Hypertension and Symptomatic Hypokalemia

In this post, Dr. Pantelis Sarafidis (PS) discusses a case in AJKD on hypertension and symptomatic hypokalemia in a patient with simultaneous unilateral stenoses of intrarenal arteries and mesangioproliferative glomerulonephritis with Dr. Matthew Sparks, eAJKD web advisory board member.

eAJKD: Can you summarize the case report?

PS: We describe an unusual presentation of a 25-year-old man with hypertension, unprovoked hypokalemia, intrarenal arterial stenoses, and concomitant hepatitis B-associated mesangioproliferative glomerulonephritis. He was originally diagnosed with acute Pyelonephritis, but found to also be hypertensive and chronic active hepatitis B. Although he was promptly investigated and treated for hepatitis B, his outpatient investigations for secondary hypertension were complicated by 2 episodes of muscular weakness from hypokalemia. He had evidence of secondary aldosteronism, and on renal scintigraphy, his left kidney had inhomogeneous uptake consistent with intraparenchymal scarring. His abdominal MRA and MRI were normal.

eAJKD: Can you tell us how the patient’s renal vascular disease was diagnosed despite a negative MRA of the abdomen?

PS: In the absence of diuretics, secondary aldosteronism with hyper-reninemia narrowed the list of potential diagnoses to renovascular hypertension, renoparenchymal disease, and renin-secreting tumor. Although MRA has one main advantage over intra-arterial renal angiography, being relatively noninvasive, the diagnostic yield of MRA is higher for lesions of the main renal arteries. Therefore the MRA failed to identify stenoses involving interlobar arteries. Current recommendations suggest proceeding with conventional angiography in patients with high clinical suspicion of renovascular hypertension despite negative MRA. In our case, the results of renal scintigraphy needed further investigation and the rare possibility of hepatitis B-associated polyarteritis nodosa needed to be excluded. For these reasons, renal angiography was performed which showed stenoses of multiple intrarenal arteries. We believe these were secondary to intraparenchymal scarring from his history of reflux nephropathy as a child.

eAJKD: What makes this case novel?

PS: It is novel for 2 reasons. First, we describe a case of renin oversecretion leading to secondary hypoaldosteronism, hypertension, and hypokalemia that resulted from unilateral intrarenal artery stenoses due to renal scaring. Secondly, this is a case of mesangioproliferative glomerulonephritis concomitant with chronic hepatitis B infection, with full remission under contemporary treatment.

eAJKD: How is his blood pressure, viral load, and proteinuria now?

PS: His blood pressure is well controlled on lisinopril monotherapy. He is on a single agent for his hepatitis B and his viral load is undetectable. Furthermore, he is in full remission of proteinuria.

eAJKD: What is the take home message?

PS: One needs to thoroughly investigate potential causes of secondary hypertension, including differentiating between renovascular and renoparenchymal disease. As was discussed in this case report, patients with glomerular disease can also have other renal diagnoses that have an impact on therapeutic decision making.

To view the entire article please visit AJKD.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s