Anaemia of chronic disease (ACD) is a frequent complication of rheumatoid arthritis (RA). A diagnostic difficulty in RA is the distinction between iron deficiency anaemia (IDA) and ACD. The aim of our study was to evaluate the usefulness of serum soluble transferrin receptor (sTfR) and sTfR/log ferritin (TfR-F) index to diagnose iron deficiency in RA patients with anaemia. Routine laboratory indices of anaemia and sTfR were measured in 20 healthy persons to form the control group, 30 patients with iron deficiency anaemia and 28 RA patients with anaemia. Serum sTfR levels were significantly elevated above the cut-off value in patients with IDA and those in the iron depleted RA subgroup (ferritin < 60 microg/L) compared with those in the control and iron repleted RA subgroup (ferritin > 60 microg/L). The same was observed for TfR-F index. However, five patients in the iron repleted RA sub group had an elevated sTfR level, of which two had increased TfR-F index. Serum sTfR correlated well with the markers of anaemia and not with ESR. Ferritin had no correlation with markers of anaemia but correlated well with ESR. Measurement of sTfR and TfR-F index are good indicators of iron deficiency in RA patients with anaemia. To be cost effective, sTfR can be estimated in RA patients with anaemia when the ferritin level is more than 60 microg/L.
Serumosmolality measured by cryoscopic techniquein laboratory is the reference method.In clinical settings,serum osmolality measurement is notfeasible at bedside. In normal subjects, sodium, potassium glucose, and urea are the primary circulating solutes. These solute concentrations can be used to predict measured osmolality if no other solutes present at high millimolar concentrations.Many equations of serum osmolality have been proposed. The osmolal gap (OG) is the difference between measured osmolality and calculated osmolality.The major use of OG is to screen for presence of exogenous toxic substances and to screen alcohol intoxicationcases.Aim/Objective: The purpose of this study was to compare the calculated osmolality using various formulaewith the measured osmolality to determine which calculated formula fit best with measured osmolality.Materials and Methods: Serum osmolality resultsfromJanuary 2015 to December 2015 were extracted from the laboratory information system (LIS). Serum osmolality performed simultaneously with renal and liver function tests, serum electrolytes and plasma glucose were included.Serum osmolality measured for patients with the history of drug abuse and poisoning were excludedfrom the study.405serum osmolality results were chosen and divided into two groups. Group 1 included 205data with normal serum osmolality, renal, liver function tests and plasma glucose level less than 7.8 mmol/L.For the second group (n=200), data with low serum osmolality (n=90) and high serum osmolality (n=80) and normal serum osmolality (n=30) were included. Group 1 data was to identify which equation correlated with the measured osmolality and the Group 2 datato study the performance of equationthat correlated with the measuredosmolality.Results: Only four out of19 formulae were identified as optimal by havingthemean OG ≤ 2 mOsm/kg. The Smithline-Gardner formula (2Na+ Glu + BUN) showed the smallest osmolal gap with mean bias 0.3mOsm/kg. The Dorwart-Chalmers formulaincorporated in most autoanalysers for calculation of osmolalityunderestimatedcompared to measured osmolality.Conclusion: We recommend Smithline-Gardner formula for calculation of osmolal gap, as the OG gap is close to zero, simple, easy to calculate at bedside and easily incorporated in the Laboratory Information System.
The tumour marker CA19-9 is a sensitive marker for pancreatic, gastric and hepatobiliary malignancies. High CA 19-9 level indicates unresectable lesions and a poor prognosis. The objective of the study was to determine the significance and implications of elevated CA 19-9 levels in the serum. A one-year retrospective review of all patients who had CA19-9 measured in our Medical Centre was undertaken; 69 patients were found to have CA 19-9 level above the cut-off value (37 U/ml). Thirty-six patients had malignant and the remaining 33 had benign lesions. CA 19-9 was found to be elevated in malignancies of pancreas, colorectum, lung, liver and ovary. Benign conditions associated with elevation of CA 19-9 included disease of the hepatobiliary system, pneumonia, pleural effusion, renal failure and SLE. In two individuals, there was no obvious cause for the elevation of this marker. CA 19-9 levels were significantly lower in benign than in malignant conditions. In conclusion, elevated CA 19-9 may be found in patients with benign as well as malignant disease. Therefore, it is important (1) that elevated levels of CA 19-9 are interpreted in the light of the clinical presentation of the patient and (2) to be aware of the benign conditions that can be associated with increased levels of this marker. With these factors in mind, CA 19-9 can be used to assist in the diagnosis of pancreatic cancer and assessment of resection adequacy post-operatively.
Aim: Autoantibodies against cyclic citrullinated peptide (anti-CCP) are considered to be a sensitive and specific marker for rheumatoid arthritis (RA). This study evaluated the diagnostic and analytical performances of the automated anti-CCP assay.
Materials and Method: Sera from 80 patients with established RA, 65 from other rheumatic diseases (non-RA) and 55 from healthy controls were studied using second generation anti-CCP. Rheumatoid factor (RF) was also assayed in each sample, and the results were compared to the anti-CCP fi ndings. Serum pools were used to determine the precision and linearity.
Results: At a cut-off of 7.4 U/ml for anti-CCP, the sensitivity and specificity for RA were 65% and 98% respectively. RF had a sensitivity of 58% and a lower specifi city of 93 % than anti-CCP. Conclusion: The high specificity of the assay suggests that anti-CCP is useful in the diagnosis of rheumatoid arthritis and in our cohort of study population anti-CCP exhibits a better diagnostic value than RF. A considerable proportion (28%) of RF-negative RA patients were anti-CCP positive. Based on analytical performance of the assay, we conclude that full automation and high throughput features of AxSYM makes it an ideal platform for routine testing of anti-CCP.
Study site: Rheumatology clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia