Penicillamine

Drug-induced glomerulopathies

Normal renal function depends upon an intact glomerular apparatus. Many drugs and chemicals are capable of damaging the glomerulus, causing its increased permeability to large molecules. Glomerular lesions are usually responsible for proteinuria and the nephrotic syndrome. This also holds true for the drug-induced glomerulopathies, of which membranous glomerulo-nephritis is the most frequent type of lesion encountered. Apart from this, several cases of different glomerular changes such as focal segmental glomerulosclerosis and crescentic glomerulonephritis have also been reported. The drug-induced glomerulopathies are probably immune mediated. This is, for instance, reflected in the fact that patients with drug-induced nephritic syndrome frequently have the HLA-B8 and DR3 antigens. In depth information is provided for the previously mentioned disorders.

Effects of antirheumatic agents on cytokines

A review of the literature concerning the effects of traditional antirheumatic drugs on cytokines and the cytokine and anticytokine approaches already used in the therapy of rheumatoid arthritis (RA) is presented. Many antirheumatic drugs are capable of cytokine modulation in vitro. Corticosteroids inhibit the transcription of a broad spectrum of genes including those encoding monocyte, T cell-derived cytokines and several hemopoietic growth factors, whereas drugs such as cyclosporin A and D-penicillamine interfere with T cell activation more specifically by suppressing interleukin 2 (IL-2) production. The in vivo effects of drug therapy on cytokines in RA patients are less well established. Gold compounds reduce circulating IL-6 levels and the expression of monocyte-derived cytokines, such as IL-1, tumor necrosis factor (TNF), and IL-6, in the rheumatoid synovium. Decreases in circulating IL-6, soluble IL-2 (sIL-2R), and TNF receptors and in synovial fluid IL-1 levels have been reported with methotrexate. Reductions in circulating IL-6 and sIL-2R concentrations have also been observed with cyclosporin and corticosteroids, whereas azathioprine reduces IL-6 but not sIL-2R. Studies on sulfasalazine are conflicting and the in vivo effects of D-penicillamine and antimalarials have not been studied yet. Interferon gamma therapy is not effective in RA but may prove a useful antifibrotic for systemic sclerosis. Colony stimulating factors improve the granulocytopenia associated with Felty's syndrome or drug toxicities but can induce arthritis flares and should be reserved to treat infectious complications. Promising results are being obtained with selective antagonism of TNF and IL-1 in RA, and combinations of anticytokine strategies with traditional antirheumatic drugs have been already envisaged. These should preferably be based in a broader knowledge of the effects of antirheumatic agents on the cytokine network.

The nephrotoxic potential of drugs and chemicals. Pharmacological basis and clinical relevance

Scores of drugs in common clinical use are capable of inflicting various degrees of damage to the kidney. Similarly, a large number of widely employed chemicals may adversely affect renal tissue as part of their toxic potential. A xenobiotic may damage the kidney by more than one mechanism. For example, NSAIDs may cause decreased renal perfusion, interstitial nephritis, primary glomerulopathy and/or altered potassium homeostasis. A large number of drugs and chemicals inflict their damage on the renal tubular cell secondary to intracellular accumulation to concentrations substantially higher than in the plasma or in other tissues. These include aminoglycosides, mercury and carbon tetrachloride and cephaloridine. Drug-induced interstitial nephritis is characterised by inflammatory lesions of the renal interstitium developed after at least 7 to 10 days of therapy. The immunological nature of this reaction is suggested by the associated fever, maculopapular rash and arthralgia observed in some of the patients. Although eosinophilia, eosinophiluria, and raised blood IgE levels are characteristic, immunoglobulins are not deposited in renal tissue, and the basic mechanism has not been elucidated. Renal biopsy demonstrates oedema and interstitial inflammatory reaction, mainly with lymphocytes, monocytes, eosinophils and plasma cells. Less frequent, vasculitis of small vessels or granulomatous reaction may develop, leading to necrotising glomerulonephritis. The drugs most commonly causing acute interstitial nephritis are methicillin, ampicillin, cephalosporins, rifampicin (rifampin), sulphonamides, phenindione and allopurinol. Other penicillins, NSAIDs, phenytoin, thiazides and frusemide (furosemide) are less frequently associated with this syndrome. Drugs and chemicals may affect renal function by pharmacologically decreasing glomerular filtration rate and/or renal blood flow. These include the NSAIDs, radiological contrast media and cyclosporin. Normal renal function depends upon an intact glomerular apparatus. Many drugs and chemicals are capable of damaging the glomerulus, causing its increased permeability to large molecules such as proteins. Several drugs including d-penicillamine, thiopronine, captopril, pyrithioxine and methimazole, are believed to exert their damage through their sulfhydryl group which bind with high affinity to glomerular structures. A variety of xenobiotics or their metabolites may be deposited in the renal tubule causing obstruction of urine flow and a secondary damage to tubular epithelium. Sulphonamides, methotrexate and ethylene glycol are good examples.(ABSTRACT TRUNCATED AT 400 WORDS)

Proteoglycan biosynthesis by rabbit articular chondrocytes treated with D-penicillamine

Rabbit articular chondrocytes in confluent monolayer cultures were treated with D-Penicillamine (D-Pen) during 3 or 5 days. The [35S]-sulfate incorporation in neosynthesized proteoglycans was not modified by D-Pen doses ranging from 50 to 800 micrograms/ml. After treatment during 5 days with D-Pen concentrations of 50 or 400 micrograms/ml, the chemical characteristics of proteoglycans from medium and cell-layer were determined. The aggregation capacity of proteoglycans from medium, the monomer molecular size, the glycosaminoglycan chain length and the relative rates of the different glycosaminoglycans (chondroitins, chondroitin 6-sulfate, chondroitin 4-sulfate, hyaluronic acid) remained unchanged. These results suggest that D-Pen does not alter some of the cartilage mechanical properties due to the presence of proteoglycans.

