Manifestations ophtalmologiques de la maladie de Horton

Halo sign on temporal artery ultrasound versus temporal artery biopsy for giant cell arteritis

BACKGROUND

Giant cell arteritis (GCA) is a systemic, inflammatory vasculitis primarily affecting people over the age of 50 years. GCA is treated as a medical emergency due to the potential for sudden, irreversible visual loss. Temporal artery biopsy (TAB) is one of the five criteria of the American College of Rheumatology (ACR) 1990 classification, which is used to aid the diagnosis of GCA. TAB is an invasive test, and it can be slow to obtain a result due to delays in performing the procedure and the time taken for histopathologic assessment. Temporal artery ultrasonography (US) has been demonstrated to show findings in people with GCA such as the halo sign (a hypoechoic circumferential wall thickening due to oedema), stenosis or occlusion that can help to confirm a diagnosis more swiftly and less invasively, but requiring more subjective interpretation. This review will help to determine the role of these investigations in clinical practice.

OBJECTIVES

To evaluate the sensitivity and specificity of the halo sign on temporal artery US, using the ACR 1990 classification as a reference standard, to investigate whether US could be used as triage for TAB. To compare the accuracy of US with TAB in the subset of paired studies that have obtained both tests on the same patients, to investigate whether it could replace TAB as one of the criteria in the ACR 1990 classification.

SEARCH METHODS

We used standard Cochrane search methods for diagnostic accuracy. The date of the search was 13 September 2022.

SELECTION CRITERIA

We included all participants with clinically suspected GCA who were investigated for the presence of the halo sign on temporal artery US, using the ACR 1990 criteria as a reference standard. We included studies with participants with a prior diagnosis of polymyalgia rheumatica. We excluded studies if participants had had two or more weeks of steroid treatment prior to the investigations. We also included any comparative test accuracy studies of the halo sign on temporal artery US versus TAB, with use of the 1990 ACR diagnostic criteria as a reference standard. Although we have chosen to use this classification for the purpose of the meta-analysis, we accept that it incorporates unavoidable incorporation bias, as TAB is itself one of the five criteria. This increases the specificity of TAB, making it difficult to compare with US. We excluded case-control studies, as they overestimate accuracy, as well as case series in which all participants had a prior diagnosis of GCA, as they can only address sensitivity and not specificity.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion in the review. They extracted data using a standardised data collection form and employed the QUADAS-2 tool to assess methodological quality. As not enough studies reported data at our prespecified halo threshold of 0.3 mm, we fitted hierarchical summary receiver operating characteristic (ROC) models to estimate US sensitivity and also to compare US with TAB. We graded the certainty of the evidence using the GRADE approach.

MAIN RESULTS

Temporal artery ultrasound was investigated in 15 studies (617 participants with GCA out of 1479, 41.7%), with sample sizes ranging from 20 to 381 participants (median 69). There was wide variation in sensitivity with a median value of 0.78 (interquartile range (IQR) 0.45 to 0.83; range 0.03 to 1.00), while specificity was fair to good in most studies with a median value of 0.91 (IQR 0.78 to 1.00; range 0.40 to 1.00) and four studies with a specificity of 1.00. The hierarchical summary receiver operating characteristic (HSROC) estimate of sensitivity (95% confidence interval (CI)) at the high specificity of 0.95 was 0.51 (0.21 to 0.81), and 0.84 (0.58 to 0.95) at 0.80 specificity. We considered the evidence on sensitivity and specificity as of very low certainty due to risk of bias (-1), imprecision (-1), and inconsistency (-1). Only four studies reported data at a halo cut-off > 0.3 mm, finding the following sensitivities and specificities (95% CI): 0.80 (0.56 to 0.94) and 0.94 (0.81 to 0.99) in 55 participants; 0.10 (0.00 to 0.45) and 1.00 (0.84 to 1.00) in 31 participants; 0.73 (0.54 to 0.88) and 1.00 (0.93 to 1.00) in 82 participants; 0.83 (0.63 to 0.95) and 0.72 (0.64 to 0.79) in 182 participants. Data on a direct comparison of temporal artery US with biopsy were obtained from 11 studies (808 participants; 460 with GCA, 56.9%). The sensitivity of US ranged between 0.03 and 1.00 with a median of 0.75, while that of TAB ranged between 0.33 and 0.92 with a median of 0.73. The specificity was 1.00 in four studies for US and in seven for TAB. At high specificity (0.95), the sensitivity of US and TAB were 0.50 (95% CI 0.24 to 0.76) versus 0.80 (95% CI 0.57 to 0.93), respectively, and at low specificity (0.80) they were 0.73 (95% CI 0.49 to 0.88) versus 0.92 (95% CI 0.69 to 0.98). We considered the comparative evidence on the sensitivity of US versus TAB to be of very low certainty because specificity was overestimated for TAB since it is one of the criteria used in the reference standard (-1), together with downgrade due to risk of bias (-1), imprecision (-1), and inconsistency (-1) for both sensitivity and specificity.

AUTHORS' CONCLUSIONS

There is limited published evidence on the accuracy of temporal artery US for detecting GCA. Ultrasound seems to be moderately sensitive when the specificity is good, but data were heterogeneous across studies and either did not use the same halo thickness threshold or did not report it. We can draw no conclusions from accuracy studies on whether US can replace TAB for diagnosing GCA given the very low certainty of the evidence. Future research could consider using the 2016 revision of the ACR criteria as a reference standard, which will limit incorporation bias of TAB into the reference standard.

