Temporal arteritis: a decision-analytic approach to temporal artery biopsy

Influence of previous corticosteroid therapy on temporal artery biopsy yield in giant cell arteritis

OBJECTIVE

To determine the impact of prior corticosteroid treatment on temporal artery biopsy (TAB) yield to establish the diagnosis of giant cell arteritis (GCA).

METHODS

Retrospective study of a consecutive cohort of 78 patients clinically diagnosed and managed as GCA, who received corticosteroids before TAB.

RESULTS

Among the 78 patients, TAB was positive in 57 (73%) and negative in 21 (27%). No significant differences in the length of the specimen were found between the positive and negative biopsies. We grouped patients according to treatment duration before TAB. In those with newly diagnosed GCA treated with high-dose steroid therapy, the biopsy results were positive in 78% (35/45) of patients treated for less than 2 weeks, in 65% of those treated for 2 to 4 weeks (13/20), and in 40% of those treated for more than 4 weeks (2/5). We also observed 8 patients that developed GCA on a background of a prior history of polymyalgia rheumatica (PMR); in this group biopsy was positive in 88% of the cases, after a median duration of treatment of 180 +/- 172 days and an average daily dose of 7.1 +/- 1.4 mg/d.

CONCLUSION

The performance of TAB should not delay the prompt institution of steroid therapy on diagnosis of GCA, since the diagnostic yield of TAB seems valuable within 4 weeks of starting high-dose steroid treatment. In patients that developed GCA on a background of a prior history of PMR, a late TAB is also generally informative despite long-term treatment with low doses of corticosteroids.

Effect of prior steroid treatment on temporal artery biopsy findings in giant cell arteritis

AIM

To examine the effect of up to 6 weeks of corticosteroid treatment on the positive temporal artery biopsy rate in giant cell arteritis (GCA).

METHODS

Prospective comparative clinical study of 11 patients meeting the American College of Rheumatology criteria for diagnosis of GCA. Patients underwent temporal artery biopsy within 1 week, at 2-3 weeks, or after 4 weeks of corticosteroid treatment.

RESULTS

Overall, nine of 11 (82%) patients had positive temporal artery biopsies. Six of seven (86%) biopsies performed after 4 or more weeks of steroid treatment were positive.

CONCLUSION

Temporal artery biopsy is useful several weeks after institution of steroids.

Neurologic manifestations of systemic vasculitis

The clinical features, diagnosis, and treatment of polyarteritis nodosa, Kawasaki disease, hypersensitivity angiitides (including drug-related vasculitis, serum sickness, Henoch-Schönlein purpura, hypocomplementemic vasculitis and cryoglobulinemia), Wegner's granulomatosis, temporal arteritis and Takayasu's arteritis are reviewed from a neurological perspective.

Diagnostic testing for headache

A careful and complete headache history supplemented by a neurologic and general physical examination, as appropriate, enables the astute physician to diagnose most headaches correctly without diagnostic testing. When indications are present (see Box 1), some headache patients with a normal physical examination require testing even though the yield may be low. Failure to test may result in misdiagnosis of potentially serious and life-threatening causes of headaches, such as brain tumors, chronic meningitis, SAH, and temporal arteritis.

The significance of perivascular inflammation in the absence of arteritis in temporal artery biopsy specimens

We retrospectively compared 81 temporal artery biopsy specimens demonstrating perivascular inflammation without evidence of temporal arteritis and 76 specimens demonstrating no inflammation. Patients with perivascular inflammation included 43 women (mean age, 71.2 years). Nineteen patients met the 1990 American College of Rheumatology (ACR) criteria for the diagnosis of temporal arteritis. All patients demonstrated chronic perivascular inflammation consisting primarily of lymphocytes. Granulomas were noted in 4 specimens. Internal elastic lamina disruption, intimal fibroplasia, and dystrophic calcification were noted in 86 arteries examined. Fibrosis or scarring of the vessel walls was observed in 10 specimens. Corticosteroid therapy was beneficial to 33 of 56 patients. In patients with no evidence of inflammation (50 women; mean age, 66.6 years), 21 met ACR criteria for temporal arteritis. Histologically, disruption of the elastic lamina was noted in 75 of 81 arteries biopsied, intimal fibroplasia in 66, microcalcifications in 5, and fibrosis or scarring in 5. In this group, 47 patients received corticosteroid therapy; clinical improvement was noted in 28. Patients with chronic perivascular inflammation but no arteritis seem no more likely to have temporal arteritis on clinical grounds than similar patients without inflammation on biopsy.

