Niamh Bermingham

Atypical presentation of macrophagic myofasciitis 10 years post vaccination.

Macrophagic myofasciitis (MMF) is an uncommon inflammatory disorder of muscle believed to be due to persistence of vaccine-derived aluminium hydroxide at the site of injection. The condition is characterised by diffuse myalgias, arthralgia and fatigue. We describe a patient with histologically confirmed MMF whose presentation was atypical with left chest and upper limb pain beginning more than 10 years post vaccination. Treatment with steroids led to symptomatic improvement. Although rare, clinicians should consider MMF in cases of atypical myalgia.

The novel Tau mutation G335S: clinical, neuropathological and molecular characterization

Mutations in Tau cause the inherited neurodegenerative disease, frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17). Known coding region mutations cluster in the microtubule-binding region, where they alter the ability of tau to promote microtubule assembly. Depending on the tau isoforms, this region consists of three or four imperfect repeats of 31 or 32 amino acids, each of which contains a characteristic and invariant PGGG motif. Here, we report the novel G335S mutation, which changes the PGGG motif of the third tau repeat to PGGS, in an individual who developed social withdrawal, emotional bluntness and stereotypic behavior at age 22, followed by disinhibition, hyperorality and ideomotor apraxia. Abundant tau-positive inclusions were present in neurons and glia in the frontotemporal cortex, hippocampus and brainstem. Sarkosyl-insoluble tau showed paired helical and straight filaments, as well as more irregular rope-like filaments. The pattern of pathological tau bands was like that of Alzheimer disease. Experimentally, the G335S mutation resulted in a greatly reduced ability of tau to promote microtubule assembly, while having no significant effect on heparin-induced assembly of recombinant tau into filaments.

Polyarteritis nodosa presenting with clinical and radiologic features suggestive of polymyositis.

We report a patient who presented with clinical and MRI findings suggestive of polymyositis but, in whom, muscle biopsy disclosed a strikingly different diagnosis. A 65-year-old woman presented with 3-week history of bilateral proximal muscle pain and weakness. Laboratory investigations showed markedly elevated inflammatory markers and mildly elevated muscle enzymes. MRI scans of lower limbs showed features suggestive of polymyositis. However, muscle biopsy showed features of a polyarteritis-type vasculitis affecting an intramuscular blood vessel. Our reports highlight the critical role of muscle biopsy in establishing the correct diagnosis in patients with suspected myositis.

Spontaneous haemorrhage and rupture of third ventricular colloid cyst.

Acute bleeding within a colloid cyst of the third ventricle represents a rare event causing sudden increase in the cyst volume that may lead to acute hydrocephalus and rapid neurological deterioration. We report a case of spontaneous rupture of haemorrhagic third ventricular colloid cyst and its management. A 77-year-old ex-smoker presented with unsteady gait, incontinence and gradually worsening confusion over a 3-week period. Brain CT scan findings were highly suggestive of a third ventricular colloid cyst with intraventricular rupture. He underwent cyst excision and histopathology, which confirmed the radiological diagnosis with evidence of haemorrhage within the cyst. A ventriculo peritoneal shunt was performed for delayed hydrocephalus. Surgical management of these patients must include emergency ventriculostomy followed by prompt surgical removal of the haemorrhagic cyst.

“Unusual brain stone”: heavily calcified primary neoplasm with some features suggestive of angiocentric glioma

This 40-year-old man presented with a 5-month history of progressive right-sided headache associated with visual blurring. He also had a history of epilepsy but had been seizure free with medication for the past 10 years. An initial CT scan of his brain performed 16 years previously had revealed a small area of calcification in the right parietal region. In the current presentation, he had a left-sided homonymous hemianopia but no other neurological deficits. A CT scan of his brain showed a much larger calcified, partly cystic lesion in the right parietal region. Because he was symptomatic, the lesion was excised and the cyst was drained. Histological examination of the excised tissue showed an unusual primary tumor that was difficult to classify but had some features of angiocentric glioma. The heavy calcification, mixed-density cell population, and regions with features of angiocentric glioma were most unusual. The patient remained asymptomatic 5 years after surgery, and follow-up scans did not show recurrence.

Isolated Cerebellar Spindle Cell Pseudotumor Caused by Mycobacterium Avium-Intracellulare Complex in a Patient without AIDS

BACKGROUND Spindle cell pseudotumors are formed by histiocytes in response to infection by Mycobacterium avium-intracellulare complex (MAC) and are rare in patients without AIDS. CASE DESCRIPTION A 66-year-old man presented with neck pain, ataxia, and a history of sarcoidosis. A cerebellar lesion was identified on magnetic resonance imaging and surgically excised. Histopathology revealed this to be a spindle cell pseudotumor and MAC was isolated by bacterial culture of cerebrospinal fluid. Hematology revealed cluster of differentiation 4 lymphocytopenia but human immunodeficiency virus serology was negative. The patient was commenced on antimicrobial treatment that included a macrolide and remained well at 1 year follow-up. CONCLUSIONS This rare presentation of isolated intracranial MAC was treated with surgical excision and antimicrobials with a good outcome.

