Rebecca Abraham

Interference of anti-T3 autoantibodies in the measurement of total and free T3 in serum.

A case of anti-trilodothyronine autoantibodies is presented in this report. The thyroid hormone profile of a hypertensive patient, with multinodular goiter and history of exogenous thyroid hormone therapy, was found to be highly ambiguous. The total as well as free T3 levels were consistently high (out of range) whereas the T4 (total and free) values were always within normal limits. The thyrotropin was found to be partially suppressed. Very low T3-Uptake indicated some kind of interference in the immunoassays. We incubated the sera with the radio-iodine labelled T3 and observed that the patients serum bound about ten times more radioactivity than a control run in parallel. On further resolving the serum proteins on cellulose acetate electrophoresis, the radioactivity was detected in the γ-globulin band. Therefore it was established that the patients serum carried the antibodies reactive with T3 which were interfering in the immunoassays. Elevated anti-thyroid microsomal antibodies were also present in the patients serum. The anti-T3 antibodies were highly specific for T3 and did not show any cross reactivity with the T4 or its analogues used in the estimation of free T4.

δ-ALA levels in serum and urine—A diagnostic tool for possible lead poisoning

We present 2 cases of lead poisoning, the first of a child playing with painted toys and the second of an adult on local medicine. The former presented with acute abdomen and the latter with peripheral muscle weakness. We propose that raised serum δ-amino leavulinic acid (δ-ALA) levels strongly point towards the possibility of lead poisoning.

Serum Lysozyme (Muramidase) Levels in Intra-Abdominal Abscesses: An Experimental Study

The role of serum lysozyme in the presence of intra-abdominal sepsis was studied to act as an adjunct to various other modalities used for diagnosing intra-abdominal abscesses. Lysozyme (muramidase) is a bacteriolytic enzyme located within phagocytic cells including leukocytes. We measured serum concentrations of lysozyme by a standard turbidimetric method on three groups of murine models. One group underwent caecal ligation and puncture (CLP), the second group underwent a sham operation, and the third group was used as controls. In mice with intra-abdominal abscesses secondary to caecal ligation and perforation (n = 30), the serum lysozyme levels were increased compared to the sham-operated mice (n = 30) and controls (n = 30) (p = <0.001). In this study, serum lysozyme levels have a high sensitivity and specificity related to the presence of an intra-abdominal abscess in mice. Clinical studies are required to demonstrate its role in humans.

Quantification of Coronary Risk Score

Objective : To quantify the coronary risk score in children and/or grandchildren of patients with coronary artery diseae (CAD).Methods : One hundred and fifty children with positive family history of CAD (cases) and age and sex matched children with no such history (controls) were enrolled in the study. Fasting blood sugar, serum cholesterol and triglycerides were estimated on all children and a risk score was calculated using Nora’s scheme.Result : The cases and controls were similar with respect to mean age, six distribution, mean weight and mean height. None of the child was hypertensive. Mean serum levels of triglycerides were 164.7 m/dl and 105.7 mg% respectively in cases and controls (p<0.005). Prevalence of hypertriglyceridemia was three times more in cases (p<0.001). Cases had a significantly higher risk scores (p<0.00001) and this was mainly attributable to higher biochemical risk (P<0.0006).Conclusion : Children and grand children with a positive family history of CAD had significantly higher risk scores for future CAD. The increased risk was mainly due to biochemical derangements.

Interference of anti-T4 autoantibodies in the single step free T4 radioimmunoassays.

The thyroid hormone profile of a hypothyroid patient, with moderate sized diffuse goiter and history of exogenous thyroid hormone therapy, was found to be highly ambiguous. The total as well as free T4 levels were consistently high (out of range) with suppressed T3 (total and free) and elevated thyrotropin levels. We incubated the serum with the radio-iodine labelled T4 and observed that the patient’s serum bound about 50.5% of the total radioactivity resulting in 85.3% interference in the radioimmunoassay. On resolving the serum proteins by cellulose acetate electrophoresis, the radioactivity was detected in the gamma globulin band. The protein profile showed mildly raised levels of IgG. Therefore it was established that the patient’s serum carried T4 reactive antibodies (IgG) which were interfering in the immunoassays. Elevated anti-thyroid microsomal antibodies were also present in the patient’s serum. The anti-T4 antibodies were highly specific for T4 and did not show any cross reactivity with the T3 or its analogues used in the estimation of free T3. We stripped the serum by precipitating the immunoglobulins and were successful in estimating the levels of free T4 in the stripped serum by single step radioimmunoassy.

Polymerase chain reaction: It’s diagnostic application

The development of the Polymerase Chain Reaction (PCR) has been a major technical milestone in molecular genetics with the greatest impact on research, in rapid medical diagnosis and in studying the pathogenesis of disease. This study highlights the practical applications of polymerase chain reaction in diagnosis and includes a recent application of PCR in differentiating polio from other nonpolio enteroviruses.