Volume 137, Issue 1, Pages 101-109 (July 2009) Frequency of Mitochondrial Defects in Patients With Chronic Intestinal Pseudo- Obstruction  Aurélien Amiot, Maya Tchikviladzé, Francisca Joly, Abdelhamid Slama, Dominique Cazals Hatem, Claude Jardel, Bernard Messing, Anne Lombès  Gastroenterology  Volume 137, Issue 1, Pages 101-109 (July 2009) DOI: 10.1053/j.gastro.2009.03.054 Copyright © 2009 AGA Institute Terms and Conditions

Figure 1 Brain MRI of Patient 10 with POLG mutations. T2 FLAIR sequences showing symmetrical hyperintense signals in the white matter of the cerebellum (A) and occipital lobes (B), associated with mild cerebral atrophy (C). Gastroenterology 2009 137, 101-109DOI: (10.1053/j.gastro.2009.03.054) Copyright © 2009 AGA Institute Terms and Conditions

Figure 2 Skeletal muscle histochemical appearance of patients with CIPO of mitochondrial origin. Both patients 8 and 10 had alterations of their POLG gene. Cytochrome c oxidase–deficient fibers were prominent in some biopsies (fibers marked with an asterisk in patient 8's muscle). They were sometimes less obvious, only visible by the discrepancy between very low or absent cytochrome c oxidase activity and normal or increased SDH activity (muscle fiber indicated with the arrow in the serial muscle sections of patient 10's muscle, upper panel). Mitochondrial proliferation was most often mild and shown by the increase SDH staining under the muscle fibers membrane (arrows in patient 8's muscle). It rarely gave a typical “ragged-red” appearance, which in SDH histochemical stains gave an increased black signal in the whole muscle fiber (muscle fiber indicated by the empty arrow in patient 10's muscle). COX, cytochrome c oxidase histochemical stain; SDH, succinate dehydrogenase histochemical stain; Pt8, patient 8; Pt10, patient 10. Gastroenterology 2009 137, 101-109DOI: (10.1053/j.gastro.2009.03.054) Copyright © 2009 AGA Institute Terms and Conditions

Figure 3 Intestinal histochemical appearance in a patient with CIPO owing to the mtDNA tRNAleu(UUR) m.3243A>G mutation in the mtDNA.. Patient 6's intestinal wall sample had >80% mtDNA tRNAleu(UUR) 3243A>G “MELAS” mutation. Low magnification (×2.5) shows that, in a control intestinal wall sample, both cytochrome c oxidase and SDH histochemical stains are darker in intestinal mucosa (thin arrow) than in the 2 muscle layers (empty and black arrows). The inner circular muscle layer appears slightly darker than the outer longitudinal layer, but, within each layer, the mitochondrial histochemical staining is homogenous as shown at higher magnification (×40, lower panel). In patient 6's intestinal wall, the 2 muscular layers (empty and black arrows) have intense mitochondrial proliferation, as shown by the increased SDH staining (upper panel), and defective cytochrome c oxidase activity as shown by the decreased cytochrome c oxidase staining (middle panel). The patchy appearance of the cytochrome c oxidase histochemical stain is better observed at higher magnification (×40, lower panel). COX, cytochrome c oxidase histochemical stain; SDH, succinate dehydrogenase histochemical stain. Gastroenterology 2009 137, 101-109DOI: (10.1053/j.gastro.2009.03.054) Copyright © 2009 AGA Institute Terms and Conditions