Role of Thrombocytosis in Diagnosis of Giant Cell Arteritis and Differentiation of arteritic from Non-Arteritic Anterior Ischemic Optic Neuropathy

Utility of biomarkers and temporal artery biopsy length for investigating giant cell arteritis in Western Australia

AIM

To explore demographic characteristics, biopsy length, and blood biomarker performance in an Australian cohort of patients who have undergone temporal artery biopsy (TAB) for giant cell arteritis (GCA).

METHODS

We extracted data on biopsies performed for GCA between January 2016 and December 2020 at public hospitals in Perth. Sensitivity, specificity, and area under the curve (AUC) were calculated for blood results. We evaluated the proportion of biopsies with post-fixation length less than 15 mm and explored several length associations.

RESULTS

We retrospectively reviewed biopsies of 360 patients (65.8% female, mean age 72.1 years). Biopsy-positive patients were older (6.0 years, P < 0.01), and had higher C-reactive protein (CRP) (44.5 mg/L, P < 0.01), erythrocyte sedimentation rate (ESR) (18.9 mm/h, P < 0.01), and platelets (86.8 × 10³ /μL, P < 0.01) compared with biopsy-negative patients. CRP and platelets had the highest AUCs at 0.76 and 0.71, respectively. Sensitivities for CRP and ESR were 96.2% and 91.5%, respectively. Specificities were comparatively low at 41.3% for CRP and 37.4% for ESR. The proportion of biopsies with sub-optimal length was 55.9% and this varied significantly by site (P < 0.01). Smaller sites performed worse, with a sub-optimal biopsy rate of 87% amongst the three smallest sites.

CONCLUSION

ESR and CRP are helpful preliminary investigations, especially in identifying low-risk patients, but their specificity is limited. Smaller centers had a higher proportion of biopsies with sub-optimal length. Considering the importance of biopsy length for TAB diagnostic value, reviewing biopsy data may assist services in developing improvement strategies.

Ischemic Optic Neuropathies: Current Concepts

Ischemic optic neuropathy (ION) is the term ascribed to optic nerve disease that is the result of a transient or permanent interruption of the blood supply to any portion of the optic nerve. Anterior ischemic optic neuropathy (AION) refers to ischemia of the optic nerve head, whereas posterior ischemic optic neuropathy (PION) indicates ischemia of the posterior optic nerve. IONs are primarily classified as arteritic ION and non-arteritic ION. A subset of ION that occurs around the time of surgery is termed peri-operative ION. These phenomena will be discussed as distinct entities.

Evaluation of SIGLEC1 in the diagnosis of suspected systemic lupus erythematosus

OBJECTIVES

To evaluate and compare the diagnostic accuracy of SIGLEC1, a surrogate marker of type I IFN, with established biomarkers in an inception cohort of systemic lupus erythematosus (SLE).

METHODS

SIGLEC1 was analyzed by flow cytometry in 232 patients referred to our institution with suspected SLE between October 2015 and September 2020.

RESULTS

SLE was confirmed in 76 of 232 patients (32.8%) according to the 2019 EULAR/ACR classification criteria and their SIGLEC1 values were significantly higher compared with patients without SLE (p< 0.0001). A sensitivity of 98.7%, a specificity of 82.1%, a negative predictive value (NPV) of 99.2% and a positive predictive value (PPV) of 72.8% were calculated for SIGLEC1. Adjusted to the highest reported prevalence of SLE, the NPV and PPV were > 99.9% and 0.1%, respectively. Using ROC analysis and Delong testing, the area under the curve (AUC) for SIGLEC1 (AUC = 0.95) was significantly higher than for ANA (AUC = 0.88, p= 0.031), C3 (AUC = 0.83, p= 0.001) and C4 (AUC = 0.83, p= 0.002) but not for anti-dsDNA antibodies (AUC = 0.90, p= 0.163).

CONCLUSION

IFN-I pathway activation is detectable in almost all newly diagnosed SLE patients. Thus, a negative test result for SIGLEC1 is powerful to exclude SLE in suspected cases.

Giant cell arteritis: Its ophthalmic manifestations

Giant cell arteritis (GCA) is the most important medical emergency in ophthalmology, because its most dreaded complication is visual loss, which is preventable if these patients are diagnosed early and treated immediately and aggressively. This is a brief review of GCA, its ophthalmic manifestations, and how to diagnose and manage them.

Arteritic anterior ischaemic optic neuropathy: An update

Ischaemic optic neuropathy (ION) is a major cause of blindness. The clinical approach and management is a matter of debate for the treating neurologist and the ophthalmologist. Of the two broad varieties namely the posterior (PION) and anterior ischaemic optic neuropathy (AION), the arteritic variety of the AION (AAION) is usually due to giant cell arteritis. Giant cell arteritis may only present with visual loss in up to 25% of cases. AAION is a neuro-ophthalmic emergency. Early recognition and differentiation from AAION is imperative in order to prevent further devastating visual loss. A literature search was conducted on pubmed using key words as AAION, arteritic anterior ischaemic optic neuropathy, giant cell arteritis (GCA) and articles from the year 2000 till date were included. In any case very few reviews are available on AAION. The literature search on pubmed provided holistic overview about this clinical significant entity and the same is compiled in this review. Moreover the histopathologic features of a temporal artery biopsy have been described with its microscopic images. In any case reviews are mostly available on the Non arteritic variety of AION. This review recapitulates the diagnostic and management protocol of a patient presenting with AAION.

