Thyroiditis with myxoedema and orbital pseudotumour

Difficulties in investigating and treating fibrosing thyroid disorder (overlap of fibrosing variant of Hashimoto's thyroiditis and Riedel's thyroiditis)

A gentleman in his 90s presented with a slowly enlarging goitre over 18 months, causing manifestations of superior vena cava obstruction, dysphagia and hoarseness of voice. Investigations were suggestive of a fibrosing thyroid pathology. Surgical management was avoided due to high surgical risk. Treatment included prednisolone and tamoxifen with palliative management in the event of further medical deterioration. This article illustrates the difficulties in diagnosing and managing fibrosing thyroid diseases.

A rare case of orbital involvement in Riedel's thyroiditis

We report a case of Riedel's thyroiditis in a 59-yr-old Caucasian female. She presented hypothyroidism and a stony hard, painful goiter. Due to fever, a high sedimentation rate and a high C-reactive protein (CRP), as well as high levels of anti-thyroid peroxidase antibodies (anti-TPOab), differential diagnostic considerations included acute and subacute thyroiditis as well as Hashimoto's thyroiditis and thyroid malignancy. At the same time the patient had clinical and radiological features of bilateral orbital pseudotumor with lacrimal gland involvement. During L-thyroxine therapy orbital symptoms and signs improved and thyroid size decreased. This case report serves as a reminder of differential diagnostic considerations in the etiology of goiter as well as ophthalmopathy. Although extremely rare, orbital sclerosing fibrosis can be seen in conjunction with Riedel's thyroiditis as part of multifocal fibrosclerosis.

What is orbital pseudotumor?

We have reviewed the literature in order to delineate the clinicopathologic definition of orbital pseudotumor, also called idiopathic nonspecific orbital inflammation. The clinical picture of orbital pseudotumor varies widely, with signs of mass effect, inflammation and/or infiltration. On computed tomography, orbital pseudotumor presents as a unilateral focal or diffuse mass. The histopathologic hallmark of orbital pseudotumor is a mixed inflammatory infiltrate with fibrosis of varying degree. Contrary to an old belief, orbital pseudotumor is not related to orbital reactive lymphoid hyperplasia (pseudolymphoma) and is not a lymphoid tumor. Atypical histopathologic findings of orbital pseudotumor include dominant sclerosis, granulomatous inflammation, vasculitis, and tissue eosinophilia. In the absence of systemic fibroinflammatory, granulomatous, and vasculitic disease, these atypical histopathologic patterns can be considered to represent subclasses of orbital pseudotumors rather then distinct entities. Clinical and prognostic characteristics of both histopathologically classical and atypical orbital pseudotumors appear to be heterogeneous. The etiology of orbital pseudotumor is unknown, but infection, autoimmune disorder, and aberrant wound healing have all been put forward as possibilities. In conclusion, orbital pseudotumor is one distinct disease albeit with many clinical and histopathologic guises.

Orbital involvement in multifocal fibrosclerosis

Multifocal fibrosclerosis is a condition of unknown aetiology, characterised by fibrous lesions occurring at a variety of sites. Clinical variants include retroperitoneal fibrosis, Riedel's thyroiditis, sclerosing cholangitis, and mediastinal fibrosis. Orbital pseudotumour has been reported as a manifestation of this condition. Three patients with multifocal fibrosclerosis in whom orbital involvement was the dominant feature are described.

Multifocal fibrosclerosis associated with suprasellar and macular lesions

Multifocal fibrosclerosis is a term used to denote a combination of similar fibrous disorders occurring at different anatomical sites and including idiopathic mediastinal and retroperitoneal fibrosis, sclerosing cholangitis, Riedel's thyroiditis, and orbital pseudotumour. This paper reports a patient, known to have retroperitoneal and testicular fibrosis, who suffered visual loss resulting from marked changes in the macular region of one eye and suprasellar extension of a mass in the pituitary fossa. These lesions appear to represent very uncommon manifestations of multifocal fibrosclerosis.

Orbital pseudotumour and lacrimal involvement developing in a patient with Riedel's struma receiving steroids

We present a patient with hypothyroidism secondary to Riedel's struma, treated with thyroxine and prednisolone, who developed clinical and radiological features of a unilateral orbital pseudotumour with lacrimal gland involvement; the histology of which was indistinguishable from that of the thyroid gland.

Pathology of 'pseudotumours' of the orbit: a review

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Inflammatory pseudotumour of the orbit

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Fibrosis of the thyroid and lacrimal glands

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Idiopathic retroperitoneal fibrosis associated with an arteritis

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