Hooman Oktaei - Academia.edu (original) (raw)

Papers by Hooman Oktaei

Research paper thumbnail of A case of dual secreting adrenal neoplasm consistent with pheochromocytoma and cushing syndrome

˜The œAmerican journal of the medical sciences, Feb 1, 2024

Research paper thumbnail of THU577 Acth Dependent Cushing Syndrome Identification And Management Challenges

Journal of the Endocrine Society, Sep 30, 2023

Research paper thumbnail of Pheochromocytoma Diagnosed During First Trimester of Pregnancy

JCEM case reports, Feb 23, 2024

Research paper thumbnail of Lithium-associated primary hyperparathyroidism

Research paper thumbnail of The Effect of Chronic Hyperinsulinemia on Fibrous Tissue of Ventricular Myocardium in Nontransplant Model of Chronic Hyperinsulinemic Dogs

Journal of Investigative Medicine, 2001

Research paper thumbnail of 50 the Effect of Chronic Hyperinsulinemia on Fibrous Tissue of Ventricular Myocardium in Nontransplant Model of Chronic Hyperinsulinemic Dogs

Journal of Investigative Medicine, 2004

Research paper thumbnail of Thyrotoxic Hypokalemic Periodic Paralysis in An African American Male

Journal of Investigative Medicine, 2005

Research paper thumbnail of ODP136 A Rare Case of Necrotizing Myopathy after Statin Use

Journal of the Endocrine Society, Nov 1, 2022

Introduction: Statin associated necrotizing autoimmune myopathy is an extremely rare side effects... more Introduction: Statin associated necrotizing autoimmune myopathy is an extremely rare side effects of stain use. The incidence is approximately 2-3/100,000 Patients treated with statins. It usually associated with significant proximal muscle weakness, strikingly elevated creatine kinase (CK) levels and persistent symptoms despitestatin discontinuation. Here, we present a case with necrotizing myopathy after statin use as a reminder to clinicians for appropriately suspicious of this phenomenon while on treatment of statins. Clinical case: A 35 year old male with a past medical history of Autism, Type 2 Diabetes Mellitus, Hyperlipidemia, and Hypertension was brought to emergency room for right leg pain. Family states he had difficulty walking for a few weeks and had a fall from couch a week ago. Initial Vitals showed HR at 134 bpm, temp 35.9, BP 157/85 mmHg, RR 19 breaths/min. Labs showed Creatinine. 3.29 mg/dL, CO2 24 mmol/L, Na 141 mmol/L, K 4.2 mmol/L, Ca 9.5 mg/dL, glucose 265 mg/dL, AST/

Research paper thumbnail of ODP078 An Unsolved Mystery of Hyperparathyroidism for 12 Years

Journal of the Endocrine Society, Nov 1, 2022

Research paper thumbnail of PSAT042 Adrenal Insufficiency Associated to Immune Checkpoint Inhibitors

Journal of the Endocrine Society, Nov 1, 2022

Research paper thumbnail of 390 the Effect of Chronic Hyperinsulinemia on Coronary Arteries in Nontransplant Dog Model