Monocyte to High-Density Lipoprotein Ratio in Patients with Arteritic and Non-Arteritic Anterior Ischaemic Optic Neuropathy

The purpose of this study was to evaluate the monocyte to high-density lipoprotein (HDL) ratio (MHR) in patients with arteritic anterior ischaemic optic neuropathy (A-AION) and non-arteritic anterior ischaemic optic neuropathy (NA-AION). A total of 98 subjects were included in the study. Patients were divided into three groups: 16 patients with A-AION regarded as group one; 41 patients with NA-AION regarded as group two and 41 healthy subjects regarded as the control group. The MHR was calculated in all participants and compared between the patient and control groups. The mean age of subjects with A-AION, NA-AION and the control group were 75.9 ± 8.9 years, 67.1 ± 9.2 years, and 66.6 ± 6.7 years, respectively. Baseline clinical characteristics, such as diabetes mellitus and hypertension, were similar among groups. The mean MHR was significantly higher only in the A-AION group compared with the NA-AION and control group (p < .001), whereas there was no difference between NA-AION group and control group (p = .110). On receiver operating characteristic analysis, the area under the curve was 0.755, and the best cut- off value was 12.2 with a sensitivity of 72% and a specificity of 80%. An elevated MHR ratio is significantly associated with A-AION and MHR might be used to differentiate A-AION from NA-AION.

Temporal Artery Biopsy in the Workup of Giant Cell Arteritis: Diagnostic Considerations in a Veterans Administration Cohort

BACKGROUND

Giant cell arteritis (GCA) is the most common systemic vasculitis in the American population older than 50 years and is a sight-threatening and life-threatening disease. It is definitively diagnosed with a temporal artery biopsy. Although there are many studies focusing on the clinical presentation and laboratory values in diagnosing GCA in the general population, studies focusing on the veteran population are lacking. This is the first study describing the diagnostic features of GCA in the US military veterans.

METHODS

We performed a retrospective chart review in the Veterans Information Systems and Technology Architecture Computerized Patient Record System (CPRS 1.0, Department of Veterans Affairs Health Data Systems). Anatomic pathology reports from temporal artery biopsies (TABs) were collected, as well as the clinical presentation and laboratory values for each case. Frequency, sensitivity, and specificity were calculated for clinical variables, such as new-onset headache and vision changes, including diplopia, ischemic vision loss/optic disc disease, and amaurosis fugax. A logistic regression (LR) prediction model was then developed to compare veteran risk factors with those of the general population.

RESULTS

Of 292 patients, 40 had positive TABs (13.7%). The average age of subjects with positive TABs was 73 ± 8.8 years (mean ± SD). The average erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in patients with positive TABs (69.1 mm/hr and 56.6 mg/L, respectively) were significantly higher than ESR and CRP in patients with negative TABs (50.5 mm/hr, P = 0.0016 and 32.2 mg/L, P = 0.0394, respectively). Mean platelet levels were much higher (317.6 × 10/L) in patients with positive TABs than platelet levels in those with negative TABs (260.6 × 10/L, P = 0.0005). CRP was the most sensitive variable at 83.3%, followed by ESR with a sensitivity of 80% and new-onset headache with a sensitivity of 62.5%. Jaw claudication and polymyalgia rheumatica (PMR) were most specific (81.3% and 89.3%, respectively). Headache was the most common presenting symptom overall (71.6%), followed by vision changes (50.3%), scalp tenderness (25.7%), jaw claudication (20.9%), and PMR-related symptoms (12.7%). The LR prediction model included scalp tenderness, log (CRP), log (platelets), vision changes, and age, with 50% sensitivity and 88.36% specificity. Platelets (odds ratio [OR] = 4.309, P = 0.049), CRP (OR = 1.504, P = 0.022) and scalp tenderness (OR = 3.860, P = 0.016) were statistically significant predictors of a positive TAB in this population.

CONCLUSIONS

Veterans Administration (VA) patients present with symptomatology similar to that of the general population. A positive biopsy was found in female veterans more frequently than in their male counterparts. Platelet count and scalp tenderness were most predictive. Our LR model provided a highly specific method for detecting GCA in the veteran population at this institution, but further studies are needed to determine the generalizability of the model. This retrospective study serves as a basis for future multicenter VA-wide studies to characterize the unique features in this population.

