Heterotopic ossification (HO), a synonym for osseous metaplasia, is a pathological phenomenon, characterized by abnormal bone formation outside the skeletal system observed commonly in various neoplastic and non-neoplastic diseases. HO occurring in meningioma is exceptionally rare. We reportherein an unusual case of spinal meningioma containing numerous calcified psammoma bodies and extensive HO in a 75-year-old woman, who presented with progressive worsening bilateral lower limb weakness and numbness. The presence of remarkable bone formation within a meningioma is controversial among pathologists; while some regard them as psammomatous meningioma as the primary diagnosis, others prefer osteoblastic meningioma, a form of metaplastic meningioma. There is compelling molecular data to advocate that HO is an active disease process involving metaplastic (osseous) differentiation of meningioma stroma mesenchymal stem-like cells, but not the meningothelial-derived tumor cells. Henceforth, the term "metaplastic meningioma" may not be appropriate in this context. A plausible designation as "psammomatous meningioma with osseous metaplasia" defines this entity more accurately. This paper highlights the need for a unifying nomenclature to reduce diagnostic controversy caused by conflicting terms in the literature. The possible pathogenesis of this intriguing phenomenon is discussed.
Bickerstaff brainstem encephalitis (BBE) is a rare autoimmune encephalitis characterised by ataxia, ophthalmoplegia and altered consciousness. An overlap between BBE with Guillain-Barré syndrome (GBS) shows similar clinical and immunological features. We report a case of BBE with GBS overlap secondary to Chlamydia pneumoniae infection. The triad of altered consciousness, ataxia and ophthalmoplegia were present in the patient. The investigations included cerebrospinal fluid cytoalbuminological dissociation, nerve conduction test that showed prolonged or absent F wave latencies, hyperintensity in the left occipital region on brain MRI and diffuse slow activity on the electroencephalogram. The chlamydia serology was positive indicating a postinfectious cause of BBE syndrome. He required artificial ventilation as his consciousness level deteriorated with tetraparesis, oropharyngeal and respiratory muscle weakness. Immunotherapy with intravenous immunoglobulin and methylprednisolone was commenced. He made good recovery with the treatment. Prompt recognition of this rare condition following chlamydia infection is important to guide the management.
Labrune's syndrome, or leukoencephalopathy with brain calcifications and cysts (LCC), is a rare genetic syndrome with variable neurological presentations. Psychiatric manifestations and involuntary movements are uncommonly reported. We report the case of a 19-year-old female, initially diagnosed with Fahr's syndrome, who presented to us with acute psychosis, abnormal behavior and involuntary movements. Her brain computed tomography showed extensive bilateral intracranial calcifications without cysts. Genetic testing detected two compound heterozygous variants, NR_033294.1 n.*9C>T and n.24C>T, in the SNORD118 gene, confirming the diagnosis of LCC. We discuss the expanding phenotypic spectrum of LCC and provide a literature review on the current diagnosis and management of this rare syndrome.