Proposal to decrease the number of negative temporal artery biopsies

Normal inflammatory markers in giant cell arteritis with long-standing cranial and symptomatic large-vessel involvement

We report the case of a 78-year-old woman who presented with cardiovascular risk factors and a history of an atypical transient ischaemic attack. She was referred by her primary care physician to the vascular surgery department at our institution for evaluation of progressive weakness, fatigue, arm claudication and difficulty assessing the blood pressure in her right arm. She was being considered for surgical revascularisation, but a careful history and review of her imaging studies raised suspicion for vasculitis, despite her normal inflammatory markers. She was eventually diagnosed with biopsy-proven giant cell arteritis with diffuse large-vessel involvement. Her symptoms improved with high-dose glucocorticoids.

A Diagnostic Algorithm Based on a Simple Clinical Prediction Rule for the Diagnosis of Cranial Giant Cell Arteritis

Background: Risk stratification based on pre-test probability may improve the diagnostic accuracy of temporal artery high-resolution compression sonography (hrTCS) in the diagnostic workup of cranial giant cell arteritis (cGCA). Methods: A logistic regression model with candidate items was derived from a cohort of patients with suspected cGCA (n = 87). The diagnostic accuracy of the model was tested in the derivation cohort and in an independent validation cohort (n = 114) by receiver operator characteristics (ROC) analysis. The clinical items were composed of a clinical prediction rule, integrated into a stepwise diagnostic algorithm together with C-reactive protein (CRP) values and hrTCS values. Results: The model consisted of four clinical variables (age > 70, headache, jaw claudication, and anterior ischemic optic neuropathy). The diagnostic accuracy of the model for discrimination of patients with and without a final clinical diagnosis of cGCA was excellent in both cohorts (area under the curve (AUC) 0.96 and AUC 0.92, respectively). The diagnostic algorithm improved the positive predictive value of hrCTS substantially. Within the algorithm, 32.8% of patients (derivation cohort) and 49.1% (validation cohort) would not have been tested by hrTCS. None of these patients had a final diagnosis of cGCA. Conclusion: A diagnostic algorithm based on a clinical prediction rule improves the diagnostic accuracy of hrTCS.

Giant Cell Arteritis and COVID-19: Similarities and Discriminators. A Systematic Literature Review

OBJECTIVE

To identify shared and distinct features of giant cell arteritis (GCA) and coronavirus disease 2019(COVID-19) to reduce diagnostic errors that could cause delays in correct treatment.

METHODS

Two systematic literature reviews determined the frequency of clinical features of GCA and COVID-19 in published reports. Frequencies in each disease were summarized using medians and ranges.

RESULTS

Headache was common in GCA but was also observed in COVID-19 (GCA 66%, COVID-19 10%). Jaw claudication or visual loss (43% and 26% in GCA, respectively) generally were not reported in COVID-19. Both diseases featured fatigue (GCA 38%, COVID-19 43%) and elevated inflammatory markers (C-reactive protein [CRP] elevated in 100% of GCA, 66% of COVID-19), but platelet count was elevated in 47% of GCA but only 4% of COVID-19 cases. Cough and fever were commonly reported in COVID-19 and less frequently in GCA (cough, 63% for COVID-19 vs 12% for GCA; fever, 83% for COVID-19 vs 27% for GCA). Gastrointestinal upset was occasionally reported in COVID-19 (8%), rarely in GCA (4%). Lymphopenia was more common in COVID-19 than GCA (53% in COVID-19, 2% in GCA). Alteration of smell and taste have been described in GCA but their frequency is unclear.

CONCLUSION

Overlapping features of GCA and COVID-19 include headache, fever, elevated CRP and cough. Jaw claudication, visual loss, platelet count and lymphocyte count may be more discriminatory. Physicians should be aware of the possibility of diagnostic confusion. We have designed a simple checklist to aid evidence-based evaluation of patients with suspected GCA.

Diagnostic Accuracy of Symptoms, Physical Signs, and Laboratory Tests for Giant Cell Arteritis: A Systematic Review and Meta-analysis

Importance

Current clinical guidelines recommend selecting diagnostic tests for giant cell arteritis (GCA) based on pretest probability that the disease is present, but how pretest probability should be estimated remains unclear.

Objective

To evaluate the diagnostic accuracy of symptoms, physical signs, and laboratory tests for suspected GCA.

Data Sources

PubMed, EMBASE, and the Cochrane Database of Systematic Reviews were searched from November 1940 through April 5, 2020.

Study Selection

Trials and observational studies describing patients with suspected GCA, using an appropriate reference standard for GCA (temporal artery biopsy, imaging test, or clinical diagnosis), and with available data for at least 1 symptom, physical sign, or laboratory test.

Data Extraction and Synthesis

Screening, full text review, quality assessment, and data extraction by 2 investigators. Diagnostic test meta-analysis used a bivariate model.

Main Outcome(s) and Measures

Diagnostic accuracy parameters, including positive and negative likelihood ratios (LRs).

