Liver disease in rheumatoid arthritis and Sjøgren's syndrome. Prospective study using biochemical and serological markers of hepatic dysfunction

Critical evaluation of gamma-glutamyl transpeptidase levels in rheumatoid arthritis and laboratory indices of disease activity

Fifty patients with rheumatoid arthritis (RA) were studied to find a possible correlation between some humoral parameters, considered as indexes of the active inflammation, and serum gamma-glutamyl transpeptidase (GGTP); 31 patients with osteoarthrosis were examined as controls. The low coefficient of correlation, obtained in subjects with RA, between GGTP and CRP, alpha 1-acid glycoprotein, fibrinogen and ESR (p less than 0.05) seems to indicate that measurement of this enzyme is of little practical value as an index of the activity of RA. Furthermore, the resulting correlations between serum GGTP and other liver function tests in relation to anti-inflammatory and sedative therapy in patients with RA are considered.

Smooth-muscle antibodies in rheumatoid arthritis

Smooth-muscle antibodies (SMA) detected by the indirect immunofluorescence method were found more often in rheumatoid arthritis (RA) patients (15.3%) than in normal controls (7.6%) (0.02 > p > 0.01). The increased frequency was due to IgG-antibodies which occurred in 12.2% of RA patients, in 4.1% of normal controls and in 7.3% of patients with other arthritic diseases. Eight of 9 IgG-SMA-positive RA sera reacted with F-actin, and one serum contained non-actin antibodies. In RA, ANA were found in 35.7%, glomerular antibodies in 1.0%, parietal cell antibodies in 4.1% and mitochondrial antibodies in 2.0%. SMA were associated with the occurrence of rheumatoid factors and mitochondrial antibodies (0.02% > p and 2p = 0.04, respectively). In the SMA-positive group the erythrocyte sedimentation rate was higher and elevated serum alkaline phosphatase values were found more often than in the SMA-negative group.

Liver disease in rheumatoid arthritis

Patients with active rheumatoid arthritis frequently have hepatosplenomegaly and biochemical features of hepatic disease. A prospective study with liver biopsy has been carried out in a series of 31 rheumatoid arthritis patients with clinical and/or biochemical evidence of hepatic dysfunction. Four of the 31 (13%) were found to have definable chronic liver disease, normal hepatic histology or non-specific reactive changes being found in the remainder. In the large majority of patients the hepatic abnormality in rheumatoid arthritis remains functional and unexplained.

Liver function in some common rheumatic disorders

Liver function was studied primarily by determination of serum gamma glutamyl transferase and alkaline phosphatase. In subsamples of patients the investigation was extended by determination of serum amino-transferases, isoenzyme analysis of alkaline phosphatase, 99mtechnetium scintigraphy, and liver biopsy. In 183 in-patients with rheumatoid arthritis, the serum gamma glutamyl transferase level was elevated in 47% and serum alkaline phosphatase (of liver origin) in 24%. A concomitant increase in serum aminotransferases was found in 15% of patients with elevated gamma glutamyl transferase level. A closely similar pattern was found in 45 patients with non-rheumatoid arthritis (ankylosing spondylitis, psoriatic arthritis, reactive arthritis, and undefined arthritis), and in 5 patients with polymyalgia rheumatica. In 23 patients with non-rheumatic inflammation (pneumonia), liver dysfunction was common, though the pattern of serum enzyme changes was different. In rheumatoid arthritis, liver scanning showed irregular or low uptake, but biopsy only indicated reactive hepatitis. Hepatotoxicity could not be traced to any single drug or combination of drugs given. On the contrary, chloroquine appeared to reduce serum gamma glutamyl transferase, and corticosteroids had a similar effect on serum alkaline phosphatase. In patients not treated with corticosteroids, both serum gamma glutamyl transferase and alkaline phosphatase were weakly to moderately correlated with laboratory indices of disease activity (ESR and serum orosomucoid). The frequently occurring isolated increase of serum gamma glutamyl transferase and/or serum alkaline phosphatase in arthritis may be an unspecific reaction to inflammation.

Studies on the frequency and pathogenesis of liver involvement in rheumatoid arthritis

A systematic prospective survey of 100 outpatients with rheumatoid arthritis revealed that 45 had biochemical evidence of liver disease. In most cases this was due to increases in total serum alkaline phosphatase (ALP) and/or gammaglutamyl transpeptidase (GGT). Examination of serum ALP isoenzyme profiles in 50 of the patients showed that the liver isoenzyme was the sole or major component in 44 patients, including many with normal total ALP levels. 18% had raised serum liver ALP together with raised GGT, suggestive of an underlying hepatobiliary lesion. No correlation could be detected between raised serum levels of liver enzymes and the age or sex of the patient, duration or severity of arthritis, and drug or alcohol history. However, there was a significant correlation between raised serum ALP and lacrimal or salivary gland dysfunction. It is suggested that immunological mechanisms may be involved in the development of hepatic abnormalities in rheumatoid arthritis.

Hypercalcaemia in rheumatoid arthritis: investigation of its causes and implications

When correction was made for hypoalbuminaemia, 23 of 50 ambulant patients with definite or classical rheumatoid arthritis were found to have hypercalcaemia. When these 23 patients were studied 6 months later, 7 had hypercalcaemia as defined by the correction factor for a low serum albumin level, and 6 of these patients had raised serum ionised calcium concentrations. Biochemical studies in the 23 patients indicated evidence of hyperparathyroidism, namely, hypophosphataemia, increased serum alkaline phosphatase, hyperchloraemia, and reduced tubular reabsorption of calcium. However, serum immunoreactive parathyroid hormone concentrations were normal. Only one patient had an abnormally low serum 25-hydroxy-vitamin D result: this patient had a high level of urinary D-glucaric acid and was receiving phenobarbitone for treatment of epilepsy. The biochemical features suggestive of parathyroid overactivity were particularly found in patients with raised serum calcium levels. The cause of hypercalcaemia in rheumatoid arthritis remains to be explained.

