<Brief
History>
A 34-year-old woman who denied any
systemic disease had suffered from persistent high blood
pressure for a half year. She was quiet well-being before this
event and no abnormality was detected in previous annual
health examinations, except for incidentally found high blood
pressure (SBP was between 140-160 mmHg). Since she had no
typical manifestations such as headache, blurred vision,
dyspnea, chest tightness or epistaxis, she paid no attention
to it. However, the blood pressure was still high several
months later, and she visited the out-patient department (OPD)
for help. She denied any oral contraceptive or glucocorticoid
use, renal disease or abdominal trauma history. Physical
examination showed a woman of 157 cm in height and 60 kg in
weight. Her body temperature was 37.2 o
C, blood pressure 152/86 mmHg, and pulse rate was
102 bpm. A systolic murmur was heard over the cardiac apex and
obvious abdominal bruits were auscultated in the periumbilical
area. The pulses in the four limbs were intact and there's no
blood pressure discrepancy between them. The other
examinations were unremarkable.
<Laboratory and
Image
Study>
1. CBC/DC & coagulation
profiles:
Day after admission |
WBC K/μL |
RBC M/μL |
Hgb g/dL |
Hct % |
MCV fL |
Plt K/μL |
0 |
8.51 |
4.55 |
10.8 |
33.4 |
92.3 |
470 |
5th |
8.43 |
4.71 |
11.0 |
33.5 |
92.2 |
450 | 2. Biochemistry
Day after admission |
BUN mg/dl |
Cre mg/dl |
Na mmol/l |
K mmol/l |
GOT U/l |
T-Bil mg/dl |
Alb g/dL |
0 |
9.3 |
0.7 |
141 |
3.8 |
34 |
1.0 |
4.3 |
5th |
10 |
0.9 |
138 |
4.1 |
33 |
0.9 |
| 3. Urine analysis:
Day after admission |
Appearance |
Sp. gr |
pH |
Protein mg/dL |
Glu g/dL |
Ketones |
O.B |
Urobil EU/dL |
Bil |
0 |
Y;C |
1.02 |
7.0 |
>300 |
- |
- |
- |
0.1 |
- |
5th |
Y;C |
1.02 |
7.0 |
>300 |
- |
- |
- |
0.1 |
- |
Day after admission |
Nitrite |
WBC |
RBC /HPF |
WBC /HPF |
EpithCell /HPF |
Cast /LPF |
Crystal |
Bact |
0 |
- |
- |
0-1 |
0-1 |
0-3 |
- |
- |
- |
|
- |
- |
0-1 |
0 |
3-5 |
- |
- |
- | 4.
Renal echo:
Size |
R't 10.2 cm ; L't 10.9 cm |
Shape |
Bilaterally normal |
Cortical thinkness |
R't: 9 mm; L't: 9 mm (within normal limit) |
Central sinus |
No hydronephrosis |
Solid or cystic lesion |
Nil
|
5. CXR: normal heart size and
clear lung fields.
6. Magnetic
Resonance Imaging and Angiography without/with
Gadolinium-ABDOMEN
- Bilateral renal sizes are intact but
showing the zig-zag appearance. The orifices are intact.
Focal collateral vessels are noted around the right renal
hilum. Fibromuscular dysplasia (FMD) should be excluded. The
pattern could be also dissection, or unknown
etiology.
- No evidence of focal lesions in the
liver, spleen, pancreas, both adrenal and kidneys.
- No evidence of paraaortic LAPs in abdomen; no
ascites.
7. Computer tomography
angiography-Brain: negative for aneurysm
8. Serology
- 24 hours urine VMA: within normal
limit
- Plasma aldosterone/Plasma rennin
activity: high
- Thyroid function: within normal
limit
- Adrenal function: within normal limit and normal diurnal
change
<Course and
Treatment>
Initially, her blood pressure was controlled by max. dose
of Amlodipine and Losartan. Because of the clinical
presentations and MR angiography finding, FMD was highly
suspected. Renal angiography was performed which showed a
bead-like appearance of the right distal renal arteries.
