Macrodystrophia Lipomatosa: A Rare Cause of Bilateral Lower Limb Gigantism

Macrodystrophia lipomatosa (MDL) is a rare congenital overgrowth syndrome characterised by inadvertent proliferation of all the mesenchymal elements resulting in localised gigantism. Herein, we present an eight-month-old female child, who presented to us with a history of gradual enlargement of both lower limbs along with the toes which was noticed by the parents a few days after birth. There was no history of trauma, pain or skin changes. Physical examination revealed unusual hypertrophy of both feet and toes. It was non-tender with no evidence of oedema or bruit over the swelling. X-ray of lower limbs revealed bony hypertrophy and overgrowth of all the bones with increased soft tissue shadow of bilateral foot. On ultrasound evaluation of the lower limbs, there was increased soft tissue in both dorsal and plantar aspect of bilateral foot without any vascular malformation. To characterise the swelling better, magnetic resonance imaging was warranted which revealed accumulation of excessive fat in the subcutaneous tissue without discernible capsule. Fibrous strand within the fat in bilateral feet, both in the plantar and dorsal aspect (more in plantar aspect), was seen. Core tissue biopsy was performed which showed abundant adipose tissue dispersed in mesh-like fibrous tissue and infiltrating the dermal connecting, suggestive of macrodystrophia lipomatosa. Currently, patient is advised for corrective surgery. Clinicians should be aware of these atypical presentations of MDL to differentiate it from other causes of local gigantism like fibrolipohamartoma (FLH) of nerve sheath, lymphangiomatosis, hemangiomatosis, Proteus syndrome, Klippel-Trenaunay syndrome and neurofibromatosis 1 as they differ in management and outcome.