You are called to evaluate a 64-year-old man who is 3 days into his postoperative course from a heart transplant. The patient’s spouse is at bedside and describes 2 minutes of seizurelike activity, followed by persistent confusion. Vital signs are unremarkable, and a neurologic examination reveals left hemianopsia but otherwise no focal deficits. Reviews of basic laboratory studies from the day are also unremarkable. Magnetic resonance imaging (MRI) of the brain is obtained and resulted below:
Which of the following is the most likely diagnosis?
Correct Answer: B
Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder that presents with a range of signs and symptoms that are reversible in nature. Nevertheless, intensive care monitoring and treatment are commonly required because of dreaded complications such as intracranial hypertension, cerebral hemorrhage, ischemia, or status epilepticus. Diagnosis is aided by the characteristic finding of vasogenic edema on neuroimaging. Frequently, this is a symmetric distribution in the parieto-occipital regions of the brain, as seen in the fluid-attenuated inversion recovery (FLAIR) sequence in the question.
PRES more commonly presents in the setting of hypertensive emergency; however, in 30% of cases, the BP is normal or only slightly elevated. Exogenic toxins can precipitate endothelial dysfunction predisposing to the syndrome. Immunosuppressive medications in the setting of solid organ transplantation and calcineurin inhibitors such as tacrolimus have been implicated in the development of PRES. Hypomagnesemia (A) is commonly seen in PRES; however, it is not likely to have precipitated this patient’s event given normal labs. Although his presentation could be consistent with subarachnoid hemorrhage (C), the MRI does not support this diagnosis. Progressive multifocal leukoencephalopathy (D) is a rare syndrome caused by the JC virus in an immunocompromised patient, where MRI may reveal diffuse areas of white matter demyelination. This would be a less likely etiology in the immediate postoperative period. Finally, viral encephalitis (E) can also produce demyelinating lesions on MRI that are localized to different areas of the brain depending on viral etiology with herpes simplex virus (HSV) classically involving the temporal lobe. However, the clinical scenario does not suggest a viral prodrome or infectious presentation.
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A 42-year-old woman is transferred to the intensive care unit (ICU) from the floor. The primary team was concerned about deteriorating mental status and the potential for loss of airway protection. Her records show that she was admitted two days prior with diffuse abdominal swelling. Computed tomography (CT) demonstrated ascites, as well as an ovarian mass concerning for malignancy. On initial examination, she is visibly irritable but appropriately responsive to voice.
Vital signs:
Further history obtained from her husband reveals a 2-week history of hallucinations and lip smacking leading up to admission. She takes only sertraline for depression.
Which of the following are the most appropriate next step in management?
Correct Answer: D
Anti-NMDAR (NMDA receptor) encephalitis is the most common form of autoimmune encephalitis. It typically presents as a paraneoplastic syndrome with psychotic features including behavioral changes such as agitation, hallucinations, delusions, and catatonia. Patients can also develop abnormal movements of the face and limbs, speech and memory problems, reduced level of consciousness, and autonomic instability. Antibodies are formed against the glutamate NR1 subunit of NMDAR. The association with ovarian teratoma is strong with 58% of affected young women having the diagnosis. Antibodies can be detected in the cerebrospinal fluid (CSF) to make the diagnosis. Initial therapy includes systemic glucocorticoids, intravenous immunoglobulin, and plasma exchange.
Ultimate therapy for this patient would be removal of the tumor. Although transthoracic echocardiogram would be indicated before starting doxorubicin (A) due to concerns of developing cardiomyopathy, this would not be an acute solution for a patient with psychosis. The ascites here is most likely secondary to the malignant process and not hepatic in origin (B), thus eliminating lactulose as a great treatment option. She does demonstrate features of tardive dyskinesia; however, a selective serotonin reuptake inhibitor (SSRI) such as sertraline would not contribute to this. Treatment with haloperidol (C) would likely further exacerbate symptoms of tardive dyskinesia.
A 32-year-old man presents to the ICU after coiling of the anterior communicating artery aneurysm for subarachnoid hemorrhage. He is placed on cefazolin for external ventricular drain prophylaxis. On the sixth postoperative day he develops frequent loose stools and a temperature of 38.8°C.
Which of the following is INCORRECT regarding fever?
Correct Answer: A
Early administration of acetaminophen to treat fever due to probable infection does not affect the number of ICU-free days. A study published in 2015 by Young et al randomized febrile ICU patients with known or suspected infection to receive 1 g intravenous acetaminophen or placebo every 6 hours until discharge, fever resolution, antibiotic discontinuation, or death. Primary outcome was ICU-free days from randomization to day 28. There was no significant difference between groups. Despite this, there is evidence to support that early treatment of fever leads to reduction of vasopressor dose and reduced mortality in septic patients requiring mechanical ventilation.
Fever has many pathophysiologic effects including increased oxygen consumption (D), enhanced immune function, increased antimicrobial activity, and decreased pathogen growth (B). Older adults have a lower baseline temperature and impaired ability to develop fever (C). Acetaminophen is the mainstay of therapy and works by inhibiting cyclooxygenase. The oxidized form is active in the brain after metabolization by the p450 system (E).
A 50-year-old man was involved in a motorcycle accident over July 4th weekend. He received cardiopulmonary resuscitation (CPR) on the scene until arrival of emergency medical services, with return of spontaneous circulation in transit to the hospital. He underwent decompressive craniectomy and subdural hematoma evacuation for which he has been recovering in the intensive care unit for 2 weeks. He remains intubated and under continuous electroencephalography (EEG) monitoring. Despite being off sedative medications, he has yet to regain consciousness. The neurologist consulted is leaving for vacation and asks you to perform an examination and document an assessment for coma today. The patient intermittently opens his eyes, moves bilateral upper extremities without purpose, and has a strong cough and gag reflex. EEG demonstrates delta waves with no evidence of sleep patterns.
The table below outlines key features and differences in the stages of recovery from coma and general anesthesia:
This patient demonstrates brainstem reflexes and EEG activity inconsistent with brain death (C). The presence of eye movements eliminates general anesthesia and coma (A, B). Although he is intubated, we cannot infer about ventilator dependence based on the information provided. The presence of nonpurposeful movements, coupled with the absence of sleep-wake activity on EEG, eliminates minimally conscious state as a diagnosis (E). This clinical picture is most consistent with vegetative state.
A 71-year-old woman presents with a 2-week history of progressive numbness, tingling, and weakness in bilateral lower extremities. An MRI is obtained and reveals the findings below:
Which of the following regarding diagnosis and treatment of this lesion is TRUE?
Spinal metastases frequently occur in cancer and compression of the spinal cord can occur when tumor extends into the epidural space. Diagnosis is confirmed by imaging, and MRI with gadolinium is the gold standard modality with up to 100% sensitivity in detection of cord compression. When contrast is not used, tumor may still be detected (D). For patients who cannot undergo MRI, CT myelography is the next best option. Compression occurs in the thoracic, lumbar, and cervical segments in 60%, 25%, and 15% of cases, respectively (E).
Treatment of malignant cord compression is directed toward palliation and cure. Glucocorticoids have been demonstrated to reduce neurologic impairment and pain (A). Radiotherapy is a good option for hematologic tumors such as lymphoma and myeloma which are characteristically radiosensitive. On the contrary, non–small-cell lung cancer and renal, thyroid, and gastrointestinal cancers, as well as sarcoma and melanoma, are relatively radioresistant and are generally treated with surgery (B). Radiotherapy is not an effective treatment for spinal instability, thus surgical correction should be pursued (C).
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