Development of diagnostic algorithm for Cushing's syndrome: a tertiary centre experience.

PURPOSE: No consensus exists as the gold standard for Cushing's Syndrome (CS) screening. This study aimed to evaluate the diagnostic accuracy and utility of late-night salivary cortisol (LNSC) and cortisone (LNSE), overnight dexamethasone suppression test (ODST), and urinary free cortisol (UFC) in developing a screening algorithm for CS. METHODS: A retrospective, single-centre analysis on 93 adult patients referred to the Oxford Centre for Diabetes, Endocrinology, and Metabolism for CS evaluation (2017-2022). Data were analysed using binomial logistic regression and area under the receiver-operating curve (AUROC). RESULTS: Fifty-three patients were diagnosed with CS. LNSC (sensitivity 87.5%, specificity 64.9%, AUC 0.76), LNSE (sensitivity 72.4%, specificity 85.7%, AUC 0.79), and ODST (sensitivity 94.7%, specificity 52.1%; AUC 0.74) demonstrated comparable effectiveness for CS diagnosis. Their combined application increased diagnostic accuracy (AUC 0.91). UFC was not statistically significant. Pre-test clinical symptom inclusion improved screening test performance (AUC LNSC: 0.83; LNSE: 0.84; ODST: 0.82). For CD diagnosis, LNSE + LNSC (AUC 0.95) outperformed ODST. Combining these with ACTH levels < 12.6 pmol/L perfectly distinguished MACS (AUC 1.00). ODST (AUC 0.76) exhibited superior performance (sensitivity 100.0%, specificity 52.2%) in MACS detection. CONCLUSIONS: LNSC, LNSE, and ODST are robust tools for CS screening, with their combined use offering the highest diagnostic precision. LNSE, especially when used with LNSC, is highly effective for CD diagnosis, exceeding ODST accuracy. ODST is preferable for MACS identification. Integrating ACTH levels markedly improves differentiation between CD and MACS. Conversely, UFC shows limited diagnostic utility.

Parenchymal involvement on CT pulmonary angiography in SARS-CoV-2 Alpha variant infection and correlation of COVID-19 CT severity score with clinical disease severity and short-term prognosis in a UK cohort.

AIM: To determine if there is a difference in radiological, biochemical, or clinical severity between patients infected with Alpha-variant SARS-CoV-2 compared with those infected with pre-existing strains, and to determine if the computed tomography (CT) severity score (CTSS) for COVID-19 pneumonitis correlates with clinical severity and can prognosticate outcomes. MATERIALS AND METHODS: Blinded CTSS scoring was applied to 137 hospital patients who had undergone both CT pulmonary angiography (CTPA) and whole-genome sequencing of SARS-CoV-2 within 14 days of CTPA between 1/12/20-5/1/21. RESULTS: There was no evidence of a difference in imaging severity on CTPA, viral load, clinical parameters of severity, or outcomes between Alpha and preceding variants. CTSS on CTPA strongly correlates with clinical and biochemical severity at the time of CTPA, and with patient outcomes. Classifying CTSS into a binary value of "high" and "low", with a cut-off score of 14, patients with a high score have a significantly increased risk of deterioration, as defined by subsequent admission to critical care or death (multivariate hazard ratio [HR] 2.76, p<0.001), and hospital length of stay (17.4 versus 7.9 days, p<0.0001). CONCLUSION: There was no evidence of a difference in radiological severity of Alpha variant infection compared with pre-existing strains. High CTSS applied to CTPA is associated with increased risk of COVID-19 severity and poorer clinical outcomes and may be of use particularly in settings where CT is not performed for diagnosis of COVID-19 but rather is used following clinical deterioration.

Clinical Reliability of point-of-care tests to support community based acute ambulatory care.

