Census of heat tolerance among Florida's threatened staghorn corals finds resilient individuals throughout existing nursery populations

The rapid loss of reef-building corals owing to ocean warming is driving the development of interventions such as coral propagation and restoration, selective breeding and assisted gene flow. Many of these interventions target naturally heat-tolerant individuals to boost climate resilience, but the challenges of quickly and reliably quantifying heat tolerance and identifying thermotolerant individuals have hampered implementation. Here, we used coral bleaching automated stress systems to perform rapid, standardized heat tolerance assays on 229 colonies of Acropora cervicornis across six coral nurseries spanning Florida's Coral Reef, USA. Analysis of heat stress dose–response curves for each colony revealed a broad range in thermal tolerance among individuals (approx. 2.5°C range in F v /F m ED50), with highly reproducible rankings across independent tests ( r = 0.76). Most phenotypic variation occurred within nurseries rather than between them, pointing to a potentially dominant role of fixed genetic effects in setting thermal tolerance and widespread distribution of tolerant individuals throughout the population. The identification of tolerant individuals provides immediately actionable information to optimize nursery and restoration programmes for Florida's threatened staghorn corals. This work further provides a blueprint for future efforts to identify and source thermally tolerant corals for conservation interventions worldwide.

Adrenal Cushing’s in Pregnancy, Managed with Metyrapone to Optimize for Adrenalectomy at 27 Weeks Gestation

Background: Cushing’s syndrome in pregnancy is associated with increased fetal and maternal morbidity and mortality. Prompt diagnosis and management during pregnancy is critical to improving these outcomes. Clinical Case: Patient is a 28-year-old female who presented to our hospital at 25 weeks of pregnancy with severe striae, high blood pressure, mildly elevated blood sugars and hypokalemia. Striae began in the 6th week of her pregnancy but progressed in the 2nd trimester to encompass multiple sections of skin. Blood pressure on presentation was 146/100 mmHg (on labetalol) and fasting glucose 113 mg/dL (goal <95 mg/dL in pregnancy). Labs were consistent with ACTH-independent Cushing’s Syndrome: AM serum cortisol of 42.3 mcg/dL (n < 22.6 mcg/dL), PM serum cortisol of 46 mcg/dL (n < 11.9 mcg/dL), ACTH of <1 pg/mL (normal 7–63 pg/mL), 24-hour urinary free cortisol of 1388 mcg/day (n <45 mcg/day), and salivary midnight cortisol of 2.2 mcg/dL (n <0.3 mcg/dL). An abdominal MRI scan without contrast showed a 3.2 cm fat-containing right adrenal lesion consistent with an adenoma. The fetus was large for gestational age at 98th percentile. Patient was started on metyrapone 250 mg twice daily, which was titrated up to 250 mg three times daily. Her blood pressure and glucose levels, treated with labetalol and insulin respectively, improved on metyrapone. Surgery, Maternal Fetal Medicine, Endocrine, Anesthesia, and Neonatal physicians reviewed her case at an interdisciplinary meeting. She received metyrapone for 1 week pre-operatively. AM serum cortisol improved to 21.4 mcg/dL and 24-hour urinary free cortisol improved to 139 mcg/day. She underwent laparoscopic right adrenalectomy at 27 weeks of pregnancy. Betamethasone was given 2 days prior to ensure fetal lung maturity in case of preterm labor. Stress dose hydrocortisone 100 mg was given intra-operatively. Fetal heart monitoring was normal throughout the surgery and post-operatively. After surgery, metyrapone was stopped and hydrocortisone was tapered to 20 mg and 10 mg. Five weeks after her adrenalectomy, striae decreased in size and glucoses normalized. Remarkably, fetal size is now appropriate for gestational age in the 62th percentile at 34 weeks. However, blood pressure remains elevated and is being treated with labetalol. She is planned for induction of labor at 37 weeks due to her elevated blood pressures and will be given stress dose steroids intraoperatively. Conclusion: Medical management of adrenal Cushing’s in pregnancy with metyrapone followed by adrenalectomy required a multidisciplinary team approach. Patient underwent successful adrenalectomy without complications of severe hypercortisolism, including infection, thromboembolism, pre-eclampsia, preterm labor and pregnancy loss. After surgery, there was normalization of maternal blood sugars as well as fetal size, and persistent, but improved, elevated blood pressure.

