Related Experiment Video
Updated: Feb 3, 2026
07:10
Measurement of the Hepatic Venous Pressure Gradient and Transjugular Liver Biopsy
Published on: June 18, 2020
22.8K
Mycobacterium chimaera Hepatitis: A New Disease Entity.
Nafis Shafizadeh1, Gillian Hale2, Julu Bhatnagar2
1Department of Pathology.
The American Journal of Surgical Pathology
|October 23, 2018
Summary
Mycobacterium chimaera infection can cause severe liver disease in patients after heart surgery. This study describes characteristic liver injury patterns, aiding diagnosis and treatment of this rare but serious condition.
Area of Science:
- Infectious Diseases
- Hepatology
- Pathology
Background:
- Mycobacterium chimaera, identified in 2004, is associated with disseminated disease, particularly in immunocompromised individuals.
- A global outbreak of M. chimaera infection linked to contaminated heater-cooler units post-open-heart surgery emerged in 2015.
- Patients present with systemic symptoms months to years after surgery, with significant morbidity and mortality.
Observation:
- Elevated liver function tests, predominantly biliary, were noted in affected patients.
- The study reports on 7 cases of M. chimaera liver disease in the United States.
- A consistent dual pattern of liver injury was observed in biopsies: sinusoidal histiocyte collections and venous outflow obstruction.
Findings:
- The characteristic dual liver injury pattern includes ill-formed granulomas and architectural changes of venous outflow obstruction.
- Two cases exhibited pericellular fibrosis, and two showed nodular regenerative hyperplasia, consistent with sinusoidal/venous injury.
- The sinusoidal granuloma location is postulated to contribute to venous obstructive changes.
Implications:
- Recognizing this unique dual liver injury pattern is crucial for pathologists to suggest M. chimaera infection.
- Early diagnosis and intervention can potentially improve outcomes for patients with this severe infection.
- This research highlights the importance of identifying and managing M. chimaera outbreaks linked to medical devices.
Related Concept Videos
01:08Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment
280
Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
280
01:26Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow
244
Chronic liver disease significantly impacts drug metabolism due to alterations in hepatic blood flow and enzyme accessibility. This disruption affects the body's pharmacokinetics—the movement and processing of drugs within the system. Key enzymes crucial for metabolizing medications become less accessible, changing how drugs are processed and utilized. Furthermore, liver disease influences the synthesis of plasma proteins, such as albumin and globulins, which play critical roles in drug...
244
01:22Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test
199
In clinical practice, the direct measurement of hepatic blood flow to evaluate liver function presents significant challenges due to the intricate and specialized nature of the necessary techniques. Consequently, healthcare professionals often rely on empirical estimates derived from thorough patient examinations and liver function tests to gauge liver health. Among the tools at their disposal, the Child–Pugh and MELD scoring systems stand out for their ability to categorize and assess...
199
01:14Effect of Hepatic Disease on Pharmacokinetics: Active Drug, Metabolite and Fraction of Metabolized Drug
231
In pharmacotherapy, monitoring drug concentrations is paramount, especially for drugs whose therapeutic effects hinge on both the active compound and its metabolite. Hepatic impairment profoundly influences drug potency by altering liver function. If the drug is more potent than its metabolite, impaired liver function amplifies drug activity due to elevated drug concentration levels. Conversely, if the metabolite holds greater potency, diminished liver function diminishes drug activity by...
231
01:21Hepatic Portal System
5.9K
The hepatic portal system, a critical part of our circulatory framework, transports nutrient-laden, deoxygenated blood from the gastrointestinal tract and spleen to the liver. This ingenious system plays an indispensable role in maintaining our body's metabolic equilibrium.
At its core, the hepatic portal vein is the result of a confluence of the superior and inferior mesenteric veins along with the splenic vein. Each of these veins has a unique role. The superior mesenteric vein is...
At its core, the hepatic portal vein is the result of a confluence of the superior and inferior mesenteric veins along with the splenic vein. Each of these veins has a unique role. The superior mesenteric vein is...
5.9K
01:16Hepatic Drug Excretion: Influencing Factors
581
The biliary system of the liver, crucial for bile secretion and drug excretion, comprises intrahepatic bile ducts that merge to form the common hepatic duct. This duct, carrying hepatic bile, combines with the cystic duct, draining the gallbladder and forming the common bile duct, which empties into the duodenum. Bile, produced by hepatic cells lining the bile canaliculi, is composed primarily of water, bile salts, pigments, electrolytes, and lesser amounts of cholesterol and fatty acids. Bile...
581