[Giant cell arteritis: Ischemic complications]

GCA ischemic complications occur generally in patients with a yet undiagnosed or uncontrolled disease. When disease control is fair, ischemic complications may be due mostly to atheromatosis. Ophtalmic complications are most frequent and are dominated by anterior ischemic optic neuropathy. Vasculitic strokes occur essentially in the vertebrobasilar arterial territory. Overt vasculitic coronary disease is exceptional. The diagnosis of upper and lower limbs ischemic complications benefit from advances in echography (halo sign) and positron emission tomography imaging. Treatment relies on corticosteroids (initially 1mg/kg prednisone or more, preceded by intravenous methylprednisolone gigadoses if necessary), the control of cardiovascular risk factors and antiplatelet drugs; heparin may be indicated for threatening limbs ischemia.

The Utility of Fundus Fluorescein Angiography in Neuro-Ophthalmology

While its use is still widespread within the medical retina field, fundus fluorescein angiography (FFA) is increasingly falling out of favour in the investigation of neuro-ophthalmological disease, with the introduction of new technologies, particularly optical coherence tomography. FFA does, however, provide useful diagnostic and prognostic information in many neuro-ophthalmological diseases including papilloedema, pseudo-papilloedema, optic neuropathies and central retinal artery occlusion to name a few. We aim to summarise the main FFA findings in each of these conditions and highlight where FFA is of most use in providing complementary information to other modes of investigation.

Full blood count as an ancillary test to support the diagnosis of giant cell arteritis

BACKGROUND

Temporal artery biopsy is considered the investigation of choice to diagnose definitively giant cell arteritis (GCA) in patients with compatible symptoms. However it is invasive and not completely sensitive. Serum markers, particularly erythrocyte sedimentation rate (ESR), can be supportive, but are not definitive in individual cases.

AIMS

To investigate whether indices derived from the full blood count, including neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were associated with a positive biopsy in patients with suspected GCA.

METHODS

The clinical and pathological details of 537 patients undergoing temporal artery biopsy at our institution from 1992 to 2015 were reviewed.

RESULTS

In univariate analysis high platelets (odds ratio (OR) 4.44, P < 0.001), NLR (OR 1.81, P = 0.02), PLR (OR 3.25, P < 0.001), C-reactive protein (CRP) (OR 3.00, P < 0.001), ESR (OR 3.62, P < 0.001) and increased age (OR 1.03, P = 0.006) were strongly associated with a positive biopsy. In multivariate modelling only high platelets (P < 0.001) and ESR (P = 0.049) maintained significance.

CONCLUSIONS

We conclude that the presence of thrombocytosis and high NLR, PLR, ESR and CRP can all be used clinically to support the diagnosis of GCA prior to biopsy. Of particular note, in multivariate modelling the presence of thrombocytosis is a stronger predictor of a positive temporal artery biopsy than ESR. Therefore, careful consideration of the findings in a full blood count can be used to predict the likelihood of a positive temporal artery biopsy in patients with suspected GCA.

Characterization of serological markers of healed/healing arteritis and giant cell arteritis

OBJECTIVE

Temporal artery biopsy (TAB) is the gold standard for confirming the diagnosis of giant cell arteritis (GCA) when positive. However, the clinical significance of healed/healing (HH) arterial injury on TAB is not well understood. The purpose of this study was to evaluate the clinical significance of this finding on TAB by determining its association with seromarkers typically predictive of GCA.

DESIGN

Single-centre, retrospective, investigational cohort study.

PARTICIPANTS

A total of 385 consecutive TABs for clinical suspicion of GCA between January 2009 and January 2016.

METHODS

Elevations in erythrocyte sedimentation rate, C-reactive protein, and platelet count were compared between patients with negative TAB, GCA-positive TAB, and HH arterial injury using statistical trend testing. Odds ratios of seromarker elevations for HH arterial injury versus GCA were calculated.

RESULTS

Seventy-six GCA-positive, 69 HH, and 240 negative TABs were identified. Mantel-Haenszel tests of trend indicated that platelets >400 000/µL (p < 0.01), erythrocyte sedimentation rate ≥50 mm/hr (p < 0.01), and C-reactive protein ≥24.5 mg/L (p < 0.01) occurred with intermediate frequency in the HH TAB group. The odds of HH TAB were 3.6 times greater (95% CI 1.5-8.5) with platelets >400 000/µL.

CONCLUSION

HH arterial injury is a heterogenous group that requires treatment in the appropriate clinical setting. From our study, we found that the HH group is intermediate between GCA-positive and GCA-negative biopsy with respect to serology markers only. Thrombocytosis is an independent predictor of HH TAB. With further studies, this marker may be considered when making treatment decisions. Further studies are required to better understand this entity.

Could Platelet Indices and Neutrophil to Lymphocyte Ratio Be New Biomarkers for Differentiation of Arteritic Anterior Ischemic Neuropathy from Non-Arteritic Type?

