Mucolipidosis type II (I-cell disease) masquerading as rickets: two case reports and review of literature.

Mucolipidosis type II (ML II) is a rare disease. Its diagnosis is often missed, as it may present with rickets-like picture. ML II and rickets both may have physical findings including fractures, kyphoscoliosis, as well as similar biochemical and radiographic studies. Their similarities often lead to delayed diagnosis and treatment for ML II patients. We describe two cases of ML II, both confirmed by DNA sequencing of the GNPTAB gene and by plasma enzymes assays. The second patient had a much better outcome because of prompt diagnosis and was able to undergo bone marrow transplant as a result. We also review all literature in the English language for cases of ML II presenting with rickets-like pictures.