Interdural Spinal Cyst: A Rare Clinical Entity.

BACKGROUND For more than 2 decades, dural spinal cysts have been broadly classified as extradural and intradural. CASE DESCRIPTION A 40-year-old woman presented with radicular thoracic pain. Intraoperative findings showed the cyst to be present within the dura itself. CONCLUSIONS We suggest a revised classification of spinal dural cysts. This case highlights that, during surgery for spinal meningeal cysts, surgeons should bear in mind the possibility of an interdural cyst. This may help avoid inadvertent tears in the deep layers of such cysts, thus maintaining dural patency.

Sciatica as a presenting feature of thyroid follicular adenocarcinoma in a 79-year-old woman

The authors describe an unusual case of metastatic thyroid follicular adenocarcinoma presenting with sciatica in a 79-year-old woman. The primary thyroid tumour was undiagnosed until this clinical presentation. The patient gave a short history of back pain and right-sided sciatica, which was progressive and nocturnal in nature. Neuroimaging revealed an enhancing intradural mass lesion, which was completely excised through a right L1-L3 hemilaminectomy. Histopathological examination of the excised tissue revealed a follicular thyroid carcinoma. Subsequent metastatic investigation revealed a heterogeneously attenuating mixed solid cystic mass in a retrosternal thyroid gland, with multiple solid pulmonary nodules suggestive of metastatic disease. She opted for palliative radiotherapy for the primary thyroid cancer and made remarkable postoperative improvement. The authors conclude that surgical treatment of solitary metastatic lesion may produce good symptomatic relief irrespective of patient’s age and primary pathology, while emphasising the need for detailed clinical evaluation of patients with ‘red flag’ symptoms.

CEREBROSPINAL FLUID (CSF) CYTOLOGY: FACTORS IMPACTING ON DIAGNOSTIC YIELD

Background The identification of central nervous system (CNS) involvement by malignancies, using cytological analysis of CSF, is crucial for the appropriate treatment of patients.1 The aim of this study was to identify CSF specimen characteristics that have the highest diagnostic yield. Methods We conducted a retrospective review of all CSF specimens submitted for cytological analysis at Cork University Hospital from January 2010 to December 2011. Results 598 CSF samples were obtained from 390 people. The difference in volume between the diagnostic categories of equivocal (29%), inadequate (17%), positive (5%) and negative (48%) was found to be statistically significant, p-value <0.05 (kruskal-wallis test). Of the 66 (17%) requiring repeat CSF sampling 25% of initial samples were inadequate, falling to 10% on second sampling. The average volume of the initial samples was 2.72 ml, increasing to 3.93 ml on repeat sampling. Discussion Conventional cytology has shown high specificity but low sensitivity, being positive in 45% to 94% of initial specimens.1 Our study shows that factors increasing the likelihood of a definite result include a sample volume greater than 3 ml, and repeating sampling.

Clinical Reasoning: Vanishing tumor A 7-year puzzle solved

In 2005, a 60-year-old man presented to the hospital complaining of a 2-month history of headaches and lethargy. His medical history included osteoarthritis and hypertension. From a social perspective, he was married with children, drove a truck for a living, and had never traveled abroad. His family history was unremarkable. Investigations included a brain CT, which highlighted an enhancing, space-occupying lesion in the left basal ganglia with associated edema and mass effect (figure, A). He was prescribed high-dose dexamethasone while awaiting a neurosurgical review. One week later, a prebiopsy, contrast-enhanced CT showed a reduction in the size of the caudate head mass (figure, B). MRI brain with gadolinium showed small white matter changes and no mass was evident. He did not proceed to biopsy and was subsequently observed. CSF analysis was abnormal, revealing mature, lymphoid cells and some larger immature cells, some of which appeared plasmacytoid (B cell). Although suspicious for lymphoma, this result was nondiagnostic. The CSF protein level was 331. CSF low-density lipoprotein, Epstein-Barr virus, and flow cytometry were not performed. The β2-microglobulin level and serum low-density lipoprotein were normal. Serology for cytomegalovirus and toxoplasma were negative, as were ELISA for Toxocara and HIV screen. Slit-lamp examination was unremarkable. He was discharged, but readmitted 2 weeks later with a deep vein thrombosis. Repeat CSF cytology was again nondiagnostic. CSF was not examined for oligoclonal bands or myelin basic protein. A bone marrow biopsy and staging CT had normal results. Whole body PET/CT was unavailable.