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Papers by thomas laurence

PubMed, 2009

Background: Patients with chronic kidney disease (CKD) are at higher risk for stroke because of h... more Background: Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher prevalence of traditional and non-traditional cardiovascular risk factors. Methods: We performed an extensive literature review with pre-defined keywords. We summarized the results of the studies evaluating for risk factors predisposing to stroke in CKD patients. Results: The incidence of stroke and stroke-related mortality is higher in CKD patients compared with the general population. Presence of anemia, hypoalbuminemia, malnutrition, uremia, and hyperhomocysteinemia in patients with CKD is associated with higher incidence of stroke. Hemodialysis and renal transplant patients are at higher risk of developing stroke compared with those who do not require renal replacement therapy. Conclusion: The early recognition of risk factors associated with stroke in CKD population is imperative. Early interventions may potentially decrease the incidence and associated mortality of stroke in CKD patients.

Pacing and Clinical Electrophysiology, Nov 29, 2011

Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in t... more Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in the United States, especially those with chronic, uncontrolled epilepsy. Several pathophysiological events contributing to SUDEP include cardiac arrhythmias, respiratory dysfunction, and dysregulation of systemic or cerebral circulation. There is a significant body of literature suggesting the prominent role of cardiac arrhythmias in the pathogenesis of SUDEP. There is evidence to say that long-standing epilepsy can cause physiological and anatomical autonomic instability resulting in life-threatening arrhythmias. Tachyarrhythmias, bradyarrhythmias, and asystole are commonly seen during ictal, interictal, and postictal phase in epilepsy patients. It is unclear if these rhythm disturbances need attention as some of them may be just benign findings. Evidence regarding prolonged cardiovascular monitoring or the benefit of pacemaker/defibrillator implantation for primary or secondary prevention in epilepsy patients is limited. Awareness regarding pathophysiology, cardiac effects, and management options of SUDEP will become useful in guiding more individualized treatment in the near future.

Oncology Letters, 2011

Ewing's sarcoma is the second most common primary sacral tumor. Ewing's sarcomas are rare, aggres... more Ewing's sarcoma is the second most common primary sacral tumor. Ewing's sarcomas are rare, aggressive tumors with a tendency towards recurrence following resection and early metastasis. Although peak incidences are between the ages of 10 and 20 years, patients of younger or older age account for almost 30% of the cases. We report the case of a 52-year-old healthy female who presented with a 2-week history of pain in her right posterior thigh that was unable to be relieved by non-steroidal anti-inflammatory medicine and physical therapy. Magnetic resonance imaging demonstrated an irregular right presacral mass and core needle biopsy revealed a small, round blue cell neoplasm. Staging workup was normal and an open biopsy was positive for the ES translocation (22q12). The patient was treated with 17 cycles of vincristine, adriamycin and cytoxan with mesna rescue, alternating with ifosfamide and etoposide in addition to external beam radiation. Post-treatment imaging demonstrated complete resolution of the tumor. Six weeks post-treatment the patient presented with a recurrent tumor. This case emphasizes the importance of timely establishment of initial diagnosis, early metastasis in treatment responsive patients and under-utilization of positron emission tomography-computed tomography (PET-CT) during the treatment to detect sub-clinical metastasis.

Journal of vascular and interventional neurology, 2009

Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher preval... more Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher prevalence of traditional and non-traditional cardiovascular risk factors. We performed an extensive literature review with pre-defined keywords. We summarized the results of the studies evaluating for risk factors predisposing to stroke in CKD patients. The incidence of stroke and stroke-related mortality is higher in CKD patients compared with the general population. Presence of anemia, hypoalbuminemia, malnutrition, uremia, and hyperhomocysteinemia in patients with CKD is associated with higher incidence of stroke. Hemodialysis and renal transplant patients are at higher risk of developing stroke compared with those who do not require renal replacement therapy. The early recognition of risk factors associated with stroke in CKD population is imperative. Early interventions may potentially decrease the incidence and associated mortality of stroke in CKD patients.

