- Email: [email protected]
In vivo histopathology of lymphocytic colitis
At the Focal Point
Commentary Carcinoid tumor is the most common primary tumor of the small bowel; it arises from the enterochromaffin cells of Kulchitsky, neural crest cells situated at the base of the crypts named after Johann Nathanael Lieberku¨hn. Of note, in the mid 1700s, Lieberku¨hn invented a variety of microscopes, one based on Fahrenheit’s solar microscope and later termed a Lieberku¨hn, and another called ‘‘Wundergla¨ser,’’ which was used to explore the vasculature and to detail the intricacies of fluid motion within living creatures. Today, enterochromaffin cells are believed to be part of the amine precursor uptake and decarboxylation system and to serve an endocrine function. Most of these NETs are clinically silent, but they may cause abdominal pain, intestinal obstruction, weight loss, a palpable mass, bowel perforation, or even bleeding. Carcinoid tumors typically appear as firm, yellow, submucosal nodules, and, because they may grow through the muscularis mucosa and the bowel wall into the mesentery, EUS is important before their endoscopic removal. Duodenal carcinoid is rare, accounting for only 2% of such lesions in the small intestine; they are seen with decreasing frequency from the first to the third part of the duodenum and typically are slow growing. An association of small-bowel carcinoids has been described with the Zollinger-Ellison syndrome and with multiple endocrine neoplasia, type I. Somatostatin receptor scintigraphy is useful to localize and follow NETs, because the concentration of receptor sites is high in GI carcinoids. Lawrence J. Brandt, MD Associate Editor for Focal Points
In vivo histopathology of lymphocytic colitis
A 75-year-old man with an 8-month history of diarrhea had a colonoscopy as part of his evaluation. The colonic mucosa appeared normal by white light endoscopy (A). A new, portable confocal miniprobe, the Z-probe (Mauna Kea Technologies, Paris, France), was introduced into the colon via the instrument channel of an endoscope (13910PKS, Karl Storz, Germany). Real-time fluorescence microscopy was performed after the administration of 5 mL of 1% fluorescein, after which single video frames were reconstructed by a special computer algorithm (‘‘mosaicing’’). Panel A shows such an image of the patient’s rectum (B). Panels B and C correspond to larger
fields of view (B). The crypts are slightly distorted but not destroyed, and the unusual distance between crypts is accounted for by increased mononuclear inflammation in the lamina propria. In contrast, C shows a laser-microscopic image of the normal rectum, in which the pits stand close to each other and the cryptal architecture is not distorted. In the absence of inflammatory changes during white light endoscopy, and in accordance with the patient’s symptoms, these findings were highly suggestive for lymphocytic colitis. After confocal laser-microscopy, a biopsy specimen was taken for standard histopathology and confirmed the
398 GASTROINTESTINAL ENDOSCOPY Volume 66, No. 2 : 2007
www.giejournal.org
At the Focal Point
presumptive diagnosis (D, H&E, orig. mag. 100). The patient was treated with oral budesonide, and his symptoms improved rapidly. Miniprobe-based confocal microscopy has the potential to detect microscopic colitis in vivo, therefore reducing the number of biopsy specimens necessary to establish such a diagnosis.
DISCLOSURE
www.giejournal.org
Volume 66, No. 2 : 2007 GASTROINTESTINAL ENDOSCOPY 399
The Confocal Miniprobe and Cellvizio-GI were supplied by Mauna Kea Technologies (Paris, France) for research purposes, without further costs. The authors have no other disclosures.
At the Focal Point
Alexander Meining, MD, Susanne Schwendy, MD, Valentin Becker, MD, Roland M. Schmid, MD, Christian Prinz, MD, II Medical Department, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
doi:10.1016/j.gie.2006.12.027
Commentary This presentation nicely illustrates another step in technologic advancement. A colon that appears normal under white light is judged abnormal with miniprobe confocal fluorescein microscopy. Whether the pattern of crypt separation shown here and accounted for by mononuclear cell infiltration is pathognomonic for lymphocytic colitis, highly characteristic, or nonspecific requires further investigation. The stated advantage of confocal microscopy, however, is not necessarily to diminish the number of biopsy specimens that need be taken, but rather to enable highly targeted biopsy specimens to be diagnosticdor perhaps to allow diagnosis by observation or ‘‘optical biopsy’’ alone. When Ovid wrote, ‘‘The cause is hidden, the effect is obvious to all,’’ he was not describing lymphocytic colitis, but confocal microscopy may, like biopsy, reveal hidden causes. Lawrence J. Brandt, MD Associate Editor for Focal Points
An incarcerated prosthetic tooth in the vermiform appendix
A 77-year-old woman with a history of hypertension and diabetes mellitus presented with lower abdominal pain. Abdominal CT revealed a metallic foreign body within the right pelvic area (A). Although the patient denied ingestion of any object, she had noticed the loss of a prosthetic tooth. Colonoscopy revealed an edematous appendix orifice (B), but the foreign body was hidden within the vermiform appendix. The patient was given the choice of treatment by either endoscopy or appendectomy; the risks related to each procedure were explained.