OBJECTIVE: To ensure clinicians can rely on point-of-care testing results, we assessed agreement between point-of-care tests for creatinine, urea, sodium, potassium, calcium, Hb, INR, CRP and subsequent corresponding laboratory tests. PARTICIPANTS: Community-dwelling adults referred to a community-based acute ambulatory care unit. INTERVENTIONS: The Abbott i-STATTM (Hb, clinical chemistry, INR) and the AfinionTM Analyser (CRP) and corresponding laboratory analyses. OUTCOMES: Agreement (Bland-Altman) and bias (Passing-Bablok regression). RESULTS: Among 462 adults we found an absolute mean difference between point-of-care and central laboratory analyses of 6.4g/L (95%LOA -7.9 to +20.6) for haemoglobin, -0.5mmol/L (95%LOA -4.5 to +3.5) for sodium, 0.2mmol/L (95%LOA -0.6 to +0.9) for potassium, 0.0mmol/L (95%LOA -0.3 to +0.3) for calcium, 9.0 µmol/L (95%LOA -18.5 to +36.4) for creatinine, 0.0mmol/L (95%LOA -2.7 to +2.6) for urea, -0.2 (95%LOA -2.4 to +2.0) for INR, -5.0 mg/L (95%LOA -24.4 to +14.4) for CRP. CONCLUSIONS: There was acceptable agreement and bias for these analytes, except for haemoglobin and creatinine.

Reduced kidney function at presentation in unselected acute emergency medical admissions: incidence, outcome and associated factors.

We sought to assess the impact of renal impairment on acute medical admissions and to identify potential contributory factors to admissions involving renal impairment at presentation. In a prospective cohort study, 29.5% of all acute medical emergency admissions had an eGFR <60ml/min/1.73m2 at presentation. Of these, 19.9% had definite chronic kidney disease and 8.4% had definite acute kidney injury. Detailed analysis of a random subset of patients with an eGFR <60ml/min/1.73m2 at presentation demonstrated that the major reasons for admission included falls, dehydration and fluid overload. 46% were on diuretics and 53% were on an ACEI or ARB or both. Gastrointestinal disturbance and recent medication changes were common and diuretic use persisted even with diarrhoea or vomiting.

Faecal immunochemical testing (FIT): sources of result variation based on three years of routine testing of symptomatic patients in English primary care.

Introduction: We aimed to determine the analytical capabilities of a commonly used faecal immunochemical test (FIT) to detect faecal haemoglobin (Hb) in symptomatic people attending primary care in the context of the English NICE DG30 guidance.Materials and Methods: Data obtained from independent verification studies and clinical testing of the HM-JACKarc FIT method in routine primary care practice were analysed to derive performance characteristics.Results: Detection capabilities for the FIT method were 0.5 µg/g (limit of blank), 1.3 µg/g (limit of detection) and 3.0 µg/g (limit of quantitation). Of 33 non-homogenized specimens, 31 (93.9%) analysed in triplicate were consistently categorized relative to 10 µg/g, compared to all 33 (100%) homogenized specimens. Imprecision was higher (median 27.8%, (range 20.5% to 48.6%)) in non-homogenized specimens than in homogenized specimens (10.2%, (7.0 to 13.5%)). Considerable variation was observed in sequential clinical specimens from individual patients but no positive or negative trend in specimen degradation was observed over time (p = 0.26).Discussion: The FIT immunoassay evaluated is capable of detecting faecal Hb at concentrations well below the DG30 threshold of 10 µg/g and is suitable for application in this context. The greatest practical challenge to FIT performance is reproducible sampling, the pre-analytical step associated with most variability. Further research should focus on reducing sampling variability, particularly as post-COVID-19 guidance recommends greater FIT utilization.

Persistent individual tracking within overall improvement in HbA1c in a UK paediatric diabetes clinic over 15 years.

INTRODUCTION: There is some evidence of long-term tracking of HbA(1c) levels within diabetes centres, but little evidence of individual tracking. METHODS: HbA(1c) levels of children in the clinic over a period of 15 years were retrieved from the clinical chemistry laboratory information system. We measured the correlation of HbA(1c) between years (Spearman and Pearson rank correlation), as well as the relationship of HbA(1c) with age and the change over time in the clinic. RESULTS: Data were collected from 362 children and young people [158 female (44%)], aged 0-18 years (median 10.4 years), with 0-13.6 years of follow-up (median 4.7 years). Mean HbA(1c) levels fell from 9.3 ± 1.5% (78 ± 16 mmol/mol) in 2001 to 8.1 ± 1.3% (65 ± 14 mmol/mol) in 2009 in those at least 6 months after diagnosis (P<0.0001). HbA(1c) levels gradually rise with increasing age. HbA(1c) levels from year to year are significantly correlated. This is better for adjacent than subsequent years, but there is a significant correlation up to 9 years from diagnosis. Only 4 of 49 children with a 6-month HbA(1c) level of 9% (75 mmol/mol) or more had a long-term (2-5 years) median HbA(1c) <8% (64 mmol/mol). CONCLUSIONS: HbA(1c) levels track in individuals within an improvement in overall clinic levels, suggesting that, if optimal control can be achieved in the first 6 months, it can persist for up to 9 years.

