Incidence of postoperative hyponatremia after endoscopic endonasal pituitary transposition for skull base pathologies.

PURPOSE: Pituitary transposition is a novel surgical approach to access the retroinfundibular space and interpeduncular cistern. Few studies have evaluated post-surgical outcomes, including incidence of hyponatremia, following pituitary transposition. METHODS: This is a retrospective study including 72 patients who underwent endoscopic endonasal surgery involving pituitary transposition for non-pituitary derived tumors over a decade at the University of Pittsburgh Medical Center. Anterior pituitary deficiencies and replacement therapy, tumor pathology and pre-operative serum sodium (Na) were recorded. Na was assessed at postoperative day 1, 3, 5, 7, and 10. Anatomical/surgical parameters included sellar height, sellar access angle to approach the tumor, and cranial extension of the tumor above the sellar floor (B) compared to the height of the gland (A) (B/A). T-test (normally distributed variables) and Wilcoxon rank-sum test (not-normally distributed) were applied for mean comparison. Logistic regression analyzed correlations between anatomical/surgical parameters and postoperative hyponatremia. RESULTS: 55.6% of patients developed post-operative transient hyponatremia. Two patients (5%) developed severe hyponatremia (sodium level < 120 mmol/L). Eleven (15.3%) patients required desmopressin replacement immediately post-operatively, and 2 other patients needed desmopressin after discharge and after sodium nadir developed. Hyponatremia was inversely associated with sellar access angle (p = 0.02) and the tumor cranial extension above the sellar floor showing a trend towards significance (p = 0.09). CONCLUSION: More than half of patients who had pituitary transposition developed transient hyponatremia. Hyponatremia was more common in those with narrower sellar access angle and smaller cranial extension of the tumor above the sellar floor. Anatomical/surgical parameters may allow risk-stratification for post-operative hyponatremia following pituitary transposition.

IGF-1 is positively associated with BMI in patients with acromegaly.

PURPOSE: Acromegaly is a disorder characterized by IGF-1 excess due to autonomous GH secretion. In individuals without acromegaly, IGF-1 is not only influenced by GH secretion but is also sensitive to other factors including nutritional status, as evidenced by the inverted U-shaped association between BMI and IGF-1; in low-weight individuals (BMI < 18.5 kg/m2) and those who are obese, IGF-1 levels may be frankly low. It is not known if this same relationship between BMI and IGF-1 is also observed in acromegaly. METHODS: Retrospective study including patients who underwent resection of a pituitary adenoma (n = 197) for either acromegaly (n = 32) or a nonfunctioning adenoma (NFPA, n = 165) at a large academic medical center between 1/1/2015 and 5/31/2021. RESULTS: Median BMI in acromegaly was 30.8 kg/m2 (range 20.9-42.6 kg/m2). Percent upper limit of normal (%ULN) IGF-1 was 228.2% [159.0, 271.4] in acromegaly versus 32.2% [18.5, 50] in NFPA (p < 0.0001). There was a significant positive association between BMI and %ULN IGF-1 (R = 0.35, p < 0.05) in acromegaly. In contrast, there was no association between BMI and %ULN IGF-1 in the NFPA group as a whole (p = 0.22), but a significant inverse association between BMI and %ULN IGF-1 in NFPA patients with a BMI ≥ 35 kg/m2 (rho = - 0.39, p = 0.02). CONCLUSION: In contrast to individuals without acromegaly, BMI is significantly and positively associated with IGF-1 in acromegaly across the weight spectrum. Future studies are needed to determine if obese patients with acromegaly experience more significant symptoms related to their disease, or if patients with a low BMI may require different diagnostic criteria.

Weight regain after total meal replacement very low-calorie diet program with and with-out anti-obesity medications.

