Hypertrichosis lanuginosa congenita (HLC) is a rare disorder that manifests at birth with excessive lanugo hair that covers the entire body surface, with the exception of the palms, soles, and mucous membranes. Most of the reported cases have been of autosomal dominant inheritance, although sporadic cases have also been reported.

Affected patients may have an increase in the hypertrichosis during childhood, or it may actually decrease. Regardless of hair changes, the lanugo characteristic of the hair will be retained even after puberty. 

No abnormalities of other organ systems are clearly associated with the condition, but single cases with coinciding pyloric stenosis, precocious teeth, tetralogy of Fallot, growth and developmental delay, and congenital glaucoma have been reported.