The prevalence and significance of nonuniform thyroid radio-isotope uptake in patients with Graves' disease.

OBJECTIVE: To evaluate the prevalence and clinical significance of nonuniform technetium (99m Tc) uptake among patients with Graves' disease (GD). DESIGN, PATIENTS AND MEASUREMENTS: Patients with GD, referred between July 2005 and March 2018, had Tc99 - uptake scans and TSH-receptor antibody (TRAb) measured before antithyroid drug (ATD) therapy. Risk of relapse after ATD cessation was monitored until June 2021 and compared between GD patients based on uptake patterns. RESULTS: Of the 276 GD patients (mean age, 49.8 years; 84% female), 25 (9.0%) had nonuniform Tc99 uptake. At diagnosis, individuals with nonuniform uptake were older (mean age of 61.8 vs. 48.5 years, p < .001), had lower mean thyroid hormone levels (free thyroxine: 36.3 vs. 45.4 pmol/L, p = .04 and free triiodothyronine: 10.0 vs. 17.8 pmol/L, p < .001) and median TRAb levels (4.2 vs. 6.6 U/L, p = .04) compared with those with a uniform uptake. Older age was a significant predictor for the presence of nonuniform uptake in GD patients; odds ratio (95% confidence intervals) of 1.07 (1.03 - 1.10). The risk of relapse was similar in both groups after a median (IQR) follow-up of 41 (13-74) months after ATD cessation (56.0% vs. 46.3%, respectively); hazard ratio (95% confidence intervals) of 1.74 (0.96-3.15). CONCLUSIONS: Nonuniform radio-isotope uptake is seen in 1 in 11 patients with GD which could be misdiagnosed as toxic multinodular goitre if TRAb levels are not measured. Treatment of GD patients with nonuniform radio-isotope uptake with ATD therapy as first-line appears to be equally effective as compared with those with uniform uptake. TRAb testing should be the main diagnostic test for patients with suspected GD with radio-labelled uptake scans being reserved for those who are TRAb negative.

Variation in the reference range limits of thyroid function tests and association with the prevalence of levothyroxine treatment.

Many individuals with marginally abnormal thyroid function test (TFT) results may be treated and it is unknown if the limits of the thyrotropin (TSH) and free thyroxine (FT4) reference intervals reported alongside the laboratory results are associated with the prevalence of levothyroxine treatment. We obtained information regarding reported TFT reference intervals from UK National Health Service (NHS) laboratories and evaluated its relationship with the prevalence of levothyroxine treatment for corresponding health areas for 2014. The upper limit of serum TSH was significantly, linearly, independently, and negatively associated with prevalent levothyroxine treatment: -0.54% (95% CI, -0.68% to -0.40%). The lower limit of serum FT4 was significantly and independently associated with the prevalence of levothyroxine treatment in a non-linear (J-shaped) manner with an increase being noted from a FT4 level of ≈9.5 pmol/L onwards. We conclude that minor changes in the reference range limits for serum TSH and FT4 are associated with levothyroxine treatment.

Embedding assessment of liver fibrosis into routine diabetic review in primary care.

BACKGROUND & AIMS: Individuals with type 2 diabetes (T2DM) are at high risk of developing non-alcoholic fatty liver disease (NAFLD) and advanced fibrosis/cirrhosis. Screening patients with T2DM and normal liver enzymes for NAFLD in primary care remains contentious. Our aim was to develop and assess a primary care pathway integrating two-tier (Fib-4 then transient elastography [TE]) liver fibrosis assessment, irrespective of aetiology, into routine annual review of all patients with T2DM. METHODS: All patients aged >35 years with T2DM attending annual review at 2 primary care practices in North East England between April 2018 and September 2019 (n = 467) had Fib-4 requested via the electronic patient record. Those with a Fib-4 score above the 'high-sensitivity' threshold (>1.3 for ≤65 years and >2.0 for >65 years) underwent TE and were reviewed in secondary care if the liver stiffness measurement (LSM) was >8 kPa. The number of patients identified with advanced disease, service uptake, and predictors of advanced disease were assessed. RESULTS: A total of 85/467 (18.5%) patients had raised Fib-4; 27/467(5.8%) were excluded as a result of frailty or known cirrhosis. A total of 58/467 (12.2%) were referred for TE. Twenty-five of 58 (43.1%) had an LSM of >8 kPa and 13/58 (22.4%) had an LSM >15 kPa; 4/58 (6.7%) did not attend and 5/58 (9.3%) had an invalid reading. Twenty of 440 (4.5%) patients were found to have advanced liver disease following specialist review, compared to 3 patients previously identified through standard care (odds ratio [OR] 6.71 [2.0-22.7] p = 0.0022). Alcohol (OR 1.05 [1.02-1.08] p = 0.001) and BMI (OR 1.09 [1.01-1.17] p = 0.021) were predictors of advanced disease, particularly drinking >14/21 units/week (p <0.0001). CONCLUSIONS: Incorporating 2-tier assessment of liver fibrosis into routine annual diabetes review in primary care significantly improves identification of advanced liver disease in patients with T2DM. LAY SUMMARY: People with type 2 diabetes are at increased risk of developing non-alcoholic fatty liver disease and developing more significant complications. This study looks at introducing screening for advanced liver disease into the annual diabetes reviews performed routinely in primary care; we found that significantly more people were identified as having significant liver disease through this pathway than with current standard care.

Enhanced immunogenicity of CTL antigens through mutation of the CD8 binding MHC class I invariant region.

CD8(+) cytotoxic T lymphocytes (CTL) are key determinants of immunity to intracellular pathogens and neoplastic cells. Recognition of specific antigens in the form of peptide-MHC class I complexes (pMHCI) presented on the target cell surface is mediated by T cell receptor (TCR) engagement. The CD8 coreceptor binds to invariant domains of pMHCI and facilitates antigen recognition. Here, we investigate the biological effects of a Q115E substitution in the alpha2 domain of human leukocyte antigen (HLA)-A*0201 that enhances CD8 binding by approximately 50% without altering TCR/pMHCI interactions. Soluble and cell surface-expressed forms of Q115E HLA-A*0201 exhibit enhanced recognition by CTL without loss of specificity. These CD8-enhanced antigens induce greater CD3 zeta chain phosphorylation in cognate CTL leading to substantial increases in cytokine production, proliferation and priming of naive T cells. This effect provides a fundamental new mechanism with which to enhance cellular immunity to specific T cell antigens.