An 'n-of-1' placebo-controlled crossover trial of intravenous immunoglobulin as adjuvant therapy in refractory pemphigus vulgaris.

BACKGROUND: Pemphigus vulgaris (PV) is an organ-specific autoimmune blistering mucocutaneous disorder that is potentially fatal. High-dose intravenous immunoglobulin (IVIg) is increasingly used in the treatment of autoimmune diseases and it has been reported that it may also be effective in PV. OBJECTIVES: To evaluate prospectively the efficacy of IVIg for PV using an 'n-of-1' placebo-controlled trial. METHODS: A randomized, placebo-controlled, crossover trial of IVIg was conducted in a single patient with severe PV, comprising two phases of six consecutive months of either IVIg or placebo infusion. Before the commencement of the trial, the patient had received 18 months of IVIg but concerns about the continuing therapeutic efficacy of IVIg led to the double-blind placebo-controlled 'n-of-1' trial of IVIg. RESULTS: Pemphigus autoantibody titres were significantly higher when on placebo compared with IVIg treatment (median 1 : 80 vs. 1 : 20, P = 0.007), desmoglein 3 (126 vs. 79, P = 0.004) and desmoglein 1 antibody levels (126 vs. 94, P = 0.004). There was a significant improvement in subjective disease activity scores while on IVIg compared with placebo (mean overall score 11.6 vs. 20.6, P < 0.0001). CONCLUSIONS: The results of this study confirm a beneficial effect of IVIg in the management of refractory PV.

Longitudinal screening of serum lipids in children and adolescents with Type 1 diabetes in a UK clinic population.

AIMS: To determine the prevalence of abnormal lipid levels in a large group of children and adolescents with Type 1 diabetes and to examine the changes longitudinally. In addition, to study the relationships of any lipid abnormalities to glycaemic control, age and duration of diabetes. METHODS: Non-fasting blood samples were taken annually from all the patients in the Oxford Children's diabetes clinic and total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, triglycerides (TG) and glycated haemoglobin (HbA(1c)) measured over a period of 8 years. Low-density lipoprotein (LDL) cholesterol and non-HDL were calculated from these values and compared. Tests performed less than 4 months after diagnosis were excluded. RESULTS: A total of 229 children had complete data from more than 1 year and 798 sets of data were examined. TC was lower in males and increased with duration of diabetes and with increasing HbA(1c). HDL cholesterol fell with increasing age, but independently increased with duration, and was not related to HbA(1c). LDL cholesterol and non-HDL cholesterol were highly correlated (r = 0.9). Both were lower in males and increased with duration of diabetes. Non-HDL cholesterol increased with HbA(1c). A total of 23.7% had HDL cholesterol < 1.1 mmol/l and 22.5% had TC > 5.2 mmol/l. Thirty-eight per cent had LDL cholesterol > 2.6 mmol/l and 10.8% > 3.4 mmol/l, the thresholds for lifestyle and drug intervention respectively. CONCLUSIONS: Abnormalities in plasma lipid levels are common in this age group and the prevalence increases with poor glycaemic control and with duration of diabetes. Around 10% of adolescents would fit criteria for lipid-lowering medication in adults, but further study is needed to examine the risks and benefits in this age group.

Kappa/lambda immunoglobulin distribution in Graves' thyroid-stimulating antibodies. Simultaneous analysis of C lambda gene polymorphisms.

