Optimising prednisolone or prednisone replacement in adrenal insufficiency.

Context: Patients with adrenal insufficiency (AI) have a higher mortality than the general population, possibly because of excess glucocorticoid exposure at inappropriate times. The cortisol circadian rhythm is difficult to mimic with twice- or thrice-daily hydrocortisone. Prednisolone is a once-daily alternative which may improve patient compliance through its convenience. Objectives: Prednisolone day curves can be used to accurately downtitrate patients to the minimum effective dose. This study aimed to review prednisolone day curves and determine therapeutic ranges at different time points after administration. Methods: Between August 2013 and May 2021, 108 prednisolone day curves from 76 individuals receiving prednisolone replacement were analysed. Prednisolone concentrations were determined by ultra-high-performance liquid chromatography-tandem mass spectrometry. Spearman's correlation coefficient was used to determine the relationship between 2-, 4-, and 6-h prednisolone levels compared to the previously validated standard 8-h prednisolone level (15-25 µg/L). Results: The median dose was 4 mg of prednisolone once daily. There was a strong correlation between the 4- and 8-h (R = 0.8829, P ≤ 0.0001) and 6- and 8-h prednisolone levels (R = 0.9530, P ≤ 0.0001). Target ranges for prednisolone were 37-62 µg/L at 4 h, 24-39 µg/L at 6 h, and 15-25 µg/L at 8 h. Prednisolone doses were successfully reduced in 21 individuals, and of these, 3 were reduced to 2 mg once daily. All patients were well upon follow-up. Conclusion: This is the largest evaluation of oral prednisolone pharmacokinetics in humans. Low-dose prednisolone of 2-4 mg is safe and effective in most patients with AI. Doses can be titrated with either 4-, 6-, or 8-h single time point drug levels.

The gut microbiota and metabolome are associated with diminished COVID-19 vaccine-induced antibody responses in immunosuppressed inflammatory bowel disease patients.

BACKGROUND: Patients with inflammatory bowel disease (IBD) treated with anti-TNF therapy exhibit attenuated humoral immune responses to vaccination against SARS-CoV-2. The gut microbiota and its functional metabolic output, which are perturbed in IBD, play an important role in shaping host immune responses. We explored whether the gut microbiota and metabolome could explain variation in anti-SARS-CoV-2 vaccination responses in immunosuppressed IBD patients. METHODS: Faecal and serum samples were prospectively collected from infliximab-treated patients with IBD in the CLARITY-IBD study undergoing vaccination against SARS-CoV-2. Antibody responses were measured following two doses of either ChAdOx1 nCoV-19 or BNT162b2 vaccine. Patients were classified as having responses above or below the geometric mean of the wider CLARITY-IBD cohort. 16S rRNA gene amplicon sequencing, nuclear magnetic resonance (NMR) spectroscopy and bile acid profiling with ultra-high-performance liquid chromatography mass spectrometry (UHPLC-MS) were performed on faecal samples. Univariate, multivariable and correlation analyses were performed to determine gut microbial and metabolomic predictors of response to vaccination. FINDINGS: Forty-three infliximab-treated patients with IBD were recruited (30 Crohn's disease, 12 ulcerative colitis, 1 IBD-unclassified; 26 with concomitant thiopurine therapy). Eight patients had evidence of prior SARS-CoV-2 infection. Seventeen patients (39.5%) had a serological response below the geometric mean. Gut microbiota diversity was lower in below average responders (p = 0.037). Bilophila abundance was associated with better serological response, while Streptococcus was associated with poorer response. The faecal metabolome was distinct between above and below average responders (OPLS-DA R2X 0.25, R2Y 0.26, Q2 0.15; CV-ANOVA p = 0.038). Trimethylamine, isobutyrate and omega-muricholic acid were associated with better response, while succinate, phenylalanine, taurolithocholate and taurodeoxycholate were associated with poorer response. INTERPRETATION: Our data suggest that there is an association between the gut microbiota and variable serological response to vaccination against SARS-CoV-2 in immunocompromised patients. Microbial metabolites including trimethylamine may be important in mitigating anti-TNF-induced attenuation of the immune response. FUNDING: JLA is the recipient of an NIHR Academic Clinical Lectureship (CL-2019-21-502), funded by Imperial College London and The Joyce and Norman Freed Charitable Trust. BHM is the recipient of an NIHR Academic Clinical Lectureship (CL-2019-21-002). The Division of Digestive Diseases at Imperial College London receives financial and infrastructure support from the NIHR Imperial Biomedical Research Centre (BRC) based at Imperial College Healthcare NHS Trust and Imperial College London. Metabolomics studies were performed at the MRC-NIHR National Phenome Centre at Imperial College London; this work was supported by the Medical Research Council (MRC), the National Institute of Health Research (NIHR) (grant number MC_PC_12025) and infrastructure support was provided by the NIHR Imperial Biomedical Research Centre (BRC). The NIHR Exeter Clinical Research Facility is a partnership between the University of Exeter Medical School College of Medicine and Health, and Royal Devon and Exeter NHS Foundation Trust. This project is supported by the National Institute for Health Research (NIHR) Exeter Clinical Research Facility. The views expressed are those of the authors and not necessarily those of the NIHR or the UK Department of Health and Social Care.

