Thalassemia and Moyamoya syndrome: unfurling an intriguing association

Moyamoya angiopathy (MMA) is a rare cerebrovascular disease with progressive bilateral narrowing of intracranial parts of the internal carotid artery and proximal parts of the anterior and middle cerebral artery resulting in recurrent hemodynamic ischemic attacks, strokes and hemorrhages. If associated with other diseases, it is called Moyamoya syndrome (MMS). Until now, MMS has rarely been described with thalassemia.

Of the 75 cases of MMA collected in our Indian center in the last 3 years, 4 new patients with the rare cooccurence of thalassemia and MMS were found. Thalassemia cases were confirmed by hemoglobin electrophoresis and MMA was diagnosed on the basis of MR angiography. Other known secondary causes of MMA were ruled out by relevant investigations. Thirteen previously reported cases of thalassemia and MMA were retrieved by literature search in PubMed and Google Scholar using the keywords "Moyamoya" AND "thalassemia". Subsequently all the data were analyzed and compared by using descriptive statistics.

Analysis of our 4 cases and those 13 found in the literature showed early childhood diagnosis of thalassemia and in most cases later manifestation of MMS in the age of 14.5 + 10.72 years (mean + SD) in our cases and with 10.97 + 6.47 years in previous cases. While 9 out of the former 13 and 3 of our 4 cases showed obvious infarcts in brain imaging, 1 case with HbE-β-thalassemia presented with intracerebral hemorrhage. Hemiplegia/hemiparesis was present among all of our 4 cases, while it was present in 69.23% cases of the previous 13 reports. Neither transfusion dependence nor the history of splenectomy was found to be associated with MMA development.

These four new cases of MMS in thalassemia enlarged our knowledge about MMS in patients with thalassemia. MMS is a relevant complication in patients with thalassemia and early detection is essential to avoid disability.