Corticosteroids Replacement in a Patient With Panhypopituitarism and COVID-19 Infection

Background: Hypopituitarism refers to complete or partial insufficiency of pituitary hormone secretion and patients require lifelong hormone replacement. Those with ACTH deficiency rely on exogenous glucocorticoids and at times of intercurrent illness require stress doses to prevent an adrenal crisis. The benefits and adverse effects of corticosteroids for treatment of COVID-19 pneumonia are currently under investigation. We report our experience in a patient with COVID-19 pneumonia who received high dose corticosteroids for panhypopituitarism. Clinical Case: A 51-year-old man presented with one-week history of fever and generalized weakness. He had been diagnosed with a non-functional pituitary macro-adenoma causing panhypopituitarism 1 year ago when he developed generalized tonic-clonic seizures. He underwent trans-sphenoidal resection of the pituitary adenoma. However, he then discontinued his hormonal therapy and was lost to follow up. He had postural hypotension but was not tachypneic or hypoxemic. He tested positive for COVID-19 and chest x-ray showed prominent bilateral broncho-vascular markings; he was hospitalized as mild COVID-19 pneumonia. Laboratory investigations revealed secondary adrenal insufficiency, secondary hypothyroidism and hypogonadotropic hypogonadism. MRI of the pituitary now showed persistence of the pituitary macroadenoma, measuring 3.5 x 3.7 x 2.4 cm in dimensions, causing sellar obliteration and left cavernous sinus invasion. Treatment with stress dose steroids, Hydrocortisone 50 mg 4 times daily was initiated, followed by thyroid hormone replacement with Levothyroxine 125 mcg daily. He also received antivirals and supportive care for COVID-19, guided by local hospital protocol. After significant clinical improvement, steroids were tapered down and he was discharged on a maintenance dose of 20 mg hydrocortisone per day in divided doses. The patient was stable at outpatient follow up after one month. He was started on testosterone replacement for erectile dysfunction due to hypogonadotropic hypogonadism. He was offered surgery for complete resection of the residual pituitary adenoma, but he declined and preferred to continue medical therapy. Conclusion: Hypopituitarism is associated with significant morbidity and premature mortality, a key risk factor being cortisol deficiency. Adrenal crisis is a life-threatening medical emergency and remains an important cause of death in patients with adrenal insufficiency. These patients are also vulnerable to develop severe complications from COVID-19 infection due to the absence of normal cortisol responses to stress. Despite receiving stress dose corticosteroids, this high-risk patient recovered from COVID-19 pneumonia without complications. These findings support the use of corticosteroids when necessary for treatment of coexisting conditions in patients with COVID-19.

Perioperative glucocorticoid management based on current evidence

Glucocorticoid preparations, adreno-cortical steroids, with strong anti-inflammatory and immunosuppressive effects, are widely used for treating various diseases. The number of patients exposed to steroid therapy prior to surgery is increasing. When these patients present for surgery, the anesthesiologist must decide whether to administer perioperative steroid supplementation. Stress-dose glucocorticoid administration is required during the perioperative period because of the possibility of failure of cortisol secretion to cope with the increased cortisol requirement due to surgical stress, adrenal insufficiency, hemodynamic instability, and the possibility of adrenal crisis. Therefore, glucocorticoids should be supplemented at the same level as that of normal physiological response to surgical stress by evaluating the invasiveness of surgery and inhibition of the hypothalamus-pituitary-adrenal axis. Various textbooks and research articles recommend the stress-dose of glucocorticoids during perioperative periods. It has been commonly suggested that glucocorticoids should be administered in an amount equivalent to about 100 mg of cortisol for major surgery because it induces approximately 5 times the normal secretion. However, more studies, with appropriate power, regarding the administration of stress-dose glucocorticoids are still required, and evaluation of patients with possible adrenal insufficiency and appropriate glucocorticoid administration based on surgical stress will help improve the prognosis.

Critical Low Catastrophe: A Case Report of Treatment-Refractory Hypoglycemia following Overdose of Long-Acting Insulin

Overdose of long-acting insulin can cause unpredictable hypoglycemia for prolonged periods of time. The initial treatment of hypoglycemia includes oral carbohydrate intake as able and/or parenteral dextrose infusion. Refractory hypoglycemia following these interventions presents a clinical challenge in the absence of clear guidelines for management. Octreotide has sometimes been used, but its use is generally limited to sulfonylurea overdose. In this case report, we present a case of refractory hypoglycemia following an overdose of 900 units of long-acting insulin glargine that failed to respond to usual modes of therapy mentioned above. Stress-dose corticosteroids were then initiated, followed by subsequent improvement in IV dextrose and glucagon requirements and blood glucose levels. Hence, corticosteroids may serve as an adjunctive therapy in managing hypoglycemia and can be considered earlier in the course of treatment in patients with refractory hypoglycemia to prevent volume overload, especially when large volumes of dextrose infusions are required.