Mineralizing angiopathy presenting with recurrence of basal ganglia stroke following minor head trauma.

Basal ganglia stroke secondary to mineralizing angiopathy of lenticulostriate arteries is a well-recognized clinical entity following minor head trauma in children. Recurrences are uncommon, and the majority of these recurrences occur within a few months of initial insult. We report a 2-year-old boy who developed recurrence of basal ganglia stroke after a latency of 18 months from the time of first unrecognized insult at 6 months of age. The case brings forth the need to recognize the condition of basal ganglia stroke secondary to mineralizing angiopathy considering the risk of recurrence to occur as far as 18 months after the first stroke.

Introduction

Arterial ischemic stroke is an important cause of neurologic morbidity in neonates and children. The consequences include hemiparesis, intellectual disabilities, and epilepsy. Cerebral arteriopathies contribute to nearly half of the arterial ischemic stroke in children.[1] Basal ganglia stroke in infants, following trivial head trauma, is a well-recognized clinical entity secondary to mineralizing angiopathy of lenticulostriate vessels.[234567] It is considered a benign condition with relatively good prognosis. We report a recurrence of basal ganglia stroke in a 2-year-old child after a latency of 18 months following the first insult of minor head injury at 6 months of age.

Case Report

A 2-year-old boy was hospitalized with a sudden onset of decreased movement of the right half of the body. This was preceded by a fall from the bed, 1 hour back. There was no history of fever, loss of consciousness, seizures, or bleeding from any site. Subsequently, he developed intermittent twisting posturing of the right upper and lower limb. Examination revealed reduced muscle power (upper limb 3/5, lower limb 4/5), brisk deep tendon reflexes, and intermittent dystonic posturing in the right upper and lower limb. Rest of the systemic examination was normal. The child had suffered from a similar episode of weakness involving left upper limb and lower limb following fall from bed at 6 months of age that improved over the next few months. He had residual weakness of the left lower limb which was evident while running. There was no significant family history of stroke or any other neurological illness.

His hemoglobin was 8.7 g/dL, and peripheral smear showed microcytic, hypochromic red cells. Review of magnetic resonance imaging (MRI) brain performed at 6 months of age revealed vascular stroke involving the right striatum; computed tomography (CT) brain showed calcification in the same region suggestive of mineralizing angiopathy [Figure 1]. MRI brain done during the present episode suggested an acute infarct involving the left capsuloganglionic region; there was evidence of old infarct and gliosis in the right lentiform nucleus [Figure 2]. Doppler flow of bilateral common carotid arteries and internal carotid arteries, and echocardiography were normal. Antinuclear antibodies were absent. Protein C and protein S levels, factor V Leiden gene mutation, prothrombin gene, and MTHFR gene mutations were within normal range. Serum homocysteine levels were borderline (27.92 μmol/L; normal 5.46-16.20 μmol/L). IgG/IgM antibodies for cytomegalovirus were absent. He was managed symptomatically with muscle relaxant (tizanidine), acetylcholine receptor antagonist (trihexyphenidyl), and aspirin (5 mg/kg/day). There was a marked clinical improvement in neurological weakness with a reduction in dystonia after 6 months.

Figure 1

MRI Brain done at 6 months of age revealed right-sided acute basal ganglia stroke evident as a hyperintense signal on T2 weighted image (a) in the right lentiform nucleus (arrow) with diffusion restriction on DWI (b) and ADC map (c) with normal magnetic resonance angiography (d)

Figure 2

MRI Brain at 2 years of age revealed a fresh infarct in left basal ganglia evident as a hyperintense signal in left putamen (thin arrow) on T2 FLAIR image (a) with diffusion restriction on DWI image (b) with normal magnetic resonance angiography (c). There is gliosis in the right lentiform nucleus (block arrow) evident as a hypointense signal on T2 FLAIR image (a) with CT scan (d) showing hyperdensity (calcification) in the right lentiform nucleus (arrow)

Discussion

This case highlights the recurrence of basal ganglia stroke following an unrecognized post trivial trauma stroke in infancy after a latency of 18 months. Other causes of recurrent vascular stroke including arterial dissection, structural heart disease, and prothrombotic states like protein C, protein S, antithrombin III deficiency, MTHFR gene mutation, and factor V Leiden gene mutation were absent. Two discrete episodes of sudden onset hemiparesis following trivial fall from the bed with neuroimaging evidence of calcification and gliosis in the right lentiform nucleus with a fresh infarct in left basal ganglia prompted us to reach a diagnosis of recurrent basal ganglia stroke secondary to mineralizing angiopathy of lenticulostriate vessels. This case highlights recurrence of this stroke which is otherwise considered a benign condition with low recurrence risk.

