Prompted in early 2010 by our surgeon, Dr. Jim Givens, one of our neurologists (Dr. Mark Lencke) asked about temporal artery biopsy diagnoses & findings, post-steroid-therapy. So, we did a QA review of our experience the first quarter of 2010, as follows (it turns out that the value of biopsy pathology post-therapy is to (1) document that an actual arterial segment was sampled, (2) complete treatment response and (3) to detect some other vasculitide that would not be steroid responsive. We never published the below study.
Classical temporal arteritis is among the DDX causes of headache workup, is always associated with a very high ESR, and has a dramatically favorable response to steroid therapy (ESR promptly drops to normal & symptoms promptly disappear). The biopsy portion of a work-up for temporal arteritis, if done, almost invariably follows a course of steroid therapy. The classical histological reaction, when found, is of granulomatous arteritis.
Nearly a dozen cases were performed during this period. As an independent expert reviewer, our Dr. John Carter (career-long, highly expert cardiovascular pathologist) reviewed all of the cases. None of the cases during this period had originally been diagnosed as having any evidence of arteritis; Dr. Carter’s subsequent review was also similarly negative for any evidence of active or prior arteritis.
Of course, no one can know whether all cases of granulomatous arteritis, upon treatment, inevitably will leave residua of the recently previous arteritis or not. A case with diffuse granulomatous pattern in the whole 2.7 cm. segment showed incomplete loss of the elastica (I'd estimate that about 50% of elastic was destroyed in patchy fashion)[L12-4190]. Our standard surgical pathology reference textbook (Rosen, 9th ed. page 2449) referencing a 1981 surgical pathology review) notes, “It is important to emphasize that the [histological] changes are often segmental and that a negative biopsy does not rule out the diagnosis [of temporal arteritis]. In one series, only 60% of patients with clinical evidence of temporal arteritis had positive biopsies but the other 40% (showing arteriosclerosis or atherosclerosis) also responded to steroid therapy.”
At any rate, our long-time standard operating procedure for processing segmental temporal artery biopsies remains the same and consists of dividing the 10-16 mm arterial biopsy into six to eight 2 mm segments, totally agar pre-embedding all segments, and then step-sectioning the total specimen at several levels (and also utilizing the special stain for elastic tissue) in the hopes of detecting both routinely visible and special stain evidence (VVG) of active or residual/previous arteritis.
As of early 2012, the web site author has (1) yet to find a clear-cut altered elastic pattern suggesting prior granulomtous alteration, (2) essentially never gets any clinical info other than "headaches", (3) is never told or can find out in the EMR whether there was prior steroid therapy, and (4) always has great difficulty finding out who the referring primary care provider or neurologist is. A current case (CN12-2) experience suggests that a negative biopsy in the face of a classical presentation and response to steroid therapy is an indication that the patient has excellently responsive temporal arteritis and that relapses, if that has been a problem, might be attenuated with the lowest-dose steroid therapy that can be tolerated.
(posted about Sept. 2010; latest addition 14 April 2012)