Although she understood the risks associated with endoscopy, eg, perforation, she chose endoscopic treatment. The procedure was performed after making preparations for emergency surgery in the event of complications. The foreign body was grasped and held under fluoroscopy by using grasping forceps (C). It was removed from the vermiform appendix and subsequently from the colon without any complications. The foreign body, 13-mm long and 8 mm in diameter, was a prosthetic crown and post (D). Thereafter, symptoms promptly improved, and the
400 GASTROINTESTINAL ENDOSCOPY Volume 66, No. 2 : 2007
www.giejournal.org
Commentary Carcinoid tumor is the most common primary tumor of the small bowel; it arises from the enterochromaffin cells of Kulchitsky, neural crest cells situated at the base of the crypts named after Johann Nathanael Lieberku¨hn. Of note, in the mid 1700s, Lieberku¨hn invented a variety of microscopes, one based on Fahrenheit’s solar microscope and later termed a Lieberku¨hn, and another called ‘‘Wundergla¨ser,’’ which was used to explore the vasculature and to detail the intricacies of fluid motion within living creatures. Today, enterochromaffin cells are believed to be part of the amine precursor uptake and decarboxylation system and to serve an endocrine function. Most of these NETs are clinically silent, but they may cause abdominal pain, intestinal obstruction, weight loss, a palpable mass, bowel perforation, or even bleeding. Carcinoid tumors typically appear as firm, yellow, submucosal nodules, and, because they may grow through the muscularis mucosa and the bowel wall into the mesentery, EUS is important before their endoscopic removal. Duodenal carcinoid is rare, accounting for only 2% of such lesions in the small intestine; they are seen with decreasing frequency from the first to the third part of the duodenum and typically are slow growing. An association of small-bowel carcinoids has been described with the Zollinger-Ellison syndrome and with multiple endocrine neoplasia, type I. Somatostatin receptor scintigraphy is useful to localize and follow NETs, because the concentration of receptor sites is high in GI carcinoids. Lawrence J. Brandt, MD Associate Editor for Focal Points
In vivo histopathology of lymphocytic colitis
A 75-year-old man with an 8-month history of diarrhea had a colonoscopy as part of his evaluation. The colonic mucosa appeared normal by white light endoscopy (A). A new, portable confocal miniprobe, the Z-probe (Mauna Kea Technologies, Paris, France), was introduced into the colon via the instrument channel of an endoscope (13910PKS, Karl Storz, Germany). Real-time fluorescence microscopy was performed after the administration of 5 mL of 1% fluorescein, after which single video frames were reconstructed by a special computer algorithm (‘‘mosaicing’’). Panel A shows such an image of the patient’s rectum (B). Panels B and C correspond to larger
fields of view (B). The crypts are slightly distorted but not destroyed, and the unusual distance between crypts is accounted for by increased mononuclear inflammation in the lamina propria. In contrast, C shows a laser-microscopic image of the normal rectum, in which the pits stand close to each other and the cryptal architecture is not distorted. In the absence of inflammatory changes during white light endoscopy, and in accordance with the patient’s symptoms, these findings were highly suggestive for lymphocytic colitis. After confocal laser-microscopy, a biopsy specimen was taken for standard histopathology and confirmed the
398 GASTROINTESTINAL ENDOSCOPY Volume 66, No. 2 : 2007
www.giejournal.org
At the Focal Point
presumptive diagnosis (D, H&E, orig. mag. 100). The patient was treated with oral budesonide, and his symptoms improved rapidly. Miniprobe-based confocal microscopy has the potential to detect microscopic colitis in vivo, therefore reducing the number of biopsy specimens necessary to establish such a diagnosis.
DISCLOSURE
www.giejournal.org
Volume 66, No. 2 : 2007 GASTROINTESTINAL ENDOSCOPY 399
The Confocal Miniprobe and Cellvizio-GI were supplied by Mauna Kea Technologies (Paris, France) for research purposes, without further costs. The authors have no other disclosures.
At the Focal Point
Alexander Meining, MD, Susanne Schwendy, MD, Valentin Becker, MD, Roland M. Schmid, MD, Christian Prinz, MD, II Medical Department, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
doi:10.1016/j.gie.2006.12.027
Commentary This presentation nicely illustrates another step in technologic advancement. A colon that appears normal under white light is judged abnormal with miniprobe confocal fluorescein microscopy. Whether the pattern of crypt separation shown here and accounted for by mononuclear cell infiltration is pathognomonic for lymphocytic colitis, highly characteristic, or nonspecific requires further investigation. The stated advantage of confocal microscopy, however, is not necessarily to diminish the number of biopsy specimens that need be taken, but rather to enable highly targeted biopsy specimens to be diagnosticdor perhaps to allow diagnosis by observation or ‘‘optical biopsy’’ alone. When Ovid wrote, ‘‘The cause is hidden, the effect is obvious to all,’’ he was not describing lymphocytic colitis, but confocal microscopy may, like biopsy, reveal hidden causes. Lawrence J. Brandt, MD Associate Editor for Focal Points
An incarcerated prosthetic tooth in the vermiform appendix
A 77-year-old woman with a history of hypertension and diabetes mellitus presented with lower abdominal pain. Abdominal CT revealed a metallic foreign body within the right pelvic area (A). Although the patient denied ingestion of any object, she had noticed the loss of a prosthetic tooth. Colonoscopy revealed an edematous appendix orifice (B), but the foreign body was hidden within the vermiform appendix. The patient was given the choice of treatment by either endoscopy or appendectomy; the risks related to each procedure were explained.
Although she understood the risks associated with endoscopy, eg, perforation, she chose endoscopic treatment. The procedure was performed after making preparations for emergency surgery in the event of complications. The foreign body was grasped and held under fluoroscopy by using grasping forceps (C). It was removed from the vermiform appendix and subsequently from the colon without any complications. The foreign body, 13-mm long and 8 mm in diameter, was a prosthetic crown and post (D). Thereafter, symptoms promptly improved, and the
400 GASTROINTESTINAL ENDOSCOPY Volume 66, No. 2 : 2007
www.giejournal.org