Andrew Lawton, M.D.
December 2012 – Volume IX, Number 12
Physicians generally agree on how to initiate corticosteroid therapy in the management of giant cell arteritis. The trickier part of the process is to decide how quickly to taper the medication and get patients off the drug. Espigol-Frigole, et al (Ann Rheum Dis 2012; epublished September 2012), chose to assess the expression of interleukin 17A, a protein known to stimulate inflammation in autoimmune diseases, in the walls of temporal artery biopsy specimens from patients with giant cell arteritis. In all, 57 patients with giant cell arteritis were selected prospectively and followed for a mean of 4.5 years. Key data collected included relapses, the time necessary to achieve a maintenance Prednisone dose of less than 10 mg daily, and the time necessary to wean patients off Prednisone completely. The authors measured interleukin mRNA in temporal artery biopsy specimens from all 57 patients plus 19 controls without giant cell arteritis. The authors found increased interleukin 17A activity to be significantly increased in active patients compared to controls. Patients with higher interleukin levels tended to have fewer relapses and took less time (25 weeks vs 44 weeks) to achieve a maintenance dose of less than 10 mg Prednisone daily. The authors concluded the interleukin 17A activity in temporal artery biopsies can be used to predict the response to Prednisone therapy.
Because of the risk for permanent visual loss, a number of new treatment modalities are under investigation for central retinal vein occlusion. Aggemann, et al (Graefes Arch Clin Esp Ophthalmol 2012; epublished September 2012), compared radial optic neurotomy vs intravitreal triamcinolone as therapies. The study prospectively studied 87 patients who were randomly assigned to one of three groups: neurotomy, a single intravitreal injection of 4 mg Triamcinolone Acetonide, or placebo. 47% of patients treated with neurotomy demonstrated an improvement in visual acuity compared to 10% of placebo-treated individuals and 20% of patients treated with Triamcinolone. These numbers were statistically significant. 35% of patients receiving placebo lost more than three lines in visual acuity compared to 8% in the neurotomy group. The authors concluded that radial optic neurotomy may prove to be a more effective treatment for central retinal vein occlusion than single dose intravitreal Triamcinolone injection.
Establishing the diagnosis of giant cell arteritis may be a tricky business even with multiple blood parameters measured and temporal arteries biopsied. Murchison, et al (Am J Ophthalmol 2012; 154:722-729) sought to evaluate the usefulness of criteria generated by the American College of Rheumatology for the diagnosis of giant cell arteritis in patients with both positive and negative temporal artery biopsies. The authors retrospectively reviewed all 112 patients presenting to their service between October 2001 and May 2006 who had temporal artery biopsies. Key data collected included blood test results, biopsy results, and the progression of visual loss after diagnosis. 9 of the 35 patients with positive temporal artery biopsies wound not have been diagnosed with giant cell arteritis alone using the ACR criteria alone. 16 additional patients met only two criteria and required positive biopsies to establish a diagnosis. 11 of 39 patients with negative biopsies met ACR criteria and would have been diagnosed with giant cell arteritis without a biopsy. Diagnostic agreement between the ACR criteria without biopsy and biopsy alone was only 51.4%. With biopsy added to criteria, the correlation increased to 73%. The authors concluded that ACR criteria are insufficient to diagnose giant cell arteritis and that all patients suspected of having the disease should have temporal artery biopsy performed.
Patient X1 is a man in his mid-30s who developed the sudden onset of difficulty seeing objects past 8 feet from him. The next day anything more than a foot away was blurry. Eventually, anything past three inches was blurred. His vision began to clear two days before my exam.
His medical history was significant for ankle surgery, an appendectomy, pericarditis, a bipolar disorder, and depression. His ocular history was as above. His family history was significant for arthritis, cancer, diabetes, heart disease, kidney disease, hypertension, and systemic lupus. Current medications included Depakote, Wellbutrin, and Topamax. A social history indicated smoking 30 cigarettes daily and social alcohol consumption. He reported no allergies to medications.
At exam, his manifest refraction was -0.25+0.25×110 degrees on his right and -0.75+0.75×90 degrees on his left. Although he was only 20/30 at distance with the above refraction, he was J1+ at near without correction.
What is likely going on here?
Discussion of Case IX12 from December 2012 Newsletter
This patient has Wallenberg’s lateral medullary syndrome. This collection of findings is due to a lesion of the lateral medulla. Understanding the components of the syndrome requires knowledge of the regional anatomy. Key clinical components of this syndrome include ipsilateral decrease in pain and temperature sensation of the face, Horner’s syndrome, ataxia, difficulty speaking, and difficulty swallowing. Patients generally report decreased pain and temperature sensation on the opposite side of the body. Patients may report the sensation of being pulled toward the side of the lesion with associated “corrective” deviation of their eyes when closed. Saccades toward the side of the lesion may overshoot; those away from the lesion come up short. Pursuit may be affected as well. They may have vertigo and nystagmus, usually horizontal. The sense of taste may be altered on the ipsilateral side of the tongue. Hiccups frequently accompany the syndrome.
In older patients, the most likely etiology is occlusion of the ipsilateral vertebral or posterior inferior cerebellar artery. In younger patients, demyelinating disease is a significant possibility. Key anatomical structures involved include the medullary vestibular nuclei, nucleus and spinal tract of cranial nerve V, the ventral spinocerebellar tract, the lateral spinothalamic tract, the nucleus ambiguous, the nucleus of cranial nerve IX, and the sympathetic tract.
Fortunately, as with this patient, the probability of recovery is good. In this instance, MRI was negative indicating neither an infarct nor demyelination.