Besides, significant stenosis of the right renal arteries was
also noted. (80% stenosis, Figure A) Then she underwent
percutaneous transluminal angioplasty (PTA) with stenting
smoothly and was discharged and followed up at our OPD. Her
blood pressure improved gradually during the follow-up period
and all drugs for hypertension were withdrawn finally.
<Analysis>
Generally speaking, investigations to rule out the
possibility of secondary hypertension (HTN) are needed in
people who are younger than 30 years or older than 60 years
having hypertension, HTN is refractory to more than 3 drugs
with max. dose control, abdominal bruits and other specific
clinical presentations etc. Five categories should be
considered in diagnosing 2nd HTN: 1. Renal vascular disease 2.
Renal parenchymal disease 3. Endocrinopathy 4. Congential
heart disease 5. Drugs like oral contraceptives,
Erythropoietin, Cocaine, Amphetamine.
Usually, the congenital heart disease
could be diagnosed by pediatrists in patient's early life, but
we should still pay attention to it. In HTN resulting from
renal parenchymal disease, glomerulonephritis (GN) is the main
reason. GN-related 2nd HTN is often associated with
renal dysfunction (high BUN and Creatinine), proteinuria,
hematuria and/or pyuria. Renal imaging study may be normal.
Most of the diagnosis should be made by renal biopsy. In
endocrinopathy, like pheochromocytoma, Cushing's syndrome,
Graves' disease, acromegaly, aldosteronism etc. should also be
considered. However, each disease has its distinct clinical
presentations and could be diagnosed by serology tests.
Besides, she also denied any drug abuse history. Although her
blood pressure was not refractory to drug therapy and not
exceeding 3 drugs, 2nd
HTN still needs to be ruled out in this woman because of her
age of HTN onset. Based on the general classification, this
patient fell into the category of renal vascular disease.
Renal artery stenosis (RAS) is the main constituent of
renal vascular diseases. It can be divided into two main
types: atherosclerotic RAS and FMD. Atherosclerotic RAS
usually occurs in elderly with both renal arteries proximal
parts involvement. However, FMD is an angiopathy that affects
medium-sized arteries predominantly in young women of
childbearing age at distal 2/3 parts of renal artery.
Of patients with identified FMD, renal involvement occurs
in 60-75%, cerebrovascular involvement occurs in 25-30%. The
etiology of FMD is not known and the frequency of FMD in
Taiwan is also unknown. FMD lesions likely predispose the
artery to dissect through weakening of the arterial wall. It
ever hints of a genetic cause of FMD, such as collagen or
elastin mutation, epidemiologic data suggesting familial
transmission are generally weak. It generally follows a benign
course and is frequently an incidental finding. However,
cranial involvement bears worse prognosis because of the
occurrence of dissection and strokes and the coexistence of
saccular aneurysms.
Most patients with FMD are asymptomatic. Others report
nonspecific problems like headache, dizziness, but FMD most
commonly affects the renal arteries and can cause refractory
renovascular hypertension. No serology exam is useful but the
imaging exam like CT angiography, MR angiography. Conventional
angiography c remains the criterion standard to detect FMD and
its associated vascular lesions but it could be postponed when
intervention is needed.
The medical treatment is similar to
general HTN therapy. Because it is usually one side
involvement, the mechanism of 2nd
HTN angioplasty is mainly Angiotensin II dependent HTN.
And Angiotensin II receptor blocker can be considered first.
By performing angioplasty with/without stenting, the success
rate has been reported to exceed 90%. So, in patients with
definite diagnosis of FMD, angioplasty with/without stenting
should be considered first.
<Reference>
- Harrison's principles of internal
medicine 15 edition
- Comprehensive Clinical Nephrology
2nd edition
- NEJM 2004;350(18):1862-1871 4. eMedicine, Fibromuscular
dysplasia. Last Updated: October 6, 2005
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