Orbital Myositis in Churg-Strauss Syndrome

A case of orbital myositis in a patient with Churg-Strauss syndrome(CSS) is reported herein. To our knowledge, this association has been reportedonly once previously.¹ We also describethe previously reported ophthalmic manifestations of CSS.

A 55-year-old woman was referred to our unit with a 1-week history ofredness and pain behind the right eye, which worsened on eye movement.

Her medical history included adult-onset, steroid-dependent asthma,diagnosed at 30 years of age and currently stabilized with inhaled corticosteroiduse. She also had, from allergic rhinitis, nasal polyps and severe sinus diseaserequiring repeated surgery. She had been noted to have peripheral blood eosinophiliaon several occasions for the last 7 years and had a recurrent rash for thelast 4 years involving her trunk and back, responsive to corticosteroid treatmentand found to be interstitial granuloma annulare on tissue biopsy results obtained4 years earlier. A repeated biopsy 1 year later revealed an intense urticarialinflammatory reaction with perivascular eosinophilic and lymphocytic inflammatoryinfiltrates. Peripheral blood eosinophil levels, 4 and 3 years previously,were raised at 2300/µL and 2060/µL, respectively. A bone marrowbiopsy obtained 3 years earlier revealed a marrow eosinophilia and an elevationof eosinophil precursor populations (eosinophil and eosinophil precursors,10%) with normal erythropoiesis, myelopoiesis, marrow cells, and marrow architecture.Findings from bone marrow lymphocyte surface marker analysis and gene rearrangementstudies were normal. Allergies included sulfur, aspirin, and certain foods,for which she had undergone desensitization therapy.

On examination, she had swelling and tenderness of the right upper lidand bony tenderness over the right cheek. Her right conjunctiva was inflamedand edematous with a raised lesion on the inferior aspect (Figure 1A). She had 2 mm of right axial proptosis (Hertel exophthalmometerreadings of 16 mm OS and 14 mm OD, respectively) and a red, swollen, tender,right superior rectus muscle insertion (Figure1B). The right medial and lateral recti insertions also appearedprominent. Visual acuity (using meters) was 6/6 OD and 6/5 OS. Findings froma full, dilated ocular examination of both eyes was otherwise unremarkable.

A computed tomography scan of the orbits showed significant enlargementof the right superior rectus muscle along with some enlargement of the otherrecti. There was also opacification of all paranasal sinuses bilaterally (Figure 2A). Biopsy findings of the rightconjunctival lump were confirmed histologically to be a focal eosinophilicinflammatory cell infiltrate with no granulomata or evidence of vasculitis(Figure 2B). Complete blood cellcount findings were normal, with no evidence of eosinophilia. Rheumatoid factorwas borderline at 20 kIU/L (reference, <20 kIU/L). Other unremarkable resultsincluded serum electrolyte levels; liver function tests; thyroid functiontests; serum angiotensin-converting enzyme, antinuclear antibody, and antineutrophilcytoplasmic antibody levels; chest x-ray; echocardiography; barium swallow;and stool examination.

She began a reducing course of oral prednisolone (initial dose, 60 mg),1 day prior to undergoing conjunctival biopsy, and her myositis resolved duringthe following 2 weeks.

Five months after her episode of myositis, she underwent a biopsy ofnasal tissue during functional endoscopic sinus surgery for ongoing sinusitis.The biopsy findings revealed nonspecific inflammatory nasal polyps with prominenteosinophilia. Again, no granulomatous inflammation or vasculitis was identified.These results were considered consistent with CSS, however nondiagnostic ina pathological sense.

Churg-Strauss syndrome is an uncommon, systemic, vasculitic disorderand is largely typified by a history of asthma, allergic disease not includingdrug allergy, and eosinophilia (≥10%) on differential white blood cellcount.² Churg-Strauss syndrome classicallyaffects the lung and paranasal sinuses, but extrapulmonary manifestations,namely skin, cardiac, and gastrointestinal, are also commonly described. Ocularfeatures are unusual.¹ Early recognitionof the ocular features of this syndrome, and early institution of appropriatetreatment, may minimize complications and potentially completely reverse thedisease process.

We report a case of orbital myositis in a patient with CSS. Our patientmeets the American College of Rheumatology 1990 criteria for CSS, with a documentedhistory of asthma, eosinophilia (25% differentiated white blood cells), andallergic disease, namely, allergic rhinitis, pansinusitis, and food allergy.² Conjunctival biopsy revealed florid extravascularinfiltration of eosinophils; however, there were no granulomas or vasculitis.Myositis was diagnosed on clinical and radiological grounds. The conjunctivallump and the superior rectus myositis arose simultaneously and, therefore,can be considered the same disease process, particularly so because both theconjunctival lesion and myositis resolved concurrently with the administrationof oral steroids.

The eosinophilic tissue infiltrative phase of CSS is well described,and the lack of histological evidence of granulomas or vasculitis may occurwith biopsy techniques such as fine-needle aspiration or bronchoalveolar lavage.However, other explanations include disease suppression by corticosteroiduse, or a prevasculitic phase of the illness. A forme fruste type of CSS isdescribed, in which the disease has been partially or completely suppressedby systemic or inhaled corticosteroid therapy for asthma and only appearsclinically when changes in steroid therapy are made.³ Thisis illustrated by our case, in which the biopsy did not reveal any evidenceof granulomata or vasculitis in a patient taking inhaled corticosteroids,with a history of oral steroid use, and 1-day use of oral prednisolone. Therapid response to corticosteroids, as seen in this case, is typical of CSS.^3,4

Ocular features of CSS in the literature are relatively sparse but varied.These include conjunctival nodules,^1,5,6 cornealulcer,⁷ episcleritis,⁵ uveoscleritis,^5,7 ischemic optic neuropathy, amaurosisfugax,^1,6,7 centralretinal vein occlusion, central and branch retinal artery occlusion, retinalvasculitis,¹ retinal hemorrhage,⁷ cranial nerve palsies,^1,7 andorbital inflammatory syndrome.¹

A review by Takanashi et al¹ describes15 cases in the literature that meet the American College of Rheumatology1990 criteria for the classification of CSS. This includes a case of dacryoadenitisand myositis. On initial examination, this patient had proptosis and radiologicallyconfirmed symmetrical lacrimal gland and superior and lateral rectus muscleswelling. Biopsy findings of the lacrimal gland and lateral rectus musclerevealed extravascular infiltration of eosinophils.

Churg-Strauss syndrome may be difficult to diagnose.^2,4 Thecombination of asthma, eosinophilia, and a history of allergies must raisethe suspicion of CSS and the possibility of vasculitis. However, biopsy ofocular tissue may give somewhat indeterminate results.^1,6

To our knowledge, orbital myositis has only once been previously reported.¹ In conclusion, we present a case of superior rectusmuscle myositis due to CSS. The concurrent association with an eosinophilicconjunctival nodule further illustrates the heterogeneity of the ocular manifestationsof CSS.

Corresponding author: Dinesh Selva, FRACS, FRANZCO, Oculoplasticand Orbital Clinic, Department of Ophthalmology, Royal Adelaide Hospital,North Terrace, Adelaide, Australia 5000 (e-mail: Awestwoo@mail.rah.sa.gov.au).