Results

In 68 unique studies (14 037 unique patients with suspected GCA; of 7798 patients with sex reported, 5193 were women [66.6%]), findings associated with a diagnosis of GCA included limb claudication (positive LR, 6.01; 95% CI, 1.38-26.16), jaw claudication (positive LR, 4.90; 95% CI, 3.74-6.41), temporal artery thickening (positive LR, 4.70; 95% CI, 2.65-8.33), temporal artery loss of pulse (positive LR, 3.25; 95% CI, 2.49-4.23), platelet count of greater than 400 × 103/μL (positive LR, 3.75; 95% CI, 2.12-6.64), temporal tenderness (positive LR, 3.14; 95% CI, 1.14-8.65), and erythrocyte sedimentation rate greater than 100 mm/h (positive LR, 3.11; 95% CI, 1.43-6.78). Findings that were associated with absence of GCA included the absence of erythrocyte sedimentation rate of greater than 40 mm/h (negative LR, 0.18; 95% CI, 0.08-0.44), absence of C-reactive protein level of 2.5 mg/dL or more (negative LR, 0.38; 95% CI, 0.25-0.59), and absence of age over 70 years (negative LR, 0.48; 95% CI, 0.27-0.86).

Conclusions and Relevance

This study identifies the clinical and laboratory features that are most informative for a diagnosis of GCA, although no single feature was strong enough to confirm or refute the diagnosis if taken alone. Combinations of these symptoms might help direct further investigation, such as vascular imaging, temporal artery biopsy, or seeking evaluation for alternative diagnoses.

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Zusammenfassung. Wir berichten über einen 58-jährigen Patienten mit seit Monaten bestehender B-Symptomatik, rezidivierenden Fieberschüben begleitet von Kopfschmerzen und erhöhten Entzündungsparametern. In der Erstlinienabklärung ergaben sich keine eindeutigen Hinweise auf eine infektiologische oder rheumatologische Ursache, auffällig war lediglich eine mediastinale und hiläre Lymphadenopathie. Zum Ausschluss eines Malignoms wurde eine PET-CT durchgeführt, in der sich eine FDG-Aufnahme im Bereich der grossen Gefässe zeigte, passend zu einer Riesenzellarteritis. Bei eindeutigem Befund konnte auf einen Temporalarterienbiopsie verzichtet und eine Therapie mit Glukokortikoiden begonnen werden.

Clinical predictors of positive temporal artery biopsy

OBJECTIVE

We investigated the ability of known clinical signs and symptoms, as well as common laboratory tests, to correctly predict a positive temporal artery biopsy.

DESIGN

A prospective cohort study.

PARTICIPANTS

Consecutive patients in a tertiary referral centre undergoing temporal artery biopsy.

METHODS

Clinical information was collected using a predesigned questionnaire. Pathology results and laboratory information were collected from digital patient records.

MAIN OUTCOME MEASURE

The predictive value of clinical signs, symptoms, and laboratory values of a positive temporal artery biopsy.

RESULTS

Over a 3-year period, 259 patients were enrolled and 251 patients were analyzed. Sixty-one patients had a positive biopsy. Clinical features most predictive of a positive biopsy were jaw claudication (positive likelihood ratio [LR+] 2.31) and abnormal temporal artery pulse (LR+ 2.62). Receiver operating characteristic curves generated for erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and platelets values showed an area under curve (AUC) value of 0.71, 0.75, and 0.76, respectively. The initiation of steroids decreased the diagnostic utility of the ESR, CRP, and platelets values (AUC = 0.58, 0.61, and 0.63, respectively).

CONCLUSIONS

A variety of clinical signs and symptoms were observed in patients referred for a temporal artery biopsy. Clinical signs and symptoms were less accurate in predicting a positive biopsy than laboratory tests. No combination of clinical signs and symptoms tested was able to predict giant cell arteritis with the certainty necessary to justify or withhold long-term steroid therapy.

Advances in the diagnosis of large vessel vasculitis

The diagnosis of large-vessel vasculitis has experienced substantial improvement in recent years. While Takayasu arteritis diagnosis relies on imaging, the involvement of epicranial arteries by giant-cell arteritis facilitates histopathological confirmation. When appropriately performed temporal artery biopsy has high sensitivity and specificity. However, an optimal biopsy is not always achievable and, occasionally, the superficial temporal artery may not be involved. Imaging in its various modalities including colour-duplex ultrasonography, computed tomography angiography, magnetic resonance angiography and positron emission tomography, are emerging as important procedures for the diagnosis and assessment of disease extent in large-vessel vasculitis. Recent contributions to the better performance and interpretation of temporal artery biopsies as well as advances in imaging are the focus of the present review.

Prevalence of diabetes mellitus in biopsy-positive giant cell arteritis

BACKGROUND

We tested the hypothesis that patients with diabetes mellitus (DM) develop biopsy-positive giant cell arteritis (GCA) significantly less frequently than nondiabetic patients.

