INTRODUCTION
Giant cell arteritis (GCA), or temporal arteritis, is a chronic inflammatory disease affecting the large and medium-sized arteries in persons over the age of 50, with the highest incidence between the ages of 70 and 80 years (1). Most symptoms and signs of GCA are the result of affected cranial branches of arteries originating from the aortic arch, but given the systemic nature of the disease, other blood vessels can be affected too. The diagnosis of GCA should be considered in older patients who complain of new-onset headache, sudden onset of vision disturbances, especially the transient monocular vision loss, jaw claudication, fever of unknown origin, anemia or other systemic symptoms and signs. Elevated erythrocyte sedimentation rate (ESR) is usually present, frequently accompanied by high level of C-reactive protein (CRP) in the serum Current or previous diagnosis of polymyalgia rheumatica (PMR) increases the likelihood of either of these results (2). In approximately 50% of patients, GCA manifests with various visual disturbances. Among the most common ones are the monocular vision loss and anterior ischemic optic neuropathy (AION). It is estimated that binocular blindness will occur in 25–50% of untreated patients with monocular vision loss (3–5).
The main treatment is a high dosage of systemic glucocorticoids, which must be introduced as soon as GCA is diagnosed, especially in patients with recent or imminent vision loss. Treatment should not be delayed while waiting for the results of other diagnostic methods such as temporal artery biopsy, i.e. the results of histological examination of biopsy specimen. For patients who have developed side effects or who depend on high doses of glucocorticoids, treatment can be augmented with methotrexate (MTX) or, as of more recently, interleukin 6 (IL-6) inhibitor tocilizumab (TCZ) (6–9).
In this paper, we present a case of a patient with swollen parotid glands and visual disturbances as part of GCA, with both symptoms manifesting before the onset of headache.
CASE REPORT
The 66-year-old patient was hospitalized at the Department of Ophthalmology due to a monocular vision loss. Two months before admission, the patient experienced parotid gland swelling and thickening of th temporal arteries. A month before admission, she noticed visual disturbances in the left eye on several occasions. The disturbances took the form of transitory “curtain effect” that lasted no longer than 10 minutes, followed by gradual weakening of vision that developed over the course of around 10 days. The patient was examined in another hospital by otorhinolaryngology, neurology and ophthalmology specialists. She underwent the computed tomography (CT) of the head at the same time, which revealed the inflammation of the left maxillary sinus. She was prescribed a 10-day course of cefuroxime, to no effect. Several days before admission to our hospital, she was subfebrile (axillary temperature up to 37.6ºC) and began to experience pain in the jaw and temporal regions. After completely losing vision in her left eye, she was hospitalized at the Department of Ophtalmology, where she was diagnosed with anterior ischemic optic neuropathy (AION) of the left eye. During her hospital stay, we noticed that her right-eye vision was weakening too, so 3 days after hospitalization she was examined by a rheumatology specialist and transferred to the Department of Rheumatology. The patient received intravenous pulse glucocorticoid therapy on the same day (Solu-Medrol, 500 mg/day for 3 days). The treatment was continued with the dosage of 1 mg/kg, with gradual tappering. Her right-eye vision normalized 2 days after the start of the treatment, but left-eye vision loss persisted throughout her hospital stay. The patient had been treated for arterial hypertension and bronchial asthma, and she suffered two cerebrovascular insults (CVI) in 2013 due to the left carotid artery stenosis, for which she underwent a thromboendarterectomy. Upon admission, the patient was afebrile, her vital signs were normal, and she had several crusts that remained after herpes zoster infection in the parieto-occipital region Laboratory test results showed increased ESR (80 mm/h), elevated CRP (41.1 mg/L), leukocytosis (11.5 × 109/L) with neutrophilia (92.7%) and mild hyperglycemia (7.0 mmol/L). Other hematological and biochemistry parameters (erythrocytes, thrombocytes, transaminases, creatinine, electrolytes, C3 and C4 complement) were within normal reference ranges. Color Doppler ultrasound (CDUS) of the temporal arteries showed hypoechoic halo of both temporal arteries. Temporal artery biopsy was performed, and the histological examination determined that the media was thickened, with inflammatory lymphocyte and histiocyte infiltration and presence of multinuclear giant cells (CD68-positive). Magnetic resonance imaging of the brain showed a left supratentorial parietooccipital area of malacia/atrophy of the parenchyma, resembling the sequelae of the chronic vascular lesion, and a smaller chronic lacunar vascular lesion in the left frontal region subcortically. Results of microbiological tests (urine culture, hemoculture), tumor markers (carcinoembryonic antigen [CEA], CA 19-9, CA 125, CA 15-3, alpha fetoprotein [AFP]) and immunological parameters (antinuclear antibodies [ANA], rheumatoid factor [RF], antineutrophil cytoplasmic antibodies [ANCA]) all came back normal. Eight days after the start of the glucocorticoid therapy, follow-up testing showed normalization of inflammation parameters (CRP 2.6 mg/L), and the patient was discharged to home care.
