Brain Pathology Case of the Month - July 2014

Contributed by Alejandra González-Duarte* MD, PhD, Juan Pablor Venzor-Castellanos* MD, Irene Treviño-Frenk* MD, Fernando Cano-García, MD**, Ariadna Barrios-Ordoñez**
Departments of *Neurology, **Pathology and ***Radiology of the Insitituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City


A 20 year-old male complaining of headache, photophobia and altered mental status arrived to the ER from another hospital. His symptoms began a few months earlier with diarrhea and vomiting, daily fever up to 39ºC, and weight loss. At that time, the neurological examination showed a Glasgow Coma Scale (GCS) score of 8 points and nuchal rigidity. A brain CT scan was normal, and ceftriaxone 2gr per day, vancomycin 2 gr every 12 hours, ampicillin 2gr every 4 hours, clarithromycin 500mg every 12 hours, and acyclovir 800 mg every 5 hours were started. Because there was no improvement, two days later he was transferred to our hospital. At entry the heart rate was 53 beats per minute, breathing rate was 18 per minute with Cheyne-Stokes respiration, blood pressure was 100/60 mmHg, and temperature was 38ºC. The GCS score was of 6 points: 2 points for the ocular response, 1 point for the verbal response and 3 points for the motor the response. His head and gaze were persistently deviated to the right. He had bilateral papilledema, and his pupils were asymmetric, with the right pupil size of 2mm and the left of 5mm. Strength was abated, but when pain was elicited he acquired a posture of decerebration. The Hoffman and Babinski signs were produced on the right side. He had involuntary myoclonic jerks in the upper and lower extremities that lasted more than 5 minutes. Nuchal rigidity was present. He was intubated and put on mechanical ventilation. Dexamethasone was administrated for cerebral edema, levetiracetam and propofol for persistent epileptic seizures. Amphotericin B was added and the antibiotics were continued. Two days later mannitol, meropenem, rifampicin, pyrazinamide and etambutol were included, however, the patient continued to be hypothermic and had severe slow heart rate and hypotension. He died 9 days later.


CBC showed a total blood count of 7000 cells/mm3 (neutrophils of 87%, lymphocytes of 7.95% and monocytes of 4.8%), hemoglobin of 15.4 gr/dL and platelets of 124,000 cells/mm3. Serum glucose was 101 mg/dL, creatinine was 0.9 mg/L and sodium was 134 mg/dL. The rest of the laboratory studies including liver function tests were normal. An ELISA for HIV was negative.

A brain MRI showed enlargement of the ventricles with transependymal migration of CSF surrounding the ventricles symptomatic of acute hydrocephalus, effacement of surci due to cerebral edema, bilateral extensive hyperintense images in the basal ganglia and surrounding parenchyma in the DWI suggesting ischemic lesions in both territories of the middle cerebral artery (MCA) (Figures 1, 2, 3, and 4), and generalized dense leptomeningeal enhancement and arachnoiditis in the post-contrast T1-weighted images. An angioMRI showed a severely injured left MCA (Figure 5).

A lumbar puncture was performed with an opening pressure of 22 cmH20, and the CSF showed a pH of 7.47, glucose of 52mm/dL, proteins of 111 mg/dL, and WBC of 32cells/mm3. Adenosine deaminase enzyme (ADA) in CSF was 9UI. CSF PCR for M. tuberculosis, CMV, VSH and VHZ were negative, as well as the cryptococcus and pneumococcus antigen, and the CSF IgG for toxoplasmosis. A transcranial Doppler ultrasound demonstrated bilateral high velocities of the middle and anterior cerebral arteries suggestive of vasospasm. The EEG showed generalized theta rhythm.


The total brain weight was 1450g. An extensive green dense exudate was found in the basal subarachnoid cisterns of the brain (Figure 6). Cerebral edema was found and both amygdala were displaced downward. In contrast to what was shown in the MRI, only one infarct was found at the left thalamus (Figure 7). Microscopically, the brain had features of acute purulent meningitis, which were more prominent on the basal surface of the cerebrum, consisting of areas of inflammatory infiltrate composed of lymphocytes and plasmatic cells outspread with epithelioid histiocytes, alternated with extensive areas of necrosis (Figure 8). Neither caseous necrosis nor the characteristic multinucleated Langhans cells were observed. The Ziehl-Neelsen acid-fast stain is shown in Figure 9. This prompted a PAS stain to rule-out MAC complex, which was negative. The lumen of the MCA branches was clear, and there were no inflammatory infiltrates in any other vessel. What is your diagnosis?


International Society of Neuropathology