[Acute monoarthritis in a third level hospital].

Introduction: Acute monoarthritis (AM) represents a relevant cause of morbidity that requires prompt medical care. The study of synovial fluid becomes relevant to allow a rapid diagnostic approach. The main objective of the study was to determine the frequency and clinical-analytical characteristics of episodes of AM and acute bursitis evaluated in a hospital during a period of 6 years.
Methods: Cross-sectional retrospective analytical study in a hospital at Córdoba, Argentina. All episodes of acute monoarthritis and bursitis that occurred in patients aged 18 years or older between 2012 and 2017 were included. AM in pregnant women and chronic monoarthritis were excluded.
Results: One hundred and eighty episodes of AM and 12 of acute bursitis were included. Among the AM, 120 (66.7%) occurred in male patients and the average age was 62.1±16.9 years. The main cause of AM was septic, identifying 70 (36%) cases, followed by microcrystalline AM identify 54 (28%) cases, which corresponded to gout and calcium pyrophosphate dihydrate (CPPD) with 27 (14%) cases each one. Monosodium urate crystals were identified in 26 (14.3%) patients, CPPD in 28 (15.6%) and cholesterol in 1 (0.6%).
Discussion: The main cause of AM was septic arthritis, followed by microcrystalline AM (gout and secondary to CPPD). The main affected joint was the knee, followed by the shoulder. Synovial fluid analysis was a key element when making the differential diagnosis between the different causes of acute monoarthritis and bursitis.