Case Presentation: A 21-year-old male with end-stage renal disease for 3 years (cause unknown) presented to the hospital with a 19lb weight loss (10% of body weight) over 2 months. Exam was notable for jaundice, diffuse abdominal tenderness, and innumerable purple, papular lesions covering his body, which he had noticed for 8 months. Labs revealed an alkaline phosphatase of 969, bilirubin of 15.2 (12.6 direct), AST/ALT of 28/52, and an INR of 1.8. Total cholesterol was 448 (HDL <10) and triglyceride was 346. MRCP showed multifocal areas of narrowing in the common bile and intrahepatic ducts with segmental areas of intrahepatic biliary ductal dilatation, classic for primary sclerosing cholangitis (PSC). However, liver biopsy was consistent with primary biliary cholangitis. A colonoscopy performed to evaluate for PSC-associated ulcerative colitis found plaques appearing to be lipid-laden, supporting the diagnosis of PSC. Upon biopsy, colonic and skin lesions revealed no lipid deposition, casting doubt on the diagnosis of PSC. Instead, both showed significant growth of histiocytes that were CD68+, CD1a-, and S100-, consistent with Xanthoma Disseminatum (XD). Re-examination of the liver biopsy found the same histiocyte infiltration, confirming the diagnosis of disseminated XD.
Discussion: Liver failure is a common problem encountered by the hospitalist. While laboratory testing and imaging often yields a diagnosis, liver biopsy is sometimes required. Although liver biopsy is considered the gold standard, it is not infallible with one study finding interobserver agreement as low as 50%. As such, a diagnosis based on liver biopsy should be reconsidered if inconsistent with the clinical picture.Xanthoma disseminatum is a very rare, primarily dermatologic process of non-Langerhans cell histiocytosis. Since first diagnosed in 1938, only ~100 case reports have been published. XD is more common in men, with diagnosis typically in the 3rd decade of life. A proliferation of histiocytes, it’s characterized by cutaneous lesions, described as reddish-brown or yellow-colored papules on the skin often involving the trunk, face, and skin flexures. While XD is typically benign, with spontaneous remission possible, a handful of case reports have described systemic involvement, which carries a very poor prognosis. Immunohistochemical staining is necessary for distinguishing XD from other histiocytosis-proliferating diseases, and will show CD1a and S100 negativity, and CD68 positivity, as in this case. Treatment for XD is based on case reports, and can involve steroids, immunosuppressive regimens, and chemotherapy. Based on an extensive literature search, to the best of our knowledge this is the first case of XD causing liver failure in an adult.
Conclusions: The case demonstrates how liver biopsy must be evaluated in the content of the clinical picture. When evidence supporting the biopsy result is contradictory, re-examination of the origin tissue can lead to a diagnosis.