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Start free with EleplanPolysyndactyly-cardiac malformation syndrome
ORPHA:2934Malformation syndrome
Also called Bonneau syndrome
What it is
A rare, life-threatening developmental defect during embryogenesis characterized by polysyndactyly of fingers and toes as well as complex congenital heart defects (e.g. atrioventricular septal defects, aortic dextroposition, single ventricle, hypo- or hypertrophy of one side of the heart). Additional features may include dysmorphic traits (large fontanel, high forehead, ptosis, hypertelorism, epicanthus, low-set malformed ears, prominent root of the nose, bulbous nose, anteverted nares, long and smooth philtrum, thin upper lip, micrognathism, hirsutism, single transverse crease) nail hypoplasia, phalange agenesis/hypoplasia, flexion contractures, polysplenia, multiple hepatic/renal cysts, atrophic biliary vesicle, ductal plate malformation and genital anomalies (e.g. micropenis, undescended testes, hypoplastic scrotum). The syndrome is usually fatal in utero or in infancy, but survival cases have been reported.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy, Neonatal
- Inheritance
- Autosomal recessive
- Classified as
- Malformation syndrome
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Common30–79%
9These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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