D-penicillamine in patients with rheumatoid arthritis. Serum levels, pharmacokinetic aspects, and correlation with clinical course and side effects

After administration of D-penicillamine to patients with rheumatoid arthritis, measurements of serum level and urinary excretion showed half-life times of 1.6 hours in the rapid phase and 4-6 days in the slow phase. The latter evidence suggests that tissue pooling occurs. With a dosage of 750 mg/day, basic serum levels of 100 microM are gradually reached. Serum D-penicillamine levels were shown to be the same for patients who responded well to treatment, those who did not respond, and for patients who had adverse side effects as well as those who had none. Intestinal resorption decreased when D-penicillamine was taken close to meals and was greatly reduced by iron preparations.

Thrombokinetics in patients with rheumatoid arthritis treated with D-penicillamine

The mechanism of D-penicillamine induced thrombocytopenia in rheumatoid arthritis was investigated by measuring platelet life-span and platelet production rate in 2 groups of rheumatoid arthritis patients treated with 250-750 mg/day D-penicillamine, 14 with a normal platelet count and 9 with thrombocytopenia (platelet count 50-130 X 10(9)/1). Age matched control patients not treated with D-penicillamine included 14 with rheumatoid arthritis and 9 with osteoarthritis. The platelet life-span was normal, but platelet production rate was significantly reduced in the thrombocytopenic patients, suggesting that D-penicillamine causes thrombocytopenia through bone marrow suppression.

Prolonged treatment with D-penicillamine: effects on adjuvant arthritis in the rat

The effects of long term D-penicillamine treatment on adjuvant arthritis in the rat were determined in order to establish a possible approach to the laboratory evaluation of anti-rheumatic drugs. Oral pretreatment (1-3 months) followed by continued through-treatment on a daily basis (100 mg/kg p.o.) failed to modify the parameters tested: viz. (a) body weight changes; (b) primary paw lesions; (c) secondary hind paw lesions; (d) secondary forepaw, ear and tail lesions; (e) the number of 'responders'. Autopsy showed no macroscopic abnormalities in the lungs, heart, thymus, liver, spleen, adrenal glands, kidneys and gastro-intestinal tract. These results are discussed in relation to previous findings whereby rat adjuvant arthritis, in addition to other experimental immune reactions, has been suggested as an indicator for D-penicillamine activity.

Cutaneous manifestations of rheumatoid arthritis

Rheumatoid arthritis is a systemic disease which can have multiple cutaneous manifestations. In particular, rheumatoid vasculitis may be difficult to diagnose because of the wide array of clinical presentations. Early recognition can assist the physician in diagnosis and in determination of the proper therapy. Every physician caring for patients with rheumatoid arthritis should be aware of these common dermatologic complications.

Reversible gynaecomastia associated with D-penicillamine in a man with rheumatoid arthritis

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Clinical trial of penicillamine in rheumatoid arthritis

The medical records of our first 200 consecutive rheumatoid arthritis patients treated with penicillamine were analyzed retrospectively. All but 5 patients (97.5%) had undergone earlier chrysotherapy that resulted in either therapeutic failure or toxicity. Only 57 patients (28.5%) were still receiving penicillamine on January 1, 1981, and the duration of therapy ranged from 23 to 62 months. The dropout rate due to toxicity, therapeutic failure, relapse, or other reasons was very high (71.5%). Toxic effects required permanent discontinuance in 56 patients (28%). Therapy was discontinued for 36 patients (18%) because of no benefit. A striking number (20) had relapse after therapeutic success and while continuing to take penicillamine, and the therapy had to be discontinued, a relapse rate of 10%. Therapy for the remaining 15.5% was discontinued for miscellaneous reasons that were not related to penicillamine per se: patient anxiety (6%), lost to followup (5%), hospitalization for reasons unrelated to penicillamine therapy (2%), lack of cooperation and study protocol (1% each), or pregnancy (0.5%). By our criteria, 142 patients (71%) received benefit (remission or improvement). Therapy results for these patients were as follows: still on penicillamine on January 1, 1981 (28.5%); no longer receiving the drug due to toxicity (19.5%); no longer receiving penicillamine due to relapse while on continuing therapy (10%); no longer receiving penicillamine due to miscellaneous reasons not related to penicillamine therapy (13%). This study shows that penicillamine is a valuable drug in the treatment of rheumatoid arthritis, but its value in clinical practice is limited by a rather high incidence of both toxicity and relapse during treatment.