Temporal artery biopsy: is there any value in examining biopsies at multiple levels?

AIMS

To analyse the cost-effectiveness of three strategies for examining temporal artery biopsies based on data from cases examined over the past 10 years.

METHODS

Of a total of 172 temporal artery biopsies, five were unsuitable for further analysis, 47 had already had levels cut, and 120 had levels cut as part of the study. All the biopsies were examined blind before and after levels. A tree with eventual diagnostic outcomes for different strategies was constructed and economic and sensitivity analyses performed. Welcan units were used to assess technical workload.

RESULTS

Only one of the 132 initially normal cases and two of 14 diagnosed with periarterial lymphocytic infiltration (PALI) revealed giant cell arteritis after examining the tissue at multiple levels. Fifteen cases (8.9%) showed PALI not previously observed. The marginal cost for each extra case of giant cell arteritis detected was 83.5 Welcan units for a strategy of routine levels on all sections, and 21 Welcan units for a strategy of only cutting levels if PALI was present on the initial section. These costs were sensitive to the frequency of giant cell arteritis in cases with PALI and to the relative extra cost of moving from cutting single section to routine levels.

CONCLUSIONS

Routinely examining a temporal artery biopsy at multiple levels does not increase the diagnostic yield of the test, although selective further examination may be indicated in some cases. The significance of PALI is uncertain. The cost-benefit of the different strategies in terms of clinical decision making revolve around the perceived risk inherent in not making a diagnosis of giant cell arteritis.

Temporal arteritis: a clinical approach

OBJECTIVE

To develop a clinical guide to the evaluation of temporal arteritis.

DESIGN

A Medline English-language search of the literature from 1966 to 1998, including more than 300 articles about temporal arteritis, was performed to develop a guide to the evaluation of temporal arteritis.

RESULTS

A user-friendly guide to the evaluation of temporal arteritis was developed based on the following criteria: (1) clinical suspicion, (2) laboratory testing, and (3) temporal artery biopsy.

CONCLUSION

A clinical guide to the evaluation of temporal arteritis may assist clinicians in the care of patients with this condition.

Diagnostic approach to central and peripheral nervous system vasculitis

The diagnosis of vasculitis is first and foremost a clinical one. Correct diagnosis requires a high index of suspicion coupled with knowledge of the manifestations of other disorders that may masquerade as vasculitis. Treatment of vasculitis requires prolonged use of drugs with the potential for serious side effects. Whereas the prompt initiation of definitive treatment is a very high priority, there is also substantial risk of inappropriately treating self-limited and more benign disorders mimicking vasculitis. This has been a particular problem with primary angiitis of the central nervous system. Laboratory studies, particularly tissue biopsy, provide a crucial adjunct to clinical diagnosis.

Decision analysis in surgery

BACKGROUND

The technique of decision analysis is often applied to clinical policy and economic issues in surgery. Because surgeons may be unfamiliar with such work, this article catalogues decision analysis studies in the surgical specialties.

METHODS

We reviewed the medical literature (1966 to 1994) to identify surgical decision analysis studies and to assess trends over time. Each article was categorized according to the type of journal (surgical, other clinical, or technical) in which it was published and content, including surgical specialty, clinical topic, article focus (individual patient decision making, clinical policy, or cost-effectiveness), and primary findings.

RESULTS

Publication rates of surgical decision analysis have increased dramatically over time. Of the 86 total studies only six were published before 1980. In contrast, 44 studies appeared between 1990 and 1994. Although 77% were published in nonsurgical journals, decision analyses have begun to appear more regularly in surgical forums. Studies addressing all of the surgical specialties were found, although more than one half addressed topics in general surgery (34%) or cardiothoracic surgery (22%). The most frequent topics were gallstones (11 articles), head and neck cancer (five articles), coronary artery disease (four articles), and cerebral arteriovenous malformations (four articles). Articles focusing on clinical policy (i.e., those assessing surgical efficacy for broad groups of patients) now account for large majority of published decision analyses.