International Journal of Radiation Oncology*Biology*Physics, 2002

ABSTRACT

Pacing and Clinical Electrophysiology, 2011

Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in t... more Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in the United States, especially those with chronic, uncontrolled epilepsy. Several pathophysiological events contributing to SUDEP include cardiac arrhythmias, respiratory dysfunction, and dysregulation of systemic or cerebral circulation. There is a significant body of literature suggesting the prominent role of cardiac arrhythmias in the pathogenesis of SUDEP. There is evidence to say that long‐standing epilepsy can cause physiological and anatomical autonomic instability resulting in life‐threatening arrhythmias. Tachyarrhythmias, bradyarrhythmias, and asystole are commonly seen during ictal, interictal, and postictal phase in epilepsy patients. It is unclear if these rhythm disturbances need attention as some of them may be just benign findings. Evidence regarding prolonged cardiovascular monitoring or the benefit of pacemaker/defibrillator implantation for primary or secondary preventi...

The Endocrinologist, 2008

Hypothyroidism is one of the most common sequelae of Sheehan syndrome. Patients affected by this ... more Hypothyroidism is one of the most common sequelae of Sheehan syndrome. Patients affected by this condition usually present with symptoms within weeks to months, but may present several years after postpartum hemorrhage. Rarely, the duration to onset of disease beyond 30 years has been reported in the literature. A 78-year-old woman presented with the complaint of fatigue for 2 months. Her physical examination was unremarkable. She was diagnosed with depression and started on fluoxetine. She returned to the clinic 3 weeks later with no improvement in her symptoms. Laboratory work revealed a normal thyroid stimulating hormone with a low free T4 and a low total T4. Additional investigations showed low serum follicle stimulating hormone, luteinizing hormone, and cortisol levels. Adrenocorticotropic hormone stimulation test was normal. A magnetic resonance imaging of the brain revealed a partially empty sella. On further questioning, the patient revealed that at the age of 27, after the delivery of her last child, she remained amenorrhic and failed to lactate. She recalled having excessive bleeding that required multiple blood transfusions. Based on her clinical presentation and history, she was diagnosed with delayed onset central hypothyroidism secondary to Sheehan syndrome and started on thyroid hormone supplement. As illustrated above, Sheehan syndrome can present several years postpartum. Appropriate history taking and relevant diagnostic workup is necessary to diagnose the condition.

Archives of physical medicine and rehabilitation, 1978

This electromyographic study was undertaken to assess the peripheral nervous system in patients w... more This electromyographic study was undertaken to assess the peripheral nervous system in patients with various types of paraplegia. Twelve patients were studied. In 8 patients the paraplegia was of the spastic type while 4 had flaccid paraplegia. Electromyographic abnormalities consisting of denervation potentials, slowed conduction and inexcitability of nerve were demonstrated in the lower limbs of all patients. These findings suggest a diffuse neuropathy of unknown cause, although local pressure palsies may have occurred in some patients. Because this involvement was more apparent in the flaccid group of paraplegic patients as compared with the spastic one, it is concluded that the peripheral nervous system plays an important role in determining the type of paraplegia that develops following complete spinal cord lesions.

The Journal of emergency medicine, 2016

Synthetic cannabinoids are swiftly gaining popularity and have earned a reputation of being relat... more Synthetic cannabinoids are swiftly gaining popularity and have earned a reputation of being relatively safer than other illicit drugs. However, there is a growing body of literature associating thromboembolic events with their use. A 32-year-old woman presented on four separate occasions with a new thromboemoblic event after smoking synthetic cannabinoids. She had no medical history, and over the span of 9 months she developed two kidney infarcts, pulmonary emboli, and an ischemic stroke. Each of these events occurred within 24 hours of smoking synthetic cannabinoids. During periods of abstinence, she remained free of thrombotic events. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This report shows that an association between thrombosis and the use of synthetic cannabinoids is reproducible and involves both venous and arterial thrombosis, suggesting activation of coagulation or inflammatory pathways. As the popularity of this drug continues to grow, we can expect to see a gr...