The aim of this study was to assess the possible relationship between AAION (arteritic anterior ischemic optic neuropathy) and NAION (non-arteritic anterior ischemic optic neuropathy) with blood platelet parameters and NLR (neutrophil-to-lymphocyte ratio). The medical records of 12 patients with AAION, 33 patients with NAION, and 35 healthy subjects were examined. MPV, PDW, and PCT values showed marked elevation in AAION and NAION groups compared with control group. The mean NLR was statistically significantly higher only in AAION group compared to the NAION and control groups, suggesting that platelet function plays an important role in AIONs and NLR might be used to differentiate AAION from NAION.

Multivariable prediction model for suspected giant cell arteritis: development and validation

Purpose

To develop and validate a diagnostic prediction model for patients with suspected giant cell arteritis (GCA).

Methods

A retrospective review of records of consecutive adult patients undergoing temporal artery biopsy (TABx) for suspected GCA was conducted at seven university centers. The pathologic diagnosis was considered the final diagnosis. The predictor variables were age, gender, new onset headache, clinical temporal artery abnormality, jaw claudication, ischemic vision loss (VL), diplopia, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and platelet level. Multiple imputation was performed for missing data. Logistic regression was used to compare our models with the non-histologic American College of Rheumatology (ACR) GCA classification criteria. Internal validation was performed with 10-fold cross validation and bootstrap techniques. External validation was performed by geographic site.

Results

There were 530 complete TABx records: 397 were negative and 133 positive for GCA. Age, jaw claudication, VL, platelets, and log CRP were statistically significant predictors of positive TABx, whereas ESR, gender, headache, and temporal artery abnormality were not. The parsimonious model had a cross-validated bootstrap area under the receiver operating characteristic curve (AUROC) of 0.810 (95% CI =0.766–0.854), geographic external validation AUROC’s in the range of 0.75–0.85, calibration p_H–L of 0.812, sensitivity of 43.6%, and specificity of 95.2%, which outperformed the ACR criteria.

Conclusion

Our prediction rule with calculator and nomogram aids in the triage of patients with suspected GCA and may decrease the need for TABx in select low-score at-risk subjects. However, misclassification remains a concern.

Ischemic optic neuropathy as a model of neurodegenerative disorder: A review of pathogenic mechanism of axonal degeneration and the role of neuroprotection

Optic neuropathy is a neurodegenerative disease which involves optic nerve injury. It is caused by acute or intermittent insults leading to visual dysfunction. There are number of factors, responsible for optic neuropathy, and the optic nerve axon is affected in all type which causes the loss of retinal ganglion cells. In this review we will highlight various mechanisms involved in the cell loss cascades during axonal degeneration as well as ischemic optic neuropathy. These mechanisms include oxidative stress, excitotoxicity, angiogenesis, neuroinflammation and apoptosis following retinal ischemia. We will also discuss the effect of neuroprotective agents in attenuation of the negative effect of factors involve in the disease occurrence and progression.

"WHICH Headache to Investigate, WHEN, and HOW?"

PREMISE

Headache is a common problem in medical practice. The International Classification of Headache Disorders (ICHD-3 beta)¹ divides all headaches into two broad categories. Most headaches seen in practice belong to the category of primary headaches, where there is no underlying structural cause identifiable. Less than 10% headaches in practice belong to the category of secondary headaches where there is an underlying condition, that can sometimes be ominous and life-threatening.

PROBLEM

Fear of missing a treatable serious secondary headache disorder is the most important reason why we need to investigate headache patients. There is no dilemma in investigating the patient when the clinical presentation is straightforward but when the headache presents differently or with 'red flags,' it can sometimes be quite challenging to order the right investigation and rapidly arrive at the right diagnosis.

POTENTIAL SOLUTIONS

This article looks at some of the elusive headache scenarios and outlines an approach that addresses the issue of 'appropriate' investigation in the headache patient. With advancing technology and increasing expertise, the author feels it is time now to do away with the practice of ordering an exhaustive battery of tests in all headache patients. With experience, clinicians can learn to choose tests judiciously and order specific tests based on a working diagnosis. As the title suggests, knowing 'WHEN to order WHAT test in WHICH headache patient? ' forms the theme of this article.

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.

Neuro-Ophthalmological Emergencies

Neuro-ophthalmological emergencies constitute vision or life-threatening conditions if diagnosis and treatment are not promptly undertaken. Even with immediate therapy, these clinical entities carry a high rate of morbidity. They may present with diplopia, visual loss, and/or anisocoria. Arteritic anterior ischemic optic neuropathy is an ominous condition, which can cause permanent and severe vision loss, stroke, or aortic dissection, requiring immediate steroid therapy. Pituitary apoplexy may go unnoticed if only computed axial tomography is performed. Diseases affecting the cavernous sinus and orbital apex region, such as cavernous sinus thrombosis or mucormycosis, can give rise to simultaneous vision loss and diplopia and, if not treated, may extend to the brain parenchyma causing permanent neurological sequela. An isolated third nerve palsy may be the harbinger of a cerebral aneurysm, carrying a significant risk of mortality. Horner syndrome can be the initial presentation of a carotid dissection, an important cause of stroke in the young adult. The neurohospitalist should be familiar with the workup and management of neuro-ophthalmological emergencies.

