A 40-year-old woman presented with a side-locked headache with autonomic features, which then switched sides before reverting to the original side. The atypical features of side swapping, partial response to indometacin and abnormal optic disc appearances ultimately led to a diagnosis of recurrent posterior scleritis. We discuss the differential diagnosis of trigeminal autonomic cephalgias and its secondary causes, and provide practical pointers for its investigation and management.
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A 40-year-old right-handed woman woke with a severe (10/10) left-sided persistent sharp headache associated with unilateral lacrimation. The pain was mainly orbitofrontal. A few days later, her left eye appeared red. The unilateral left-sided headache was unremitting for 2 weeks with superimposed exacerbations. Then overnight her symptoms—including the pain, lacrimation and red eye—switched to the right side for a further two weeks before reverting back to the left eye, where they persisted until neurological review. She reported some pain on looking up or down with the affected eye. Otherwise, she had no other visual or neurological symptoms or systemic features. She worked as a nurse.
On examination, her blood pressure was 124/74 mm Hg. She had an injected red left eye. There was mild tenderness over the left greater occipital nerve. Her visual acuities were 6/6 (right) and 6/7.5 (left eye). There was no relative afferent pupillary defect or colour desaturation. Her optic disc margins were indistinct, especially the left, with no spontaneous venous pulsations (figure 1). Her reflexes were brisk but symmetrical with bilateral flexor plantars. The remaining neurological examination was normal.
MR scan of brain and orbits with contrast was reported as normal. CT venogram was normal. Her cerebrospinal fluid (CSF) opening pressure and basic constituents were normal, but subsequently oligoclonal bands were found in the CSF only.
Ibuprofen, paracetamol and triptans had not alleviated her symptoms. Two months after the onset of her symptoms, she received a left greater occipital nerve injection with modest benefit (severity reduced to 5/10). A subsequent indometacin trial gave a better response, reducing the pain severity to 2/10, though her symptoms recurred on tapering the dose.
We initially considered side-switching hemicrania continua, but given the atypical clinical features of abnormal optic disc appearances and lack of absolute response to indometacin, we involved ophthalmology colleagues. Ophthalmology review three months after symptoms onset found hyperaemia in the superior temporal bulbar conjunctiva of the left eye, which was tender to palpate and non-blanching after 10% phenylephrine. Ultrasound B-scan confirmed optic disc drusen as the cause for her indistinct disc margins. A further ultrasound scan confirmed scleritis, giving a diagnosis of recurrent alternating (left>right) scleritis. There were no other systemic symptoms to suggest an associated autoimmune or inflammatory condition. A comprehensive list of haematological, biochemical, autoimmune and serological bloods tests gave normal results (serum ACE, immunoglobulins, serum protein electrophoresis, antinuclear antibody, antinuclear cytoplasmic antibody, anticyclic citrullinated peptide, lupus anticoagulant, anticardiolipin antibodies, syphilis and HIV). A whole-body CT positron-emission tomography excluded an occult inflammatory condition. She responded promptly to a reducing prednisolone taper; she remains well and has not required further immunosuppression.
Scleritis: diagnosis and management
Scleritis is inflammation of the sclera, the outer opaque wall of the eye. The two forms are anterior scleritis, visible on examination and characterised by increased hyperaemia over the affected area of the sclera; and posterior scleritis, not directly visible but identified on imaging such as B-scan ultrasound or MRI.
The characteristic symptoms of scleritis are ocular pain and/or headache, especially worse at night, due to dependent or positional tissue swelling. Patients with anterior scleritis commonly also have blurred vision and a red eye (focal or diffuse). Episcleritis is a more superficial inflammation of the episcleral layer overlying the sclera, but it can be difficult to distinguish from scleritis. Phenylephrine 10% drops constrict the superficial (episcleral) congested vessels but not the deeper (scleral) vessels, confirming the diagnosis.
A retrospective review of 114 patients with posterior scleritis (2004–2013) found a mean age of 46 years; 71% were women and 40% had an associated autoimmune condition.1
It is essential to treat scleritis to prevent visual loss and progressive destruction of the eye. Mild-to-moderate scleritis can usually be controlled with systemic non-steroidal anti-inflammatory drugs, with or without topical corticosteroid eye drops. Patients who do not respond to this combined treatment require escalation to the use of systemic corticosteroids or systemic immunosuppressive agents.
The most common autonomic features in the trigeminal autonomic cephalgias are lacrimation, nasal congestion, conjunctival injection and ptosis. Trigeminal autonomic cephalgias comprise a spectrum of headaches of different durations, from short-lasting unilateral neuralgiform headaches with autonomic features to the longer-lasting cluster headaches, paroxysmal hemicrania and hemicrania continua.
Hemicrania continua is characteristically an unremitting unilateral headache (usually less severe than cluster headache) with superimposed exacerbations, similar to this case. By definition, there must be an absolute response to a trial of indometacin. Oral indometacin is a more pragmatic choice than intramuscular injection. If there are no contraindications, the dose is titrated to a maximum of 75 mg three times daily over 2 weeks. Usually there is an absolute response within the first week or two. Although this patient showed a significant response to indometacin, it was not absolute. Side-switching hemicrania continua (such as this) is unusual.2
It is important to remember that trigeminal autonomic cephalgias may be primary or secondary. Secondary causes include numerous intracranial and extracranial neurovascular and structural lesions.3 The unusual features in this case were the lack of absolute response to indometacin, the recurrent side-switching symptoms and pain on eye movements. Without signs of optic neuritis, the local eye pain suggested an inflammatory eye disorder. In retrospect, this patient's MR scan of orbits showed abnormal sclera (figure 2). Both glaucoma and scleritis should be considered in the differential diagnosis of secondary trigeminal autonomic cephalgia, as without correct diagnosis and treatment there may be irreversible visual compromise.
The diagnosis of hemicrania continua requires an absolute response to indometacin; additional unusual features (atypical symptoms, persistent signs) require exclusion of secondary causes.
The combination of red eye and orbitofrontal headache suggests primary trigeminal autonomic cephalgia; but also consider acute glaucoma, scleritis, uveitis or episcleritis.
Scleritis may resemble conjunctivitis but is more painful; if not treated with immunosuppression, it can cause visual loss.
Contributors AA-M wrote and edited the manuscript and performed literature review. JH wrote parts of the manuscript on scleritis, provided figure 1 and performed literature review. MW reviewed and edited manuscript and was involved in the care of the patient. MP provided MR images and descriptions for figure 2. SG was involved in the care of the patient and edited the manuscript section on scleritis. SV was the neurology consultant in charge of the care of the patient, was involved in writing and editing the manuscript and performed literature review.
Competing interests None declared.
Patient consent Obtained.
Provenance and peer review Not commissioned; externally peer reviewed. This paper was reviewed by Mark Lawden, Leicester, UK.
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