CONCLUSIONS

The use of decision analysis in surgery is growing steadily. Because decision analysis is being used to influence clinical policy, it is important for surgeons to be aware of these studies and to be able to review them critically.

Diagnostic testing for the evaluation of headaches

Headaches are one of the most common symptoms that neurologists evaluate. Although most are caused by primary disorders, the list differential diagnoses is one of the longest in all of medicine, with over 300 different types and causes. The cause or type of most headaches can be determined by a careful history supplemented by a general and neurologic examination. Reasons for obtaining neuroimaging include medical indications as well as anxiety of patients and families and medico-legal concerns. In the era of managed care, concerns over deselection and negative capitation may dissuade the physician from ordering even a medically indicated scan. The yield of neuroimaging in the evaluation of patients with headache and a normal neurologic examination is quite low. Combining the results of multiple studies performed since 1977 for a total of 3026 scans reveals the overall percentages of various pathologies as: brain tumors, 0.8%; arteriovenous malformations, 0.2%; hydrocephalus, 0.3%; aneurysm, 0.1%; subdural hematoma, 0.2%; and strokes, including chronic ischemic processes, 1.2%. EEG is not useful in the routine evaluation of patients with headache. Similarly, the yield of neuroimaging in the evaluation of migraine is quite low. Combining the results of multiple studies performed since 1976 for a total of 1440 scans of patients with various types of migraine, the overall percentages of various pathologies are: brain tumor, 0.3%; arteriovenous malformation, 0.07%; and saccular aneurysm, 0.07%. WMA have been reported on MRI studies of patients with all types of migraine, with a range from 12% to 46%. The cause of WMA in migraine is not certain. Cerebral atrophy has been variable reported as more frequent and no more frequent in migraineurs compared with controls. The "first or worst" headache has a long list of possible causes and always includes the possibility of acute subarachnoid hemorrhage. Headaches--especially the sentinel type caused by SAH--often are misdiagnosed. The probability of detecting an aneurysmal hemorrhage of CT scans performed at various intervals after the ictus is: day 0.95%; day 3, 74%; 1 week, 50%; 2 weeks, 30%; and 3 weeks, almost nil. The location of a ruptured saccular aneurysm often is suggested by the predominant site of the SAH. The probability of detecting xanthochromia with spectrophotometry in the CSF at various times after a subarachnoid hemorrhage is: 12 hours, 100%; 1 week, 100%; 2 weeks, 100%; 3 weeks, more than 70%; and 4 weeks, more than 40%. The management of thunderclap headaches with normal CT scan and CSF examinations is controversial. Most patients have a benign course but an unruptured saccular aneurysm occasionally may be responsible for the headache. MR angiography may be a reasonable test to obtain instead of a cerebral arteriogram in many of these cases. About 30% to 90% of patients have headaches of various types and causes after mild head injury. Although most headaches are relatively benign, perhaps 1% to 3% of these patients have life-threatening pathology, including subdural and epidural hematomas, that are detected on CT and MRI scans. Headaches caused by subdural hematomas can be nonspecific. When new-onset headaches begin in patients over the age of 50 years, the physician always should consider whether it may be a secondary headache disorder requiring specific diagnostic testing and treatment. Up to 15% of patients 65 years and over who present to neurologists with new-onset headaches may have serious pathology such as stroke, TA, neoplasm, and subdural hematoma. Headaches are the most common symptom of TA, reported by 60% to 90%. The only over the temple. The diagnosis of TA is based on a high index of clinical suspicion that usually but not always is confirmed by laboratory testing. The erythrocyte sedimentation rate can be normal in 10% to 36% of patients with TA. A superficial temporal artery biopsy can give a false-negative result in 5% to 44% of patients.