Liver abnormalities in penicillamine treated rheumatoid arthritis

Liver enzymes were followed in 99 patients treated with D-penicillamine for rheumatoid arthritis. In six abnormalities were found which consisted of elevated levels of lactic dehydrogenase. ALAT/ASAT, alkaline phosphatases or combinations of these. The changes were reversible on stopping the drug with one possible exception. No evidence of biliary cirrhosis, chronic active hepatitis or HBag-associated hepatitis was found. Liver biopsy was performed in 4 cases--one was taken 2 months after the treatment was discontinued, and was normal. One biopsy showed mild inflammatory changes, whereas in two histologic evidence of toxic liver necrosis was present. Liver damage should be included among possible complications of D-PA treatment.

Auto-antibodies in Sjögren's syndrome. With special reference to liver-cell membrane antibody (LMA)

Sera from 70 patients with Sjogren's syndrome (SS), of whom 40 had primary and 30 secondary SS, were tested for various auto-antibodies of the IgG, IgA and IgM classes. 20% had liver-cell-membrane antibody (LMA), 90% had anti-nuclear antibodies (ANA), 40% salivary-gland antibodies (SGA), 13% anti-mitochondrial antibodies (AMA), 33% smooth-muscle cell antibodies (SMA), 9% skeletal-muscle antibodies (SKA) and only 1% had parietal-cell antibodies (PCA). In addition, 53% had IgM rheumatoid factor and 6 patients with anti-DNA antibodies all had SLE. 64% had increased serum IgG, 24% IgA and 14% IgM. A significantly higher incidence of ANA was found within all three Ig classes in patients with secondary SS. AMA and IgM-rheumatoid factor were also found to be elevated in this group. On the other hand, SGA occurred most frequently in patients with primary SS. LMA was mainly of the IgG class and IgG AMA and SMA were more often present in these patients than in those with a negative LMA reaction. The results of the investigation suggest inter alia that inflammatory liver disease, although not indicated by either the case history, physical examination or biochemical values, is probably present in patients with SS.

Gamma glutamyl transpeptidase levels in arthritis: a correlation with clinical and laboratory indices of disease activity

Gamma glutamyl transpeptidase (GGTP) was measured in 62 patients with rheumatoid arthritis (RA) and 27 with osteoarthrosis (OA). The values for GGTP were significantly higher in the subjects with RA compared with the OA group. The prevalence of elevation of GGTP was higher in the RA subjects (77%) than in the OA patients (33%). Levels of GGTP correlated significantly with a number of objective indices of activity of RA in a separate group of 28 patients. Following treatment with penicillamine, GGTP levels showed a significant drop towards normal levels.

Fenbufen compared with indomethacin in osteoarthrosis

A double-blind, crossover clinical trial was carried out with a new propionic acid derivative, fenbufen, versus indomethacin and placebo in 20 patients with osteoarthrosis. Active drug dosages of 75 mg indomethacin daily and 600 mg fenbufen daily were used. Fenbufen scored significantly better than placebo with respect to two and indomethacin better than placebo with respect to five of the assessment indices used. Indomethacin was significantly better than fenbufen with respect to two indices and, overall, appeared more effective in the dosages tested. Biochemical abnormalities of liver function (serum alkaline phosphatase and/or SGOT) were noted in 5 patients after fenbufen therapy (in 3 patients after 4-weeks' treatment and in 2 after 6 weeks) but in none after indomethacin therapy. The significance of these findings is discussed. It is concluded that fenbufen should be withdrawn from further clinical use until the true incidence and significance of hepatotoxicity has been evaluated.

Collagenase at sites of cartilage erosion in the rheumatoid joint

Immunolocalization studies of rheumatoid tissues employing specific synovial collagenase antibody have demonstrated immunoreactive enzyme at the cartilage/pannus junction. Collagenase was not detected in chondrocytes or the cartilage matrix remote from the resorbing front, and relatively little enzyme was observed in the hypertrophied synovial membrane itself. These observations directly support the idea that synovial collagenase participates in cartilage erosion in rheumatoid arthritis.

The influence of drugs and disease activity on biochemical and haematological data in rheumatoid arthritis

Biochemical and haematological data from 218 patients with rheumatoid arthritis were analysed and compared with data from a reference hospital population. The comparison demonstrated significant differences in several biochemical and haematological tests and that the patterns of change are different between males and females. The data were also analysed by conventional statistical methods and discriminant analysis using a computer to establish which tests were most influenced by the activity of the disease and drug therapy. The results obtained demonstrate marked difference between groups of patients with different disease activity or receiving different drugs. The discriminant analysis also identified those tests which differentiate these groups most effectively.

Abnormalities in mineral metabolism suggestive of parathyroid over-activity in rheumatoid arthritis

A three-part study on mineral metabolism in patients with classical rheumatoid arthritis is described. In the first two parts, biochemical abnormalities were revealed suggestive of parathyroid over-activity, and in the third part, observation on calcium absorption provides a hyperparathyroid pattern. The importance of these findings in relation to demineralisation of bone in rheumatoid arthritis is discussed.