Background: Very low-calorie diets (VLCDs) employing total meal replacement (TMR) offer substantial short-term weight loss. Concurrently, anti-obesity medications (AOMs) have shown promise as adjunctive treatments when combined with VLCDs. Aims: This study aimed to investigate the impact of adjuvant AOMs on weight loss and weight regain within a comprehensive lifestyle program. Methods: This is a retrospective study of patients with obesity enrolled in VLCD/TMR programs,  specifically the OPTIFAST program. Results: Data from 206 patients (68% women, mean age 52.39 ± 13.05 years, BMI 41.71 ± 7.04 kg/m2) were analyzed. Of these, 139 received no AOM (AOM-), while 67 received AOMs (AOM+). Total body weight loss percentages (TWL%) at 6 and 18 months were -17.87% ± 7.02 and -12.10% ± 11.56, respectively. There was no significant difference in 6-month weight loss between the AOM groups. However, the AOM + group exhibited lower weight regain (3.29 kg ± 10.19 vs. 7.61 kg ± 11.96; p = 0.006) and weight regain percentage (WR%) (31.5% ± 68.7 vs. 52.16% ± 64.4; p = 0.04) compared with the AOM- group. Conclusion: The findings highlighted the potential of AOMs and VLCD/TMR as effective strategies for long-term weight management in individuals with obesity.

Toward Optimized and Cost-Efficient Protocols for Inferior Petrosal Sinus Sampling in the Diagnosis of Cushing Disease.

BACKGROUND AND OBJECTIVE: Conventional protocols for inferior petrosal sinus sampling (IPSS) during the workup of hypercortisolemia require adrenocorticotrophic hormone (ACTH) measurement at multiple time points with corticotropic-releasing hormone (CRH) used as a stimulator. Modernized evidence-based protocols must also reflect the increased utilization of desmopressin (DDAVP) for ACTH stimulation as the manufacturing shortage of traditionally used CRH continues. We model the diagnostic accuracy and potential economic savings of DDAVP utilization and reduced time point sampling. METHODS: A single-institution, retrospective review of patients undergoing IPSS between 2007 and 2021 was performed. A computational search for the minimal set of time points which preserves conventional diagnostic accuracy was performed by testing all 1 through 5-point combinations generated using a binomial expansion. Economic savings were modeled using a publicly available hospital chargemaster. RESULTS: A total of 50 patients qualified for inclusion, 47 of whom were diagnosed with Cushing disease and 3 with ectopic Cushing syndrome. Single-point diagnostic accuracy for DDAVP-stimulated tests was 71.4%-92.9%, and seven 2-point combinations (5-25 procedural minutes) were found, which preserved conventional diagnostic accuracy. Single-point accuracy for CRH-stimulated tests was 67.9%-89.3%, and two 2-point combinations ( t = -15, t = +2 and t = -15, t = +10) preserved accuracy. For every time point removed, the cost of ACTH laboratory tests was reduced by $507 from $3042 for 6-point IPSS). The shortest and most economical stimulator and time point combination that preserved conventional accuracy was DDAVP sampling at t = 0 and t = +5 or t = +2 and t = +5 minutes, which cost $2028 total compared with the most expensive 6-point IPSS option with CRH ($6392). CONCLUSION: DDAVP is a cost-efficient and effective alternative to CRH during IPSS. Our results encourage prospective evaluation of potentially fewer sampling time points in the interest of time and cost efficiency balanced with preserved accuracy.

Major Genetic Motifs in Pituitary Adenomas: A Practical Literature Update.

BACKGROUND: The literature includes many studies examining the genetic abnormalities that influence pituitary adenomas (PAs). We aimed to state the collective knowledge on the genetic underpinnings of PAs by organizing, summarizing, and consolidating the literature to serve as a comprehensive review for scientists and clinicians of the most up-to-date information underlying the genetic landscape of PAs. METHODS: The PubMed and Google Scholar databases were searched using multiple key words and combined Medical Subject Headings terms; only articles published in English between January 2000 and January 2022 were included. Articles in which the focus did not relate to genetics, that included mainly anecdotal evidence, or that were single case studies were eliminated. RESULTS: PAs are one of the most common intracranial neoplasms. However, the genetic underpinnings for these tumors are not yet fully elucidated. There are several categories of PAs: clinically significant versus not clinically significant, functional versus nonfunctional, and germline-derived versus sporadic origin. Each of these disease subcategories is characterized by unique genetic aberrations. Recently, more genes and other types of genetic aberrations have been identified as possible causes of PAs, such as copy number variations and altered levels of microRNAs. CONCLUSIONS: This review serves to consolidate and summarize the literature discussing the genetic motifs of PAs to help physicians and scientists deliver patient-centered therapies.

