An 84-year-old woman complained of o f dark brown urine. Her medical history was significant for hypertension, congestive heart failure, and supraventricular t achycardia. The arrhythmia had been treated t reated with amiodarone. She was also a lso on diuretics, nifedipine and aspirin. She had no history of alcohol abuse. Her bilirubin, alanine aminotransferase level and alkaline phosphatase levels were markedly elevated. Her serum levels of amiodarone was within the normal reference range. Prothrombin time and activated partial thromboplastin time were normal. Urinalysis was positive for bilirubin and urobilinogen. Viral hepatitis A, B, C markers and antimitochondrial and antinuclear antibodies were all negative. She was suspected to have obstruction of the biliary tree but endoscopic retrograde cholangiography revealed choleli cho lelithiasis, thiasis, and an ultrasound of the liver showed evidence of non-alcoholic steatosis. Her bilirubin increased further and it wa dec ided to perform a liver biopsy. The liver biopsy revealed portal fibrosis but no evidence of cirrhosis. The hepatocytes showed intense ballooning degeneration and abundant Mallory bodies. Hepatocytes from the liver biopsy core were then examined by an electron microscope. What most relevant finding would you expect in the cytoplasm of these hepatocytes?
a) Polar bodies b) Dohle's bodies c) Hematoxylin bodies d) Lamellar bodies e) Negri bodies The correct answer is D Explanation The answer should be Lamellar bodies The history and histology should have pointed you towards amiodarone-induced hepatotoxicity. You should then be aware that a characteristic feature of amiodarone-induced hepatotoxicity on electron microscopy is the finding of lamellar bodies. If you were unaware of this fact, you could also have come to the correct answer by elimination of the other choices.
The histomorphologic findings of the liver biopsy were co nsistent with amiodaro amiodaroneneinduced cholestatic hepatotoxicity. Therefore you should expect the electron microscopic examination to confirm this diagnosis.The single feature t hat is virtually diagnostic of amiodarone-induced hepatotoxicity on electron e lectron microscopic examination are cytoplasmic lysosomal lameller inclusions . Although we cannot completely exclude the possibility of liver damage secondary to medications other than amiodarone in this th is patient, the histologic findings and clinical
course are against this possibility. The patient was t aking multiple cardiac and hypertensive medications prior to and after the onset of her liver injury, including calcium channel blockers, diuretics, and aspirin. Calcium channel blockers as a class have been associated with hepatocellular and cholestatic injury, presumably through a hypersensitivity mechanism. However, in the reported cases with nifedipine-induced liver injury, only 1 of 10 cases had Mallory bodies present in the liver biopsy specimen. Lysosomal lamellar bodies occur almost uniformly in any pat ient taking amiodarone, even in the absence of overt liver damage, and therefore are not confirmatory of amiodarone toxicity. In our case, however, the histologic changes of cholestatic hepat itis with alcohol-like hepatocellular injury in the presence o f lysosomal lamellar inclusions is consistent with amiodarone toxicity as the major cau se of this patient¶s jaundice. Other causes of cholestasis, such as viral hepatitis, primary biliary cirrho sis, autoimmune hepatitis, and extrahepatic biliary obstruction, were ruled ou t by the serologic and imaging studies. The presence of bile duct s excluded the possibility of idiopathic adult ductopenia. There was also no history of alcohol abuse, which may cause a similar histologic picture. In the presence of cho lelithiasis, the possibility of transient gallstones in the common bile duct causing obstruction cannot be entirely excluded, but endoscopic retrograde cholangiography did not demonstrate obstruction, and the imaging studies (abdominal ultrasound and dimethyl iminodiacetic acid scan) performed at the peak of the jaundice were again negative. What
