Mayo Clinic Population-based Study Characterizes Hepatic Sarcoidosis
The work results from the fact that the clinical characteristics and outcome of hepatic sarcoidosis are still not well-defined, and most of the information available is from referral-based cohort studies, which may not fully reflect the disease as it occurs in the community.
The findings were reported in a study titled “Clinical Characteristics and Outcome of Hepatic Sarcoidosis: A Population-Based Study 1976–2013,” published in the American Journal of Gastroenterology.
Researchers analyzed 345 patients with hepatic sarcoidosis diagnosed from 1976 to 2013 in Olmsted County, Minnesota.
Only four patients complained of abdominal pain, and two patients had an enlarged liver during a physical examination. For the remaining patients, the diagnosis of hepatic sarcoidosis was only possible based upon biochemical tests (which are not commonly recommended) and additional imaging studies.
The team observed that the incidence of liver involvement was only 6% in their group (19 of 345 cases), and that patients were asymptomatic for liver disease.
These results reflect those of previous reports, ranging from 5% to 30%, although a different study reported that this incidence could be as high as 70%, according to data collected from autopsies. Therefore, researchers suggested that the reported discrepancies in incidence rates could be due to the asymptomatic nature of hepatic sarcoidosis.
The majority of patients in the analyzed group had increased levels of alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT), used as biomarkers of liver function, with no significant or severe changes reported for other liver enzymes, such as transaminases.
Imaging evaluation showed that six patients had nodular lesions with low density, and three patients had enlarged livers. The remaining patients had no physical alterations to their livers. Additional liver biopsies revealed non-caseating granulomas – a hallmark of sarcoidosis – in 88% of these patients.
The results suggest that “negative imaging study does not exclude hepatic sarcoidosis and liver biopsy should be performed if the clinical suspicion remains high,” the researchers wrote.
The team also reported that two patients presented cirrhosis (liver cell death) at baseline, and two other patients developed this severe condition during follow-up evaluations – one year and 12 years after diagnosis.
Therapy for management of hepatic sarcoidosis is commonly reserved for patients with severe liver conditions, and is based on glucocorticoids and other immunosuppressive medicines.
“Observation is usually recommended for patients with only mildly elevated liver enzymes,” researchers wrote.
This therapeutic strategy is based on the lack of clinical information demonstrating the effectiveness and long-term benefit of these drugs for the treatment of sarcoidosis with liver involvement.
“Involvement of the liver by sarcoidosis was seen in 6% of patients with sarcoidosis. The majority of patients were asymptomatic,” the team wrote in the study. “Elevated ALP and GGT were the most common abnormal biochemical tests. Liver biopsy revealed non-caseating granuloma in almost all cases.”
“Generalizability of the observations to other populations may be limited, as the studied population was predominantly Caucasian. The prevalence of liver disease may be higher in more diverse populations,” the researchers added.