Rapidly Progressive Pituitary Apoplexy in a Patient with COVID-19 Disease Treated with Endoscopic Endonasal Surgery.

This report describes a case of pituitary apoplexy with rapidly evolving hemorrhage in a 74-year-old female with coronavirus disease 2019 (COVID-19) disease. The patient presented with severe headache and mild respiratory symptoms, with laboratories concerning for pituitary hypofunction. Brain imaging demonstrated a sellar mass concerning for a pituitary adenoma with ischemic apoplexy. She subsequently developed visual deficits within 24 hours of presentation, and repeat imaging demonstrated evolving hemorrhage and new mass effect on the optic chiasm. She was successfully managed with urgent endoscopic endonasal surgery despite her COVID-19 positive status by taking special intraoperative precautions to mitigate SARS-CoV2 transmission risk. Only a handful of cases of pituitary apoplexy have been reported in association with COVID-19 disease, and even fewer reports exist of endonasal procedures in such cases. We discuss the potential implication of COVID-19 in the occurrence of pituitary apoplexy, in addition to the safety and success of endonasal surgery in this population.

Paraneoplastic Hypoglycemia Leading to Insulin Independence in a Patient With Type 1 Diabetes.

OBJECTIVE: Non-islet cell tumor hypoglycemia (NICTH) is an uncommon paraneoplastic syndrome associated with mesenchymal neoplasms such as gastrointestinal stromal tumors (GISTs). We report the case of a patient with type 1 diabetes (T1D) and recurrent GIST who not only required discontinuation of insulin therapy but also required continuous parenteral glucose infusions to prevent hypoglycemia. METHODS: A 59-year-old woman with a 24-year history of T1D and recurrent GIST presented with frequent episodes of symptomatic hypoglycemia despite continuous reductions in her insulin therapy. Laboratory workup revealed undetectable insulin and C-peptide, low insulin-like growth factor (IGF) 1, normal IGF-2, and an elevated IGF-2:IGF-1 ratio. Medical management with prednisone alone and, later, in combination with octreotide did not reduce hypoglycemic episodes. Eventually, during hospitalization for severe hypoglycemia, she was treated and discharged with continuous intravenous dextrose infusion. She ultimately required around-the-clock glucose infusions, which helped her maintain what she believed was an acceptable quality of life during her remaining weeks. DISCUSSION: NICTH is characterized by excessive tumor production of IGF-2 or pro-IGF-2, leading to unrestricted glucose uptake in peripheral tissues and hypoglycemia. A diagnosis of NICTH can be made on the basis of low IGF-1 levels in the plasma with normal or elevated IGF-2. Tumor resection is the most definitive treatment for NICTH. CONCLUSION: This patient with T1D presented with resistant hypoglycemia due to recurrence of an enlarging GIST. She required discontinuation of all insulin therapy and continuous dextrose infusions to maintain euglycemia.

Endogenous Glucose Production in Critical Illness.

Regulation of endogenous glucose production (EGP) by hormonal, neuronal, and metabolic signaling pathways contributes to the maintenance of euglycemia under normal physiologic conditions. EGP is defined by the generation of glucose from substrates through glycogenolysis and gluconeogenesis, usually in fasted states, for local and systemic use. Abnormal increases in EGP are noted in patients with diabetes mellitus type 2, and elevated EGP may also impact the pathogenesis of nonalcoholic fatty liver disease and congestive heart failure. In this narrative review, we performed a literature search in PubMed to identify recently published English language articles characterizing EGP in critical illness. Evidence from preclinical and clinical studies demonstrates that critical illness can disrupt EGP through multiple mechanisms including increased systemic inflammation, counterregulatory hormone and catecholamine release, alterations in the hypothalamic-pituitary axis, insulin resistance, lactic acidosis, and iatrogenic insults such as vasopressors and glucocorticoids administered as part of clinical care. EGP contributes to hyperglycemia in critical illness when abnormally elevated and to hypoglycemia when abnormally depressed, each of which has been independently associated with increased mortality. Increased EGP may also promote protein catabolism that could worsen critical illness myopathy and impede recovery. Better understanding of the mechanisms and factors contributing to dysregulated EGP in critical illness may help in the development of therapeutic strategies that promote euglycemia, reduce intensive care unit-associated catabolism, and improve patient outcomes.