The risk of deep venous thrombosis and pulmonary embolism in giant cell arteritis: a general population-based study

IMPORTANCE

Patients with giant cell arteritis (GCA) may have an increased risk of pulmonary embolism (PE), similar to other systemic vasculitidies; however, no relevant population data are available to date.

OBJECTIVE

To evaluate the future risk and time trends of new venous thromboembolism (VTE) in individuals with incident GCA at the general population level.

DESIGN

Observational cohort study.

SETTING

General population of British Columbia.

PARTICIPANTS

909 patients with incident GCA and 9288 age-matched, sex-matched and entry-time-matched control patients without a history of VTE.

MAIN OUTCOME MEASURES

We calculated incidence rate ratios (IRR) overall, and stratified by GCA duration. We calculated HR of PE and deep vein thrombosis (DVT), adjusting for potential VTE risk factors.

RESULTS

Among 909 individuals with GCA (mean age 76 years, 73% women), 18 developed PE and 20 developed DVT. Incidence rates (IR) of VTE, PE and DVT were 13.3, 7.7 and 8.5 per 1000 person-years (PY) in GCA cohort, versus 3.7, 1.9 and 2.2 per 1000 PY in the comparison cohort. The corresponding IRRs (95% CI) for VTE, PE and DVT were 3.58 (2.33 to 5.34), 3.98 (2.22 to 6.81) and 3.82 (2.21 to 6.34) with the highest IRR observed in the first year of GCA diagnosis (7.03, 7.23 and 7.85, respectively). Corresponding fully adjusted HRs (95% CI) were 2.49 (1.45 to 4.30), 2.71 (1.32 to 5.56) and 2.78 (1.39 to 5.54).

CONCLUSIONS AND SIGNIFICANCE

These findings provide general population-based evidence that patients with GCA have an increased risk of VTE, calling for increased vigilance in preventing this serious, but preventable complication, especially within months after GCA diagnosis.

Headache and temporal arteritis: when to suspect and how to manage

Temporal arteritis, also termed giant cell arteritis, is one of the vasculitides affecting large and medium sized cranial arteries, particularly of the carotid tree. Clinical manifestations may vary from the classic constellation of temporal headache in the elderly accompanied by constitutional signs, jaw claudication, and visual symptoms; therefore, a high index of clinical suspicion may be necessary to identify the disorder. Once suspected, immediate treatment is crucial while exploring any number of diagnostic tools to confirm or refute the diagnosis, since morbidity from untreated temporal arteritis can be devastating. At the same time, achieving a definitive diagnosis is paramount, as treatment can be toxic with significant morbidity of its own. Temporal artery biopsy remains the gold standard, but noninvasive diagnostic approaches are being refined. Corticosteroids remain the cornerstone of treatment, but are ineffective for, not tolerated by, or contraindicated in some individuals, necessitating the exploration of alternatives.

Giant cell arteritis: the importance of immediate and appropriate diagnosis and treatment for better prognosis

This article describes the case of a 68-year-old patient suffering from giant cell arteritis (also known as Horton’s arteritis or temporal arteritis). The patient came to our attention due to a large and sudden visual loss caused by the occlusion of major retinal arteries. The patient had neuralgic pain in the face. The next day, for a thorough examination, the patient went to the day hospital with a further worsening of the visual loss which required immediate admission to the ophthalmological ward for hospitalization lasting 10 days. During the observation period it was difficult to make an instant diagnosis due to the absence of clinical signs or diagnostic tests for Horton’s arteritis. Only after the third day of hospitalization, when corticosteroid therapy was undertaken following the appearance of significant systemic symptoms, did the patient begin to show a gradual improvement in overall clinical status. The case highlights the difficulty in making a rapid diagnosis of giant cell arteritis and the efficacy of early steroid therapy in this vascular autoimmune disease that otherwise may result in irreversible functional and debilitating systemic damage.

Treatment of vision loss in giant cell arteritis

OPINION STATEMENT

If giant cell arteritis is suspected as a cause of visual loss, emergent management is necessary. Clinical suspicion should prompt the practitioner to obtain laboratory studies and initiate treatment prior to establishing the diagnosis. The evaluation includes immediate erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complete blood count (CBC). Treatment begins with high-dose intravenous corticosteroids. We recommend intravenous methylprednisolone (250 mg every 6 h) for 3 to 5 days. During that time, a temporal artery biopsy should be performed for pathologic diagnosis. We also begin daily adjunctive aspirin orally. After the initial bolus of intravenous corticosteroids, therapy transitions to oral prednisone administered at 1 mg/kg per day until the activity of the disease process attenuates, as demonstrated by improvement in systemic symptoms and normalization of both ESR and CRP. This change usually occurs in the first 3 to 4 weeks. The patient should be followed closely, with therapy tapered as guided by systemic symptoms, ESR, and CRP. To maximize the use of remaining vision, appropriate patients should be referred to specialists for help with low-vision therapies, assistive devices, and precautions to protect the better-seeing eye.

