type II - Massive swelling of the hands and feet, ichthyosis and hypoplastic digits. Renal agenesis, heart defects and cleft lip may be present.

DIFFERENTIAL DIAGNOSIS

• Other fetal akinesia/hypokinesia disorders.
• Cerebro-oculo-facio-skeletal (COFS) syndrome.
• Lethal multiple pterygium syndrome.
• Pena-Shokeir phenotype.
• Harlequin fetus – lethal condition with icthyosis, eclabion, ectropion and limb contractures similar to NLS, however the absence of severe microcephaly and CNS abnormalities in harlequin fetus may help differentiate the two.

REFERENCES

1. Naveed MCS, Vijaya S. New manifestations of Neu-Laxova syndrome. Am J Med Gen 1990;35:55.
2. Russo R, D'Armiento M, Martinelli P et.al. Neu-Laxova syndrome: pathological, radiological and prenatal findings in a stillborn female. Am J Med Gen 1989;32:136.
3. Gulmezoglu AM, Ekici E. Sonographic diagnosis of Neu-Laxova syndrome. J Clin Ultrasound 1994;22:48-51.
4. Bronshtein M, Blumenfeld I, Cohen I et.al. Fetal ultrasonographic detection of hypodontonia in the Neu_Laxova Syndrome. J Clin Ultrasound 1993;21:648-650.
5. Curry CJR. Letter to the editor: further comments on the Neu-Laxova syndrome. Am J Med Genet 1982;13:441.
6. Shapiro I, Borochowitz Z, Degani S et.al. Neu-Laxova syndrome: Prenatal ultrasonographic diagnosis, clinical and pathological studies, and new manifestations. Am J Med Genet 1992;43:602.
7. Shivarajan MA, Suresh S, Jugadeesh S et.al. Second trimester diagnosis of Neu Laxova syndrome. Prenat Diagn 2003;23:21-24.