Hyponatremic-hypertensive syndrome: think of unilateral renal artery stenosis

Hyponatremic-hypertensive Syndrome in a 19-month-old Boy with Renovascular Hypertension

Hyponatremic-hypertensive syndrome (HHS) is an uncommon disorder rarely seen in children. Herein, we report a 19-month-old boy with HHS. He had severe hypertension, polyuria, polydipsia, vomiting, and seizure at presentation. Laboratory findings revealed hyponatremia, hypokalemia, metabolic alkalosis, proteinuria, hypercalciuria, high levels of renin and aldosterone, and renal artery stenosis. All symptoms resolved after nephrectomy. Clinicians should be aware of this syndrome because prompt recognition can be lifesaving.

A pediatric patient with hyponatremic hypertensive syndrome without persistent hypertension in acute phase: A case report and review of literature

Hyponatremic hypertensive syndrome is characterized by hypertension, hyponatremia, and hypokalemia due to unilateral renal artery stenosis. We herein report a 1-year-old hyponatremic hypertensive syndrome infant without persistent hypertension in the acute phase. On the ninth hospital day, his systolic and diastolic blood pressure increased up to 154-160 and 70-84 mmHg, respectively. Acute gastroenteritis and dehydration might transiently mask his hypertension. By percutaneous transluminal balloon angioplasty for right renal artery, his blood pressure finally normalized without antihypertensive drugs. We reviewed 23 previously reported pediatric patients with hyponatremic hypertensive syndrome under the age of 15 years. Including our patient, there are only three reports on hyponatremic hypertensive syndrome without persistent hypertension in the acute phase. Hyponatremic hypertensive syndrome is curable with proper diagnosis and timely intervention. Therefore, pediatricians should pay attention to the signs and symptoms associated with hyponatremic hypertensive syndrome, even if persistent hypertension was absent in the acute phase.

Nephrotic range proteinuria and metabolic alkalosis in Takayasu arteritis

Nephrotic range proteinuria and metabolic alkalosis are unusual findings in large vessel vasculitis. In this case, renovascular hypertension with unilateral renal artery stenosis in Takayasu arteritis was complicated by nephrotic range proteinuria. Symptoms resolved after angioplasty, although non-nephrotic proteinuria persisted. The renal pathology of Takayasu arteritis included focal glomerulosclerosis.

Unilateral renal artery stenosis presented with hyponatremic-hypertensive syndrome - case report and literature review

Background

Renal artery stenosis is one of the secondary causes of pediatric hypertension. Cases with critical unilateral renal artery stenosis manifesting with the hyponatremic hypertensive syndrome are rare and a comprehensive description of this disorder in the pediatric population is lacking in the literature.

Case presentation

We describe a 4-year-old boy who presented with severe hypertension, profound hyponatremia, hypokalemia, nephrotic range proteinuria, and polyuria. Distinctly, the diagnosis of hyponatremic hypertensive syndrome secondary to unilateral renal artery stenosis was confirmed in light of laboratory and radiographic findings of severe natriuresis, elevated renin, and unilateral small kidney. Two weeks following nephrectomy, there was resolution of hyponatremia, hypokalemia, nephrotic range proteinuria and hypertension.

Conclusions

Findings of hyponatremia, hypokalemia, hypertension, polyuria, and unilateral renal hypoplasia can be attributed to a unifying pathology of unilateral renal artery stenosis.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1246-9) contains supplementary material, which is available to authorized users.

Renovascular hypertension: a case with atypical neurological signs

Secondary hypertension is the most frequent form of hypertension in children. Renovascular disease accounts for 5-10% of all childhood hypertension and should be suspected in the presence of severe hypertension found difficult to manage with medical therapy. Uncontrolled hypertension can lead to severe target organ damage. We describe the case of a 13-month-old baby boy with failure to thrive, recent muscular weakness of the lower extremities and irritability. Hypertension was detected and he was admitted to the paediatric intensive care unit with a refractory hypertensive emergency, despite multiple antihypertensive therapies. Bilateral renal artery stenosis was diagnosed through renal angiography and balloon dilation was performed, leading to lower blood pressure. He is currently withdrawing from antihypertensive medication, and slowly gaining weight and recovering from target organ damage. However, weakness of the lower extremities persists and he has been diagnosed with a neurogenic bladder.

Renal artery stenosis precipitates hyponatremic hypertensive syndrome and posterior reversible leukoencephalopathy

BACKGROUND

Hyponatremic hypertensive syndrome (HHS) is an uncommon disorder usually encountered in the adult population with unilateral renal artery stenosis and is under-recognized in the pediatric population.

CASE DIAGNOSIS/TREATMENT

A 19-month-old male presented with new-onset status epilepticus associated with neurological sequelae, and hypertension to a high of 248/150 mmHg. Lab work revealed significant hyponatremia, elevated peripheral renin activity, and increase in aldosterone and ADH levels. A diagnosis of HHS was made. Initial analysis revealed a high-grade proximal renal artery stenosis by magnetic resonance imaging (MRI) and angiogram. Electroencephalogram and an MRI of the brain demonstrated characteristic abnormalities of the left temporal-parietal regions consistent with posterior reversible leukoencephalopathy syndrome (PRES). The patient responded to right renal artery balloon dilation and stent placement. Since intervention and close blood pressure control with Amlodipine, the patient has been free of seizures and is neurologically intact.

CONCLUSION

We report a case of malignant hypertension in a 19-month-old male secondary to renal artery stenosis with associated HHS and PRES. Prognosis of PRES in children with renal disease is excellent. Prompt intervention may offer near complete resolution of physiologic and symptomatic effects of HHS and PRES due to high-grade renal artery stenosis. This report was written with parental consent for de-identified case presentation and radiographs for the educational benefit of other medical professionals.