A 59-year-old right-hand–dominant man with hypertension, obesity, and gout presented to the emergency department with sudden onset of atraumatic left elbow pain 1 day previously. He had a history of gout attacks in both ankles and feet but had no previous attacks in the upper extremities. Range of motion of the elbow had been limited since the onset of pain. He started taking allopurinol 300 mg daily 1 week before presentation. The patient had been previously diagnosed with gout, although he had stopped taking his allopurinol for unclear reasons. His primary care physician noted this and had him restart it.
Physical examination in the emergency department showed an alert, obese male in no acute distress. Temperature was 99.7º, blood pressure 140/83 mm Hg, heart rate 90 beats/min, respiratory rate 20 breaths/min, and oxygen saturation 97% on room air. Diffuse swelling, tenderness, and erythema were noted in the left elbow. Elbow range of motion was 30º short of full extension to 80º of flexion, with pain at the extremes of motion. Results of blood tests were as follows: white blood cell count, 13.0×109/L with 80% neutrophils; hemoglobin, 11.0 g/dL; serum sodium, 140 mmol/L; serum potassium, 3.5 mmol/L; serum chloride, 106 mmol/L; serum bicarbonate, 22 mmol/L; serum urea nitrogen, 28 mg/dL; serum creatinine, 1.5 mg/dL; serum glucose, 104 mg/dL; serum calcium, 8.4 mg/dL; and uric acid, 6.5 mg/dL. Radiographs of the left elbow showed joint effusion (Figure 1).
Preoperative anteroposterior (A) and lateral (B) radiographs of the left elbow showing joint effusion but no evidence of trauma.
The possibility of septic arthritis in the left elbow prompted immediate arthrocentesis. Under sterile conditions, the elbow was aspirated with an 18-gauge needle via a lateral portal, yielding 9 mL dark yellow fluid. No gross purulence was seen. At that time the joint was also flushed with saline. The aspirate was sent for Gram stain and culture, cell count, and total protein and crystal analysis. Gram stain analysis showed many polymorphonuclear leukocytes but no organisms. Cell count showed 168,500 white blood cells/µL with 89% segmented neutrophils. Because of the markedly elevated white blood cell count, the patient was given empiric antibiotic treatment with vancomycin and piperacillintazobactam). Synovial fluid analysis was performed the next day (hospital day 1) and showed innumerable monosodium urate crystals. Cultures of the synovial fluid were evaluated for aerobic, anaerobic, fungal, and acid-fast bacteria, and final cultures showed no growth. Antibiotics were discontinued on hospital day 2 because of the negative culture and rheumatologic findings consistent with gout. Oral prednisone taper was initiated on hospital day 1, and allopurinol was continued at the recommendation of the rheumatology service. The patient was unable to take nonsteroidal anti-inflammatory drugs because of chronic kidney disease. Pain decreased and range of motion gradually increased after the initiation of prednisone treatment. The patient was discharged on hospital day 4 with rheumatology follow-up, with markedly improved elbow motion that had returned to normal.
A 69-year-old man presented to the emergency department with gradual onset of left knee pain and swelling over the preceding 4 days. Medical history was significant for insulin-dependent diabetes mellitus, hypertension, obesity, obstructive sleep apnea, and a cerebrovascular accident in 1993, with residual left lower-extremity weakness. The patient had no antecedent trauma, recent illness, fevers, or chills. He reported several previous instances of gout attacks, 1 time in the left knee, but the current symptoms were much more severe than he had experienced in the past. Since the onset of pain, range of motion and ability to bear weight had decreased dramatically, and he could no longer ambulate on presentation to the emergency room. The patient noted that he was not currently taking nor had he in the past taken any medications (nonsteroidal anti-inflammatory drugs, colchicine, allopurinol) to treat gout.
Physical examination in the emergency department showed an alert, obese male in moderate distress. Temperature was 100.8°, blood pressure 179/83 mm Hg, heart rate 140 beats/min, respiratory rate 18 breaths/min, and oxygen saturation 96% on room air. Examination of the left lower extremity was notable for diffuse swelling and erythema around the knee, marked tenderness to palpation over both the medial and lateral aspects of the knee as well as anteriorly, and severely limited range of motion (15°–20° of flexion) secondary to pain. Findings on neurovascular examination were largely unremarkable. Results of blood tests were as follows: white blood cell count, 6.1×109/L with 66% neutrophils; hemoglobin, 13.9 g/dL; serum sodium, 140 mmol/L; serum potassium, 3.7 mmol/L; serum chloride, 105 mmol/L; serum bicarbonate, 20 mmol/L; serum urea nitrogen, 15 mg/dL; serum creatinine, 1.43 mg/dL; serum glucose, 174 mg/dL; and serum calcium, 9.6 mg/dL. C-reactive protein, erythrocyte sedimentation rate, and uric acid levels were all elevated at 95 mg/L, 35 mm/h, and 9.7 mg/dL, respectively. Radiographs of the left knee were significant for marked tricompartmental degenerative osteoarthritis with mild joint effusion (Figure 2).
Preoperative anteroposterior (A) and lateral (B) radiographs of the left knee with tricompartmental arthrosis.
Concern about septic arthritis as well as deep venous thrombosis prompted urgent lower-extremity Doppler ultrasound examination along with arthrocentesis of the left knee, both of which were performed in the emergency department. Ultrasound of the bilateral lower extremities was negative for deep venous thrombosis. Arthrocentesis of the left knee yielded 20 mL turbid-appearing fluid that was sent for cell count, culture, and Gram stain as well as rheumatologic evaluation. Synovial fluid collection was performed before administration of oral or intravenous antibiotics. Cell count showed 500,000 white blood cells/µL with 87% segmented neutrophils and 5000 red blood cells/µL. Gram stain and culture showed no polymorphonuclear leukocytes and no organisms. Because of the markedly elevated white blood cell count, the patient was given empiric antibiotic treatment with vancomycin and piperacillin-tazobactam and scheduled for urgent arthroscopic irrigation and debridement for presumed left knee septic arthritis.
Intraoperative arthroscopic evaluation of the knee joint showed mildly purulent effusion with diffuse, severe inflammation of the synovium and extensive damage to the cartilage on the articular surfaces of both the femur and the tibia. The synovium was debrided and the joint irrigated copiously with 12 L normal saline. The patient tolerated the procedure well, with no intraoperative complications. Synovial fluid analysis was completed the next day (hospital day 1) and showed scattered intracellular negatively birefringent needle-shaped crystals visualized under polarized light microscopy, consistent with monosodium urate crystals, suspicious for acute gout.
Postoperatively, the patient’s symptoms improved gradually with appropriate pain control, including careful use of non-steroidal anti-inflammatory drugs, physical therapy, and continued intravenous antibiotics, as per the recommendations of the infectious disease team. On postoperative day 3, the patient had regained almost full painless motion of the left knee, achieving 0° to 120° of flexion and extension with only very mild residual pain on maximum flexion. Findings of final joint fluid cultures were negative.