Management of ischemic optic neuropathies

Ischemic optic neuropathies (IONs) consist primarily of two types: anterior ischemic optic neuropathy (AION) and posterior ischemic optic neuropathy (PION). AION comprises arteritic AION (A-AION: due to giant cell arteritis) and non-arteritic AION (NA-AION: due to other causes). PION consists of arteritic PION (A-PION: due to giant cell arteritis), non-arteritic PION (NA-PION: due to other causes), and surgical PION (a complication of several systemic surgical procedures). These five types of ION are distinct clinical entities etiologically, pathogenetically, clinically and from the management point of view. In the management of AION, the first crucial step with patients aged 50 and over is to identify immediately whether it is arteritic or not because A-AION is an ophthalmic emergency and requires urgent treatment with high-dose steroid therapy to prevent any further visual loss in one or both eyes. Patients with NA-AION, when treated with systemic corticosteroid therapy within first 2 weeks of onset, had significantly better visual outcome than untreated ones. Systemic risk factors, particularly nocturnal arterial hypotension, play major roles in the development of NA-AION; management of them is essential in its prevention and management. NA-PION patients, when treated with high-dose systemic steroid therapy during the very early stages of the disease, showed significant improvement in visual acuity and visual fields, compared to untreated eyes. A-PION, like A-AION, requires urgent treatment with high-dose steroid therapy to prevent any further visual loss in one or both eyes. There is no satisfactory treatment for surgical PION, except to take prophylactic measures to prevent its development.

Giant cell arteritis: laboratory predictors of a positive temporal artery biopsy

PURPOSE

To identify laboratory predictors of a positive temporal artery biopsy.

DESIGN

Cross-sectional study using retrospective electronic data base review.

PARTICIPANTS

There were 3001 patients who had a temporal artery biopsy.

METHODS

The electronic database of a large health maintenance organization was searched for all patients who had a temporal artery biopsy performed from 1997 to 2006.

MAIN OUTCOME MEASURES

Odds ratios for erythrocyte sedimentation rate, C-reactive protein (CRP), and platelet count values associated with a positive temporal artery biopsy.

RESULTS

Four hundred fifty-nine cases of biopsy-proven giant cell arteritis were identified. The odds of a positive biopsy were 1.5 times greater with an erythrocyte sedimentation rate of 47 to 107 mm/hr, 5.3 times greater with a CRP >2.45 mg/dL, and 4.2 times greater with platelets >400,000/μL.

CONCLUSIONS

In this largest population-based giant cell arteritis study in the United States to date, we reaffirm Hayreh's finding of the significance of a CRP level >2.45 mg/dL in predicting a positive biopsy. Our findings support the literature suggesting that CRP and thrombocytosis may be stronger predictors of positive biopsy than erythrocyte sedimentation rate.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Diagnosis and management of giant cell arteritis: a review

PURPOSE OF REVIEW

This article aims to provide a review of giant cell arteritis (GCA) clinical features, differential diagnosis, treatment options, and recent literature.

RECENT FINDINGS

GCA, first described by Horton et al., is a systemic immune-mediated vasculitis affecting medium-sized and large-sized arteries. Characteristic findings include headache, jaw claudication, visual loss, and constitutional symptoms (malaise, fever, weight loss, loss of appetite). Localized GCA symptoms are the end-result of vascular insufficiency and tissue ischemia. Temporal artery biopsy (TAB) remains the gold standard for diagnosis. Additional diagnostic tests include blood tests (erythrocyte sedimentation rate, ESR; C-reactive protein, CRP; platelets) and imaging modalities (ultrasound of the arteries; fluorescein angiography, FA; MRI; and positron emission tomography, PET). The mainstay of management includes high-dose corticosteroids, and additional cytotoxic drugs, antitumor necrosis factor monoclonal antibody, and antiplatelet aggregation therapy may be used. The goal of treatment is to prevent ischemic damage and halt progression of visual loss in the affected eye and prevent involvement of the fellow eye.

SUMMARY

Further research is warranted concerning the immunogenetics of GCA. Further treatment trials are also needed to develop more specific and sensitive diagnostic tests and new corticosteroid-sparing treatment modalities.

[Clinical and serological findings of giant-cell arteritis]

Giant cell arteritis (GCA) frequently appears as cranial arteritis (eg. temporal arteritis) with headache, pain on chewing and visual disturbances. In addition, extracranial manifestations are often observed leading to aneurysmatic dilatations and dissections of the aorta as well as stenoses of large thoracic, abdominal or limb arteries. The vascular signs are accompanied by general disease symptoms, e.g. malaise, elevated temperatures, weight loss and depression. Polymyalgia rheumatica (PMR) is the most frequent rheumatic manifestation of GCA but also occurs independently from GCA. The structural correlate for the PMR symptoms is first and foremost extra-articular inflammation (tenosynovitis, bursitis) of large joints and the vertebral column (interspinal bursitis). In addition, vasculitis of large arteries in PMR must be considered particularly in the presence of high inflammatory activity. While specific laboratory markers for GCA and PMR are lacking elevated values for the erythrocyte sedimentation rate and C-reactive protein are present in almost all patients at disease onset. Besides the clinical evaluation, the serological acute phase reaction represents the main parameter for the course during therapy of this relatively frequent disease in elderly people.

