692315

research-article2017

CPJXXX10.1177/0009922817692315Clinical PediatricsMigliore et al

Resident Rounds

6-Year-Old With Severe Hypertension

Clinical Pediatrics
2018, Vol. 57(2) 241­–244
© The Author(s) 2017
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https://doi.org/10.1177/0009922817692315
DOI: 10.1177/0009922817692315
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Frank Migliore, DO1, Franca M. Iorember, MD, MPH1,
and Abraham Gedalia, MD1

Case Report
DE is a 6-year-old African American boy with a history
of severe hypertension. His hypertension was initially
diagnosed at 12 days of age, requiring antihypertensive
therapy for a few weeks. It subsequently resolved, and
he was able to come off medications. At 2 years of age,
he presented to an outside hospital with seizures and
postictal right-sided paralysis. His evaluation included
magnetic resonance imaging (MRI) of the brain, which
showed acute infarction of the left cerebral hemisphere
involving portions of the left middle cerebral artery distribution. He was then transferred to Children’s Hospital
of New Orleans for further management. On arrival, his
blood pressure (BP) was 195/132 mm Hg. He was
admitted to the pediatric intensive care unit and started
on a nicardipine drip; BP was eventually controlled, and
he was transitioned to oral antihypertensive medications. His renal function was initially abnormal, but creatinine normalized during the course of his stay. A full
workup included renal imaging, which found the renal
artery stenosis as mentioned below.
Magnetic resonance angiogram (MRA) of the head
showed severe stenosis/occlusion of the right internal
carotid artery, with reconstitution of the supraclinoid portion via the circle of Willis. There was abnormal narrowing of the left internal carotid artery with severe stenosis/
occlusion in the siphon. Furthermore, there was abnormal narrowing of some of the sylvian loops on the right,
with absence of sylvian loops in the area of the infarct.
There was occlusion of the distal portion of the right posterior cerebral artery. MRA of the neck showed diffuse
narrowing and tortuosity of both internal carotid arteries
with loss of signal in the prepetrous segment on the right,
which may be occluded (Figure 1). There was diffuse
narrowing of the proximal right vertebral artery, which
was markedly tortuous. Most of the middle portion of the
left vertebral artery was markedly tortuous, which indicated severe stenosis/occlusion. There was marked tortuosity of the anterior spinal artery. Computed tomography
(CT) of the head showed a left frontal lobe infarct, and
CT angiogram (CTA) of the chest showed marked left
ventricular hypertrophy. CTA of the abdomen showed
focal stenosis of the right upper pole renal artery with
poststenotic aneurysmal dilation and irregularities, and

Figure 1. MRA of the neck showing severe vasculopathy:
There is common origin of the right innominate and left
common carotid artery (bovine arch), diffuse narrowing
and tortuosity of both internal carotid arteries, and diffuse
narrowing and tortuosity of the proximal right vertebral
artery. The middle portion of the left vertebral artery is
markedly tortuous. There is also marked tortuosity of the
anterior spinal artery.

narrowing of the left common femoral artery (Figure 2).
Right and left kidney measurements were 6 and 8 cm,
respectively, indicating right renal hypoplasia. Arterial
and venous duplex ultrasound showed a peak systolic
velocity of the right main renal artery of 165 cm/s and
resistive index of 0.77, and peak systolic velocity of the
left main renal artery of 139 cm/s and resistive index of
0.81, indicating renal artery stenosis.
1

Children’s Hospital and LSU Health Sciences Center, New Orleans,
LA, USA
Corresponding Author:
Abraham Gedalia, Department of Pediatrics, Children’s Hospital and
LSU Health Sciences Center, 200 Henry Clay Ave, New Orleans, LA
70118, USA.
Email: agedal@lsuhsc.edu

242

Clinical Pediatrics 57(2)
which is used to describe the abnormal net-like vessels
at the base of the brain on angiogram.1 Moyamoya disease is a chronic progressive cerebrovascular disease
characterized by bilateral stenosis or occlusion of the
arteries around the circle of Willis, with prominent arterial collateral circulation. The etiology of moyamoya
disease is unknown, but there is growing evidence that
the RNF213 gene on chromosome 17q25.3 is an important susceptibility factor.2 In Japan, the annual incidence
of moyamoya has been reported to be as high as 0.94 per
100 000 population.3 In California, the incidence of
moyamoya was 0.28 per 100 000 in Asians, 0.13 per
100 000 in African Americans, 0.06 per 100 000 in
whites, and 0.03 per 100 000 in Hispanics.4 Moyamoya
disease tends to be progressive.5

Clinical Manifestations
Figure 2. Computed tomography angiogram of the
abdomen showing focal stenosis of the right upper pole renal
artery with poststenotic aneurysmal dilation and right renal
hypoplasia.

A diagnosis of severe vasculopathy was made. A thorough workup was done to determine the cause of his vasculopathy, including a full renal, rheumatological workup
and genetic testing. His hypertension was determined to
be a result of renal artery stenosis in addition to his intracranial pathology. Rheumatological workup was negative. Genetic testing also revealed no underlying mutations
in the SLC2A10 and TGFBR2 genes (responsible for
arterial tortuosity syndrome and familial aortic aneurysm,
respectively).
Over the next several years, he remained severely
hypertensive, needing multiple antihypertensive medications for adequate BP control and intermittent hospital
admissions for severe hypertension. Then, in January 2016,
he was admitted with hypotension, and antihypertensives
were briefly held and restarted. During that hospitalization
he had a repeat CTA of the head, neck, chest, abdomen, and
pelvis that showed stable right internal carotid occlusion
and reconstitution of flow through collaterals and progression of renal artery disease, with involvement of the main
renal arteries as well as several renal branches bilaterally.