Decision analysis in the clinical neurosciences: a systematic review of the literature

Clinical decision analysis can be a useful scientific tool for individual patient management, for planning of clinical research and for reaching consensus about clinical problems. We systematically reviewed the decision analytic studies in the clinical neurosciences that were published between 1975 and July 1994. All studies were assessed on aspects of clinical applicability: presence of case and context description, completeness of the analysed strategies from a clinical point of view, extendibility of the analyses to different patient profiles, and up-to-date-ness. Fifty-nine decision analyses of twenty-eight different clinical problems were identified. Twenty-eight analyses were based on the theory of subjective expected utility, twelve on cost-effectiveness analysis. Four studies used ROC analysis, and fifteen were risk-, or risk-benefit analyses. At least six studies could have been improved by more elaborately disclosing the context of the clinical problem that was addressed. In eleven studies, the effect of different, yet plausible assumptions was not explored, and in eighteen studies the reader was not informed how to extend the results of the analysis to patients with (slightly) different clinical characterisitics. All studies had, by nature, the potential to promote insight into the clinical problem and focus the discussion on clinically important aspects, and gave clinically useful advice. We conclude that clinical decision analysis, as an explicit, quantitative approach to uncertainty in decision making in the clinical neurosciences will fulfill a growing need in the near future.

The influence of sectional interval on the reliability of temporal arterial biopsies in polymyalgia rheumatica

Temporal arterial biopsies from 27 patients with a clinical diagnosis of pure polymyalgia rheumatica (PMR) were examined using light microscopy on paraffin and plastic sections. The primary routine examination of the paraffin-embedded parts of the biopsies (biopsy length: 12.7 +/- 4.5 mm, sub-segments: 4.9 +/- 1.2 mm) revealed 4 positive cases, whereas the primary examination of the smaller plastic-embedded parts showed inflammation in 6 cases (biopsy length: 2.7 +/- 1.2 mm, sub-segments: 0.7 +/- 0.3 mm). Serial sectioning with a 50 microns interval of arteries which were negative primarily revealed three new positive cases in the paraffin-embedded material (total length: 174.0 mm), whereas sectioning the plastic-embedded material (total length: 52.8 mm) produced one more positive artery. All the new cases displayed a focal inflammatory process in atrophic, calcified arterial segments. The high yield of positive biopsies in the present material (11 of 27; 40.7%) demonstrates the diagnostic value of temporal arterial biopsy in PMR and the importance of a careful histologic examination. The results also indicate the influence of biopsy length on the yield of positive biopsies. The division of fixed temporal arterial biopsies into approximately 1-mm-long sub-segments before the embedding and the further serial sectioning of those negative biopsies which are atrophic and/or calcified is recommended in cases of pure PMR.

Surgical pathology of cranial arteritis and polymyalgia rheumatica

In both clinical and histological terms cranial arteritis is one of the most distinctive of all vascular disorders. The dense granulomatous inflammatory infiltrates which characterize the acute stages of the disease resemble those of Takayasu's arteritis or granulomatous angiitis of the central nervous system, but the clinicopathological features in patients with positive temporal artery biopsies are diagnostic. Well over a third of patients with classical signs and symptoms of cranial arteritis have negative temporal artery biopsies, and focal involvement of arteries of the head and neck is the probable explanation for this. Pathologists should be aware of the wide spectrum of histological changes that occur in muscular arteries as part of normal ageing and must not interpret these as evidence of healed arteritis. The histological changes of healed arteritis include medial chronic inflammation with ingrowth of new blood vessels, focal medial scarring and a bizarre pattern of intimal fibrosis. Although ultrastructural and immunohistochemical studies have provided some insight into the underlying pathological changes, they have not contributed directly to the diagnosis of cranial arteritis. Between 15 and 55% of patients with polymyalgia rheumatica have positive temporal artery biopsies, but apart from an elevated ESR there are no other laboratory investigations or biopsy procedures that contribute to diagnosis.

Cranial arteritis mimicking odontogenic pain: report of case

A 65-year-old patient treated for pain of apparent odontogenic origin did not respond to appropriate dental treatment. While the signs and symptoms mimicked a dental problem, further diagnostic evaluation determined the "culprit"--cranial arteritis. Proper treatment immediately after diagnosis is advised as the complications of cranial arteritis can include the rapid onset of blindness.