Journal of Investigative Medicine, 2005

Introduction Hyperinsulinemia has been implicated as a possible contributing factor for increased... more Introduction Hyperinsulinemia has been implicated as a possible contributing factor for increased cardiovascular risk, abnormal lipid and carbohydrate metabolism and smooth muscle cell proliferation. However, a direct causal relationship between insulin per se in hyperinsulinemic states and these factors has not been established. Objectives The objectives of this study were 1) to develop a model of endogenous hyperinsulinemia without the use of pharmacological agents and 2) to determine the effect of hyperinsulinemia as an independent risk factor on development of coronary artery atherosclerosis. Research Design and Methods We established hyperinsulinemia in eight dogs (group 1) by using a novel surgical technique in which endocrine secretions were diverted from the portal to systemic circulation by end to side anastomosis of the splenic and superior pancreaticoduodenal veins to the inferior vena cava. Another eight dogs served as sham operated control (group 2). Results Presurgical baseline plasma insulin levels were not different in the two groups (5.6 μU/mL in experimental group versus 8.4 μU/mL in control), but did differ at 3 months (26.1 μU/mL in experimental group versus 6.0 μU/mL in control group, p < .001). This difference remained significant at six months (24.4 μU/mL in experimental group versus 6.1 μU/mL in control group, p < .001), and in six years (12.58 ± 4.6 μU/mL in experimental group versus 6.05 ± 1.3 μU/mL in control group, p = .005). There was a significant difference in C peptide level in the two groups (0.53 ± 0.17 ng/mL in hyperinsulinemic versus 0.32 ± 0.12 ng/mL in nonhyperinsulinemic, p = .015) at the end of six years. There was no significant difference in the level of glucose, total cholesterol, triglycerides, HDL and FFA at the end of follow-up. Coronary arteries of 6 hyperinsulinemic dogs and 4 nonhyperinsulinemic dogs at the end were available for study. Based on the reading of a pathologist who was masked to the identity of experimental versus control, there was fibrosis in muscularis mucosa of 2 out of 6 hyperinsulinemic dogs but none in four nonhyperinsulinemic dogs. Conclusions We conclude that hyperinsulinemia per se in dogs is associated with 33% increased risk of fibrosis in muscularis mucosa of coronary arteries, despite the lack of significant differences in lipid profile.

Research paper thumbnail of 109 Thyrotoxic Hypokalemic Periodic Paralysis in an African American Male

Journal of Investigative Medicine, 2005

Background: Alendronate has been widely used in the treatment of patient with osteoporosis; sever... more Background: Alendronate has been widely used in the treatment of patient with osteoporosis; several studies have demonstrated the long-term efficacy and safety of alendronate (Fosamax) in patient with osteoporosis. Secondary hyperparathyroidism has been described in patient with chronic renal failure due to stimulation of parathyroid cells by stimuli such as hyperphosphatemia, hypocalcemia and calcitriol deficiency, leading to parathyroid gland hyperplasia. Case Report: We describe a patient who developed secondary hyperparathyroidism despite elevated levels of vitamin D, and normal renal function, while on alendronate, vitamin D and calcium for severe osteoporosis. In August 1998 a 43 year old female was referred to our endocrine clinic for severe osteoporosis. She was found to have normal PTH, serum calcium, phosphorus, urinary calcium excretion, and creatinine clearance. Her 25-hydroxyvitamin D [25-(OH)vitD] level was 16.4 ng/mL. She was started on alendronate 70 mg/w, vitamin D 50,000 IU/w, and calcium 2 g/d. She responded well to this treatment with improvement in her bone mineral density and vitamin D level. In June 2002 she developed secondary hyperparathyroidism, (PTH = 176 pg/mL, calcium of 8.8 mg/dL, normal ionized calcium, 25(OH)vitD = 45.1 ng/mL, 24 h urinary calcium = 240 mg/d). The patient eventually underwent neck exploration in 2004, during which 3 1/5 hyperplastic parathyroid glands were excised. Subsequently the PTH level returned to normal. Discussion: Secondary hyperparathyroidism has classically been described in patients with renal failure or severe vitamin D deficiency due to constant stimulation of parathyroid cells by hyperphosphatemia, hypocalcemia and calcitriol deficiency, leading to parathyroid gland hyperplasia. Skeletal resistance to the calcemic action of PTH is another factor that appears to contribute to the genesis of secondary hyperparathyroidism in chronic renal failure. Recently several studies have demonstrated that alendronate impairs the ability of PTH to increase bone mineral density in osteoporotic patients, possibly by reducing the impact of PTH on bone formation. The present case demonstrates the occurrence of parathyroid hyperplasia and secondary hyperparathyroidism, despite absence of conventional etiologic factors. We propose the possibility of long-term alendronate therapy and skeletal resistance to the effect of PTH as a mechanism of hyperparathyroidism in this patient.

