Article

75-Year-Old Filipino Man With Knee Effusion and Pus on Joint Aspiration

Returning from the Phillipines, the patient came to the clinic with atraumatic right knee swelling and loss of range of motion. He arrived in a wheelchair. He had osteoarthritis, but denied any constitutional symptoms. Joint aspiration produced grossly milky white pus. What's going on?

A 75-year-old Filipino man presented to the ambulatory medicine clinic with two days of atraumatic right knee swelling and loss of motion. 

He had returned from the Philippines one week previously.  He denied any constitutional symptoms such as fevers, chills, or night sweats. 

His pertinent past medical history was significant only for osteoarthritis.  He had become wheelchair-bound, and his examination revealed an asymmetric right knee effusion.  There was obvious erythema that was warm to the touch. Crepitus was elicited bilaterally. 

Passive and active range of motion in his right knee were limited, and it was tender to palpation. 

Joint aspiration produced grossly milky white pus with some blood streaking due to a mildly traumatic tap. The image above shows what was seen in the aspirate.

What would you include in the differential? Which tests would you have ordered?

What's your guess at the diagnosis (and will you guess wrong initially, like the authors)?

Click here for the full case report and discussion.

Related Videos
Orrin Troum, MD: Accurately Imaging Gout With DECT Scanning
John Stone, MD, MPH: Continuing Progress With IgG4-Related Disease Research
Philip Conaghan, MBBS, PhD: Investigating NT3 Inhibition for Improving Osteoarthritis
Rheumatologists Recognize the Need to Create Pediatric Enthesitis Scoring Tool
Presence of Diffuse Cutaneous Disease Linked to Worse HRQOL in Systematic Sclerosis
Alexei Grom, MD: Exploring Safer Treatment Options for Refractory Macrophage Activation Syndrome
Jack Arnold, MBBS, clinical research fellow, University of Leeds, Leeds Institute of Rheumatic and Musculoskeletal Medicine
John Tesser, MD, Adjunct Assistant Professor of Medicine, Midwestern University, and Arizona College of Osteopathic Medicine, and Lecturer, University of Arizona Health Sciences Center, and Arizona Arthritis & Rheumatology Associates
Gaith Noaiseh, MD: Nipocalimab Improves Disease Measures, Reduces Autoantibodies in Sjogren’s
Laure Gossec, MD, PhD: Informing Physician Treatment Choices for Psoriatic Arthritis
© 2024 MJH Life Sciences

All rights reserved.