Validation of a grading system for complicated diverticulitis in the prediction of need for operative or percutaneous intervention.

INTRODUCTION: The current surgical management of acute complicated diverticulitis has seen a major paradigm shift from routine operative intervention to a more conservative approach. This has been made possible by the widespread availability of computed tomography (CT) to enable stratification of the disease severity of acute complicated diverticulitis. The aim of this study was to retrospectively validate a CT grading system for acute complicated diverticulitis in the prediction of the need for operative or percutaneous intervention. METHODS: Hospital and radiology records were reviewed to identify patients with acute complicated diverticulitis confirmed by CT. A consultant gastrointestinal radiologist, blinded to the clinical outcomes of patients, assigned a score according to the CT grading system. RESULTS: Three hundred and sixty-seven patients (34.6%) had CT performed for acute diverticulitis during the study period. Forty-four patients (12.0%) had acute complicated diverticulitis (abscess and/or free intraperitoneal air) confirmed on CT. There were 22 women (50%) and the overall median age was 59 years (range: 19-92 years). According to the CT findings, there was one case with grade 1, eighteen patients with grade 2, four with grade 3 and twenty-one with grade 4 diverticulitis. Three patients with grade 2, three patients with grade 3 and ten patients with grade 4 disease underwent acute radiological or surgical intervention. CONCLUSIONS: The use of a CT grading system for acute complicated diverticulitis did not predict the need for acute radiological or operative intervention in this small study. Decision making guided by the patient's clinical condition still retains a primary role in the management of acute complicated diverticulitis.

Pitfalls in neuroimaging of headache: a case report and review of the literature.

Headache is a common symptom, with a lifetime prevalence of over 90% of the general population in the United Kingdom (UK). It accounts for 4.4% of consultations in primary care and 30% of neurology outpatient consultations. Neuroimaging is indicated in patients with red flag features for secondary headaches. The guidelines recommend CT or MRI scan to identify any intracranial pathology. We present a unique case where the initial noncontrast CT scan failed to identify a potential treatable cause for headache. A middle aged man presented with headache and underwent a CT scan without contrast enhancement. The scan was reported as normal. The headache persisted for years and the patient underwent a staging CT scan to investigate an oropharyngeal cancer. This repeat CT scan utilized contrast enhancement and revealed a meningioma. Along with other symptoms, headache is an established presenting complaint in patients with meningioma. The contrast enhanced CT brain proved superior to a nonenhanced CT scan in identifying the meningioma. In a patient with persistent headache where other causes are excluded and a scan is to be requested, perhaps contrast enhanced CT is a better option than a plain CT scan of brain.

MR colonography without bowel cleansing or water enema: a pilot study.

OBJECTIVES: The value of screening for colorectal cancer has been well demonstrated, and national programmes are being implemented. At present the primary imaging modality is colonoscopy, which has an associated morbidity and mortality. CT colonography (CTC) has been proposed as an alternative, but this is associated with radiation exposure and generally requires bowel preparation. The aim of this pilot study was to assess the feasibility of MR colonography (MRC) without bowel preparation or water enema for the detection of colorectal neoplasia. METHODS: Patients scheduled for colonoscopy were invited to participate in the study; informed consent was obtained. MRC (with oral barium faecal tagging and colonic air distension) was performed 1-2 weeks before the colonoscopy. Axial T(2) weighted single-shot fast spin-echo (prone and supine) and axial T(1) weighted fast spoiled gradient-recalled (pre- and post-iv gadolinium) supine MRI sequences were performed. The examinations were reported by two gastrointestinal radiologists by consensus. Colonoscopy following standard bowel preparation was performed by a single endoscopist blinded to the MRC results. Significant lesions were defined as polyps or masses >10 mm in diameter. RESULTS: 29 patients were studied. Colonoscopy revealed 25 mass lesions in 13 patients. MRC correctly identified four of the nine lesions >10 mm in diameter (sensitivity 44%; specificity 100%). Although specificity remained high for smaller lesions, sensitivity was poor. CONCLUSION: This pilot study has demonstrated the feasibility of performing MRC without bowel preparation or water enema. This would seem to be a promising modality for colorectal cancer screening. Larger studies are required to determine the accuracy of this modality for the detection of colorectal neoplasia.