Research paper thumbnail of Abstract #1502833: Dilemma Identifying Pseudohypercalcemia

Research paper thumbnail of Genome-wide association analysis identifies ancestry-specific genetic variation associated with acute response to metformin and glipizide in SUGAR-MGH

Research paper thumbnail of The Effect of Chronic Hyperinsulinemia on Coronary Arteries in Nontransplant Dog Model

Journal of Investigative Medicine

Research paper thumbnail of Abstract #1405991: Graves’ Disease Presenting as Thymic Hyperplasia

Research paper thumbnail of Acute destructive hyperparathyroiditis presenting with severe hypercalcemia: a novel association of COVID-19 infection

The American Journal of the Medical Sciences

Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on ... more Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre-including this research content-immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

Research paper thumbnail of Identification of genetic variation influencing metformin response in a multi-ancestry genome-wide association study in the Diabetes Prevention Program (DPP)

Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have no... more Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have not replicated in the Diabetes Prevention Program (DPP). To assess pharmacogenetic interactions in pre-diabetes, we conducted a genome-wide association study (GWAS) in the DPP. Cox proportional hazards models tested associations with diabetes incidence in metformin (MET, n=876) and placebo (PBO, n=887) arms. Multiple linear regression assessed association with one-year change in metformin-related quantitative traits, adjusted for baseline trait, age, sex, and 10 ancestry principal components. We tested for gene-by-treatment interaction. No significant associations emerged for diabetes incidence. We identified four genome-wide significant variants after correcting for correlated traits (p<9×10-9). In MET, rs144322333 near ENOSF1 (minor allele frequency [MAF]AFR=0.07, MAFEUR=0.002) was associated with an increase in % glycated hemoglobin (per minor allele β=0.39 [95% CI 0.28, 0.50], p=2.8...

Research paper thumbnail of Association of Metformin With the Development of Age-Related Macular Degeneration

JAMA Ophthalmology

ImportanceAge-related macular degeneration (AMD) is a leading cause of blindness with no treatmen... more ImportanceAge-related macular degeneration (AMD) is a leading cause of blindness with no treatment available for early stages. Retrospective studies have shown an association between metformin and reduced risk of AMD.ObjectiveTo investigate the association between metformin use and age-related macular degeneration (AMD).Design, Setting, and ParticipantsThe Diabetes Prevention Program Outcomes Study is a cross-sectional follow-up phase of a large multicenter randomized clinical trial, Diabetes Prevention Program (1996-2001), to investigate the association of treatment with metformin or an intensive lifestyle modification vs placebo with preventing the onset of type 2 diabetes in a population at high risk for developing diabetes. Participants with retinal imaging at a follow-up visit 16 years posttrial (2017-2019) were included. Analysis took place between October 2019 and May 2022.InterventionsParticipants were randomly distributed between 3 interventional arms: lifestyle, metformin,...

Research paper thumbnail of ODP078 An Unsolved Mystery of Hyperparathyroidism for 12 Years

Journal of the Endocrine Society

Introduction Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and elevated or... more Introduction Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and elevated or inappropriately normal levels of parathyroid hormone (PTH). It results from excessive secretion of PTH from one or more of the parathyroid glands. The number and location of the parathyroid glands can be variable. The organogenesis of the parathyroids determines the definitive location in adulthood. We hereby present an interesting case of primary hyperparathyroidism caused by the ectopic parathyroid gland. Clinical case 85-year-old Black female with papillary thyroid cancer status post total thyroidectomy and RAI in 2011, hypertension, hyperlipidemia, osteoporosis, long standing PHPT referred to ER for hypercalcemia from a physician's office. A review of the system was significant for unintentional 40 lb. weight loss over the past several months and increased urinary frequency. She denied confusion, abdominal pain, constipation, paresthesia. On physical exam she was afebrile, BP 14...

