Bilateral Non-arteritic Anterior Ischaemic Optic Neuropathy as the Presentation of Systemic Amyloidosis

Bilateral Progressive Optic Neuropathy in a Patient with Familial Amyloid Polyneuropathy: Amyloid Deposits in the Optic Nerve Head?

Familial amyloid polyneuropathy is a rare autosomal dominant hereditary disease. Optic nerve involvement is frequently observed secondary to uncontrolled glaucoma but, rarely, an ischaemic optic neuropathy can occur. In this case report we describe a patient who presented with bilateral progressive visual loss and constriction of his visual fields. Fundus examination showed intense paleness of both optic discs with elevated, poorly defined margins that seemed to be infiltrated. Fundus autofluorescence and enhanced-depth imaging optical coherence tomography ruled out the presence of optic disc drusen. Orbital magnetic resonance imaging ruled out any sign of orbital compression, inflammation or infiltration of the optic nerve. The mechanism of small vessel amyloid infiltration and a possible vessel compression by amyloid in the optic nerve head is discussed.

Temporal Artery Vascular Diseases

In the presence of temporal arteritis, clinicians often refer to the diagnosis of giant cell arteritis (GCA). However, differential diagnoses should also be evoked because other types of vascular diseases, vasculitis or not, may affect the temporal artery. Among vasculitis, Anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis is probably the most common, and typically affects the peri-adventitial small vessel of the temporal artery and sometimes mimics giant cell arteritis, however, other symptoms are frequently associated and more specific of ANCA-associated vasculitis prompt a search for ANCA. The Immunoglobulin G4-related disease (IgG4-RD) can cause temporal arteritis as well. Some infections can also affect the temporal artery, primarily an infection caused by the varicella-zoster virus (VZV), which has an arterial tropism that may play a role in triggering giant cell arteritis. Drugs, mainly checkpoint inhibitors that are used to treat cancer, can also trigger giant cell arteritis. Furthermore, the temporal artery can be affected by diseases other than vasculitis such as atherosclerosis, calcyphilaxis, aneurysm, or arteriovenous fistula. In this review, these different diseases affecting the temporal artery are described.

Transthyretin amyloidosis and herpes zoster infection: a mimic of temporal arteritis

We describe the case of a patient who presented with symptoms of persistent headaches, left-sided facial pain and blurry vision of the left eye. The patient had recovered from a herpes zoster infection of the V1 division of the trigeminal nerve 1 month prior. Serum inflammatory markers were elevated, raising concern for temporal arteritis. Empiric high-dose prednisone was initiated. Bilateral temporal artery biopsies were performed but did not show evidence of vasculitis or multinucleated giant cells. Instead, extracellular material deposits were present within the vessel walls. Congo red staining was diagnostic for amyloidosis. Liquid chromatography and mass spectrometry identified the amyloid fibrils to be transthyretin-type (ATTR) consistent with age-related amyloidosis. Temporal artery involvement of amyloidosis is rare but when present is most often due to light chain amyloidosis. Based on our review of the literature, only a few cases of temporal artery ATTR amyloidosis have been reported.

Clinical and Histopathological Features of Gelsolin Amyloidosis Associated with a Novel GSN Variant p.Glu580Lys

Simple Summary

Gelsolin amyloidosis is a rare autosomal dominant genetic disease, which typically affects the cornea, skin and sometimes other organ systems and is caused by mutations in a gene coding for gelsolin protein (GSN). We describe a novel mutation of GSN gene, p.Glu580Lys, associated with gelsolin amyloidosis in six members of a two-generation family, who exhibited lattice corneal dystrophy, loose facial skin and irregular heart rhythm. In one patient we reported optic nerve impairment, which is possibly a novel feature associated with gelsolin amyloidosis.

