Alkaline phosphatase sarcoidosis

Sarcoidosis may lead to hyperphosphatasemia. Maddrey et al. (M2), who studied 20 patients with hepatic involvement, found that in one third, serum alkaline phosphatase values were normal in another third. 

Total or partial hypopituitarism may result from disorders such as hemochromatosis (S72) or sarcoidosis (S26), which may raise serum alkaline phosphatase because of their effect on the liver. However, no correlation can be demonstrated in these conditions between serum alkaline... 

An increase of a pulmonary isoform of a tissue nonspecific alkaline phosphatase isoenzyme activity has been observed in the bronchoalveolar lavage fluid (separated from cells) of patients affected by idiopathic pulmonary fibrosis, sarcoidosis, chronic bronchitis, and silicosis (Capelli et al. 1997). 

The most common liver function test abnormality in hepatic sarcoidosis is an elevated serum alkaline phosphatase, which is present in more than 90% of patients with signs or symptoms of hepatic sarcoidosis (59,67,68) but is found in as few as 15% (32/217) of patients with histologic evidence of disease (62). Occasionally, this elevation may exceed 5 to 10 times the upper limits of normal... 

Fifty to 70% of patients with clinical evidence of hepatic sarcoidosis have elevations in serum transaminases that are usually less elevated than the serum alkaline phosphatase (63,67). Hypoalbuminemia, hyperbilimbinemia, and hepatic encephalopathy may rarely occur with chronic progressive disease... 

As mentioned previously, patients with hepatic sarcoidosis may develop a chronic cholestatic syndrome with jaundice, fever, malaise, anorexia, weight loss, pruritus, and a cholestatic pattern of abnormal Uver function tests (77-79). These symptoms are often severe and require treatment. Prednisone in doses of 30 to 60 mg/day may improve symptoms, lower serum alkaline phosphatase levels, and improve hepatomegaly (77,96). Ursodeoxycholic acid, which inhibits intestinal absorption and increases biliary secretion of cholic and chenodeoxycholic acids (97), is often effective for the cholestatic syndrome of hepatic sarcoidosis (98,99). A dose of 10 mg/kg/day has been recommended (98,99). 

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