Roger Detry

MRI of complicated anal fistulae: comparison with digital examination.

Objectives The assessment of complicated anal fistulae is based on digital examination. Our objective was to study the potential role of MRI in this setting by comparing preoperative digital examination with MRI. Materials and Methods Digital examination and MRI were prospectively and blindly interpreted in 13 patients with complicated anal fistulae. Surgical findings were used as standard. Results Complete agreement between the results of digital examination and the surgical findings was observed in 8 patients and between the results of MRI and the surgical findings in 12 patients. Digital examination misclassified two low transsphincteric fistulae as high transsphincteric and missed high secondary extensions or abscesses in three other patients. Magnetic resonance misclassified only one suprasphincteric fistula as low transsphincteric and did not overlook high secondary extensions or abscesses. Conclusion These findings suggest that MRI may show abnormalities not detected by preoperative digital examination.

Familial adenomatous polyposis associated with multiple adrenal adenomas in a patient with a rare 3' APC mutation.

Familial adenomatous polyposis (FAP) is characterised by hundreds of colorectal adenomas. Endocrine neoplasms have occasionally been reported, as have gastric polyps, which are usually hamartomatous in the fundus of the stomach and adenomatous in the antrum. A 57 year old man with colorectal, gastric, and periampullary adenomatous polyposis, in association with three bilateral adrenocortical adenomas, is presented. Mutation screening showed a 5960delA germline mutation in the adenomatous polyposis coli (APC) gene predicted to lead to a premature stop codon. This mutation was found in three of the four children of the patient. Western blot analysis of a lymphoblastoid cell line derived from the patient failed to detect any truncated APC polypeptide. This rare 3′ mutation is responsible for an unusually complex and late onset phenotype of FAP.

Endocannabinoids regulate adipokine production and the immune balance of omental adipose tissue in human obesity.

Objectives:(1) To investigate whether modulation of the cannabinoid type 1 receptor (CB1R) directly regulates the production of adiponectin (ApN) and other adipokines in omental adipose tissue (OAT) of obese subjects, (2) to establish in which cellular fraction of OAT the effects of CB1R blockade take place and (3) to unravel the underlying mechanisms.Subjects and methods:OAT was obtained from 30 obese subjects (body mass index: 40.6±1.3 kg m−2) undergoing abdominal surgery. Primary cultures of explants or of freshly isolated adipocytes or stromal-vascular cells (SVCs) were used.Results:In OAT explants, the CB1R blocker Rimonabant upregulated ApN gene expression. mRNA abundance of omentin that exhibits insulin-sensitizing properties was upregulated as well. Conversely, mRNA levels of two pro-inflammatory cytokines, macrophage inflammatory protein (MIP)-1β and interleukin (IL)-7 were downregulated. We next examined where these effects took place within OAT. CB1R expression was similar in both cellular fractions. In isolated mature adipocytes, blockade of CB1R reproduced the increase of ApN mRNA and the decrease of IL-7 mRNA, while inducing a rise of ApN secretion into the medium. In isolated SVC, gene expression of omentin, which is restricted to this fraction, was augmented, while that of MIP-1β was diminished. Finally, we deciphered the mechanisms leading to ApN regulation by the endocannabinoid system (ES). We first established that ApN regulation was actually mediated by the CB1R: ApN gene expression was upregulated by Rimonabant and downregulated by the CB1R agonist arachidonyl-2-chloroethylamide (ACEA). Upregulation of ApN by Rimonabant was unaltered by inhibiting cAMP production. However, downregulation of ApN by ACEA was fully reversed by an inhibitor of p38 mitogen-activated protein kinase (p38MAPK) and ACEA increased p38MAPK phosphorylation.Conclusions:Blockade of CB1R attenuates the inflammatory state in both cellular fractions of OAT either by increasing ApN and omentin production or by decreasing mRNAs of MIP-1β and IL-7. ApN regulation by the ES partly involves p38MAPK.

MRI of the anal canal: correlation with histologic examination.

The purpose of this study was to correlate the MRI features of the anal canal with histologic findings. T1- and T2-weighted MR images of nine anal canals were obtained after fixation in 10% formalin. In three specimens, imaging was repeated after removal of histologic layers with a dissecting microscope. Corresponding histologic slices were stained with hematoxylin-eosin, Masson trichrome, and periodic acid-Schiff. Four layers were visualized on T2-weighted images. An inner layer of high signal intensity and a second layer of low signal intensity corresponded to the mucosa as well as mucous secretions and to the submucosa. The high signal intensity layer vanished at the distal part of the anal canal in accordance with the lack of mucus-secreting epithelium below the level of the dentate line. A third layer of intermediate signal intensity corresponded to the internal sphincter. A fourth layer of low signal intensity corresponded to the longitudinal muscle and external sphincter. T2-weighted MRI is capable of showing the internal architecture of the wall of the anal canal. In particular, the internal sphincter can be differentiated from the external sphincter and longitudinal muscle.

Idiopathic non-familial rectal and colonic varices requiring sigmoidorectal resection and coloanal anastomosis

A 32-year-old male patient presenting with huge varices involving the sigmoid colon and the entire rectum down to the dentate line is described. There was no familial history of gastrointestinal bleeding. No particular aetiology was identified. Marked anaemia due to recurrent bleeding required resection of the sigmoid colon and rectum. Restoration of the intestinal continuity was performed by a coloanal anastomosis. The patient did well and bleeding has not recurred. To our knowledge, no similar case of such varices requiring extensive rectal surgery to control bleeding has been described in the literature.

Mesenteric whirlpool sign detected at color doppler ultrasound: Diagnostic value in adults

The purpose of this study was to evaluate the diagnostic value of the “whirlpool sign” detected at color Doppler sonography in adults complaining of acute abdominal pain. During a 2-year period, the whirlpool sign was systematically looked for with color Doppler sonography in all patients admitted in the emergency room for acute abdominal pain. The whirlpool sign was observed in 13 patients: 2 cases of surgically proven primary volvulus of the small bowel, 10 cases of proven or suspected small bowel obstruction secondary to adhesions, and 1 case of acute leukemia with enlarged mesenteric lymph nodes. In the first 12 cases, the whirlpool sign was associated with radiologic (N=9) and sonographic (N=12) signs of small bowel obstruction. In the last case, no sign of obstruction was observed. In patients who had the whirlpool sign and who underwent operations (N=6), primary or secondary volvulus was present in 3 cases but was absent in the other 3 cases. The whirlpool configuration detected with color Doppler sonography has to be considered as a sign of limited value, because it may be observed in various conditions, including primary or secondary volvulus, postsurgical adhesions without volvulus, and acute abdominal diseases without obstruction.

In Vitro Hyperresponsiveness to Tumor Necrosis Factor-α Contributes to Adipokine Dysregulation in Omental Adipocytes of Obese Subjects

Results: Adipocytes of obese subjects mainly overexpressed adipokines, in comparison with those of lean ones, when cultured in SVC-conditioned media. This was abrogated by immunoneutralization of TNF, indicating that among the numerous factors secreted by SVCs, TNFis a crucial contributor to adipokine dysregulation. Accordingly, adipocytes of obese subjects overproduced adipokines in response to direct exposure of TNF. This hyperresponsiveness was mediated by TNFreceptor 1 and hyperactivation of the nuclear factorB (NFB) pathway. Correspondingly, NFB activity was increased in adipocytes of obese subjects and correlated with adipocyte size, adipokine expression, and in vivo insulin resistance. Eventually adipokine overexpression in adipocytes of obese subjects was prevented by NFB inhibitors.