METHODS

We compared the prevalence of DM in patients with positive temporal artery biopsy (TAB) with that in patients with negative TAB via a retrospective study of 215 patients who underwent TAB. Patients were classified as having biopsy-positive GCA if microscopic examination disclosed active or healed arteritis. Patients were classified as having DM if they had a diagnosis of diabetes in their medical history or were taking oral hypoglycemic medications and/or insulin at or before the time of biopsy. In addition, we performed a meta-analysis of 8 previously published articles with a total of 1,401 additional biopsy-proven cases of GCA in patients whose status was recorded as diabetic or nondiabetic.

RESULTS

Of 44 cases with biopsy-positive GCA in our patient cohort, only 4 (9.1%) were diabetic at or before the time of biopsy. Of 171 patients with negative TAB, 61 (35.7%) had DM (P = 0.0006). The prevalence of DM among recorded cases of biopsy-positive GCA ranged from 0% to 13.8% in the 8 studies included in our meta-analysis, with a combined frequency of 89 diabetic patients in a total of 1,401 cases (6.35%).

CONCLUSION

The low frequency of a positive TAB in diabetic GCA suspects should be considered when formulating an index of suspicion in the evaluation of patients with possible GCA. More research is needed to delineate the nature of the interaction between DM and GCA.

Evaluation for clinical predictors of positive temporal artery biopsy in giant cell arteritis

PURPOSE

To examine the clinical predictors of a positive temporal artery biopsy (TAB) among patients suspected of having giant cell arteritis.

PATIENTS AND METHODS

We conducted a retrospective study of all consecutive patients who underwent TAB by a single surgeon (K.L.R.) at the Department of Oral Maxillofacial Surgery from April 30, 2002, to June 29, 2006. The medical records were reviewed for the clinical symptoms, laboratory findings, biopsy results, and final diagnosis. The variables of interest as predictors of positive biopsy findings were analyzed using logistic regression analysis.

RESULTS

During the study period, 82 patients underwent TAB. Histologic evidence of arteritis was present in 22 patients (26.8%). Two (2.4%) were diagnosed with giant cell arteritis clinically but had negative TAB findings. The patients presenting with weight loss or jaw claudication were more likely to have a positive TAB finding (odds ratio 4.50, 95% confidence interval 1.45 to 13.93; and odds ratio 3.71, 95% confidence interval 1.28 to 10.76, respectively). No laboratory findings were predictive of a positive TAB finding. Prednisone use before TAB also was not associated with a decreased likelihood of a positive finding.

CONCLUSIONS

Patients suspected of having giant cell arteritis were more likely to have a positive TAB finding if they presented with weight loss or jaw claudication. In the present series, corticosteroid therapy before biopsy did not affect the rate of positive TAB findings.

[Large vessel vasculitis]

Large vessel vasculitis is characterized by local inflammation of the vessel wall of the aorta and its first and second degree branches. Giant cells are found regularly. The process leads to stenoses and occlusions as well as to aneurysmatic dilatation. Recent progress in vascular imaging (colour Doppler ultrasound, MRI and PET) allows to detect Takayasu arteritis at an earlier stage and to reveal the involvement of larger arteries in temporal arteritis (giant cell arteritis, GCA). With increasing frequency, a subtype of predominantly female and less aged GCA patients without cranial symptoms is noticed in whom obstructions are prevailing in the proximal arm vessels or in the aorta. The latter may be affected exclusively. Initial therapy is based on corticosteroids. In GCA, methotrexate hitherto is the only other immunosuppressive drug that has proved to be helpful. Disease activity has to be controlled both by laboratory parameters and vascular imaging.

Analysis of temporal artery biopsies in an 18-year period at a community hospital

OBJECTIVE

To identify analytical and clinical variables that may improve the effectiveness of temporal artery biopsy (TAB) for the diagnosis of giant cell arteritis (GCA).

MATERIALS AND METHODS

A retrospective study of TABs conducted between 1989 and 2007 at the 450-bed Hospital Parc Taulí, Sabadell. Demographic data, clinical manifestations, analytical data prior to the biopsy and final diagnoses were recorded, including only those cases in which these data were reflected in the clinical history.

RESULTS

In this period, 278 TABs were conducted in 181 women (65.1%) and 97 men (mean age 74 years). Seventy-nine (28.4%) were positive (GCA+) and 199 (71.5%) negative (TAB-). The most frequent final diagnoses in the TAB- group were: polymyalgia rheumatica (PMR) (18.6%), giant cell arteritis plus negative TAB (GCA-) (13.6%), tension headache (7.5%), infection (7.5%), other vasculitis (7.5%), and neoplasm (6.0%). The GCA+ group was compared with the TAB- group, the GCA- group and the PMR group. In the multivariate analysis only headache (RR 3.6), jaw claudication (RR 2.9) and abnormal temporal artery on palpation (RR 2.5) revealed statistical differences between the GCA+ and TAB- groups.

CONCLUSION

One third of the biopsies performed at our centre were positive for GCA. The clinical variables that best predicted a positive TAB in our series were headache, jaw claudication, and abnormal temporal artery on palpation.