RESUMEN
Alkaline phosphatase [ALP], alkaline pyrophosphatase [APP], calcium [Ca] and phosphorus [p] were estimated in the serum of 50 arthritic patients who were divided into 4 groups: Osteoarthritis [OA], Rheumatoid arthritis [RA], Systemic lupus erythematosus [SLE] and. Gouty arthritis [GA] and a control group of 15 healthy individuals. ALP was estimated using Nitron-phenylphosphate as a substrate, while APP was determined using Sodium pyrophosphate as a substrate. On the other hand, Ca and P were determined colorimetrically. The obtained results of the serum ALP showed a significant increase in GA, RA and. SLE patient groups, while in OA group, there was a non significant increase. Serum APP showed a highly significant increase in the four groups. Serum Ca showed a non significant decrease in the four groups. Lastly, serum P showed a significant increase in OA, RA and SLE groups, while it showed a non significant increase in GA group