Association of the systemic host immune response with acute hyperglycemia in mechanically ventilated septic patients.

Hyperglycemia during sepsis is associated with increased organ dysfunction and higher mortality. The role of the host immune response in development of hyperglycemia during sepsis remains unclear. We performed a retrospective analysis of critically ill adult septic patients requiring mechanical ventilation (n = 153) to study the relationship between hyperglycemia and ten markers of the host injury and immune response measured on the first day of ICU admission (baseline). We determined associations between each biomarker and: (1) glucose, insulin, and c-peptide levels at the time of biomarker collection by Pearson correlation; (2) average glucose and glycemic variability in the first two days of ICU admission by linear regression; and (3) occurrence of hyperglycemia (blood glucose>180mg/dL) by logistic regression. Results were adjusted for age, pre-existing diabetes mellitus, severity of illness, and total insulin and glucocorticoid dose. Baseline plasma levels of ST2 and procalcitonin were positively correlated with average blood glucose and glycemic variability in the first two days of ICU admission in unadjusted and adjusted analyses. Additionally, higher baseline ST2, IL-1ra, procalcitonin, and pentraxin-3 levels were associated with increased risk of hyperglycemia. Our results suggest associations between the host immune response and hyperglycemia in critically ill septic patients particularly implicating the interleukin-1 axis (IL-1ra), the interleukin-33 axis (ST2), and the host response to bacterial infections (procalcitonin, pentraxin-3).

Therapeutic Effects of Endogenous Incretin Hormones and Exogenous Incretin-Based Medications in Sepsis.

BACKGROUND: Sepsis, a complex disorder characterized by a dysregulated immune response to an inciting infection, affects over one million Americans annually. Dysglycemia during sepsis hospitalization confers increased risk of organ dysfunction and death, and novel targets for the treatment of sepsis and maintenance of glucose homeostasis are needed. Incretin hormones are secreted by enteroendocrine cells in response to enteral nutrients and potentiate insulin release from pancreatic ß cells in a glucose-dependent manner, thereby reducing the risk of insulin-induced hypoglycemia. Incretin hormones also reduce systemic inflammation in preclinical studies, but studies of incretins in the setting of sepsis are limited. METHODS: In this bench-to-bedside mini-review, we detail the evidence to support incretin hormones as a therapeutic target in patients with sepsis. We performed a PubMed search using the medical subject headings "incretins," "glucagon-like peptide-1," "gastric inhibitory peptide," "inflammation," and "sepsis." RESULTS: Incretin-based therapies decrease immune cell activation, inhibit proinflammatory cytokine release, and reduce organ dysfunction and mortality in preclinical models of sepsis. Several small clinical trials in critically ill patients have suggested potential benefit in glycemic control using exogenous incretin infusions, but these studies had limited power and were performed in mixed populations. Further clinical studies examining incretins specifically in septic populations are needed. CONCLUSIONS: Targeting the incretin hormone axis in sepsis may provide a means of not only promoting euglycemia in sepsis but also attenuating the proinflammatory response and improving clinical outcomes.

Intensive Blood Glucose Control and Vascular Outcomes in Patients with Type 2 Diabetes Mellitus.

People with type 2 diabetes mellitus are at high risk of morbidity and mortality from cardiovascular disease (CVD). Based on observed relationships between hyperglycemia and CVD, several large clinical trials have investigated the ability of treatment strategies to achieve hemoglobin A1c less than 7% (53 mmol/mol) as a way of reducing this risk. These studies demonstrate that intensified glycemic therapy may reduce CVD risk in younger patients with recent-onset type 2 diabetes mellitus but not in high-risk older individuals with established disease. Attention to blood pressure and lipid-lowering therapies with modified glycemic goals for older high-risk individuals is recommended.

Cardiovascular health knowledge and behavior in patient attendants at four tertiary care hospitals in Pakistan--a cause for concern.

