A Cohort Study of Free Light Chain Ratio in Combination with Serum Protein Electrophoresis as a First-Line Test in General Practice.

Multiple Myeloma (MM) often present with unspecific symptoms, which can lead to diagnostic delay. Serum-free light chain (sFLC) ratio is suggested to replace urine protein electrophoresis (UPE) in the diagnostic work-up of myeloma. We aimed to investigate the performance of the sFLC-ratio in general practice (GP) compared to UPE, just as we explored different sFLC-ratio cut-offs' influence on diagnostic values. In a cohort of 13,210 patients from GP measures of sFLC-ratio, serum protein electrophoresis (SPE), or UPE were compared to diagnoses of incident M-component related diseases acquired from Danish health registers. UPE and sFLC-ratio equally improved diagnostic values when combined with SPE (sensitivity: SPE and UPE: 95.6 (90.6-98.4); SPE and sFLC-ratio: 95.1 (90.2-98.0)). The addition of the sFLC-ratio to SPE resulted in the identification of 13 patients with MGUS, light chain disease and amyloidosis, which was in line with the addition of UPE to SPE. The number of false-positive tests was UPE and SPE: 364 (11%) and sFLC-ratio and SPE: 677(19%). Expanding sFLC-ratio reference range to 0.26-4.32 resulted in a significant reduction in false positives n = 226 (6%) without loss of patients with clinical plasma cell dyscrasias. sFLC-ratio improves the diagnostic value of SPE in GP. However, due to low specificity and a large number of false positives, expanded cut-off values should be considered.

Serum levels of IgG antibodies against Aspergillus fumigatus and the risk of hypersensitivity pneumonitis and other interstitial lung diseases.

Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) caused by the inhalation of antigens. Antigen-specific IgG antibodies (sIgG) are used as biomarkers of exposure when diagnosing HP, but little is known about the longitudinal relation between antibody levels and risk of HP or other ILD. In a follow-up design, we explored the relationship between sIgG antibodies against Aspergillus fumigatus and the diagnosis of HP in 647 subjects suspected of HP. We showed that IgG levels above the reference value resulted in a hazard ratio of 9.5 for subsequent HP. Our findings support a relationship between high levels of sIgG against A. fumigatus and risk of HP.

The use of allergen-specific IgE tests in general practice.

INTRODUCTION: In Denmark, diagnosing and treating allergy is mainly performed by general practitioners (GPs), but precise expectations of the GPs are not described in guidelines. Furthermore, very little is known about GPs' use of allergen-specific immunoglobulin E (sIgE) tests. The aim of this study was to describe the use of these tests in the Central Denmark Region. METHODS: We performed analyses on data from all sIgE tests ordered by GPs in the Central Denmark Region in 2015. A test was considered positive if the serum level of IgE was ≥ 0.35 kU/l. RESULTS: Serum levels of sIgE were determined in 26,129 patients, equivalent to 2% of the Danish population. A total of 106,237 tests were performed, the majority as part of screening algorithms for inhalant and food allergens. Screening was ordered 20,697 times for inhalation allergens and 12,999 times for food allergens. Additionally, a considerable number of tests for antibiotics (n = 4,407), insect venom (n = 748) and other allergens were performed (n = 824). Positive rates were determined for various allergens in relation to gender and age. The rates were generally higher than rates known to be present in the background population. A higher percentage of females than males was tested. However, positive rates were generally lower in females than in males. CONCLUSIONS: This is the first descriptive analysis of the use of testing for sIgE in general practice. Results from this study may be used to optimise how GPs order and interpret sIgE tests in the future. FUNDING: none. TRIAL REGISTRATION: not relevant.

Whole blood samples for adrenocorticotrophic hormone measurement can be stored at room temperature for 4 hours.

INTRODUCTION: The aim of this study was to investigate and compare the stability of adrenocorticotrophic hormone (ACTH) in whole blood stored on ice and at room temperature for up to 48 hours. This study differs from previous studies by a larger data material. MATERIALS AND METHODS: EDTA-blood samples from 30 patients were collected, aliquoted and stored on ice or at room temperature for 0, 2, 4, 24, or 48 h before centrifugation, and the plasma was stored frozen until analysis. All samples were analyzed using an automated electrochemiluminescence immunoassay on cobas 6000 e601. The change in ACTH concentration was illustrated as ACTH recovery compared to standard conditions defined as samples stored immediately on ice, centrifuged and plasma frozen within 1 h. A change in ACTH concentration of more than 10% was considered to be of clinical relevance. RESULTS: The results showed no clinically relevant change in ACTH recovery for up to 4 h compared to standard conditions. For samples stored at room temperature for 4 h, a significant (p < .0001) relative mean change in ACTH concentrations of -4.3% was observed. CONCLUSION: The comparison between samples stored at room temperature for up to 4 h and standard conditions showed that ACTH samples do not require cooling until centrifugation, if a mean difference in ACTH concentration of -4.3%, between the individual results, can be accepted.

Quantitative measurements of trefoil factor family peptides: possibilities and pitfalls.

