Context The effects of COVID-19 on the thyroid axis remain uncertain. Recent evidence has been conflicting, with both thyrotoxicosis and suppression of thyroid function reported. Objective We aimed to detail the acute effects of COVID-19 on thyroid function and determine if these effects persisted on recovery from COVID-19. Design A cohort observational study was conducted. Participants and Setting Adult patients admitted to Imperial College Healthcare National Health Service Trust, London, UK, with suspected COVID-19 between March 9 to April 22, 2020, were included, excluding those with preexisting thyroid disease and those missing either free thyroxine (FT4) or thyrotropin (TSH) measurements. Of 456 patients, 334 had COVID-19 and 122 did not. Main Outcome Measures TSH and FT4 measurements were recorded at admission, and where available, in 2019 and at COVID-19 follow-up. Results Most patients (86.6%) presenting with COVID-19 were euthyroid, with none presenting with overt thyrotoxicosis. Patients with COVID-19 had a lower admission TSH and FT4 compared to those without COVID-19. In the COVID-19 patients with matching baseline thyroid function tests from 2019 (n = 185 for TSH and 104 for FT4), TSH and FT4 both were reduced at admission compared to baseline. In a complete case analysis of COVID-19 patients with TSH measurements at follow-up, admission, and baseline (n = 55), TSH was seen to recover to baseline at follow-up. Conclusions Most patients with COVID-19 present with euthyroidism. We observed mild reductions in TSH and FT4 in keeping with a nonthyroidal illness syndrome. Furthermore, in survivors of COVID-19, thyroid function tests at follow-up returned to baseline.
Introduction: Polycystic ovarian syndrome (PCOS) is a leading cause of female subfertility worldwide, however due to the heterogeneity of the disorder, the criteria for diagnosis remains subject to conjecture. In the present study, we evaluate the utility of serum Anti-Müllerian hormone (AMH) in the diagnosis of menstrual disturbance due to PCOS.Method: Menstrual cycle length, serum AMH, gonadotropin and sex-hormone levels, total antral follicle count (AFC), body mass index (BMI) and ovarian morphology on ultrasound were analyzed in a cohort of 187 non-obese women, aged 18–35 years, screened for participation in a clinical trial of fertility treatment between 2013 and 2016 at a tertiary reproductive endocrine center.Results: Serum AMH was higher in women with menstrual disturbance when compared to those with regular cycles (65.6 vs. 34.8 pmol/L; P < 0.0001). The odds of menstrual disturbance was increased 28.5-fold (95% CI 3.6–227.3) in women with serum AMH >60 pmol/L, in comparison to those with an AMH < 15 pmol/L. AMH better discriminated women with menstrual disturbance (area under ROC 0.77) from those with regular menstrual cycles than AFC (area under ROC 0.67), however the combination of the two markers increased discrimination than either measure alone (0.83; 95% CI 0.77–0.89). Serum AMH was higher in women with all three cardinal features of PCOS (menstrual disturbance, hyperandrogenism, polycystic ovarian morphology) when compared to women with none of these features (65.6 vs. 14.6 pmol/L; P < 0.0001). The odds of menstrual disturbance were increased by 10.7-fold (95% CI 2.4–47.1) in women with bilateral polycystic morphology ovaries than those with normal ovarian morphology. BMI was a stronger predictor of free androgen index (FAI) than either AMH or AFC.Conclusion: Serum AMH could serve as a useful biomarker to indicate the risk of menstrual disturbance due to PCOS. Women with higher AMH levels had increased rates of menstrual disturbance and an increased number of features of PCOS.
