Possible Role of Meckel's Scan Fused with SPECT CT Imaging: Unraveling the Cause of Abdominal Pain and Obscure-Overt Gastrointestinal Bleeding

A 27-year-old male presented with recurrent abdominal pain and high volume hematochezia despite undergoing extensive testing and a right hemicolectomy 3 years prior for a linear bleeding ulceration in the ascending colon. Studies at the University of Michigan included esophagogastroduodenoscopy (EGD), colonoscopy and video capsule endoscopy (VCE), revealing an arteriovenous malformation (AVM) in the terminal ileum. He was hospitalized for recurrent symptoms. His presentation suggested a small bowel source of obscure-overt GI bleeding based on prior non-diagnostic colonoscopy and EGD and a bilious nasogastric lavage. Tagged red blood cell scan localized bleeding to the right lower quadrant. Colonoscopy showed fresh blood in the terminal ileum without a clear source. Angiography showed no evidence of bleeding or terminal ileal AVM. A novel Meckel's scan fused with SPECT imaging showed focal uptake in the terminal ileum. The patient underwent Meckel's diverticulectomy with sparing of adjacent bowel and has remained asymptomatic for 19 months. This case illustrates that patients with obscure-overt GI bleeding require a step-wise multi-modality diagnostic work-up. Because Meckel's scans are false-positive in 28% of adults, Meckel's scan fused with SPECT imaging may offer an approach to refine diagnostic accuracy of either scan alone, but requires further investigation. Exploratory laparotomy should be reserved as a last option and is best performed with intraoperative endoscopy

Feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi protocol

Aim of the present study was to investigate the feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi dose protocol compared to conventional "high 740 MBq (20 mCi) (99m)Tc-sestamibi dose protocol" in patients with primary hyperparathyroidism (PHPT). The data of focused radioguided surgery obtained in a group of 320 consecutive PHPT patients with high probability of the presence of a solitary parathyroid adenoma (PA) were studied. All patients underwent preoperative imaging work-up of double-tracer (99m)Tc-pertechnetate/(99m)Tc-sestamibi subtraction parathyroid scintigraphy (Sestamibi scintigraphy) and high resolution neck ultrasound (US). In 301/320 patients (96.6%) focused minimally invasive radioguided surgery was successfully performed by administering a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi dose in the operating room 10 minutes before operation. No major intraoperative complications were recorded. Focused radioguided surgery required a mean time of 32 min and a mean hospital stay of 1.2 days. Local anesthesia was applied in 75 patients, 66 of whom (88%) were patients older than 65 years with comorbidities contraindicating general anesthesia. No case of persistent or recurrent PHPT was observed during post-surgical follow-up (range = 18–70 months; mean +/- SD = 15.3 +/- 9.1 months). Radiation exposure dose to the operating surgeon was 1.2 μSi/hour with the "low 37 MBq (1 mCi) (99m)Tc-sestamibi dose", and less than 1.0 μSi/hour for the other operating-room personnel. Focused low dose radioguided parathyroidectomy is a safe and effective means to localize parathyroid adenomas in patients affected by solitary PA thus reducing by 20 fold the radiation exposure dose to the patients and operating room personnel

Further investigation of confirmed urinary tract infection (UTI) in children under five years: a systematic review.

Background: Further investigation of confirmed UTI in children aims to prevent renal scarring and future complications. Methods: We conducted a systematic review to determine the most effective approach to the further investigation of confirmed urinary tract infection (UTI) in children under five years of age. Results: 73 studies were included. Many studies had methodological limitations or were poorly reported. Effectiveness of further investigations: One study found that routine imaging did not lead to a reduction in recurrent UTIs or renal scarring. Diagnostic accuracy: The studies do not support the use of less invasive tests such as ultrasound as an alternative to renal scintigraphy, either to rule out infection of the upper urinary tract (LR- = 0.57, 95%CI: 0.47, 0.68) and thus to exclude patients from further investigation or to detect renal scarring (LR+ = 3.5, 95% CI: 2.5, 4.8). None of the tests investigated can accurately predict the development of renal scarring. The available evidence supports the consideration of contrast-enhanced ultrasound techniques for detecting vesico-ureteric reflux (VUR), as an alternative to micturating cystourethrography (MCUG) (LR+ = 14.1, 95% CI: 9.5, 20.8; LR- = 0.20, 95%CI: 0.13, 0.29); these techniques have the advantage of not requiring exposure to ionising radiation. Conclusion: There is no evidence to support the clinical effectiveness of routine investigation of children with confirmed UTI. Primary research on the effectiveness, in terms of improved patient outcome, of testing at all stages in the investigation of confirmed urinary tract infection is urgently required

How does study quality affect the results of a diagnostic meta-analysis?

Background: The use of systematic literature review to inform evidence based practice in diagnostics is rapidly expanding. Although the primary diagnostic literature is extensive, studies are often of low methodological quality or poorly reported. There has been no rigorously evaluated, evidence based tool to assess the methodological quality of diagnostic studies. The primary objective of this study was to determine the extent to which variations in the quality of primary studies impact the results of a diagnostic meta-analysis and whether this differs with diagnostic test type. A secondary objective was to contribute to the evaluation of QUADAS, an evidence-based tool for the assessment of quality in diagnostic accuracy studies. Methods: This study was conducted as part of large systematic review of tests used in the diagnosis and further investigation of urinary tract infection (UTI) in children. All studies included in this review were assessed using QUADAS, an evidence-based tool for the assessment of quality in systematic reviews of diagnostic accuracy studies. The impact of individual components of QUADAS on a summary measure of diagnostic accuracy was investigated using regression analysis. The review divided the diagnosis and further investigation of UTI into the following three clinical stages: diagnosis of UTI, localisation of infection, and further investigation of the UTI. Each stage used different types of diagnostic test, which were considered to involve different quality concerns. Results: Many of the studies included in our review were poorly reported. The proportion of QUADAS items fulfilled was similar for studies in different sections of the review. However, as might be expected, the individual items fulfilled differed between the three clinical stages. Regression analysis found that different items showed a strong association with test performance for the different tests evaluated. These differences were observed both within and between the three clinical stages assessed by the review. The results of regression analyses were also affected by whether or not a weighting (by sample size) was applied. Our analysis was severely limited by the completeness of reporting and the differences between the index tests evaluated and the reference standards used to confirm diagnoses in the primary studies. Few tests were evaluated by sufficient studies to allow meaningful use of meta-analytic pooling and investigation of heterogeneity. This meant that further analysis to investigate heterogeneity could only be undertaken using a subset of studies, and that the findings are open to various interpretations. Conclusion: Further work is needed to investigate the influence of methodological quality on the results of diagnostic meta-analyses. Large data sets of well-reported primary studies are needed to address this question. Without significant improvements in the completeness of reporting of primary studies, progress in this area will be limited