Hepatic fibrin-ring granulomas in giant cell arteritis

Granulomatous liver diseases

A granuloma is a discrete collection of activated macrophages and other inflammatory cells. Hepatic granulomas can be a manifestation of localized liver disease or be a part of a systemic process, usually infectious or autoimmune. A liver biopsy is required for the detection and evaluation of granulomatous liver diseases. The prevalence of granulomas on liver biopsy varies from 1% to 15%. They may be an incidental finding in an asymptomatic individual, or they may represent granulomatous hepatitis with potential to progress to liver failure, or in chronic disease, to cirrhosis. This review focuses on pathogenesis, histological features of granulomatous liver diseases, and most common etiologies, knowledge that is essential for timely diagnosis and intervention.

Fibrin Ring Granulomas in Checkpoint Inhibitor-induced Hepatitis

Fibrin ring granulomas are an uncommon finding in liver biopsies although they have been described in liver injury secondary to several infectious and noninfectious entities, most notably Q fever. Immune checkpoint inhibitors are recent advances in cancer therapy, and stimulate the immune system to cause antitumoral effects but may also lead to adverse immune events such as hepatitis and colitis. We report 2 patients on combination ipilimumab/nivolumab who developed hepatitis and had fibrin ring granulomas in their liver biopsies.

A Case of Acute Q Fever Hepatitis Diagnosed by F-18 FDG PET/CT

A 53-year-old man with fever of unknown origin underwent F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) as a workup for a fever of unknown origin. On presentation, he complained of fever, chills, and myalgia. The F-18 FDG PET/CT scan showed diffusely increased uptake of the liver with mild hepatomegaly. A liver biopsy then revealed fibrin-ring granulomas typically seen in Q fever. The patient was later serologically diagnosed as having acute Q fever as the titers for C. burnetii IgM and IgG were 64:1 and 16:1, respectively. He recovered completely following administration of doxycycline. This indicates that F-18 FDG PET/CT may be helpful for identifying hepatic involvement in Q fever as a cause of fever of unknown origin.

[Hepatic granulomas]

Liver granulomas are histopathologically defined and associated with various liver and non-livers disorders. There are five main causes of liver granulomatosis: primary biliary cirrhosis, tuberculosis, sarcoidosis, B and C viral hepatitis, and drug related. In the other cases, not associated with an underlying systemic granulomatous disease, a systematic diagnostic approach should be used to identify less common etiologies. After a careful diagnostic work-up, a long-term follow-up of patients with undetermined liver granulomatosis is mandatory as it may be a presenting feature of liver lymphoma.

A case of acute q Fever with severe acute cholestatic hepatitis

Minimal hepatic dysfunction can be common in acute Q fever, but severe acute cholestatic hepatitis is rarely reported. We report on a 55-year-old male with acute Q fever and severe acute cholestatic hepatitis. He complained of fever, jaundice, ascites, and restlessness on admission. A liver biopsy revealed the presence of compact fibrin-ring granulomas. Serologic titers for C. burnetii IgM and IgG were 2048:1 and 1024:1, respectively. C. burnetii DNA was detected by a nested polymerase chain reaction on the liver tissue.

Granulomas in the liver

Granulomatous diseases of the liver span a huge range of infectious, drug-related, and immunologic disorders. Familiarity with the different types of granulomas as well as how they present in different diseases can be helpful in narrowing the pathologic differential diagnosis. This review surveys both common and unusual granulomatous diseases with emphasis on practical diagnosis.

Hepatic fibrin-ring granulomas in granulomatous hepatitis: report of four cases and review of the literature

BACKGROUND

The differential diagnosis of hepatic fibrin-ring granulomas includes infective agents (Coxiella burneti, CMV, EBV,....), hypersensitivity to medication (allopurinol) and malignancy.

METHODS

During a period of 6 months, four patients presented at our university hospital with a similar clinical picture of fever and abnormal liver tests, and fibrin-ring granulomas on liver biopsy. Clinical course, laboratory and imaging findings, and histopathological features were compared.

RESULTS

Clinical manifestations, and laboratory and imaging findings were similar. Histopathological assessment of the hepatic fibrin-ring granulomas appeared not to be helpful in identifying the causative agent. Other histopathological features (e.g. sinusoidal rows of lymphocytes, eosinophilic polymorphonuclear infiltrate) were suggestive for the causative agent, yet conclusive identification was obtained by either serology (Q fever, CMV, EBV), or by exclusion with concomitant stop of medication (allopurinol).

CONCLUSIONS

In the differential diagnosis of hepatic fibrin-ring granulomas, serologic titers remain the determining factor, since an infective agent is the most common cause. When hepatic fibrin-ring granulomas are present, other histopathological features may be helpful in making the differential diagnosis.

Hepatic granulomas and hepatic sarcoidosis

The causes of hepatic granulomas are numerous and their identification can be difficult. Sarcoidosis is a main cause of hepatic granulomas. The mechanisms that initiate the formation of sarcoid granulomas are unknown. This article discusses the pathology of hepatic sarcoidosis and hepatic granulomas.

Transient hepatic fibrin-ring granulomas in a patient with acute hepatitis A

A case of acute hepatitis A associated with fibrin-ring granulomas in the liver is presented. Because a relationship between acute hepatitis A infection and granuloma formation had not previously been established, liver specimens were examined from both the hepatitic and recovery phases. Numerous fibrin-ring granulomas were observed in the parenchyma during the hepatitic phase. The cellular components of the granulomas were largely macrophages and CD4-positive T-cells. Granulomas had disappeared completely by the recovery phase. These results suggest that fibrin-ring granulomas were caused by hepatitis A virus infection. This virus may activate macrophages and CD4-positive T-cells through an as-yet undetermined mechanism.