December 2001: Rapidly progressive motor weakness, starting in pregnancy

Cases of the Month, October–December 2001 The October Case of the Month (COM). A 40‐year‐old Xhosa male presented with progressive upper lumbar back pain and weakness At examination he was emaciated and had enlarged lymph nodes in the groin and axilla. Both lower limbs were severely atrophic and weak. Sensation to touch and pain was decreased below L3 bilaterally. MR of the spine showed a discrete, contrast‐enhancing epidural mass. A T10–T12 laminectomy revealed an soft, vascular extradural tumor dorsal to the cord. The mass was loosely applied to the dura and easy to remove. The operative specimen consisted of a sausage‐shaped (3.5×2.0×1.2 cm), thinly‐encapsulated mass of reddish‐brown tissue. The cut surface had a mottled, vaguely nodular, yellowlsh‐brown appearance. Microscopic examination revealed sheets of hematopoeitic elements, including myeloid, red cell and megakaryocytic lines, the latter showing Factor 8‐related positivity. The final diagnosis was extramedullary hematopoiesis (EMH). A bone marrow biopsy performed as a result of the diagnosis showed a myeloproliferative disease and polycythemia vera. EMH in the spinal epidural space is a rare but treatable cause of progressive paraparesis in patients with a variety of hematological disorders. Since 1956 there have been more than 50 reported cases, most of which occurred in association with thalassaemia. In spinal cord compression secondary to EMH, the lesions are commonly localized to the mid‐lower thoracic region. The November COM. A 67‐year‐old man was found to have massive pituitary necrosis occupying approximately 85% of the anterior lobe after being supported with mechanical ventilation for 35 days. The findings were compatible with “respirator pituitary” found In mechanically ventilated patients. The lesions represent coagulative infarctions due to ischemia. The role of the respirator is believed to be buying time to allow the changes to develop. The December COM. A 25‐year‐old woman presented with rapidly progressive motor weakness necessitating ventilation 10 months after the onset. Despite immunosuppressive therapy she died 27 months later, without developing significant extramotor features. Autopsy revealed evidence of both upper and lower motor neuron loss with wide‐spread motor and extramotor intraneuronal basophilic inclusions, most of which did not show ubiquitin immunoreactivity. Motor neuron disease with basophilic inclusions appears to be a rare, but distinctive pathological subtype, with most reported cases occurring sporadically in young women and having a rapid clinical progression.