Evaluation for Clinical Predictors of Positive Temporal Artery Biopsy in Giant Cell Arteritis

Abstract

Infrapopliteal Percutaneous Transluminal Angioplasty Versus Bypass Surgery as First-Line Strategies in Critical Leg Ischemia: A Propensity Score Analysis Soderstrom MI, Arvela EM, Korhonen M et al. Ann Surg 2010;252:765-73.Conclusion: Infrapopliteal percutaneous angioplasty, when feasible, can be an effective first-line strategy achieving similar long-term results as bypass surgery in patients with critical limb ischemia (CLI) when redo procedures are actively used.Summary: Retrospective studies of patient characteristics in endovascular and surgical trials often differ significantly. Propensity score analysis can be used to adjust for important differences between treatment groups. In this study, propensity score analysis was used to compare outcomes in patients who underwent percutaneous transluminal angioplasty (PTA) or bypass surgery of infrapopliteal arteries. The study cohort consisted of 1023 nonrandomized patients treated for CLI, with 262 endovascular and 761 surgical revascularization procedures performed on tibial or pedal arteries. A propensity score was used for stratification and for adjustment in multivariable analysis. Choice of treatment was based on physician preference and treatment feasibility. PTA and bypass surgery achieved similar 5-year limb salvage (75.3% vs 76.0%), similar survival (47.5% vs 43.3%), and amputationfree survival (37.7% vs 32.7%). Rates of freedom from further revascularization were also similar (73.3% vs 74.4%). Freedom from surgical revascularization was higher after bypass surgery (94.3% vs 86.2%, P Ͻ .001). Outcomes were similar with propensity-score matched pairs except for freedom from surgical revascularization, which was higher in the bypass surgery group (91.4% vs 85.3% at 5 years, P ϭ .045). In patients who underwent isolated infrapopliteal revascularization, PTA was associated with better limb salvage (75.5% vs 68.0%, P ϭ .042). Differences in freedom from surgical revascularization were not significant (78.8% vs 85.2%, P ϭ .17). The difference in the limb salvage rate was not maintained in propensity score-matched pairs (P ϭ .12).Comment: Propensity score analysis is an interesting mathematical exercise. However, as pointed out by Dr J. F. Hamming in a discussion after the article, the authors are still comparing "apples with oranges," in that endovascular treatment was reserved for patients with shorter lesions and mostly stenosis and not occlusions. The underlying problem of trying to compare treatment modalities in patients with differing extent of disease still exists. What the paper really demonstrates is that it is possible to be reasonably good at individualizing treatment in patients with CLI. The overall effectiveness of the different treatment modalities in patients with equal burden of disease is not answered by this study.

Calcification of the external carotid arteries and their branches

“…Nevertheless, the definitive diagnosis of whether the calcification occurs within the intima, media or both rests upon the histopathology. Although temporal artery biopsy (TAB) is the standard investigation for giant cell arteritis, 5 there was no longer any pressing clinical indication for TAB in the present case, whose CKD had been successfully treated by renal transplant. The brown tumour had already regressed sufficiently 4 months after the renal transplant (and more than a year after the parathyroidectomy) so that he could wear his lower denture again.…”

Diagnosis and Treatment of Giant Cell Arteritis (Temporal Arteritis) – Past, Current and Future Aspects

“…Fiftynine negative biopsies would have been prevented, but six positive biopsies would have been missed (236). The findings jaw claudication, weight loss, pathological temporal artery enlargement, recent head-ache, and scalp tenderness have all been found to predict a positive biopsy (226,233,236,237). It is tentative to suggest that patients exhibiting none of these clinical features combined with a negative ultrasound should not be subjected to TAB before all other causes of current inflammatory manifestations are ruled out.…”

“…The administration of immunosuppressive therapy such as CS may have little impact on the possibilities of detecting histological vasculitis during the initial phases of therapy. Specimens might show arteritis after 2-4 weeks of CS therapy (225,226,227,228), although the frequency of positive biopsies is slightly reduced for each week of treatment (227,229). Active vasculitis observed in TAB has been demonstrated after as long as 9 years after initiation of CS (230).…”

“…Of major concern is the low number of positive biopsies analyzed by pathological departments. Studies during the years 1976 to 2007 have reported findings of GCA in 13 -43.7 % of TABs (19,226,233,234,235). Consequently, predictive markers for a positive biopsy have long been searched for.…”

Demographic and Laboratory Data May Predict Positive Temporal Artery Biopsy

“…Therefore, it would be beneficial to identify demographic and laboratory data that would increase the likelihood of a positive temporal artery biopsy. There have been several previous studies attempted to determine whether clinical criteria can be used for early identification of GCA [9,10]. However, the criteria identified in these studies were considered to be insufficient for establishing a diagnosis, and TAB is still the gold standard for a definitive diagnosis.…”