The trefoil factor family (TFF) peptides TFF1, TFF2, and TFF3 are produced and secreted by mucous membranes throughout the body. Their importance for the protection and repair of epithelial surfaces is well established, and the three peptides are present in various amounts in mucosal secretions as well as in the circulation. They have been linked to both inflammatory diseases and to various types of cancer, and serum concentrations of TFF3 show a more than 47-fold increase during pregnancy. Several both commercial and in-house immunoassays exist, but a number of methodological issues remain unresolved. This review describes methodological challenges in the measurement of the peptides in humans, and summarizes current knowledge concerning the occurrence and possible significance of the peptides in human health and disease.

Trefoil factors in saliva and gingival tissues of patients with chronic periodontitis.

BACKGROUND: Trefoil factors (TFFs) are secreted molecules that are involved in cytoprotection against tissue damage and the immune response. TFFs have been detected in saliva and oral tissues, but their clinical significance has never been investigated in patients with chronic periodontitis. The objective of this study is to determine whether TFF expression in saliva and gingival tissues is associated with periodontal pathology. METHODS: Saliva and gingival tissue samples were collected from 25 non-periodontitis individuals and 25 patients with chronic periodontitis (CP). Enzyme-linked immunosorbent assay and immunohistochemical methods were used to evaluate the expression of TFFs (TFF1, TFF2, and TFF3) in saliva and gingival tissues, respectively. Periodontopathic bacteria were quantified by real-time polymerase chain reaction. RESULTS: Reduced salivary TFF1 and TFF3 concentrations were observed in patients with CP (P = 0.003 and P <0.001, respectively). Decreased TFF3 expression in gingival tissues of patients with CP was demonstrated (P = 0.041). Levels of salivary TFF3 concentrations were negatively correlated with periodontal pathology and number of Porphyromonas gingivalis and Tannerella forsythia (formerly known as Bacteroides forsythus). CONCLUSIONS: Altered expression of TFFs in saliva and gingival tissues was detected in patients with CP. The results suggest that TFF3 may be involved in the pathogenesis of periodontal disease.

Investigation of trefoil factor expression in saliva and oral mucosal tissues of patients with oral squamous cell carcinoma.

OBJECTIVES: The aims of our study were to determine levels of trefoil factor (TFF) peptides in saliva and oral mucosal tissues from patients with oral squamous cell carcinoma (OSCC), and to evaluate whether individual members of TFFs (TFF1, TFF2, and TFF3) might act as biomarkers of disease. MATERIALS AND METHODS: Saliva samples were from 23 healthy subjects and 23 OSCC patients. Tissue samples were collected from 32 normal oral mucosa (NOM) and 32 OSCC biopsy specimens. ELISA and immunohistochemical methods were used to evaluate the expression of TFF1, TFF2, and TFF3 in saliva and oral mucosal tissues, respectively. RESULTS: Expression of TFF2 and TFF3 in oral mucosal tissues of OSCC patients was strongly downregulated when compared to healthy subjects (p < 0.001 and p = 0.002, respectively). However, there were no differences in levels of salivary TFF concentrations between OSCC patients and healthy subjects. CONCLUSIONS: The present study extends previous observations, demonstrating the reduction of TFF2 and TFF3 expression in oral mucosal tissues of OSCC patients. CLINICAL RELEVANCE: These findings suggest the clinical significance of TFF2 and TFF3 molecules as negative markers of tumor progression in OSCC. Quantification of TFF levels in saliva may not be optimal in terms of diagnostic or predictive value for OSCC derived from oral mucosa.

Trefoil factor family peptides in human saliva and cyclical cervical mucus. Method evaluation and results on healthy individuals.

BACKGROUND: Trefoil peptides are 7-12 kDa molecules, se-creted by a variety of mucin-producing epithelial cells from different tissues and believed to be essential for protection and maintenance of gastrointestinal mucosa. Data on concentrations of trefoil peptides in secretions are limited. METHODS: We validated in-house ELISA assays, developed for measurement of trefoil peptide concentrations (TFF1, TFF2 and TFF3) in serum, for use with saliva and cervical mucus. Saliva from healthy individuals (n=30), and cervical mucus as well as blood collected three times during the menstrual cycle from healthy women (n=18) were analyzed. RESULTS: Recovery of all trefoil peptides in the initial supernatants of saliva and (cervical mucus) were 86 and (92)% or more. Recovery of exogenously added trefoil peptides was 93 and (95)% or more. Western blotting showed that antibodies used in the TFF3-ELISA assay recognised one molecule of the same size as TFF3 in both saliva and cervical mucus. Median concentrations of TFF1, TFF2 and TFF3 in saliva and (cervical mucus) were 2.7 (2.7), 0.08 (0.58) and 14 (430) nmol/g protein, with a significant decrease in concentrations in cervical mucus after ovulation. Serum concentrations resembled previously measured values in blood donors and showed no cyclic change. CONCLUSIONS: Previously established ELISA assays can be employed for measurement of trefoil peptides in saliva and cervical mucus. TFF3 was the predominant trefoil peptide in both saliva and cervical mucus, and TFF3 in cervical mucus represents the highest concentration measured in a biological fluid to date.