PurposeTo review the clinical and biochemical characteristics and clinical outcome of patients presenting with pituitary apoplexy to a tertiary centre.MethodsWe retrospectively reviewed the clinical features, predisposing factors, biochemistry and clinical outcome of patients presenting with pituitary apoplexy to Imperial College Healthcare NHS Trust between 1991 and 2015.ResultsWe identified 64 patients with pituitary apoplexy (more complete clinical records were available in 52 patients). The median age at presentation was 46.7 years (IQR 31.5–57.0 years). Pituitary apoplexy was the first presentation of pituitary disease in 38/52 of patients and predisposing factors were identified in 28/52. Pituitary apoplexy predominantly occurred in patients with non-functioning pituitary adenomas (47/52). Headache was most commonly described as sudden onset, severe, lateralising to the frontal or temporal regions. Symptoms of meningeal irritation were reported in 7/18 and visual abnormalities in 22/35. A pre-treatment serum cortisol <100 nmol/L was recorded in 12/31 of patients. All patients with visual disturbance had some resolution of their visual symptoms whether managed surgically (14/14) or conservatively (5/5), although pituitary endocrine function did not fully recover in any patient.ConclusionsIn conclusion, these data describe the clinical features of pituitary apoplexy to aid the clinician in diagnosing this rare emergency presentation of pituitary disease. Prospective multicentre studies of the presentation of pituitary apoplexy are required to further characterise presentation and outcomes.
Introduction: Ovarian follicle growth is a key step in the success of assisted reproductive treatment, but limited data exists to directly relate follicle growth to recombinant FSH (rFSH) dose. In this study, we aim to evaluate FSH requirements for follicular growth during controlled ovarian stimulation. Method: Single center retrospective cohort study of 1,034 IVF cycles conducted between January 2012–January 2016 at Hammersmith Hospital IVF unit, London, UK. Median follicle size after 5 days of stimulation with rFSH and the proportion of antral follicles recruited were analyzed in women treated with rFSH alone to induce follicular growth during IVF treatment. Results: Starting rFSH dose adjusted for body weight (iU/kg) predicted serum FSH level after 5 days of rFSH ( r 2 = 0.352, p < 0.0001), median follicle size after 5 days of rFSH, and the proportion of antral follicles recruited by the end of stimulation. Day 5 median follicle size predicted median follicle size on subsequent ultrasound scans ( r 2 = 0.58–0.62; p < 0.0001), and hence time to oocyte maturation trigger ( r 2 = 0.22, P < 0.0001). Insufficient rFSH starting dose that required >5% dose-increase was associated with increased variability in follicle size on the day of oocyte maturation trigger, and negatively impacted the number of mature oocytes retrieved. Conclusion: Weight-adjusted rFSH dose correlates with follicular growth during ovarian stimulation. Early recruitment of follicles using a sufficient dose of rFSH from the start of stimulation was associated with reduced variability in follicle size at time of oocyte maturation trigger and an increased number of mature oocytes retrieved.
Insulin-induced hypoglycemia is a major barrier to the treatment of type-1 diabetes (T1D). Accordingly, it is important that we understand the mechanisms regulating the circulating levels of glucagon - the body's principal blood glucose-elevating hormone which is secreted from alpha-cells of the pancreatic islets. Varying glucose over the range of concentrations that occur physiologically between the fed and fuel-deprived states (from 8 to 4 mM) has no significant effect on glucagon secretion in the perfused mouse pancreas or in isolated mouse islets (in vitro) and yet associates with dramatic changes in plasma glucagon in vivo. The identity of the systemic factor(s) that stimulates glucagon secretion remains unknown. Here, we show that arginine-vasopressin (AVP), secreted from the posterior pituitary, stimulates glucagon secretion. Glucagon-secreting alpha-cells express high levels of the vasopressin 1b receptor gene (Avpr1b). Activation of AVP neurons in vivo increased circulating copeptin (the C-terminal segment of the AVP precursor peptide, a stable surrogate marker of AVP) and increased blood glucose; effects blocked by pharmacological antagonism of either the glucagon receptor or vasopressin 1b receptor. AVP also mediates the stimulatory effects of hypoglycemia produced by exogenous insulin and 2-deoxy-D-glucose on glucagon secretion. We show that the A1/C1 neurons of the medulla oblongata drive AVP neuron activation in response to insulin-induced hypoglycemia. Exogenous injection of AVP in vivo increased cytoplasmic Ca2+ in alpha-cells (implanted into the anterior chamber of the eye) and glucagon release. Hypoglycemia also increases circulating levels of AVP in humans and this hormone stimulates glucagon secretion from isolated human islets. In patients with T1D, hypoglycemia failed to increase both plasma copeptin and glucagon levels. These findings suggest that AVP is a physiological systemic regulator of glucagon secretion and that this mechanism becomes impaired in T1D.
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