Final Diagnosis
Based on the clinical presentation and findings in this
patient, a diagnosis of moyamoya disease was made.

Discussion
Moyamoya is a Japanese word meaning “something
hazy like a puff of cigarette smoke drifting in the air,”

The clinical manifestations one typically associates with
moyamoya disease are largely neurological, including:
transient ischemic attack, ischemic or hemorrhagic
stroke, and seizure. What makes our patient unique is his
renal vessel involvement and hypertension. This is a rare
complication of moyamoya disease, which is also rare by
itself. Studies have shown that the prevalence of renovascular hypertension in moyamoya disease in pediatric
patients is 5% to 8.3%.6-8 Extracranial manifestations of
moyamoya disease had not been really considered until
recently. The first retrospective review of renovascular
hypertension in moyamoya was done in 1997 and found
6 (8.3%) cases of renovascular hypertension among 72
moyamoya disease patients over a span of 8 years from
1987 to 1995.6 Another similar-sized retrospective study
from 2004 looked at 73 patients with moyamoya disease.
Of those 73, 4 (5%) were found to have renal artery stenosis. Two (3%) of those 4 had renovascular hypertension.7 In a larger, more recent retrospective study from
2015, 101 patients with moyamoya were reviewed from
July 2008 to May 2013. Renal artery stenosis was identified in 8 (7.9%) of those patients. Of those 8 patients, 5
(4.9%) had hypertension.8
Our patient also had a hypoplastic right kidney. Such
a finding was first described in 2011 by Ramesh et al,9
who reported on a 14-month-old girl with a similar presentation. Their patient had moyamoya disease with
associated unilateral renal agenesis and external iliac
artery stenosis, suggesting that moyamoya disease may
have been of intrauterine onset. Our patient was first
noted to have neurological symptoms at age 2 years.
However, in light of this evidence and the fact that he
had hypertension just after birth, he may have had subclinical disease as a newborn or even in utero, resulting
in his renal hypoplasia.

Migliore et al

243

Diagnosis

hemorrhage.15 However, most of the reports on progression of disease and prognosis are largely focused on
cerebral disease and come from Asia.
Regarding our patient, at his most recent follow-up
visit, he remained hypertensive and needed 3 antihypertensive medications and a low salt diet. He, however,
continues to do well in school with no signs of cognitive
or neurological deficits.

The diagnosis of moyamoya disease is based on the
characteristic angiographic pattern of bilateral stenoses
affecting the distal internal carotid arteries and proximal
circle of Willis vessels, along with the presence of prominent basal collateral vessels. Diagnostic criteria have
been proposed by a Japanese research committee in
1997 and included 4 major requirements:
1.

2.

3.
4.

stenosis or occlusion at the terminal portion of
the internal carotid artery and at the proximal
portion of the anterior and middle cerebral arteries on magnetic resonance angiography;
abnormal vascular networks in the basal ganglia
on MRA; these networks can also be diagnosed
by the presence of multiple flow voids on brain
MRI;
angiographic findings present bilaterally; cases
with unilateral angiographic findings are considered probable; and
exclusion of the following: arteriosclerosis;
autoimmune disease; brain neoplasm; a history
of cranial irradiation; Down syndrome; head
trauma; neurofibromatosis; meningitis.10

Treatment
The treatment of acute stroke in moyamoya disease is
mainly supportive, aimed at reducing intracranial pressure, improving cerebral blood flow, and controlling seizures.11 However, there is no cure for moyamoya disease.
Antiplatelet agents, such as aspirin, have been used for
secondary stroke prevention in patients who are asymptomatic or only mildly symptomatic. Oral anticoagulants
are generally avoided because of the risk of hemorrhage.12
In symptomatic patients, secondary prevention is largely
surgical revascularization.13 Our patient was a young
African American male. The first similar case of such a
patient of African descent was reported in 2001, in which
a young African-Brazilian moyamoya patient was found
to have resistant renovascular hypertension. He was
treated with balloon angioplasty of the renal artery, which
provided only partial relief of the stenosis. He was then
treated with saphenous bypass from the aorta to the renal
artery that reestablished renal blood flow and ultimately
dropped his BP to where it could be controlled with low
doses of diuretic and a β-blocker.14

Prognosis
Moyamoya tends to be a progressive disease, with
increasing vascular pathology, resulting in cognitive and
neurological decline from repeated ischemic stroke or

Summary
In summary, our patient was a young African American
male who initially presented with hypertension as a neonate, and at the age of 2 years with seizure, stroke, and
diffuse intracranial vasculopathy with difficult to control hypertension secondary to renal artery involvement
and resultant hypoplastic right kidney. His autoimmune
and inflammatory workup were unrevealing. Moyamoya
disease is typically thought of as a disease of patients of
Japanese descent; however, it does occur and is an
important consideration in other races as well. It is also
typically thought of as a disease of the intracranial vasculature. However, cases have been reported of extracranial involvement, particularly the renal vasculature,
with resultant difficult to control hypertension. This is a
rare manifestation of a rare disease in a demographic
that is not routinely thought of when it comes to moyamoya disease. Clinicians should consider this diagnosis
in patients with intracranial vasculopathy associated
with renal artery stenosis when autoimmune or/and
inflammatory conditions are ruled out.
Author Contributions
FMI and AG are following the patient in nephrology & rheumatology clinics, respectively. They also helped in writing the
Discussion. FM the case report and helped in the literature
search and the Discussion.

Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this
article.

Funding
The author(s) received no financial support for the research,
authorship, and/or publication of this article.

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