A 25-month-old male with a history of mild reactive airway disease and sickle cell trait was noted by his mother to be breathing slowly and erratically 2 h after being laid down for a nap. Emergency medical services were called and paramedics encountered a pulseless, apneic patient. Cardiopulmonary resuscitation was immediately initiated. Return of spontaneous circulation was achieved in the ambulance on route to our institution’s emergency department.\nOn arrival, physical examination revealed an afebrile toddler, unresponsive to voice or noxious stimulation with agonal respirations, a blood oxygen saturation of 93% with bag-mask-assisted ventilation, and a blood pressure of 99/65 mmHg (mean arterial pressure 76 mmHg). Neurologic examination demonstrated 3 mm, non-reactive pupils and global hyperreflexia. Orotracheal intubation was performed emergently. Initial laboratory evaluation revealed normal electrolytes (Na+ 138 mEq/L, K+ 4.9 mEq/L, Cl− 104 mEq/L, Ionized Ca2+ 5.2 mEq/L), leukocyte count (11,100/mm3), venous blood gases (pH 7.37, PvCO2 44, PvO2 47, 25.7), and serum lactate (0.9 mmol/L). Upon further interrogation, the patient’s mother reported the presence of prescription opiates (extended release morphine) in the household, which she uses for pain control secondary to frequent sickle cell anemia crises. A total of two doses of naloxone (0.1 mg/kg i.v. push each) were administered, after which the patient regained pupillary reactivity and began moving all four extremities spontaneously. A urine toxicology panel was obtained, which was positive for morphine.\nA non-contrast head CT was obtained (Figure B), which revealed acute hydrocephalus and extensive, symmetric bilateral cerebellar hemispheric hypoattenuation consistent with severe cerebellar edema that resulted in compression of the fourth ventricle and displacement of the midbrain and pons superiorly. Cervicomedullary junction compression secondary to cerebellar tonsillar herniation was also noted. Neurosurgery was consulted and the patient was emergently taken to the operating room for the placement of an external ventricular drain, suboccipital craniectomy, and a C1 laminectomy. A significant portion of the edematous and ischemic cerebellar hemispheres and tonsils were resected bilaterally, thereby decompressing the posterior fossa and cervicomedullary junction.\nA brain MRI obtained on postoperative day 1 demonstrated cerebellar and cervicomedullary junction decompression, with extensive restricted diffusion in the remaining cerebellar parenchyma (Figure B). Multifocal areas of diffusion restriction were also noted bilaterally in the anterior cerebral artery-middle cerebral artery and middle cerebral artery-posterior cerebral artery watershed territories involving portions of the frontal, occipital, and temporal lobe white matter. An MRA/MR venogram demonstrated no craniocervical or intracranial arterial abnormalities or evidence of cortical or dural venous sinus thrombosis. The patient was extubated on postoperative day 5. Assessment at postoperative day 18 demonstrated an easily arousable child, with spontaneous eye opening, equally round and reactive pupils, and with purposeful movements of all four extremities.\nOutpatient follow-up at 29 months of age (3 months after presentation) demonstrated an active child speaking in full sentences. He was able to ambulate independently, albeit with a slightly widened base of support, and mild left lower extremity spasticity which did not limit his ability to climb or descend stairs with rail support.
A 41-year-old woman presented to the emergency room of another hospital with recent confusion and impaired balance. She had been using cocaine daily for seven months. MRI FLAIR images showed multiple white matter signal changes in both cerebral hemispheres in a predominantly periventricular distribution (Fig. –) sparing the corpus callosum, cerebellum and brainstem. Restricted diffusion was present in many lesions (not shown). Subtle gadolinium enhancement was present in a few lesions (not shown). She was treated with supportive care for one week and then discharged with partial recovery. She resumed cocaine use and was then admitted to our centre six weeks after the previous hospital discharge because of worsening neurological symptoms. She was completely bedridden with inability to walk, incontinence, severely impaired communication skills, behavioural problems, cognitive impairment, and multifocal neurological deficits. MRI FLAIR images showed marked progression compared to the previous study. Confluent white matter abnormalities involved both cerebral hemispheres (Fig. –). There was subtle scattered restricted diffusion and no gadolinium enhancement. Urine testing was positive for cocaine, oxycodone, opiates, benzodiazepines, tramadol and citalopram, and negative for cannabinoids, amphetamine and methadone. Other investigations included the following normal or negative results: complete blood count, electrolytes, glucose, liver enzymes, thyroid stimulating hormone, T3, T4, creatinine kinase, angiotensin converting enzyme, HIV, Hepatitis A, B, and C screens, Lyme serology, syphilis screen, blood screen for salicylates, acetaminophen and ethanol. The serum creatinine was elevated (137 micromoles/l) as was the urea (7.6 millimoles/l). Serum albumin was low (29 g/l). The erythrocyte sedimentation rate ranged from 22 to 64 on multiple samplings, C-reactive protein was elevated at 11 mg/l while antinuclear antibodies, pANCA, cANCA, C3, C4, NMDA receptor and anti-thyroid peroxidase antibodies were normal. The vitamin B12 level was low at 166 picomole/l (normal >180). Copper, zinc and ceruloplasmin levels were normal. CSF protein was slightly elevated at 0.48 g/l. The glucose, chloride and cell count (4 × 106/l) were normal. No CSF acid fast bacilli were seen and cultures for bacteria and fungi were negative. CSF PCR for CMV and HSV1–2 were negative. She was treated with intravenous methylprednisolone, 1000 mg/day for five days, and plasma exchange. She showed substantial, albeit partial, recovery soon thereafter which continued over the course of several months. At four months follow-up multiple domains of cognitive function were improved but she had some residual deficits in attention, calculation, and visuospatial function. She was independent with respect to walking and most activities of daily living. Follow-up MRI at that time showed improvement of the subcortical and periventricular signal abnormalities and no new lesions. Similarly, no new lesions were seen on MRI 13 months after presentation (not shown).