From patients with untreated Graves' disease 11 sera showing high cAMP release in the FRTL-5 cell assay were studied for relative proportions of kappa or lambda Ig molecules showing cAMP releasing activity. Immunoabsorption of gamma-globulins was performed using monoclonal murine anti-kappa or anti-lambda antibodies linked to cyanogen bromide-activated sepharose. Specific kappa- or lambda-adsorbed fractions were also eluted from immunoabsorbents using chaotrophic thiocyanate buffers and equilibrated with pH 7.4 low salt buffer by dialysis. Immunoabsorption and elution experiments showed that five Graves' sera contained predominant cAMP-releasing activity within lambda Ig fractions, whereas two Graves' sera showed predominant cAMP-releasing activity in kappa Ig fractions. Four sera showed cAMP release approximately equally divided between kappa and lambda Ig both after immunoabsorption and specific anti-kappa or anti-lambda eluates were studied. C lambda genotypes were examined by Southern blotting and restriction fragment length polymorphism analysis of Eco RI-digested genomic DNA from 158 patients with Graves' disease in parallel with 112 normal controls and 29 patients with autoimmune hypothyroidism. Notable shifts in proportions of 8/8 and 18/18 genotypes were present when Graves' patients were compared with normal controls. Allelic frequencies and ratios of genotype 8 to 18 were significantly different (P less than 0.05) when Graves' patients were compared either to normal controls or to patients with autoimmune hypothyroidism.

Thyroid-stimulating antibody activity between different immunoglobulin G subclasses.

To investigate the distribution of thyroid-stimulating antibody (TSAb) activity between IgG subclasses, sera from 11 patients with Graves disease (including the National Institute of Biological Standards and Control (NIBSC) Research Standard, long acting thyroid stimulator-B) were fractionated by chromatography on affinity columns of monoclonal IgG subclass antibodies or protein A to deplete all but a single subclass. The resulting fractions were 98% or more pure for a single subclass. In all 11 patients, TSAb activity appeared to be confined to the IgG1 fraction as determined by cAMP production on addition of the fractions to the FRTL-5 rat thyroid cell line. In all of eight specimens from seven patients so tested, the whole serum activity was recovered in the IgG1 fraction, after adjusting for the recovery of the isotype from the column. TSAb activity in one serum comprised both lambda and kappa light chains but was IgG1 restricted. This IgG subclass restriction was not found when the same fractions were tested for thyroglobulin, microsomal/thyroid peroxidase, or tetanus toxoid antibody activity. Together with previous results showing marked restriction of both light chain usage and isoelectric point of TSAb, these results support the idea that Graves' disease may be the result of an oligo- or possibly monoclonal response at the B cell level.

Linear growth characteristics of congenitally GH-deficient infants from birth to one year of age.

Birth length has been reported to be either normal or reduced in infants with congenital GH deficiency (CGHD). We evaluated 46 infants with CGHD followed in a single regional medical center. All were born full term and had peak GH of less than 10 microg/liter after provocative stimulation. Length SD score at birth was normal but subsequently showed deceleration, at 6 months and 12 months of age, before GH treatment. The majority were delivered vaginally (83%), and delivery was uncomplicated in 61%. Four patients (9%) had breech vaginal delivery. Perinatal morbidities were found in 72% of infants and included jaundice (n = 17), hypoglycemia with or without seizure (n = 14), and hypoxemia (n = 5). Multiple pituitary hormone deficiencies were found in 85% of the subjects. Organic lesions were documented in all 22 subjects who had magnetic resonance imaging and in 4 of 11 subjects who had computed tomography scan. Only the hypoglycemic infants received early GH treatment. Growth data in hypoglycemic and normoglycemic CGHD infants were not significantly different. In our population, CGHD did not adversely affect fetal growth but is essential for normal linear growth during early infancy. Congenital developmental abnormalities in the hypothalamic-pituitary region are the most common cause of CGHD and are best diagnosed by an magnetic resonance imaging study.

Comparison of final heights of growth hormone-treated vs. untreated children with idiopathic growth failure.