BACKGROUND: Knowledge about coronary heart disease (CHD) and its risk factors is an important pre-requisite for an individual to implement behavioral changes leading towards CHD prevention. There is scant data on the status of knowledge about CHD in the general population of Pakistan. The objective of this study was to assess knowledge of CHD in a broad Pakistani population and identify the factors associated with knowledge. METHODS: Cross sectional study was carried out at four tertiary care hospitals in Pakistan using convenience sampling. Standard questionnaire was used to interview 792 patient attendants (persons accompanying patients). Knowledge was computed as a continuous variable based on correct answers to fifteen questions. Multivariable linear regression was conducted to determine the factors independently associated with knowledge. RESULTS: The mean age was 38.1 (+/- 13) years. 27.1% had received no formal education. The median knowledge score was 3.0 out of a possible maximum of 15. Only 14% were able to correctly describe CHD as a condition involving limitation in blood flow to the heart. Majority of respondents could identify only up to two risk factors for CHD. Most commonly identified risk factors were stress (43.4%), dietary fat (39.1%), smoking (31.9%) and lack of exercise (17.4%). About 20% were not able to identify even a single risk factor for CHD. Factors significantly associated with knowledge included age (p = 0.023), income (p < 0.001), education level (p < 0.001), residence (p < 0.001), a family history of CHD (p < 0.001) and a past history of diabetes (p = 0.004). Preventive practices were significantly lacking; 35%, 65.3% and 84.6% had never undergone assessment of blood pressure, glucose or cholesterol respectively. Only a minority felt that they would modify their diet, stop smoking or start exercising if a family member was to develop CHD. CONCLUSION: This is the first study assessing the state of CHD knowledge in a relatively diverse non-patient population in Pakistan. There are striking gaps in knowledge about CHD, its risk factors and symptoms. These translate to inadequate preventive behavior patterns. Educational programs are urgently required to improve the level of understanding of CHD in the Pakistani population.

A 23-year-old female with a mixed germ cell tumor of the pituitary infundibulum: the challenge of differentiating neoplasm from lymphocytic infundibuloneurohypophysitis-a case report and literature review.

The pathologic spectrum of diseases that infiltrate the pituitary infundibulum includes a broad variety of clinical entities. There are significant differences in the prevalence of these etiologies depending on the age of presentation. Lymphocytic infundibuloneurohypophysitis (LINH) predominates over other causes of infundibular disease in adults over age 21. Differentiating LINH from other causes of infundibular disease can be difficult because the various etiologies often have similar clinical presentations and radiologic imaging characteristics. We report the first case in an adult of a mixed germ cell tumor comprised of germinoma and embryonal cell carcinoma infiltrating the pituitary infundibulum. In our case, a 23-year-old female was initially misdiagnosed as having LINH. She presented with panhypopituitarism and diabetes insipidus, which is the most common initial presentation in both entities. The two diagnoses are difficult to distinguish based on MRI imaging, CSF findings, and histopathological examination. Our case demonstrates the need for close follow-up of patients with isolated lesions of the pituitary infundibulum and reinforces the need for biopsy of an infundibular lesion when progression of disease is demonstrated. In our case, biopsy with comprehensive immunohistochemical staining was the sole means of making a definitive diagnosis.

Complementary and Alternative Medicine: Perceptions of Medical Students from Pakistan.

BACKGROUND: In view of the increasing popularity of complementary and alternative medicine (CAM), it is imperative that medical students, the health professionals of tomorrow, possess adequate knowledge on the topic. OBJECTIVES: This is a descriptive study designed to assess the knowledge, attitudes and behavior of medical students about CAM and to capture their perceptions and opinions about its integration into the medical curriculum. METHODS: A questionnaire-based cross-sectional survey was done on 198 medical students selected randomly from a Pakistani medical college. Associations between different variables were tested using the χ2-test of significance. RESULTS: Among the 198 participants, a majority believed that some of the CAM modalities are useful; they lacked knowledge, however, about their safety and efficacy. Most of the students believed that it should be used in conjunction with conventional medicine and that, if given adequate training, they would incorporate it in their future medical practice. One-third of the respondents voted in favor of incorporation of CAM into the medical curriculum. CONCLUSION: Despite being aware of the usefulness of CAM only a few medical students had pursued further knowledge. In order to prepare the medical students of today to better fulfill their duties as tomorrow's physicians, consideration should be given to incorporating CAM in the medical curriculum.