Bile duct brushings cytology--improving sensitivity of diagnosis using the ThinPrep technique: a review of 113 cases.

OBJECTIVE: Common bile duct (CBD) brushings have been recognized as a technique of moderate sensitivity and high specificity in identifying carcinoma of the ampulla and pancreatico-biliary regions. This study evaluated the increase in sensitivity of this technique using the ThinPrep technique of specimen preparation when compared with conventional cytology smears. METHODS: A total of 113 bile duct brushings were included in the study (38 conventional smears and 75 slides prepared using the ThinPrep technique). All slides were reviewed by one cytologist. Five categories of reporting were used: inadequate, negative, atypia, suspicious and malignant. RESULTS: The inadequate category of reporting disappeared in the ThinPrep group with improved specimen fixation and preparation and hence reduced artefact. Sensitivity of diagnosis of malignancy increased from 39% in conventional smears to 53% in the ThinPrep group. Specificity, positive and negative predictive values and accuracy were 100%, 100%, 60% and 68% for conventional smears and were 100%, 100%, 60% and 72%, respectively, for ThinPrep specimens. CONCLUSIONS: ThinPrep technique was associated with increased sensitivity of diagnosis, in part due to improved specimen fixation and reduced artefact. Cytology of bile duct brushings is an important diagnostic tool for sites from which it can be difficult to obtain a histology biopsy. It may therefore provide the only opportunity for tissue diagnosis of carcinoma from these sites, hence the importance of optimizing sensitivity.

Long-term clinico-radiological assessment of endoscopic stapling of pharyngeal pouch: a series of cases.

The endoscopic division of the pharyngeal pouch wall with a mechanical stapling device has become increasingly popular. When compared to open excision, the reduced operative time, early resumption of oral intake, and short in-patient stay with no early recurrence of symptoms, are the proposed advantages. Small pouches or thick walled pouches are not suitable for stapling. From December 1996 to December 1999, 32 patients were admitted to the Aberdeen Royal Infirmary for endoscopic stapling of a pharyngeal pouch. Five patients were unsuitable for stapling. In addition, three patients were treated for pouch recurrence after an external approach. Two patients required repeat stapling at a later date. Our results are encouraging in terms of short operation time and hospital admission, improvement of symptoms and minimal complication rate. Fifteen patients were assessed 24 months after the procedure with satisfaction surveys and contrast swallow X-rays. Subjective improvement was sustained throughout this period, despite radiological evidence of persistence of the pharyngeal pouch.

Evaluation of 18F-FDG positron emission tomography in gastric and oesophageal carcinoma.

The aim of this study was to evaluate 18F-fluoro-deoxyglucose (FDG) positron emission tomography (PET) in gastric and oesophageal carcinoma. 16 patients with biopsy proven oesophageal or gastric carcinoma had PET scans. Four patients had advanced disease and received palliative treatment. The remaining 12 patients were randomized to immediate surgery or neoadjuvant chemotherapy. Three patients had repeat PET scans following chemotherapy. PET detected the primary tumour in all cases including stage T1 lesions. Involved locoregional nodes (N1, N2) were not identified separately from the primary tumour. Semiquantitative analysis was performed in the form of tumour to liver activity ratios (TLR). In general, the TLR values were higher in the higher T stages, although there was only one case each of T1 and T2 lesions. PET scanning using 18F-FDG is a sensitive method for detecting primary oesophageal and gastric cancers but is limited in locoregional staging.

Detection of response to chemotherapy using positron emission tomography in patients with oesophageal and gastric cancer.