We measured adult heights (Ht) of 94 healthy GH-sufficient children (peak GH > 10 ng/mL, polyclonal RIA) whose Ht at presentation were more than 2 SD below the mean for chronological age, with normal weight-to-Ht ratios, normal body proportions, and pathologic growth velocity for chronological age. Group 1 (n 36, 6 females) received standardized doses (0.3 mg/kg x week) of GH (mean duration = 41 months), while group 2 (n = 58, 17 females) received no treatment. Our conclusion was that the mean final Ht SD score in the GH-treated group (-1.5) was significantly greater than in the untreated group (-2.1); P < .001. Genetic predisposition to short stature was evident in both groups: the midparental Ht SD score was -1.1 in the treated and -1.0 in the untreated group. Midparental Ht was met or exceeded by 42% of the GH-treated group but only 15% of the untreated group. Final Ht was not significantly different from predicted Ht, except from GH-treated girls, who exceeded their predicted Ht. Although the mean Ht gains (6.8 cm in girls and 3 cm in boys) were modest and variable, GH treatment provided significantly better Ht outcomes for the majority of children with idiopathic growth failure.

Immunoassays for serum C-reactive protein employing fluorophore-labelled reactants.

Two simple rapid and precise fluorescence assays for determining serum levels of C-reactive protein (CRP) are described which employ sheep antibodies to CRP covalently linked to magnetisable cellulose/iron oxide particles. The first (a fluoroimmunoassay) is based on competitive binding of CRP in the sample or standard with fluorescein-labelled CRP, a 30 min incubation time, simple separation with a magnet followed by elution of the bound fraction into alkaline methanol and fluorescence quantitation. In the second (a 'sandwich' immunofluorometric assay) an excess of solid-phase linked antiserum is incubated with sample and fluorescein-labelled purified sheep anti-CRP immunoglobulin followed by separation, elution and quantitation of the bound fraction. The assays cover the ranges 3-400 mg/l and 3-70 mg/l respectively and the results correlate well with those obtained by radial immunodiffusion and radioimmunoassay.

Coronary artery disease and dyslipidemia within Europe: genetic variants in lipid transport gene loci in German subjects with premature coronary artery disease.

Fifteen polymorphisms in six lipid transport genes were studied in a German population for relationships with dyslipidemia and coronary artery disease (CAD), to investigate a possible genetic basis for the marked differences in mortality rates from coronary heart disease within Europe. In other populations these polymorphisms have all been associated with CAD or with phenotypes known to predispose to CAD. The apoAI PstI polymorphism (P<0.005) and the lipoprotein lipase Ser(447)-Ter mutation (P<0.005) were associated with plasma triglyceride concentrations. Additionally, the apoAI PstI polymorphism (P<0.05), the apoB XbaI polymorphism (P<0.05) and apoE phenotypes (P<0.05) were associated with plasma cholesterol concentrations. However, none of the allele frequencies of the polymorphisms studied were related to the presence, or absence, of coronary artery disease. Associations between five polymorphisms representing four lipid transport gene loci and dyslipidemia were demonstrated in this German population. It is possible that predisposition to dyslipidemia in Germany involves a particular selection of polymorphic loci, which are different from those identified in other European countries.

The use of fluorescein conjugated antisera to identify proteins on stained and dried electrophoresis strips.

Paraprotein bands discovered on routine electrophoresis may be identified immunologically without repeating the electrophoretic separation. It is only necessary to heat the stained and dried strip in a hot air oven to reactivate the antigenic sites and insolubilise the protein. The strip may then be stained using specific antisera conjugated with fluorescein. The absence of prozone phenomena greatly helps in typing of free light chains.

Solid phase radioimmunoassays for human C-reactive protein.

Two new, rapid and sensitive radioimmunoassays for human C-reactive protein (CRP) have been established using antiserum coupled to magnetizable cellulose particles, which facilitate phase separation. A single antibody method, using solid phase anti-CRP, provides a sensitivity of 50 microgram/l with a 1-h incubation time and intra- and inter-assay coefficients of variation of 10%. A double antibody method, using fluid phase rabbit anti-CRP serum and solid phase sheep anti-rabbit IgG serum, provides a sensitivity of 3 microgram/l with an overnight incubation and intra- and inter-assay coefficients of variation of 10%. Among 468 sera from normal adult volunteer blood donors the median CRP concentration was 800 microgram/l, interquartile range 340-1700 microgram/l and range 70-29,000 microgram/l. Ninety percent of samples contained less than 3 mg/l and 99% less than 10 mg/l. Low levels (14-650 microgram/l) of CRP were detected both in amniotic fluids and in cerebrospinal fluids.

C-reactive protein as an aid in the differentiation of functional and inflammatory bowel disorders.