Mineralizing angiopathy can be secondary to infection such as cytomegalovirus, echovirus, Epstein–Barr virus, and mycoplasma. Basal ganglia calcification could also result from metabolic cause (hypoparathyroidism, pseudohypoparathyroidism), genetic cause (Fahr disease, Cockayne syndrome, tuberous sclerosis), traumatic (old intracranial bleed), or it could be idiopathic. The index case had a trivial fall from the bed, and it is highly unlikely that this minor head trauma could have resulted in parenchymal or basal ganglia bleed. Instead, head CT is not routinely recommended among children with minor head trauma.[8] Clinical decision rules like Pediatric Emergency Care Applied Research Network (PECARN) can help the clinician to recognize children at low risk to avoid unnecessary exposure to CT scan.[8] Presence of the focal neurological deficit like hemiparesis following trauma is a fair indication for neuroimaging, as in the index case. The other differentials including congenital intrauterine infection and genetic causes are less likely to consider the absence of microcephaly or developmental delay.

Mineralizing angiopathy of lenticulostriate arteries is postulated to be a risk factor for infarction of the basal ganglia after mild closed head injury.[9] The mineralized vessels (arterioles and venules) are highly susceptible to occlusion following minor trauma. Lenticulostriate arteries being end arteries often lack collateral blood supply leading to permanent sequelae when its blood flow gets compromised. Majority of children with this entity have a complete recovery. It has been observed that three-fourth (19 out of 26; 73%) of children with basal ganglia stroke who had a history of trivial trauma had a complete recovery of their hemiparesis with no recurrence till 6 months follow-up.[5] Longitudinal studies have demonstrated smaller size of lacunar infarct with improvement in arterial narrowing at 3 to 6 months follow-up.[310]

Recurrence of basal ganglia stroke secondary to mineralizing angiopathy has been reported in a series in which 5 out of 22 children had a recurrence of stroke in the contralateral side after an interval of 2 to 3 months following the initial insult.[10] In contrast, the index case developed a new infarct on the other side after a range of 18 months. The child had right basal ganglia stroke with calcification at 6 months of age that remained unrecognized followed by a fresh infarct involving left striatum at 2 years of age. Both these clinical events were provoked by a trivial fall from the bed. The sequence of imaging suggests that mineralizing angiopathy involved lenticulostriate vessels of the right side followed by the left side.

Recurrence of this stroke could probably be attributed to unrecognized stroke in infancy and the absence of aspirin prophylaxis. In a previous study, three of five children with a recurrence of post trivial trauma basal ganglia stroke were on aspirin prophylaxis.[10] This is mainly because the mechanism of stroke is believed to be “mechanical” related to shearing of the stiff vessels due to trauma, and aspirin may not necessarily prevent the occlusion. In any case, parents must be educated to exercise domiciliary precautions to avoid repeated head injuries in children.

The present report in conjunction with the previous report emphasizes the recurrence risk of post-trivial head trauma–related mineralizing angiopathy in children. Considering the recurrence of stroke even on aspirin prophylaxis at an earlier report raises a concern of additional contributory risk factors implicated for recurrence in this clinical entity.[10] Longitudinal studies are required to determine the risk factors for recurrence among children with mineralizing angiopathy induced by trivial trauma.

To conclude, this report highlights that basal ganglia stroke following trivial head trauma can recur after a latency of 18 months following initial insult. It is pertinent for the health care professional to recognize this clinical entity among children presenting to emergency services with a positive past history of minor head injury.

Declaration of patient consent

The authors certify that appropriate parental consent was obtained..

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Conflicts of interest

There are no conflicts of interest.