LAKE BUENA VISTA, FLA. – When it comes to lupus nephritis, the guidelines – and prevailing wisdom – don’t always get it quite right, according to Michelle A. Petri, MD.
During an update at the annual meeting of the Florida Society of Rheumatology, she outlined five key components of lupus nephritis treatment, and the status of the evidence for each.
Antihypertensive therapy isn’t just for hypertension in patients with lupus nephritis – it’s for reducing proteinuria and preventing renal fibrosis, said, professor of medicine and director of the Hopkins Lupus Center at Johns Hopkins University, Baltimore.
“I get a lot of push-back on this,” she added, explaining that other physicians often will stop the treatment as she prescribed it, because they believe it’s unnecessary.
She described a case involving a 33-year-old African American man with blood pressure of 132/86 mm Hg and grade 3+ ankle edema. Laboratory tests were remarkable for hematocrit (33.4%), white blood cell count (3.1), erythrocyte sedimentation rate (67 mm/hr) and urinalysis (2+ protein by dipstick, 3 red cells/high-power field, no casts). Additionally, 24-hour urine protein showed 400 mg of microalbumin, and he had a positive antinuclear antibody test, positive anti–double stranded DNA, and low complement.
“I’m going to argue really strenuously that he has to be on an ACE inhibitor or an ARB [angiotensin receptor blocker],” she said, explaining that even before an immunosuppressant therapy is started, optimizing ACE inhibitor or ARB therapy can reduce proteinuria by 50%.
The “sweet spot” for blood pressure in these patients is between 110 and 129, she said.
“You don’t want it too low, because you might hurt renal perfusion, but you sure don’t want it above 130,” she said.
The problem is that many physicians think 110 or 112 is too low.
“Not for a lupus nephritis patient,” she said. “It’s really where we want to be.”
ACE inhibitors and ARBs are preferable for reaching this goal, she said, noting that calcium channel blockers have been linked with shorter time to renal failure.
Everyone with lupus nephritis should be on hydroxychloroquine, Dr. Petri argued.
“It improves renal outcomes,” she said. “It more than triples the chance that a patient will have a complete renal response.”
Guidelines from the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) are in agreement on this, she said.
Even the renal guidelines for lupus nephritis now include hydroxychloroquine as mandatory, she added, noting that it is not necessary to check glucose-6-phosphate dehydrogenase (G6PD) before starting treatment.
In fact, a recent study showed that only 2 of 11 patients with G6PD deficiency had episodes of hemolysis, and those episodes did not occur during hydroxychloroquine therapy. The authors concluded that the routine measurement of G6PD levels and withholding therapy among African American patients with G6PD deficiency is not supported, she said ().
“Of course, if your patient has renal insufficiency you’re going to have to reduce the dose in half,” she noted.