Abstract

Gelsolin amyloidosis typically presents with corneal lattice dystrophy and is most frequently associated with pathogenic GSN variant p.Asp214Asn. Here we report clinical and histopathological features of gelsolin amyloidosis associated with a novel GSN variant p.Glu580Lys. We studied DNA samples of seven members of a two-generation family. Exome sequencing was performed in the proband, and targeted Sanger sequencing in the others. The heterozygous GSN variant p.Glu580Lys was identified in six patients. The patients exhibited corneal dystrophy (5/6), loose skin (5/6) and/or heart arrhythmia (3/6) and one presented with bilateral optic neuropathy. The impact of the mutation on the protein structure was evaluated in silico. The substitution is located in the fifth domain of gelsolin protein, homologous to the second domain harboring the most common pathogenic variant p.Asp214Asn. Structural investigation revealed that the mutation might affect protein folding. Histopathological analysis showed amyloid deposits in the skin. The p.Glu580Lys is associated with corneal dystrophy, strengthening the association of the fifth domain of gelsolin protein with the typical amyloidosis phenotype. Furthermore, optic neuropathy may be related to the disease and is essential to identify before discussing corneal transplantation.

False positives in the ultrasound diagnosis of giant cell arteritis: some diseases can also show the halo sign

Objectives

To describe the frequency and causes for the presence of a halo sign on the ultrasound of patients without a diagnosis of GCA.

Methods

In total, 305 patients with temporal artery colour Doppler ultrasound showing the presence of halo sign (intima-media thickness ≥0.34 mm for temporal arteries [TAs] and ≥1 mm for axillary arteries) were included, and their medical records were reviewed. The clinical diagnosis based on the evolution of the patient over at least one year was established as the definitive diagnosis.

Results

Fourteen of the 305 (4.6%) patients included showed presence of the halo sign without final diagnosis of GCA: 12 patients in the TAs (86%), and two patients with isolated AAs involvement (14%). Their diagnoses were PMR (n = 4, 29%); atherosclerosis (n = 3, 21%); and non-Hodgkin lymphoma type T, osteomyelitis of the skull base, primary amyloidosis associated with multiple myeloma, granulomatosis with polyangiitis, neurosyphilis, urinary sepsis and narrow-angle glaucoma (n = 1 each, 7%).

Conclusion

The percentage of halo signs on the ultrasound of patients without GCA is low, but it does exist. There are conditions that may also show the halo sign (true positive halo sign), and we must know these and always correlate the ultrasound findings with the patient’s clinic records.

Temporal artery involvement in AL amyloidosis: an important differential diagnosis for giant cell arteritis. A case report and literature review

AL amyloidosis (AL) is a systemic disorder due to extracellular tissue deposition of amyloid fibrils, composed of immunoglobulin light chains. Since the description of AL involving temporal arteries in 1986, this disorder has been known as one of the differential diagnoses of giant cell arteritis (GCA). We encountered a case of an elderly female presenting with headache and tender and enlarged temporal arteries, that was pathologically diagnosed with temporal artery involvement of AL due to Bence-Jones-type MM. To our knowledge, this was the first case of AL with temporal artery involvement in Japan, that presented with GCA-like features. Literature review of AL cases with temporal artery involvement showed close similarity between these disorders, but suggested that vasculature involvement (extremity claudication, kidney or heart), macroglossia, carpal tunnel syndrome and normal or low (<0.5 mg/dL) CRP levels may predict AL rather than GCA. Physicians should keep in mind that AL involving temporal arteries can be a pitfall in the diagnosis of GCA, as seen in our and previous cases.

Immunoglobulin Light-Chain Amyloidosis: Clinical Presentations and Diagnostic Approach

Systemic immunoglobulin light-chain (AL) amyloidosis is a rare disorder arising from a plasma cell clone that produces misfolded immunoglobulin light chains, which are deposited in various tissues and organs as amyloid fibrils. Signs and symptoms are typically vague and overlap with those arising from other common diseases; consequently, diagnosis of AL amyloidosis is challenging for clinicians. Substantial delays between onset of symptoms and diagnosis are common, and result in poorer outcomes, particularly in patients with cardiac AL amyloidosis and others who develop advanced organ dysfunction. With the need to identify AL amyloidosis as early as possible, it is important for health-care practitioners, including advanced practice clinicians and nurses, to be aware of the hallmark presenting signs and symptoms, as well as the latest practice for evaluation and diagnosis. Increased awareness of signs and symptoms associated with AL amyloidosis, particularly relating to the most frequently involved organs, the heart and kidneys, represents an opportunity for achieving earlier diagnosis. Here we review these issues in AL amyloidosis, summarize the key presenting symptoms that clinicians need to be alert to, and discuss the latest diagnostic tests, with the aim of expediting patient identification and diagnosis with the goal of improving patient outcomes.