Ischemic optic neuropathies

Anterior ischemic optic neuropathy (AION) is the most common cause of acute optic neuropathy after age 50, but may also occur in younger patients. The diagnosis is clinical and includes painless visual loss associated with a relative afferent pupillary defect and disc edema. In almost all cases, there is an underlying crowded optic nerve with a small cup-to-disc ratio. The visual prognosis is usually poor, although up to 43% of patients may improve over time. The fellow eye is involved in up to 15% of patients within 5 years, but the risk of recurrence in the same eye is less than 5%. There is no treatment for acute nonarteritic AION but it is essential to evaluate these patients for underlying treatable atheromatous vascular risk factors. A coagulation workup should also be considered in younger patients. It is essential to rule out giant cell arteritis in all patients over the age of 50 with ischemic optic neuropathies. Posterior ischemic neuropathy (in which the optic nerve is normal acutely) is rare and should be considered a diagnosis of exclusion.

High-sensitivity C-reactive protein measurements in patients with non-arteritic anterior ischaemic optic neuropathy: a clue to the presence of a microinflammatory response

PURPOSE

To explore the possibility that individuals with non-arteritic anterior ischaemic optic neuropathy (NA-AION) harbour a heightened microinflammatory response compared to carefully matched controls.

METHODS

Diagnosis and follow-up were performed by a senior neuro-ophthalmologist (A.K.). The inflammatory biomarkers included white blood cell count, Westergren erythrocyte sedimentation rate (ESR), quantitative fibrinogen as well as high-sensitivity C-reactive protein (hs-CRP). The values of the inflammatory biomarkers of four and five matched controls were compared to patients with NA-AION.

RESULTS

We examined 33 NA-AION patients and 151 controls matched for age, gender, body mass index, oral temperature, smoking status and atherothrombotic risk factors. A significantly elevated concentration was noted for hs-CRP (P = 0.021): 3.3 mg/l for NA-AION patients and 2.1 mg/l for controls. Accelerated ESR (18.8 versus 13.5 mm/hr, P = 0.025) was noted in the NA-AION patients.

CONCLUSION

Following appropriate matching to apparently healthy controls, patients with NA-AION presented a microinflammatory response, revealed by the presence of increased hs-CRP concentrations and accelerated ESR. The finding, if confirmed in future studies, might shed more light on the eventual pathophysiological processes involved in the disease and pave the way for new therapeutic approaches.

Giant cell arteritis: an updated review

Giant cell arteritis (GCA) is the most common primary vasculitis of adults. The incidence of this disease is practically nil in the population under the age of 50 years, then rises dramatically with each passing decade. The median age of onset of the disease is about 75 years. As the ageing population expands, it is increasingly important for ophthalmologists to be familiar with GCA and its various manifestations, ophthalmic and non-ophthalmic. A heightened awareness of this condition can avoid delays in diagnosis and treatment. It is well known that prompt initiation of steroids remains the most effective means for preventing potentially devastating ischaemic complications. This review summarizes the current concepts regarding the immunopathogenetic pathways that lead to arteritis and the major phenotypic subtypes of GCA with emphasis on large vessel vasculitis, novel modalities for disease detection and investigative trials using alternative, non-steroid therapies.

C-reactive protein levels do not correlate with retinal artery occlusion but with atherosclerosis

PURPOSE

To determine C-reactive protein (CRP) levels in acute retinal artery occlusion (RAO) and their association with atherosclerotic risk factors.

METHODS

CRP levels in 16 patients with RAO were compared with levels in 16 age-matched controls at risk of atherosclerosis and 16 young volunteers. Repeated CRP testing was performed 6 years later.

RESULTS

Elevated CRP levels (>3 mg/l) and risk factors for atherosclerosis were detected in seven patients in the study group (44%) and nine at-risk controls (56%). On follow-up, CRP levels were reduced in all seven retested patients. Six patients died of vascular events within 5 years, of whom four had high CRP levels during RAO.

CONCLUSIONS

CRP level correlates with atherosclerosis but it is not significantly elevated in patients with RAO.

Antiplatelet and anticoagulant therapy in patients with giant cell arteritis

OBJECTIVE

Vision loss and cerebrovascular accidents often complicate giant cell arteritis (GCA). Antiplatelet and anticoagulant therapy reduce the risk of stroke in other populations. We sought to determine whether antiplatelet or anticoagulant therapy reduces ischemic complications in patients with GCA.

