A recent article published in Neurología (English Edition) reported on a patient who suffered a stroke and was later diagnosed with Moyamoya syndrome associated with paroxysmal nocturnal hemoglobinuria (PNH).

The patient was a 41-year-old male who presented with sudden right upper weakness, facial palsy, and dysarthria in the absence of headache or other neurovegetative symptoms. As he was previously hospitalized for approximately 15 days at another medical center, he was no longer a candidate for fibrinolytic therapy.

His past medical history indicated anemia that once required a red blood cell transfusion but was never further investigated.

His brain magnetic resonance angiography showed a subacute ischemic stroke, chronic bilateral ischemic events, and altered blood flow in the middle cerebral arteries. Cerebral angiography indicated multiple steno-occlusive changes and signs of intracranial arteriopathy.

Read more about PNH complications

The hematologic findings supported a diagnosis of Coombs-negative hemolytic anemia. Moreover, his hemoglobin concentration was 6.6 g/dL, his leukocytes were 4080/mm3, and his platelets were 288,000 /mm3. The levels of indirect bilirubin, lactate dehydrogenase, and reticulocyte count were elevated, while his haptoglobin concentration was below standard values. Peripheral blood smear, serum chemistries, and autoimmunity screening tests were normal.

As the researchers excluded immune and microangiopathic causes of hemolysis, they performed flow cytometry/FLAER and found CD59 deficiency in 50% of erythrocytes, CD16 and CD24 deficiency in 88% of neutrophils, CD24 deficiency in 94.5% of eosinophils, and CD14 deficiency in 91% of monocytes.

A diagnosis of classical PNH associated with typical features of Moyamoya syndrome was established and the patient was referred to hematology for ambulatory follow-up. He received immunotherapy with eculizumab. After 3 months, extremity paresis, mild dysarthria, and speech apraxia persisted but there were no new episodes of hemolysis, thromboembolic events, or acute stroke.

“The importance of identifying a hematological disorder as the etiology of stroke lies not only in its impact on the choice of treatment and secondary prevention of acute cerebrovascular disease but also in the opportunity to potentially improve prognosis and prevent complications associated with the underlying condition,” Giraldo Tapias and colleagues wrote.

Read more about PNH comorbidities

“PNH should be taken into account as a potential cause of ischemic stroke, especially in young patients presenting with Coombs-negative hemolytic anemia. Because Moyamoya syndrome is a potential complication of PNH, intracranial vessels should be regularly assessed in these patients. Early recognition of this disease or other hematological disorders that may result in stroke can lead to early initiation of appropriate therapy which can have a positive impact on quality of life and prevent new thrombotic events.”

Although hematological disorders are not usually the cause of cerebrovascular disease, they are associated with cerebral infarcts of unusual etiology more and more frequently.


Giraldo Tapias LM, Arango Guerra P, Lopez Brokate L. Moyamoya syndrome resulting in stroke as a manifestation of paroxysmal nocturnal hemoglobinuriaNeurologia (Engl Ed). Published online May 2023. doi:10.1016/j.nrleng.2022.05.003