Measurement Of Lactate Dehydrogenase And C-reactive Protein In Synovial Fluid Of Patients With Knee Osteoarthritis And Relation Between The Grade Of Radiographic Assessment Of Knee Osteoarthritis

Objective Diagnosis of osteoarthritis (OA) is based upon the clinicalorthopaedic examination and the radiographic assessment, both of whichcan be non-specific and insensitive in early joint disease. Biologicmarkers in synovi fluid can reflect quantitative and dynamic changes ofjoint tissue turnover and represent promising adjunct tools. The aim ofour study was to investigate if there is an increase of lactatedehydrogenase(LDH) and C-reactive protein (CRP) in synivoal fluid of kneeosteoarthritis(OA) and if LDH and CRP can be used to help diagnose kneeOA. We also wished to investigate whether it was possible to distinguisha joint with clinically and radiographically confirmed OA from a healthyjoint by comparing lactate dehydrogenase (LDH) and CRP levels within theknee synovial fluid, we also wish to know the relation between the levelsof LDH and CRP in synovial fluid and Keltgren scale. Methods All patientswith knee OA were random selected at out-patient clinic(OPD)and dividedinto 4 groups accordiong to the grade of radiographic assessment and eachgroup was made up of 10 patients. 10 healthy volunteers made up of thecontrol group. The synovial fluid of 40 patients with knee osteoarthritisand the control group was collected through knee paracentesis and sentfor LDH and CRP determination. The fluid was collected in a sterilevacutainer tube and the enzme level was measured by the Olympus chemistryanalyzer AU-400. Results LDH levels in the synovial fluid of each patientgroup were significantly (P＜0.01) higher than the control group, witha mean of 134. 27±7.42 and 87.2±3.94U/L. And LDH levels was defferentbetween each OA patient group with defferent radiographicgrade (P＜0.01). we also found the levels of LDH increased as radiographicscale of OA improved(P＜0.01) and the LDH congcentration showed strongcorrelat ion with the radiographic grades of OA(r=0.82, P＜0.05). The levelsof CRP in all groups were similar(P＞0.05) and show no correlation withthe radiographic grades of OA(r=0.21, P＞0.05). Conclusions LDH levels inthe synovial fluid of knee OA patient is higher than the volunteer, so wecan presume that LDH concentration could be of diagnostic value for identifying knee osteoarthritis from the healthy Furthermore Thecorrelation between LDH congcentration and radiographic grades suggestsLDH can indicate the severity of knee OA. On the other hand, the CRP levelsin synovial fluid have no value for diagnosisand identifying of knee OA.