Late-night salivary cortisol and cortisone should be the initial screening test for Cushing's syndrome.

Endogenous Cushing's syndrome (CS) poses considerable diagnostic challenges. Although late-night salivary cortisol (LNSC) is recommended as a first-line screening investigation, it remains the least widely used test in many countries. The combined measurement of LNSC and late-night salivary cortisone (LNS cortisone) has shown to further improve diagnostic accuracy. We present a retrospective study in a tertiary referral centre comparing LNSC, LNS cortisone, overnight dexamethasone suppression test, low-dose dexamethasone suppression test and 24-h urinary free cortisol results of patients investigated for CS. Patients were categorised into those who had CS (21 patients) and those who did not (33 patients). LNSC had a sensitivity of 95% and a specificity of 91%. LNS cortisone had a specificity of 100% and a sensitivity of 86%. With an optimal cut-off for LNS cortisone of >14.5 nmol/L the sensitivity was 95.2%, and the specificity was 100% with an area under the curve of 0.997, for diagnosing CS. Saliva collection is non-invasive and can be carried out at home. We therefore advocate simultaneous measurement of LNSC and LNS cortisone as the first-line screening test to evaluate patients with suspected CS.

Prednisolone has the same cardiovascular risk profile as hydrocortisone in glucocorticoid replacement.

INTRODUCTION: Patients who need glucocorticoid replacement in both primary and secondary adrenal insufficiency (AI) have the choice of either once-daily prednisolone or thrice-daily hydrocortisone. A recent European study found no difference between prednisolone and hydrocortisone users in several markers including glucose, weight, body mass index, systolic and diastolic blood pressure and waist circumference, although an increase in cholesterol and low-density lipoprotein (LDL) was suggested in a subgroup of these patients. The aim of this study was to expand the evidence base for the use of these agents as replacement therapy. METHODS: Data from 82 patients on hydrocortisone and 64 patients on prednisolone for AI at Imperial College Healthcare NHS Trust were analysed. RESULTS: There was no significant difference in total cholesterol, LDL levels or any other risk factors between hydrocortisone and prednisolone patients. Prednisolone was subjectively significantly more convenient than hydrocortisone (P = 0.048). CONCLUSIONS: Prednisolone once daily is more convenient than hydrocortisone thrice daily, and there is no difference in the markers of cardiovascular risk measured. Because prednisolone mimics the circadian rhythm better than other glucocorticoids, it should be considered as an alternative to hydrocortisone for AI.

Diagnostic confusion resolved by being upbeat.

The classical stroke presentation - captured by the public health campaign mnemonic FAST (face, arm, speech, time) - does not apply in a large number of stroke cases; yet establishing a prompt diagnosis is imperative for optimal management. Here, we describe a patient with acute bulbar weakness, numbness in all extremities and an apparently normal magnetic resonance imaging (MRI) of the brain upon admission for whom even the fundamental question of whether this reflected a central or peripheral nervous system process was unclear. The critical localizing sign was upbeat nystagmus that denotes a brainstem cause. MRI of the brain in the second week confirmed a diagnosis of medial medullary infarction.