Diagnosis in bile acid-CoA: Amino acid N-acyltransferase deficiency

Figure 2 Photomicrographs of liver immunostained for enzymes that subserve bile-acid amidation. A: Main image: Core needle biopsy specimen, patient liver (age 57 d); inset, control livers (1, infant, matched for age with patient, with cholestasis and extrahepatic biliary atresia; 2, infant, matched for age with patient, with intrahepatic cholestasis in setting of absence of bile salt export pump (BSEP) expression; and 3, adult without cholestasis). The patient liver lacks immunohistochemically demonstrable bile acid-CoA: amino acid N-acyltransferase (BAAT). Granular cytoplasmic marking, suggestive of peroxisomal location, is found in (3); marking is more diffuse in the livers of age-matched infants; B: Tissue specimens as in (A). Diffuse cytoplasmic marking for cholate-CoA ligase (CCL) is seen in patient liver (main image) and in control livers (1, infant, matched for age with patient, with cholestasis and extrahepatic biliary atresia; 2, infant, matched for age with patient, with intrahepatic cholestasis in setting of absence of BSEP expression; and 3, adult without cholestasis). A, anti-BAAT antibody, and B, anti-CCL antibody (see principal text for sources); in all images, reaction development with EnVision proprietary technique (Dako UK, Ely, United Kingdom), haematoxylin counterstain, original magnification 200 ×.