are the histological features of amiodarone-induced hepatotoxicity ? Histology is likely to show lobular architecture d istorted by moderate portal fibrosis and moderate pericellular sinusoidal fibrosis in zone 1 of the Rappapo rt acinus and focally irregular lobular sinusoidal fibrosis. No bridging fibrosis or cirrhosis is evident. The expanded portal tracts show moderate to severe ductular proliferation and a mild lymphocytic infiltrate with rare polymorphonuclear leukocytes. There is no cholangitis. The hepatocytes show intense ballooning degeneration and abundant Mallory bodies. Hepatocellular necrosis with neutrophil satellitosis are also present. Anisonucleosis, prominent binucleation, and glycogenated nuclei are present. Bile stasis has no zonal distribution and is canalicular and cytoplasmic often in areas of ballooned, degenerated liver Periodic acid±Schiff stain after diastase digestion shows abundant sinusoidal lining cells and macrophages with periodic acid±Schiff±positive ceroid-lipofuscin cytoplasmic pigment electron microscopic examination The diagnosis of amiodarone-induced hepatotoxicity is further supported by transmission electron microscopic examination, which revealed a variable number of cytoplasmic lysosomal lameller inclusions , compatible with secondary amiodarone-induced phospholipidosis. Such inclusions may be not ed in hepatocytes, bile duct ep ithelium, Kupffer cells, and macrophages. Additionally, the hepatocytes contain aggregates of paranuclear haphazardly arranged intermediate cytoplasmic filaments consistent with Mallory bodies. Small lipid droplets are noted in some hepatocytes. Abundant pericanalicular autophagic vacuoles and secondary lysosomes with a granular matrix
reflecting bile stasis were present. Few canaliculi show dilatation with conde nsed pericanalicular filaments, distorted, focally flattened microvilli, and electron-dense granular luminal contents presumed to be bile. Degenerated hepatocytes, portal fibrosis, and portal neutrophils and lymphocytes are also noted. History
Cholestasis has been reported as a rare presentation among patients with amiodarone hepatotoxicity. There are reports of patients who presented with jaundice as the major clinical manifestation of amiodarone hepatotoxicity. Cholestasis appears to o ccur in older patients . The presence of increased serum bilirubin level indicated a poor prognosis even with the relatively unremarkable serum alanine aminotransferase and aspartat e aminotransferase levels. Histopathologic findings of hepatic fibrosis and necrosis correlates highly with poor prognosis. Besides prognostic significance, histopatho logic examination of a liver biopsy specimen is of value in rendering the diagnosis of amiodarone-induced cholestatic liver injury. Steatosis, both macrovesicular and microvesicular, was the most frequent histopathologic change. Ba llooning of hepatocytes, Mallory bodies, and fibrosis were also common. Characteristic lamellar lysosomal inclusion bodies representing phospho lipidosis are usually found ultrastructurally. Lamellar bodies Lamellar bodies are ctoplasmic inclusion bodies that contain lipids to be secreted. In alveolar epithelial cells lamellar bodies are specialized for the storage of surfactant phospholipids. Secretion of lung surfactant occu rs via exocytosis of lamellar bodies in alveolar epithelial cells and is one of the most important aspects in lung surfactant homeostasis. Other types of intracytoplasmic bodies Döhle's bodies, Döhle's inclusion bodies, round to oval blue-staining inclusions seen in the periphery of the cytoplasm of neutrophils, consisting mainly of RNA derived from rough endoplasmic reticulum; they are found in association with many infections, burns, aplastic anemia, uncomplicated pregnancy, a nd after administration of toxic agents. Similar structures, usually larger and more prominent, are present in granulocytes o ther than neutrophils in the May-Hegglin anomaly. Called also Amato b's and leukocyte inclusions. body , a dense, homogeneous, cyanophilous particle consisting of the denatured nuclear material of an injured cell together with a small amount of cytoplasm, occurring in systemic lupus erythematosus; lymphocytes that ingest such particles are known as LE cells. Called also LE b. Hematoxylin
Negri bodies, oval or round inclusion bodies, seen in the cytoplasm and sometimes in the processes of nerve cells of rabid animals or patients with rabies after death; their presence is considered conclusive proof of rabies. Polar bodies, 1. the small nonfunctional cells with a haploid chromosome complement,
consisting of a small amount of cytoplasm and a nucleus, resulting from unequal division of the primary oocyte (first polar b.) and, if fertilization occurs, of the secondary oocyte (second polar b.); the polar body appears as a speck at the animal pole of the egg. 2. metachromatic granules located at one or both ends of a bacterial cell.
