The treatment of gout

The Effect of Size of Materials Formed or Implanted In Vivo on the Macrophage Response and the Resultant Influence on Clinical Outcome

Both the chemistry and size of a material formed in vivo, or an implanted biomaterial, can alter the in vivo host response. Within the size range covered within this review, over 1 μm, chemistry is only important if the solid material is unstable and leeching small molecules. The macrophage activity and the resultant inflammatory response, however, are related to the size of the solid material. The premise of this review is that differences in size of the solid material, in different cases, can be the reason why there is some individual-to-individual variation in response. Specifically, the inflammatory response is enhanced when the size is between 1-50 μm. This will be looked at for three configurations: spherical particulate (silicone oil or gel from breast implants), elongated particulate (monosodium urate [MSU] crystals in gout or in kidney stones), and fibers (e.g., polyester used in fabric implants). These specific examples were selected because many still believe that the clinical outcome for each is controlled by the surface chemistry, when in fact it is the size. In each case, specific studies will be highlighted to either show a mechanism for creating different sizes and therefore a differential biological response (first three) or how changing the size and shape (diameter and spacing of fibers, in this example) can affect the response and can help explain the different responses to fabric implants found in vivo within the 1-50 μm size range. It was found that polyester fibers under 70 μm had a significant increase in macrophage response. Further, it was found that compounds found in synovial fluid could limit MSU crystal size. In addition, it was shown that plasma with low triglyceride levels emulsifies silicone oils to a greater extent than plasma with higher triglyceride levels. Therefore, in three cases it appears that differences in the inflammatory response between individuals and between different implants could be explained just by the size of the material formed or implanted.

Treatment of crystal arthropathy--history and advances

The history of gout and the many distinguished historical figures who have suffered the agonies of this crystal deposition disorder have claimed the attention of medical historians like no other disease. Its treatment with uric acid lowering drugs became a twentieth century paradigm for the successful management and prevention of a chronic rheumatic disease, but the colorful history of the treatment of gout and crystal deposition disorders stretches back over 4,000 years.

Radioimmunoassay for colchicine in plasma and urine

A radioimmunoassay for the measurement of colchicine (in quantities as small as 0.05 nanogram) in plasma and urine was developed with the use of an antibody from immunized rabbits. After the intravenous injection of 2 milligrams of colchicine in seven subjects, the calculated zero-time concentration in the plasma was 2.9 +/- 1.5 micrograms per deciliter, and the mean half-time in the plasma was 58 +/- 20 minutes. Declining, but measurable, amounts of colchicine could be detected in urine up to day 9 after the drug was administered.

The influence of allopurinol on renal function in gout

Our data demonstrate that adequate control of uric acid production and serum acid concentration in primary gout arrests further deterioration of renal function and in some instances permits subsequent improvement in renal hemodynamic function even when renal impairment is clearly established. In considering the nature of the lesions of urate nephropathy, our study suggests that control of serum uric acid with drug therapy before renal involvement is apparent might prevent or significantly delay the morbidity and mortality of this complication of primary gout.