Ocular Complications of Giant Cell Arteritis: An Acute Therapeutic Emergency

The risk of blindness, due to acute ischemic ocular events, is the most feared complication of giant cell arteritis (GCA) since the middle of the 20th century. A decrease of its rate has occurred after the advent of corticoid therapy for this vasculitis, but it seems to have stabilized since then. Early diagnosis and treatment of GCA is key to reducing its ocular morbidity. However, it is not uncommon for ophthalmological manifestations to inaugurate the disease, and the biological inflammatory reaction may be mild, making its diagnosis more challenging. In recent years, vascular imaging has opened up new possibilities for the rapid diagnosis of GCA, and ultrasound has taken a central place in fast-track diagnostic processes. Corticosteroid therapy remains the cornerstone of treatment and must begin immediately in patients with visual symptoms and suspicion of GCA. In that situation, the administration route of corticotherapy, intravenous or oral, is less important than its speed of delivery, any hour of delay worsening the prognosis.

FLASH: A Novel Tool to Identify Vision-Threating Eye Emergencies

BACKGROUND

Two million patients visit emergency departments due to eye complaints annually in the United States, yet nearly one-quarter of these visits are for non-urgent ocular problems. Other patients often present a significant length of time after the onset of their symptoms, which may cause progression to irreversible vision loss. A major reason for this discrepancy is that many patients are unsure what symptoms constitute eye emergencies. The challenge is helping patients understand what constitutes a vision-threatening eye emergency, as well as the risks and complications that are associated with delaying their visit to the ophthalmologist or Emergency Department.

OBJECTIVES

To describe relevant literature on incidence, prevalence, presentation times, associated prognoses, risks, and complications of individual vision-threating eye emergencies, and present a novel acronym, FLASH (Floaters and flashes, Loss of vision, Aching pain, Second Image, Help), to better educate patients at risk for these conditions, fostering better symptom recognition and timely care. This manuscript is aimed at reaching public health departments, educational institutions, primary care offices and eye care centers as part of a dedicated patient education effort for vision-threatening eye emergencies.

DESIGN / METHODS

Narrative overview of the available literature on specific eye conditions presenting with the aforementioned symptoms, synthesizing findings retrieved from searches of computerized databases and authoritative texts.

CONCLUSIONS

In each condition presented in this article, symptom interval significantly impacts treatment prognoses. The cited literature demonstrates that patients often present late in emergent eye conditions resulting in vision loss.

[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.

Anterior Uveitis with Negative Work-up: Giant Cell Arteritis Remains the Pet Peeve

BACKGROUND

Giant Cell Arteritis (GCA), is the most common primary vasculitis. It affects large vessels such as the aorta and its branches. According to Chapel Hill Consensus, GCA is one of the larger vessel vasculitis. The underlying mechanism involves inflammation of the large arteries. The most frequent presentation consists of headache, polymyalgia, and jaw claudication. GCA can put the visual prognosis at risk, and rapid diagnosis is compulsory. Cotton wool spots, due to focal inner retinal ischemia, are an early diagnostic ophthalmological sign. The most frequent presentation is a rapid, partial or complete blindness. However, atypical presentations, such as uveitis, especially in the anterior chamber, can delay diagnosis.

CASE REPORT

We report a 75-year-old woman with GCA who initially presented with anterior uveitis and without any other clinical sign. At the beginning, there was the only ophthalmic sign and systemic inflammation, the all exhaustive work-up including positron emission tomography (PET) scan was negative. The biology was fully normal without auto-immune profile (Angiotensin converting enzyme level, Interferon Gamma Release Assay, Syphilis serology, antinuclear antibody titer, Rheumatoid factor, CCP antibodies, and chest x-ray were normal. HLA B27 was negative). In the following weeks, she subsequently developed large vessel vasculitis with headache and more typical sign. She developed cotton wool spots linked to retinal arteriolar hypoperfusion. Anterior uveitis has been reported rarely in GCA and moreover, it is very uncommon at the early stages of GCA. Our case stresses that uveitis onset can precede large vessels vasculitis and typical symptoms of GCA. PET-scan is a useful tool for atypical GCA, but its sensitivity is not perfect, and its repetition can be helpful in selected cases such as that of this patient.

Combined bilateral ophthalmic artery occlusion & central retinal vein occlusion from presumed giant cell arteritis

Purpose

To report on a severe case of presumed giant cell arteritis (GCA) presenting with partial and complete ophthalmic artery occlusion along with bilateral central retinal vein occlusions (CRVO).

Observations

A 73-year-old female presented with bilateral complete vision loss of sudden onset. The patient also experienced a mild frontal headache prior to onset of vision loss. Fundus examination revealed bilateral central retinal artery occlusion (CRAO) and CRVO. Subsequent fluorescein angiography indicated partial right ophthalmic artery occlusion and complete left ophthalmic artery occlusion. Acute phase reactants were elevated. The patient was clinically diagnosed with GCA and intravenous (IV) steroids were initiated. Four days later, a temporal artery biopsy (TAB) was performed and resulted as negative for granulomatous inflammation. The patient did not regain vision and remained with no light perception (NLP) in both eyes.

Conclusions

and Importance: This case highlights the discrepancy between clinical diagnosis and pathologic tissue diagnosis in a patient that presented with such extensive ocular vasculitic disease. Such extensive bilateral disease has not been reported. In addition, there are few studies regarding the effect of pulse-dosed IV steroids on TAB results. This case report suggests that the gradual histologic changes that occur over one or two weeks while on oral steroids may occur over three to four days while on high dose IV steroids, necessitating early biopsy.

[Horton disease in the elderly patient]

Horton disease is difficult to diagnose in the elderly, due to the non-specificity of clinical signs. When evoked in the case of recent headaches, laboratory tests must be carried out to look for signs of inflammation.