Evaluation of the (14)C-urea breath test using indigenously produced (14)C-urea capsules and a modified technique for trapping exhaled breath: a pilot study.

The carbon urea breath test ((14)C-UBT) is a noninvasive technique used to detect Helicobacter pylori infection in patients presenting with dyspeptic symptoms. The present study was undertaken to determine the efficacy of indigenously produced (14)C-UBT capsules by the Board of Radiation and Isotope Technology, India. Thirty consecutive patients with dyspeptic symptoms were included in the study. After ingestion of capsules, breath samples were collected in a CO2-trapping solution to which a scintillation cocktail was added. After 24 h, the whole sample was counted in a liquid scintillation counter along with a standard of (14)C. The number of disintegrations of (14)C per minute in the breath sample was calculated. The results were compared with histopathological reports. Of 30 patients, 19 were positive and 11 were negative on (14)C-UBT. Histopathological reports confirmed 27 cases as positive and three as negative for H. pylori. Thus, the results of (14)C-UBT were concordant with histopathological results in 22/30 (73.3%) cases. Considering histopathology as the gold standard, the sensitivity, specificity, and positive predictive value of (14)C-UBT using indigenously produced capsules were found to be 70.33, 100, and 100%, respectively. On critical analysis of the discordant results, we observed that six patients had undergone H. pylori eradication therapy exactly 4 weeks before the test. When these six patients were excluded from the analysis, the sensitivity, specificity, and positive predictive value were found to be 90.05, 100, and 100%, respectively, which compared well with the values obtained using the standard procedure. The study demonstrates adequate efficacy of the indigenous methodology in newly diagnosed symptomatic patients with acid peptic disorders. The analyses of the results indicate that the test should be preferably employed after the recommended period of 1 month following completion of eradication therapy.

Estimation of sacroiliac joint index in normal subjects of various age groups: comparative evaluation of four different methods of quantification in skeletal scintigraphy.

BACKGROUND: To estimate and compare the sacroiliac joint (SIJ) index in skeletal scintigraphy by four different methods of quantification employed in normal subjects of different age groups. MATERIAL AND METHODS: The whole-body skeletal survey of 100 subjects, who underwent skeletal scintigraphy three hours after injection of 99mTc-Methylene Diphosphonate (MDP), were selected for this analysis. The patients having previous history of low back pain, joint pain or any benign bone joint disorders (e.g. ankylosing spondylitis, metabolic bone disease, and osteoarthritis), documented bone lesions or tumors within the pelvis region were excluded from the study. All subjects had normal posterior pelvis view on visual assessment in the respective study. Sacroiliac joint index was calculated by quantitative sacroiliac scintigraphy. In each subject, four different methods of quantification were carried out: 1. irregular region of interest (ROI) method, 2. rectangular ROI method, 3. profile peak counts (PPC) method and 4. profile integrated counts (PIC) method and applied to calculate SIJ index. SIJ indices for left and right sacroiliac joints were calculated by dividing the count for each joint by the count for the sacrum. Results obtained by the four methods were compared statistically. RESULTS: The overall SIJ index was found to range from 1.06 to 1.36 in the study population of 100 subjects encompassing all age groups. There was no significant difference in the estimated SIJ index within each age group obtained by the four different methods employed in this study. The values of SIJ index were as follows: in patients aged 2-20 years - they ranged from 1.22 to 1.36; in patients aged 21-40 years - from 1.07 to 1.19; for patients aged 41-60 years - from 1.08 to 1.19 and in patients aged 61 years and older, SIJ values were slightly lower than in other groups and ranged from 1.06 to 1.13. CONCLUSION: Methods of selecting a region of interest have no significant effect on the calculation of SIJ index and in healthy subjects its values range between 1.06 and 1.36, depending on the age of the subject. The maximum value was observed in patients aged 2-20 years and minimum values were noted in patients aged 61 and older.