Research paper thumbnail of A case of dual secreting adrenal neoplasm consistent with pheochromocytoma and cushing syndrome

˜The œAmerican journal of the medical sciences, Feb 1, 2024

Research paper thumbnail of THU577 Acth Dependent Cushing Syndrome Identification And Management Challenges

Journal of the Endocrine Society, Sep 30, 2023

Research paper thumbnail of Pheochromocytoma Diagnosed During First Trimester of Pregnancy

JCEM case reports, Feb 23, 2024

Research paper thumbnail of Lithium-associated primary hyperparathyroidism

Research paper thumbnail of The Effect of Chronic Hyperinsulinemia on Fibrous Tissue of Ventricular Myocardium in Nontransplant Model of Chronic Hyperinsulinemic Dogs

Journal of Investigative Medicine, 2001

Research paper thumbnail of 50 the Effect of Chronic Hyperinsulinemia on Fibrous Tissue of Ventricular Myocardium in Nontransplant Model of Chronic Hyperinsulinemic Dogs

Journal of Investigative Medicine, 2004

Research paper thumbnail of Thyrotoxic Hypokalemic Periodic Paralysis in An African American Male

Journal of Investigative Medicine, 2005

Research paper thumbnail of ODP136 A Rare Case of Necrotizing Myopathy after Statin Use

Journal of the Endocrine Society, Nov 1, 2022

Introduction: Statin associated necrotizing autoimmune myopathy is an extremely rare side effects... more Introduction: Statin associated necrotizing autoimmune myopathy is an extremely rare side effects of stain use. The incidence is approximately 2-3/100,000 Patients treated with statins. It usually associated with significant proximal muscle weakness, strikingly elevated creatine kinase (CK) levels and persistent symptoms despitestatin discontinuation. Here, we present a case with necrotizing myopathy after statin use as a reminder to clinicians for appropriately suspicious of this phenomenon while on treatment of statins. Clinical case: A 35 year old male with a past medical history of Autism, Type 2 Diabetes Mellitus, Hyperlipidemia, and Hypertension was brought to emergency room for right leg pain. Family states he had difficulty walking for a few weeks and had a fall from couch a week ago. Initial Vitals showed HR at 134 bpm, temp 35.9, BP 157/85 mmHg, RR 19 breaths/min. Labs showed Creatinine. 3.29 mg/dL, CO2 24 mmol/L, Na 141 mmol/L, K 4.2 mmol/L, Ca 9.5 mg/dL, glucose 265 mg/dL, AST/

Research paper thumbnail of ODP078 An Unsolved Mystery of Hyperparathyroidism for 12 Years

Journal of the Endocrine Society, Nov 1, 2022

Research paper thumbnail of PSAT042 Adrenal Insufficiency Associated to Immune Checkpoint Inhibitors

Journal of the Endocrine Society, Nov 1, 2022

Research paper thumbnail of 390 the Effect of Chronic Hyperinsulinemia on Coronary Arteries in Nontransplant Dog Model