PubMed, 2009

Background: Patients with chronic kidney disease (CKD) are at higher risk for stroke because of h... more Background: Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher prevalence of traditional and non-traditional cardiovascular risk factors. Methods: We performed an extensive literature review with pre-defined keywords. We summarized the results of the studies evaluating for risk factors predisposing to stroke in CKD patients. Results: The incidence of stroke and stroke-related mortality is higher in CKD patients compared with the general population. Presence of anemia, hypoalbuminemia, malnutrition, uremia, and hyperhomocysteinemia in patients with CKD is associated with higher incidence of stroke. Hemodialysis and renal transplant patients are at higher risk of developing stroke compared with those who do not require renal replacement therapy. Conclusion: The early recognition of risk factors associated with stroke in CKD population is imperative. Early interventions may potentially decrease the incidence and associated mortality of stroke in CKD patients.

Pacing and Clinical Electrophysiology, Nov 29, 2011

Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in t... more Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in the United States, especially those with chronic, uncontrolled epilepsy. Several pathophysiological events contributing to SUDEP include cardiac arrhythmias, respiratory dysfunction, and dysregulation of systemic or cerebral circulation. There is a significant body of literature suggesting the prominent role of cardiac arrhythmias in the pathogenesis of SUDEP. There is evidence to say that long-standing epilepsy can cause physiological and anatomical autonomic instability resulting in life-threatening arrhythmias. Tachyarrhythmias, bradyarrhythmias, and asystole are commonly seen during ictal, interictal, and postictal phase in epilepsy patients. It is unclear if these rhythm disturbances need attention as some of them may be just benign findings. Evidence regarding prolonged cardiovascular monitoring or the benefit of pacemaker/defibrillator implantation for primary or secondary prevention in epilepsy patients is limited. Awareness regarding pathophysiology, cardiac effects, and management options of SUDEP will become useful in guiding more individualized treatment in the near future.

Oncology Letters, 2011

Ewing's sarcoma is the second most common primary sacral tumor. Ewing's sarcomas are rare, aggres... more Ewing's sarcoma is the second most common primary sacral tumor. Ewing's sarcomas are rare, aggressive tumors with a tendency towards recurrence following resection and early metastasis. Although peak incidences are between the ages of 10 and 20 years, patients of younger or older age account for almost 30% of the cases. We report the case of a 52-year-old healthy female who presented with a 2-week history of pain in her right posterior thigh that was unable to be relieved by non-steroidal anti-inflammatory medicine and physical therapy. Magnetic resonance imaging demonstrated an irregular right presacral mass and core needle biopsy revealed a small, round blue cell neoplasm. Staging workup was normal and an open biopsy was positive for the ES translocation (22q12). The patient was treated with 17 cycles of vincristine, adriamycin and cytoxan with mesna rescue, alternating with ifosfamide and etoposide in addition to external beam radiation. Post-treatment imaging demonstrated complete resolution of the tumor. Six weeks post-treatment the patient presented with a recurrent tumor. This case emphasizes the importance of timely establishment of initial diagnosis, early metastasis in treatment responsive patients and under-utilization of positron emission tomography-computed tomography (PET-CT) during the treatment to detect sub-clinical metastasis.

Journal of vascular and interventional neurology, 2009

Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher preval... more Patients with chronic kidney disease (CKD) are at higher risk for stroke because of higher prevalence of traditional and non-traditional cardiovascular risk factors. We performed an extensive literature review with pre-defined keywords. We summarized the results of the studies evaluating for risk factors predisposing to stroke in CKD patients. The incidence of stroke and stroke-related mortality is higher in CKD patients compared with the general population. Presence of anemia, hypoalbuminemia, malnutrition, uremia, and hyperhomocysteinemia in patients with CKD is associated with higher incidence of stroke. Hemodialysis and renal transplant patients are at higher risk of developing stroke compared with those who do not require renal replacement therapy. The early recognition of risk factors associated with stroke in CKD population is imperative. Early interventions may potentially decrease the incidence and associated mortality of stroke in CKD patients.