BACKGROUND: The aim of the study was to determine whether 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) could detect response to chemotherapy in patients with oesophageal and gastric cancer. METHODS: Fourteen patients underwent imaging before and after chemotherapy using FDG-PET. Computed tomography (CT), dysphagia scores and weight changes were used for comparison of evidence of response. Tumour to liver ratios (TLRs) and influx constants for FDG (K) were used for quantification purposes. RESULTS: Thirteen of 14 lesions were successfully imaged before therapy. Changes were seen in all follow-up scans, ranging from a complete response to a 15 per cent increase in tumour FDG uptake. Response was demonstrated by CT in four patients; all four had large reductions in FDG uptake after chemotherapy. Two patients with an increase in FDG uptake reported no improvement in dysphagia and continued to lose weight during therapy. CONCLUSION: Changes in tumour FDG uptake were seen in all tumours after chemotherapy. FDG-PET may have a role to play in the assessment of patients with upper gastrointestinal malignancy receiving chemotherapy.

Down-regulation of poison ivy/oak-induced contact sensitivity by treatment with a class II MHC binding peptide:hapten conjugate.

Immune regulation of contact sensitivity to the poison ivy/oak catechol was studied at the level of class II MHC-restricted T cell recognition of hapten:peptide conjugates. In this study we have shown that 1) T cells from C3H/HeN (H-2k) mice, immunized with a synthetic I-Ak binding peptide coupled to 3-pentadecyl-catechol (PDC; a representative catechol in urushiol), recognized peptides derived from syngeneic cells linked to the same catechol; 2) T cells from draining lymph nodes of C3H/HeN mice skin-painted with PDC proliferated in response to a peptide carrier:PDC conjugate only when it was linked at the 7th, but not the 4th or the 10th, position on the peptide carrier; and 3) tolerization studies confirmed down-regulation of PDC-induced delayed-type hypersensitivity following treatment with a single I-Ak binding peptide carrying PDC covalently bound to a lysine residue at the middle (7th) TCR contact position. Tolerization with peptide:PDC conjugate resulted in abrogation of hapten-specific T cell proliferative responses that correlated with diminished IL-2 secretion. On the basis of these data we propose that it may be sufficient to couple the hapten at a single, well-chosen position on a carrier peptide to target a relevant population of T cells involved in contact sensitivity.

Isolation of nonobese diabetic mouse T-cells that recognize novel autoantigens involved in the early events of diabetes.

Insulin-dependent diabetes mellitus (IDDM) is thought to result from chronic, cell-mediated, autoimmune islet damage. Our aim was to identify the earliest T-cell autoantigen in IDDM, reasoning that this antigen could be causally involved in the initiation of the disease. Identification of the earliest beta-cell-specific autoantigen is extremely important in allowing advances in prevention and treatment of initial events in the development of inflammatory insulitis that precedes beta-cell destruction and overt diabetes. Therefore, we analyzed the proliferative responses of peripheral T-cells from young, female nonobese diabetic (NOD) mice to extracts of pancreatic beta-cell lines. We were able to demonstrate that T-cells responsive to beta-cell antigens exist in the peripheral lymphoid tissue of these mice in the absence of deliberate priming before the manifestation of histologically detectable insulitis. T-cell lines and clones isolated from the peripheral lymphatic tissues of young, unimmunized, female NOD mice were also shown to react with extracts of beta-cells. Fractionation of the beta-cell extracts showed that these T-cell clones recognized multiple beta-cell-specific autoantigens but none of the previously reported putative autoantigens (glutamic acid decarboxylase [GAD]65, GAD67, Hsp65, insulin, ICA 69, carboxypeptidase-H, and peripherin). Thus, we can conclude that these responses are specific for novel beta-cell autoantigens. Finally, NOD T-cell proliferative responses were also seen to an extract of human islets suggesting potential shared antigenic determinants between human and mouse beta-cells.(ABSTRACT TRUNCATED AT 250 WORDS)