Journal of Investigative Medicine, 2005

Introduction Hyperinsulinemia has been implicated as a possible contributing factor for increased... more Introduction Hyperinsulinemia has been implicated as a possible contributing factor for increased cardiovascular risk, abnormal lipid and carbohydrate metabolism and smooth muscle cell proliferation. However, a direct causal relationship between insulin per se in hyperinsulinemic states and these factors has not been established. Objectives The objectives of this study were 1) to develop a model of endogenous hyperinsulinemia without the use of pharmacological agents and 2) to determine the effect of hyperinsulinemia as an independent risk factor on development of coronary artery atherosclerosis. Research Design and Methods We established hyperinsulinemia in eight dogs (group 1) by using a novel surgical technique in which endocrine secretions were diverted from the portal to systemic circulation by end to side anastomosis of the splenic and superior pancreaticoduodenal veins to the inferior vena cava. Another eight dogs served as sham operated control (group 2). Results Presurgical baseline plasma insulin levels were not different in the two groups (5.6 μU/mL in experimental group versus 8.4 μU/mL in control), but did differ at 3 months (26.1 μU/mL in experimental group versus 6.0 μU/mL in control group, p < .001). This difference remained significant at six months (24.4 μU/mL in experimental group versus 6.1 μU/mL in control group, p < .001), and in six years (12.58 ± 4.6 μU/mL in experimental group versus 6.05 ± 1.3 μU/mL in control group, p = .005). There was a significant difference in C peptide level in the two groups (0.53 ± 0.17 ng/mL in hyperinsulinemic versus 0.32 ± 0.12 ng/mL in nonhyperinsulinemic, p = .015) at the end of six years. There was no significant difference in the level of glucose, total cholesterol, triglycerides, HDL and FFA at the end of follow-up. Coronary arteries of 6 hyperinsulinemic dogs and 4 nonhyperinsulinemic dogs at the end were available for study. Based on the reading of a pathologist who was masked to the identity of experimental versus control, there was fibrosis in muscularis mucosa of 2 out of 6 hyperinsulinemic dogs but none in four nonhyperinsulinemic dogs. Conclusions We conclude that hyperinsulinemia per se in dogs is associated with 33% increased risk of fibrosis in muscularis mucosa of coronary arteries, despite the lack of significant differences in lipid profile.

Research paper thumbnail of 109 Thyrotoxic Hypokalemic Periodic Paralysis in an African American Male

Journal of Investigative Medicine, 2005

Background: Alendronate has been widely used in the treatment of patient with osteoporosis; sever... more Background: Alendronate has been widely used in the treatment of patient with osteoporosis; several studies have demonstrated the long-term efficacy and safety of alendronate (Fosamax) in patient with osteoporosis. Secondary hyperparathyroidism has been described in patient with chronic renal failure due to stimulation of parathyroid cells by stimuli such as hyperphosphatemia, hypocalcemia and calcitriol deficiency, leading to parathyroid gland hyperplasia. Case Report: We describe a patient who developed secondary hyperparathyroidism despite elevated levels of vitamin D, and normal renal function, while on alendronate, vitamin D and calcium for severe osteoporosis. In August 1998 a 43 year old female was referred to our endocrine clinic for severe osteoporosis. She was found to have normal PTH, serum calcium, phosphorus, urinary calcium excretion, and creatinine clearance. Her 25-hydroxyvitamin D [25-(OH)vitD] level was 16.4 ng/mL. She was started on alendronate 70 mg/w, vitamin D 50,000 IU/w, and calcium 2 g/d. She responded well to this treatment with improvement in her bone mineral density and vitamin D level. In June 2002 she developed secondary hyperparathyroidism, (PTH = 176 pg/mL, calcium of 8.8 mg/dL, normal ionized calcium, 25(OH)vitD = 45.1 ng/mL, 24 h urinary calcium = 240 mg/d). The patient eventually underwent neck exploration in 2004, during which 3 1/5 hyperplastic parathyroid glands were excised. Subsequently the PTH level returned to normal. Discussion: Secondary hyperparathyroidism has classically been described in patients with renal failure or severe vitamin D deficiency due to constant stimulation of parathyroid cells by hyperphosphatemia, hypocalcemia and calcitriol deficiency, leading to parathyroid gland hyperplasia. Skeletal resistance to the calcemic action of PTH is another factor that appears to contribute to the genesis of secondary hyperparathyroidism in chronic renal failure. Recently several studies have demonstrated that alendronate impairs the ability of PTH to increase bone mineral density in osteoporotic patients, possibly by reducing the impact of PTH on bone formation. The present case demonstrates the occurrence of parathyroid hyperplasia and secondary hyperparathyroidism, despite absence of conventional etiologic factors. We propose the possibility of long-term alendronate therapy and skeletal resistance to the effect of PTH as a mechanism of hyperparathyroidism in this patient.