International Journal of Radiation Oncology*Biology*Physics, 2002

ABSTRACT

Pacing and Clinical Electrophysiology, 2011

Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in t... more Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in the United States, especially those with chronic, uncontrolled epilepsy. Several pathophysiological events contributing to SUDEP include cardiac arrhythmias, respiratory dysfunction, and dysregulation of systemic or cerebral circulation. There is a significant body of literature suggesting the prominent role of cardiac arrhythmias in the pathogenesis of SUDEP. There is evidence to say that long‐standing epilepsy can cause physiological and anatomical autonomic instability resulting in life‐threatening arrhythmias. Tachyarrhythmias, bradyarrhythmias, and asystole are commonly seen during ictal, interictal, and postictal phase in epilepsy patients. It is unclear if these rhythm disturbances need attention as some of them may be just benign findings. Evidence regarding prolonged cardiovascular monitoring or the benefit of pacemaker/defibrillator implantation for primary or secondary preventi...

The Endocrinologist, 2008

Hypothyroidism is one of the most common sequelae of Sheehan syndrome. Patients affected by this ... more Hypothyroidism is one of the most common sequelae of Sheehan syndrome. Patients affected by this condition usually present with symptoms within weeks to months, but may present several years after postpartum hemorrhage. Rarely, the duration to onset of disease beyond 30 years has been reported in the literature. A 78-year-old woman presented with the complaint of fatigue for 2 months. Her physical examination was unremarkable. She was diagnosed with depression and started on fluoxetine. She returned to the clinic 3 weeks later with no improvement in her symptoms. Laboratory work revealed a normal thyroid stimulating hormone with a low free T4 and a low total T4. Additional investigations showed low serum follicle stimulating hormone, luteinizing hormone, and cortisol levels. Adrenocorticotropic hormone stimulation test was normal. A magnetic resonance imaging of the brain revealed a partially empty sella. On further questioning, the patient revealed that at the age of 27, after the delivery of her last child, she remained amenorrhic and failed to lactate. She recalled having excessive bleeding that required multiple blood transfusions. Based on her clinical presentation and history, she was diagnosed with delayed onset central hypothyroidism secondary to Sheehan syndrome and started on thyroid hormone supplement. As illustrated above, Sheehan syndrome can present several years postpartum. Appropriate history taking and relevant diagnostic workup is necessary to diagnose the condition.

Archives of physical medicine and rehabilitation, 1978

This electromyographic study was undertaken to assess the peripheral nervous system in patients w... more This electromyographic study was undertaken to assess the peripheral nervous system in patients with various types of paraplegia. Twelve patients were studied. In 8 patients the paraplegia was of the spastic type while 4 had flaccid paraplegia. Electromyographic abnormalities consisting of denervation potentials, slowed conduction and inexcitability of nerve were demonstrated in the lower limbs of all patients. These findings suggest a diffuse neuropathy of unknown cause, although local pressure palsies may have occurred in some patients. Because this involvement was more apparent in the flaccid group of paraplegic patients as compared with the spastic one, it is concluded that the peripheral nervous system plays an important role in determining the type of paraplegia that develops following complete spinal cord lesions.

The Journal of emergency medicine, 2016

Synthetic cannabinoids are swiftly gaining popularity and have earned a reputation of being relat... more Synthetic cannabinoids are swiftly gaining popularity and have earned a reputation of being relatively safer than other illicit drugs. However, there is a growing body of literature associating thromboembolic events with their use. A 32-year-old woman presented on four separate occasions with a new thromboemoblic event after smoking synthetic cannabinoids. She had no medical history, and over the span of 9 months she developed two kidney infarcts, pulmonary emboli, and an ischemic stroke. Each of these events occurred within 24 hours of smoking synthetic cannabinoids. During periods of abstinence, she remained free of thrombotic events. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This report shows that an association between thrombosis and the use of synthetic cannabinoids is reproducible and involves both venous and arterial thrombosis, suggesting activation of coagulation or inflammatory pathways. As the popularity of this drug continues to grow, we can expect to see a gr...