A very rare cause of acro-osteolysis: Hajdu-Cheney syndrome.

Acro-osteolysis is not uncommon and occurs in several conditions. Additional clinical and paraclinical findings and sometimes the performance of molecular tests can help to clarify the diagnosis. Here, we report the case of a 36-year-old woman who was referred to our department because of acute pain in the extremity of the left index finger. However, subsequent clinical examination also revealed short digits with pseudo-clubbing related to acro-osteolysis. Furthermore, severe osteoporosis, a moderate dysmorphic face, joint hypermobility, biological variables within normal ranges and her clinical history led us to consider the diagnosis of Hajdu-Cheney syndrome. Molecular analysis confirmed the diagnosis with the identification of a mutation in the NOTCH2 gene. The patient received bisphosphonate therapy, which resulted in some clinical and biological improvement 12 months later.