Research paper thumbnail of Abstract #1502833: Dilemma Identifying Pseudohypercalcemia

Research paper thumbnail of Genome-wide association analysis identifies ancestry-specific genetic variation associated with acute response to metformin and glipizide in SUGAR-MGH

Research paper thumbnail of The Effect of Chronic Hyperinsulinemia on Coronary Arteries in Nontransplant Dog Model

Journal of Investigative Medicine

Research paper thumbnail of Abstract #1405991: Graves’ Disease Presenting as Thymic Hyperplasia

Research paper thumbnail of Acute destructive hyperparathyroiditis presenting with severe hypercalcemia: a novel association of COVID-19 infection

The American Journal of the Medical Sciences

Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on ... more Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre-including this research content-immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

Research paper thumbnail of Identification of genetic variation influencing metformin response in a multi-ancestry genome-wide association study in the Diabetes Prevention Program (DPP)

Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have no... more Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have not replicated in the Diabetes Prevention Program (DPP). To assess pharmacogenetic interactions in pre-diabetes, we conducted a genome-wide association study (GWAS) in the DPP. Cox proportional hazards models tested associations with diabetes incidence in metformin (MET, n=876) and placebo (PBO, n=887) arms. Multiple linear regression assessed association with one-year change in metformin-related quantitative traits, adjusted for baseline trait, age, sex, and 10 ancestry principal components. We tested for gene-by-treatment interaction. No significant associations emerged for diabetes incidence. We identified four genome-wide significant variants after correcting for correlated traits (p<9×10-9). In MET, rs144322333 near ENOSF1 (minor allele frequency [MAF]AFR=0.07, MAFEUR=0.002) was associated with an increase in % glycated hemoglobin (per minor allele β=0.39 [95% CI 0.28, 0.50], p=2.8...

Research paper thumbnail of Association of Metformin With the Development of Age-Related Macular Degeneration

JAMA Ophthalmology

ImportanceAge-related macular degeneration (AMD) is a leading cause of blindness with no treatmen... more ImportanceAge-related macular degeneration (AMD) is a leading cause of blindness with no treatment available for early stages. Retrospective studies have shown an association between metformin and reduced risk of AMD.ObjectiveTo investigate the association between metformin use and age-related macular degeneration (AMD).Design, Setting, and ParticipantsThe Diabetes Prevention Program Outcomes Study is a cross-sectional follow-up phase of a large multicenter randomized clinical trial, Diabetes Prevention Program (1996-2001), to investigate the association of treatment with metformin or an intensive lifestyle modification vs placebo with preventing the onset of type 2 diabetes in a population at high risk for developing diabetes. Participants with retinal imaging at a follow-up visit 16 years posttrial (2017-2019) were included. Analysis took place between October 2019 and May 2022.InterventionsParticipants were randomly distributed between 3 interventional arms: lifestyle, metformin,...

Research paper thumbnail of ODP078 An Unsolved Mystery of Hyperparathyroidism for 12 Years

Journal of the Endocrine Society

Introduction Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and elevated or... more Introduction Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and elevated or inappropriately normal levels of parathyroid hormone (PTH). It results from excessive secretion of PTH from one or more of the parathyroid glands. The number and location of the parathyroid glands can be variable. The organogenesis of the parathyroids determines the definitive location in adulthood. We hereby present an interesting case of primary hyperparathyroidism caused by the ectopic parathyroid gland. Clinical case 85-year-old Black female with papillary thyroid cancer status post total thyroidectomy and RAI in 2011, hypertension, hyperlipidemia, osteoporosis, long standing PHPT referred to ER for hypercalcemia from a physician's office. A review of the system was significant for unintentional 40 lb. weight loss over the past several months and increased urinary frequency. She denied confusion, abdominal pain, constipation, paresthesia. On physical exam she was afebrile, BP 14...