Pyknoachondrogenesis

What it is

A rare lethal chondrodysplasia characterized by severe generalized osteosclerosis. Main clinical manifestations include large head, palpebral edema, flat nose, low-set ears, hexagon-like mouth, a short neck (hidden by skin folds), a short and wide trunk, a prominent abdomen, and severe micromelic dwarfism with rather normal-length hands and feet. X-rays show marked sclerosis of the facial bones and extremities, and poor ossification elsewhere. It has a lethal outcome, either prenatally or during the early neonatal period. There have been no further descriptions in the literature since 1986.

Key facts

Prevalence

<1 / 1 000 000

Age of onset

Antenatal, 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

These 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