DISCUSSION
According to the American College of Rheumatology (ACR), classification criteria for GCA includes age of 50 years or older, new-onset headache, temporal artery tenderness or decreased temporal artery pulsation, ESR of at least 50 mm/h, and positive artery biopsy results characterized by mononuclear infiltration or granulomatous inflammation (10). Definitive diagnosis is based on histological analysis of temporal artery or diagnostic imaging. Histological and immunohistochemical analyses show inflammation of the arterial wall dominated by CD4+ T lymphocytes and macrophages that frequently show granulomatous organization, forming giant cells. Vascular remodeling caused by inflammation leads to the intimal hyperplasia and occlusion of the lumen, which leads to ischemic complications. Histological specimen to prove GCA is most commonly obtained by the temporal artery biopsy (11). However, in the hands of experienced ultrasound specialists, CDUS can replace biopsy (12).
Our patient met all the criteria for the GCA diagnosis, but interestingly, the headache only began after the first manifestation of visual disturbances. Ordinarily, the onset of headache precedes visual disturbances and is present in approximately 90% of GCA patients. Available literature describes cases with atypical onset of the disease, such as occipital headache, limited range of jaw motion or orofacial pain (13–15). Such atypical onset of the disease, as was the case with our patient, hinders the timely diagnosis and beginning of treatment, which can have far-reaching consequences. The swelling of the parotid glands is an extremely rare symptom of this disease, caused by the vasculitis of the posterior auricular artery (16,17). The patient in question experienced the swelling 2 months before hospitalization, and it subsided spontaneously over the course of approximately one month.
If GCA is suspected and visual disturbances have already manifested, the planned biopsy should not delay the start of the glucocorticoid treatment. According to some studies, temporal artery biopsy performed 1–4 weeks after the start of the glucocorticoid treatment reveals signs of inflammation typical for GCA, providing useful information for diagnosis even during that time (6). Negative biopsy results do not rule out the GCA diagnosis and can be expected in 10–15% of GCA patients (8,12,18). Positron emission tomography (PET), CT, CT angiography (CTA), and magnetic resonance angiography (MRA) lack the resolution for proper visualization of temporal artery (19). That may explain why our patient was not diagnosed with GCA after undergoing CT.
The most serious GCA complication is permanent vision loss, which is usually painless and sudden. It can be partial or complete, monocular or binocular. Permanent vision loss in GCA is the result of AION, central retinal artery occlusion or branch retinal artery occlusion (CRAO/BRAO), posterior ischemic optic neuropathy (PION) or, rarely, cerebral ischemia. Fundoscopy is indicated in patients with subjective change in visual acuity (3,4,18). The first ophthalmological examination of our patient did not reveal anything unusual, while the follow-up examination found the AION of the left eye, which caused the permanent vision loss. The reported recurrence of CVI could also be a consequence of GCA, as CVI is described as part of GCA clinical presentation. However, it does not correspond with the GCA clinical presentation in our patient because it occurred several years earlier.
Given the fact that patients with undiagnosed GCA often “wander” between neurologists, ophthalmologists, infectiologists and rheumatologists, glucocorticoid therapy is usually not introduced in a timely manner in clinical practice (20,21). It can lead to the permanent vision loss and other serious complications of this disease, as was the case with our patient.
CONCLUSION
In this paper we described the case of a patient with temporal arteritis who suffered irreversible vision loss in one eye as the result of delayed introduction of appropriate treatment. This case should alert us to the importance of taking temporal arteritis into consideration as a differential diagnosis in patients older than 50 with amaurosis fugax, even if typical symptoms are missing at the onset of disease. Additionally, bilateral parotid swelling, although exceedingly rare, can be one of the first manifestations of the disease. Good collaboration between ophthalmology and rheumatology specialists, as well as other specialists, is key to early diagnosis and start of appropriate treatment to reduce the risk of permanent vision loss and other effects of the disease.