Clinical implications of synovial fluid specimen handling for crystal associated arthritides: A systematic review

Synovial fluid crystal analysis with compensated polarization using a gout analyser in clinical practice

OBJECTIVE

To validate the gout analyzer as a clinical method of synovial fluid crystal analysis.

METHODS

Thirty knee synovial fluid samples with suspected calcium pyrophosphate (CPP) crystals were analyzed. Within 48 hours after collection, each non-centrifuged sample was examined blindly and independently by one or more rheumatologists in the following order: 1) with an optical microscope under ordinary light, 2) with the same microscope under compensated polarization provided by a gout analyzer, and 3) with a fully equipped compensated polarized microscope with a rotating stage as the gold standard. As a reference, laboratory technicians analyzed fresh, centrifuged synovial fluid using a gout analyzer.

RESULTS

Of the 30 samples analyzed, CPP and monosodium urate (MSU) crystals were detected in 11 and four, non-centrifuged samples, respectively, using a fully equipped compensated polarized microscope. The rheumatologists' detection rate of crystals in the non-centrifuged synovial fluid under ordinary light and with a gout analyzer was 73.3% and 80%, respectively. The laboratory technicians' detection rate in fresh centrifuged synovial fluid using a gout analyzer was 100%.

CONCLUSION

A gout analyzer may be used to diagnose gout and calcium pyrophosphate deposition disease definitively if a fully equipped compensated polarized microscope is unavailable.

Diagnosis, Treatment, and Outcomes of Crystalline Arthropathy in the Setting of Total Knee Arthroplasty: A Critical Analysis Review

» Emerging evidence suggests the prevalence of crystalline arthropathy (CA) in the setting of total knee arthroplasty (TKA) is increasing, and diagnosis of CA is often intricate because of symptom overlap with other common postoperative complications such as periprosthetic joint infection (PJI). Consequently, an accurate and timely diagnosis becomes pivotal in guiding the choice of treatment.» CA includes gout and calcium pyrophosphate deposition (CPPD) disease, and accurate diagnosis in patients with prior TKA requires a multifaceted approach. The diagnosis algorithm plays a critical role in determining the appropriate treatment approach.» Management of CA typically involves a conservative strategy, encompassing the administration of nonsteroidal anti-inflammatory drugs, colchicine, and steroids, regardless of whether patients have undergone prior TKA.» There is conflicting evidence on the effect CA has on the surgical outcomes in postoperative TKA patients. While these patients may expect excellent functional outcomes and pain relief, they may be at a higher risk of complications such as infections, medical complications, and revision procedures.» Additional research is required to fully comprehend the impact of CA on postoperative TKA outcomes and to establish effective strategies for enhancing patient care and optimizing long-term joint function.

The Persistency and Visibility of Synovial Fluid Crystals After at Least 10 Days in Refrigerator by Light and Polarized Microscopy

Introduction

Synovial fluid (SF) analysis is one of the most important tests used in approach to arthritis and is necessary for rheumatology fellowship training. It depends on the operator's experience and can be affected by handling, processing, temperature, type of preservative, and time from aspiration to analysis. Therefore, we aimed to reevaluate the SF with positive results for crystals, after at least 10 days for the persistency and visibility of the crystals.

Method

For 1 year, we reevaluated crystal positive synovial fluid samples after at least 10 days under light and polarized microscopy. The samples were sent in tubes without any preservative. After the first day of diagnosis of a crystal arthropathy, all the samples were kept in 4 °C refrigerator in a syringe without any preservative and then reevaluated.

Results

14 calcium pyrophosphate (CPP); 12 monosodium urate (MSU), 1 of which was combined CPP and MSU; and 1 post-methylprednisolone (Depomedrol) injection, steroid crystal arthropathy were found and reevaluated. In all reevaluated samples [between 10-24 (median:14 days)], the crystals were detectable again.

Conclusion

Our results suggests that SF CPP, MSU and methylprednisolone crystals at 4 °C without preservation could be detectable after 10-24 days (median: 14, 15.5, and 10 days, respectively) under light and polarized microscopy. It seems that the samples evaluated in emergency settings without enough time and those sent from other centers or gathering samples for trainees can be kept to detect crystals at least 10 days for all and till 22 days (for CCP and MSU) after sampling.