Brain Pathology Case of the Month - July 2014

Contributed by Walter Struhal1 MD, Milan R. Vosko1 MD, PhD, Monika Mitterhumer,2MD, Gerhard Syre2 Prof. MD, Dieter Zeiner3 MD, Daniel Floery4 MD, Franz Fellner4 Prof. MD, Gerhard Ransmayr1 Prof. MD, Franz Gruber1 MD
1 Department of Neurology, Allgemeines Krankenhaus der Stadt Linz, Linz, Austria
2 Department of Pathology, Allgemeines Krankenhaus der Stadt Linz, Linz, Austria
3 Department of Neurology, Krankenhaus Amstetten, Amstetten, Austria
4 Institute of Radiology, Allgemeines Krankenhaus der Stadt Linz, Linz, Austria


CLINICAL HISTORY

A 70 year old former farmer and cattle breeder was admitted to a district hospital due to intermittent confusion, neuropsy-chological slowing with otherwise unremarkable neurological examination. His family first noticed personality changes after a right knee arthroscopy two weeks earlier.

Meningoencephalitis was suspected, spinal tab revealed a cell count of 74 cells/ÁL with increased protein (419mg/dl). He developed transient febrile temperatures to 38░ Celsius. Cell count decreased under therapy with Ceftriaxone and Sultamicillin (7 days later: 16 cells), several days later Standacillin was added to cover for a possible Listeria meningitis. After initial improvement of intermittent confusional states he deteriorated developing generalized myoclonic twitches and brain stem signs with somnolence, left sided ptosis, swallowing difficulties and tetraparesis. EEG showed an inconsistent left frontotemporal local lesion at admission. EEG changes progressed subsequently to a generalized diffusely slow record. 500mg/d Levetiracetam was added to treat suspected complex focal seizures. MRI showed white matter micro vascular lesions but was otherwise unremarkable. A tine test was negative.

He was then transmitted to the neurological intensive care unit of our hospital. At this stage, he required mechanical ventilation. The control brain contrast-enhanced T1-weighted MRI images revealed pronounced contrast enhancement of leptomeningeal structures, particularly at the skull base and brainstem (transversal and sagittal orientation - Figs 1, 2 and 3). A non-contrast-enhanced CT of the thorax showed a calcified small mediastinal lymph node and was otherwise unremarkable (Fig. 4). Spinal tap was repeated and after 21 days microbiology CSF cultures grew a pathogen.

The patient developed hydrocephalus and external ventricle drainage was placed. Despite stabilization of ventricular pressure and specific therapy, brain stem encephalitis progressed with development of opsoclonus, recurrent spontaneous nystagmus and coma. All weaning attempts were unsuccessful and the patient died 4 months after his first symptoms had developed.

MICROSCOPIC PATHOLOGY

Microscopic workup showed diffuse infiltration of meningeal tissue with lymphocytes, plasma cells few neutrophile granulo-cytes and infiltration of brain stem and frontobasal cortex with lymphocytes. Figs. 5, 6, and 7 show HE staining of brainstem tissue revealing granulation tissue with poorly formed granulomata and multinucleated giant cells of Langhans type. There was also a paratracheal lymph node with reactive lymph node tissue and necrotic granuloma (Fig 8).

FINAL DIAGNOSIS


International Society of Neuropathology