A Comparative Study of Bone Scan Findings and Serum Levels of Tumor Marker CA15-3 in Patients with Breast Carcinoma.

Breast cancer is one of the most frequent malignancies in the world. Available staging procedures to detect breast cancer are bone scan, chest X-ray, liver ultrasonography, computerized tomography, estimation of tumor markers like carbohydrate antigen (CA15-3) and carcino embryonic antigen. These procedures are expensive and may not be required in all cases. Out of 70 patients studied, 55 had normal CA15-3 and 15 had elevated levels of Ca15-3. Eight (14.5%) of the 55 patients with normal CA15-3 had abnormal bone scan. Fifteen patients had CA15-3 levels above the normal range and among these 9 (60%) had abnormal bone scan. While prime facie it would appear that a high level of CA15-3 correlate with abnormal bone scan, it is also true that the numbers are small at present and conclusions about the validity of CA15-3 as marker of bone metastasis may be premature.

Myocardial uptake of F-18-fluorodeoxyglucose in whole body positron emission tomography studies.

PURPOSE: The objective of this study was to correlate the degree of myocardial fluorodeoxyglucose (FDG) uptake in routine oncology positron emission tomography (PET) studies with fasting blood sugar level (FBSL), fasting period (FP) and age of the patient. MATERIALS AND METHODS: Ninety-one patients (62 males and 29 females, age range: 7-78 years) with malignant diseases were included in the study. Whole body FDF-PET study was carried out after 1 h of intravenous injection of 296-370 MBq (8-10 mCi) F-18 FDG. Images were interpreted visually and patients were classified into four grades of myocardial uptake: No myocardial uptake = Grade 0; mild uptake = Grade 1; moderate uptake = Grade 2; and Marked uptake = Grade 3. Quantitative analysis was done by calculating Standardized uptake value (SUVmax). Age, FBSL and FP were recorded. RESULTS: Thirty-seven (41%) patients showed no uptake in myocardium (Gr-0). Mean FP, FBSL and age was 14 h, 94.19 mg% and 44.3 years respectively. Eleven (12%) cases were rated as Grade 1, 27 (30%) as Grade 2 and 16 (17%) as Grade 3. The mean values of FP, FBSL and age were 12.9 h, 96.55 mg% and 43.54 years for Grade 1, 13.48 h, 87.11 mg% and 40.85 years for Grade 2 and 13.37 h, 86.56 mg% and 36.18 years for Grade 3 respectively. SUVmax was found to vary between 1 and 22. It was observed that 47% (Grade 2 and 3) patients had significant cardiac FDG uptake in spite of blood sugar levels 71-125 mg%. CONCLUSION: The degree of myocardial FDG uptake did not show significant correlation with FBSL, FP or age of the patient. Perhaps the reason lies elsewhere like insulin levels, medical treatments, fat metabolism, and myocardium status or some unexplored factors.

Asymmetric 18F-FDG Uptake in the Infradiaphragmatic Brown Adipose Tissue (BAT) Mimicking Adrenal Metastasis: A Relatively Rare Site of Brown Fat and a Potential Source for False Positive FDG-PET Study.

FDG uptake in the metabolically active brown adipose tissue (BAT) is a source of significant concern while interpreting FDG-PET studies. It is also of great interest due to its potential implications for obesity research. In this communication, we describe hitherto unreported asymmetric BAT uptake in the abdomen, persisting after diazepam intervention in the repeat PET study on a separate day. The patient did not have any evidence of disease even at 24 months' follow up. The present case is a useful addition to the current body of literature of false positive FDG-PET due to BAT uptake in unusual location and underscores the importance of high index of suspicion and careful correlation, whenever one comes across an unusual PET finding in a given clinical situation. This assumes important diagnostic value particularly when it coexists in the setting of malignancy where the disease can be falsely upstaged by misinterpretation. The literature relevant to the report is discussed and a schema is suggested for correct interpretation.