Identifying cause of PRES in a patient with sepsis and chronic anemia requiring blood transfusion.
Poster #: 046
Session/Time: A
Author:
Alexandra Crawford, BS, MS
Mentor:
Timothy Chiang, MD
Research Type: Case Report
Abstract
INTRODUCTION:
Posterior Reversible Encephalopathy Syndrome (PRES) is a rare condition with debated pathophysiology. The leading theories include a hyper-perfusion model, where elevated, fluctuating arterial pressures cause disruption in the blood brain barrier leading to vasogenic edema in a preferential parieto-occipital distribution. However, roughly 30% of cases of PRES have been in normotensive patients where it is theorized that circulating toxins, either endogenous (from septic response) or exogenous (such as chemotherapeutics), lead to direct endothelial dysfunction and resultant edema. Given a wide range of possible radiographic and clinical manifestations, PRES is a challenging diagnosis requiring better characterization.
MAIN BODY:
A 39-year-old female with a history of polysubstance use, anemia, and chronic extremity wounds presented with fever and limb swelling. Her initial labs were significant for anemia and leukopenia for which she received 1 unit of packed red blood cells. She was started on broad spectrum antibiotics due to concern for sepsis. Further workup revealed sacroiliac joint osteomyelitis confirmed by IR-guided joint aspiration. Her hospital course was complicated by seizure-like activity prompting an EEG which showed focal neuronal dysfunction in the right posterior quadrant. Subsequent MRI head revealed bilateral cerebral cortical/subcortical hyperintensities and patchy irregularities in the cerebellum on T2/FLAIR imaging. Considering the neurological and radiographic findings, her presentation was most consistent with PRES. She was discharged on long term antibiotics and levetiracetam maintenance therapy with a favorable prognosis.
DISCUSSION/CLINICAL FINDINGS:
PRES is a rare diagnosis with unclear pathophysiology making diagnosis and prevention challenging. Two leading theories attempt to explain the vasogenic edema seen in PRES. One theory is that fluctuations in blood pressure overcome the posterior circulation autoregulation. The other instead theorizes there is direct cytotoxic damage to the endothelium. In this septic patient who was largely normotensive, the latter theory seems more explanatory. She also required a blood transfusion due to anemia, further increasing the risk of mounting a systemic immune response from donor immunoglobulins or cytokines. Few cases have also theorized an association between blood transfusions and PRES. This patient's presentation supports the direct cytotoxic damage theory of PRES and brings up the potential of multiple risk factors compounding together to lead to unique or atypical cases.
CONCLUSION:
Currently, there is a lack of understanding of PRES and its exact pathophysiology. Leading theories have prompted certain measures in care, such as controlling blood pressure and preventing large fluctuations. However, as in this patient, PRES can still present in patients with other primary conditions such as sepsis and anemia, giving support to alternative theories in its pathophysiology. It is worth considering in this patient if the combination of anemia and systemic inflammation led to a hemodynamic state pre-disposing her to PRES. Further collection of cases of PRES may offer commonalities that can aid in understanding its pathophysiology with the goal of faster diagnosis and prevention.
Posterior Reversible Encephalopathy Syndrome (PRES) is a rare condition with debated pathophysiology. The leading theories include a hyper-perfusion model, where elevated, fluctuating arterial pressures cause disruption in the blood brain barrier leading to vasogenic edema in a preferential parieto-occipital distribution. However, roughly 30% of cases of PRES have been in normotensive patients where it is theorized that circulating toxins, either endogenous (from septic response) or exogenous (such as chemotherapeutics), lead to direct endothelial dysfunction and resultant edema. Given a wide range of possible radiographic and clinical manifestations, PRES is a challenging diagnosis requiring better characterization.
MAIN BODY:
A 39-year-old female with a history of polysubstance use, anemia, and chronic extremity wounds presented with fever and limb swelling. Her initial labs were significant for anemia and leukopenia for which she received 1 unit of packed red blood cells. She was started on broad spectrum antibiotics due to concern for sepsis. Further workup revealed sacroiliac joint osteomyelitis confirmed by IR-guided joint aspiration. Her hospital course was complicated by seizure-like activity prompting an EEG which showed focal neuronal dysfunction in the right posterior quadrant. Subsequent MRI head revealed bilateral cerebral cortical/subcortical hyperintensities and patchy irregularities in the cerebellum on T2/FLAIR imaging. Considering the neurological and radiographic findings, her presentation was most consistent with PRES. She was discharged on long term antibiotics and levetiracetam maintenance therapy with a favorable prognosis.
DISCUSSION/CLINICAL FINDINGS:
PRES is a rare diagnosis with unclear pathophysiology making diagnosis and prevention challenging. Two leading theories attempt to explain the vasogenic edema seen in PRES. One theory is that fluctuations in blood pressure overcome the posterior circulation autoregulation. The other instead theorizes there is direct cytotoxic damage to the endothelium. In this septic patient who was largely normotensive, the latter theory seems more explanatory. She also required a blood transfusion due to anemia, further increasing the risk of mounting a systemic immune response from donor immunoglobulins or cytokines. Few cases have also theorized an association between blood transfusions and PRES. This patient's presentation supports the direct cytotoxic damage theory of PRES and brings up the potential of multiple risk factors compounding together to lead to unique or atypical cases.
CONCLUSION:
Currently, there is a lack of understanding of PRES and its exact pathophysiology. Leading theories have prompted certain measures in care, such as controlling blood pressure and preventing large fluctuations. However, as in this patient, PRES can still present in patients with other primary conditions such as sepsis and anemia, giving support to alternative theories in its pathophysiology. It is worth considering in this patient if the combination of anemia and systemic inflammation led to a hemodynamic state pre-disposing her to PRES. Further collection of cases of PRES may offer commonalities that can aid in understanding its pathophysiology with the goal of faster diagnosis and prevention.