Eighty-two patients were investigated on their first visit to the outpatient department of St. Mark's Hospital, London, for the assessment of abdominal symptoms. In addition to the clinical examination, a rectal biopsy, routine tests and appropriate special investigations, blood was taken from each patient for the determination of erythrocyte sedimentation rate, C-reactive protein and alpha-1-acid glycoprotein. Nineteen patients were finally diagnosed as having Crohn's disease, twenty-two ulcerative colitis, and forty-one functional bowel disorders. All the patients with Crohn's disease had an elevated erythrocyte sedimentation rate and C-reactive protein level as had 11 (50%) of the patients with ulcerative colitis, but none with functional disorders. All cases of ulcerative colitis could be diagnosed by rectal biopsy. Measurement of alpha-1-acid glycoprotein provided no additional diagnostic information. A combination of rectal biopsy, and measurement of the erythrocyte sedimentation rate and C-reactive protein successfully distinguishes between inflammatory disease of the large and small bowel and functional bowel syndrome.

Serum C-reactive protein in normal and infected neonates.

Serum C-reactive protein determinations were performed on well and sick neonates, in order to gain information about normal values and its value in the diagnosis of neonatal septicaemia. The median value in 48 cord sera was 200 micrograms/l (range 15 to greater than 6,000 micrograms/L); there was no correlation between paired maternal and cord serum CRP levels (12 pairs). Thirty-six children were followed from birth for a mean of 20 days. There were 21 episodes of confirmed infection in 16 children, each associated with a sustained rise in C-reactive protein, often commencing before there was clinical evidence of infection. In four patients with raised levels, infection was suspected, but no firm evidence was obtained. In the remaining 16 children there were no values above 10 mg/l, and the 95th centile was about 6 mg/l, with no difference between values obtained in the first three days of life and those found subsequently. Hyaline membrane disease and jaundice were not associated with a rise. Raised serum C-reactive proteins is a good indicator of the presence of infection in the neonatal period.

T and B cell reactivity to extraocular and skeletal muscle in Graves' ophthalmopathy.

We have sought human eye muscle membrane binding antibodies in patients with Graves' ophthalmopathy using an enzyme-linked immunoassay. Antibodies were found in patients with thyroid autoimmunity irrespective of eye signs, and binding correlated closely (r = 0.94) with binding to skeletal muscle, showing that these antibodies are not site-specific. T cells from patients with thyroid autoimmunity proliferated in response to eye muscle, but again this was not specific for eye muscle or the presence of ophthalmopathy. No single antigen was responsible for inducing proliferation. These results fail to confirm a recent report of eye muscle membrane binding antibodies in a high proportion of patients with ophthalmopathy, and suggest instead that T and B cell autoreactivity to striated muscle antigens is a frequent feature of autoimmune thyroid disease, unlikely to be directly related to eye disease.

Electrophoretic assessment of aqueous and serum neurone-specific enolase in retinoblastoma and ocular malignant melanoma.

The isoenzyme pattern of enolase was examined in the aqueous humour and serum of patients with retinoblastoma (10 aqueous, 8 sera), malignant melanoma (4 aqueous, 25 sera), and normal subjects undergoing cataract surgery (25 aqueous, 30 sera). The assay we used allowed assessment of all three major isoenzymes, including the gamma gamma isoenzyme (neurone-specific enolase). No enolase was detectable in normal aqueous; alpha alpha isoenzyme was present in the aqueous of one patient with malignant melanoma, while aqueous from all patients with retinoblastoma contained both alpha alpha and gamma gamma. Normal serum contained only an alpha alpha band, while serum from patients with retinoblastoma contained alpha alpha, alpha gamma, and gamma gamma bands (7 sera, 87.5%), or alpha alpha only (1 patient, 12.5%). All sera from patients with malignant melanoma contained the alpha alpha band, with low levels of gamma gamma in 16 (60%). In a single patient with Coats's disease alpha alpha was present in the serum, but no enolase was detected in aqueous. Increased amounts of gamma-containing isoenzymes of enolase are found in both serum and aqueous from patients with retinoblastoma. In malignant melanoma there is often an increase in serum gamma gamma enolase. The assessment of aqueous and serum enolase patterns may be of value in the diagnosis of retinoblastoma and malignant melanoma.