Diagnostic Considerations
When evaluating a patient with suspected septic arthritis, also consider conditions such as primary rheumatologic disorders (eg, vasculitis, crystalline arthritides), drug-induced arthritis, and reactive arthritis (eg, postinfectious diarrhea syndrome, postmeningococcal and postgonococcal arthritis, arthritis of intrinsic bowel disease [15] ).
In early disseminated gonococcal infection, an early tenosynovitis predominates without actual joint invasion such as occurs in the later variety of disseminated gonococcal infection. A viral syndrome usually produces polyarticular arthritis. Pustular lesions are consistent (as is almost any type of skin lesion) with staphylococcal bacteremia. Whenever vesicles are present, always consider staphylococcal infection.
Unlike salmonella osteomyelitis, the frequency of salmonella septic arthritis is not greatly increased in patients with sickle cell anemia. However, when septic arthritis does occur, Salmonella is more commonly identified.
Staphylococcus aureus remains the most common infectious agent in people who abuse intravenous drugs. However, a high rate of infections with gram-negative organisms, especially Pseudomonas aeruginosa and Serratia species, occurs in cases of septic arthritis. In addition, a higher rate of fungal and anaerobic infections occurs. Unusual locations, such as the sternoclavicular joint, are involved.
-
A 30-year-old man who was taking steroids presented with a joint effusion and knee pain. Anteroposterior view of the knee demonstrates patchy demineralization of the tibia and femur and joint-space narrowing. This was caused by tuberculoid infection of the joint.
-
Septic arthritis. Anteroposterior view of the shoulder demonstrates subchondral erosions and sclerosis in the humeral head. These are relatively late findings of septic arthritis. Periosteal reaction due to coincident osteomyelitis is present adjacent to the surgical neck of the humerus.
-
During the progression of infectious arthritis of the hip, this image was obtained early in the disease and shows only concentric joint-space loss.
Tables
| Virus | Clinical Features of Viral Disease–Associated Arthritis |
| Parvovirus B19 | Occurs in adult women with erythema infectiosum, often an itchy rash |
| Hepatitis A | Muscle aches and rash in 10% of cases |
| Hepatitis B | Onset in the preicteric phase; usually resolves as jaundice develops; chronic arthritis possible in patients with chronic hepatitis B infection |
| Hepatitis C | History similar to hepatitis B joint infection; usually associated with cryoglobulinemia |
| Rubella (natural infection and vaccine related) | Onset is possible before, during, or after the appearance of the rash; usually resolves in a few weeks; may recur and, more commonly, may persist |
| Human immunodeficiency virus [HIV] (2 types occur, both with noninflammatory, sterile joint fluid) | Develops over several days, and severe knee or ankle pain is characteristic; excellent response to nonsteroidal anti-inflammatory agents (NSAIDS) |
| Sudden onset of severe pain in the shoulders and elbows, closely resembling an acute gouty attack; Opiates often necessary to control pain | |
| Mumps | Occurs in adult men 2 weeks after the presentation of parotitis |
