ABSTRACT
Introduction. Intussusception is a rare clinical entity in adults (<1% of intestinal obstructions). Colonic intussusception is even rarer, particularly when caused by lipomas. Case Presentation. A 47-year-old woman presented to our emergency department complaining of abdominal pain with vomiting and diarrhoea. X-ray and CT showed bowel obstruction due to ileocolonic and colocolonic intussusception; a giant colonic lipoma (9 × 4 × 4 cm) was recognizable immediately distally to the splenic flexure of the colon. The patient underwent emergency laparotomy and right hemicolectomy. Assessment of the resected specimen confirmed the diagnosis of giant colonic polypoid lesion near to the ileocecal valve, causing a 12 cm long intussusception with moderate ischemic damage. Conclusion. Colonic obstruction due to intussusception caused by lipomas is a very rare condition that needs urgent treatment. CT is the radiologic modality of choice for diagnosis (sensitivity 80%, specificity near 100%); since the majority of colonic intussusceptions are caused by primary adenocarcinoma, if the etiology is uncertain, the lesion must be interpreted as malignant and extensive resection is recommended. At present, surgery is the treatment of choice and determines an excellent outcome.
ABSTRACT
The mas-related gene (Mrg) family is a large family of G-protein-coupled receptors which are variable in number depending on species. The so-called sensory-neuron-specific receptors (SNSRs) make up a subset of the Mrg family, and several of these have been implicated in nociceptive processes. To verify their specific localization in sensory ganglia, we have determined the expression patterns of two of them, rMrgA and rMrgC, in a panel of rat tissues. The quantitative PCR results in the rat tissue panel indicate that, while several non-neuronal tissues contain significant levels of mRNA for both receptors, these two receptors are most highly expressed in dorsal root ganglia and trigeminal ganglia. Given this, we have examined the effects of spinal nerve ligation (SNL) on the expression of these genes. Peripheral neuropathy induced by ligation of spinal nerves at L5 and L6 resulted in a pronounced mechanical allodynia. These behavioral changes in tactile sensitivity were accompanied by significant decreases (10- to 100-fold) in the mRNA expression of both rMrgA and rMrgC exclusively in the L5 and L6 dorsal root ganglia ipsilateral to the SNL. In situ hybridization studies demonstrated that this decrease did not result from neuronal loss but rather from a reduction in the hybridization signals for rMrgC over small-to-medium diameter L5 and L6 dorsal root ganglia neurons. While the functional implications of the altered regulation of rMrgA and rMrgC in neuropathic pain models remain unclear, the results suggest that therapeutics targeting these receptors may have limited utility.