METHODS

A retrospective chart review for patients with GCA was conducted. Included patients fulfilled modified 1990 American College of Rheumatology criteria for GCA. Collected information included demographic data, dates of antiplatelet or anticoagulant use, vision loss or stroke, and presence of bleeding complications and cerebrovascular risk factors.

RESULTS

A total of 143 patients were included with a mean followup period of 4 years. The cohort included 109 women (76%) and 34 men (24%) with a mean age of 71.8 years. A total of 104 patients (73%) had a biopsy-proven diagnosis. Eighty-six patients (60.1%) had received long-term antiplatelet or anticoagulant therapy, including 18 (12.6%) who did not start therapy until after an ischemic event had occurred. Antiplatelet agents or anticoagulants were not used in 57 patients (39.9%). Overall, 11 of 68 patients (16.2%) had an ischemic event while receiving antiplatelet or anticoagulant therapy, compared with 36 of 75 patients (48.0%) not receiving such therapy (P < 0.0005). Univariate analysis failed to show a statistical difference between groups in regard to cerebrovascular risk factors, age, sex, or biopsy-proven diagnosis. Bleeding complications occurred in 2 patients receiving aspirin, 1 patient receiving warfarin, and 5 patients who did not receive anticoagulant or antiplatelet therapy.

CONCLUSION

Antiplatelet or anticoagulant therapy may reduce the risk of ischemic events in patients with GCA. An increased risk of bleeding complications was not observed.

Prevalence of a Normal C-Reactive Protein with an Elevated Erythrocyte Sedimentation Rate in Biopsy-Proven Giant Cell Arteritis

OBJECTIVE

The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are laboratory tests that have been said to have a strong correlation with a positive temporal artery biopsy in patients with suspected giant cell arteritis (GCA). Published reports suggest that the CRP is a more sensitive diagnostic indicator of GCA and can be elevated when the ESR is normal. It is also clear that the CRP and ESR can both be normal or both be elevated in patients with biopsy-proven GCA and that the CRP can be elevated when the ESR is normal. The purpose of this study was to ascertain if the CRP can be normal when the ESR is elevated in biopsy-proven GCA.

DESIGN

Retrospective, longitudinal, comparative study.

PARTICIPANTS

One hundred nineteen patients from 6 major tertiary-care university-affiliated medical centers.

METHODS

The charts from 119 patients with temporal artery biopsies positive for GCA were reviewed for age, gender, pretreatment ESR, and pretreatment CRP.

MAIN OUTCOME MEASURES

The ESR in millimeters per hour Westergren was graded as normal or abnormal based on 2 validated formulas. The CRP was graded as normal or abnormal based on established criteria set forth in the literature as well as at The Johns Hopkins Hematology laboratory.

RESULTS

In this study, the ESR had a sensitivity of 76% to 86%, depending on which of 2 formulas were used, whereas an elevated CRP had a sensitivity of 97.5%. The sensitivity of the ESR and CRP together was 99%. Only 1 of the 119 patients (0.8%) presented with a normal ESR and normal CRP (double false negative); 2 patients (1.7%) had a normal CRP despite an elevated ESR according to both formulas.

CONCLUSION

Although most patients with GCA have both an elevated ESR and CRP, there can be nonconcordance of the 2 blood tests. Although such nonconcordance is most often a normal ESR but an elevated CRP, the finding of an elevated ESR and a normal CRP also is consistent with GCA. The use of both tests provides a slightly greater sensitivity for the diagnosis of GCA than the use of either test alone.

Balloon angioplasty of arteries of the upper extremities in patients with extracranial giant-cell arteritis

OBJECTIVES

To evaluate the outcome of balloon angioplasty in the arteries of the upper extremities in patients with giant-cell arteritis (GCA) and stenosing extracranial involvement.

METHODS

Percutaneous transluminal angioplasty (PTA) for symptomatic upper limb artery stenoses (n = 29) and occlusions (n = 1) resistant to medical treatment was carried out in 10 patients (all women, mean age 65 years) with GCA. Vascular lesions were located in the subclavian (n = 4), axillary (n = 10) and brachial (n = 16) arteries. Interventional treatment was accompanied by immunosuppressive drugs in all patients. Follow-up included clinical and serological examination, magnetic resonance angiography and colour duplex ultrasound.

RESULTS

Initial technical success of angioplasty was achieved in the case of all vascular lesions. In five patients, marked recurrent stenoses (vascular territories; n = 10/30) were found during follow-up (mean 24 months). The cumulative primary patency rate was 65.2%. All recurrent lesions developed in the territories of the initial long-segment stenoses. Repeated PTA (vascular territories, n = 8; patients, n = 5) provided a cumulative secondary patency rate of 82.6% and a cumulative tertiary patency rate of 89.7%.

CONCLUSIONS

Despite a tendency to restenoses, balloon angioplasty of the upper-extremity artery, in combination with immunosuppressive treatment, is an efficient method for the treatment of extracranial GCA.