More aggressive treatments such as synovectomy, achieved using intra-articular agents (chemical or radioactive) can provide good results, with efficacy reported for at least 1 year.Reducing acute joint swelling:
Arthrocentesis (or drainage of joint) may be useful to relieve joint swelling and improve range of motion. Local steroid injections can also reduce fluid accumulation short-term, but do not prevent onset of episodes. These treatments provide temporary relief only. Bed rest, ice packs splints and exercise are ineffective.A single case report of a patient with treatment-refractory IH describes the use of anakinra, an interleukin 1 receptor antagonist. At the first sign of any attack, a single 100 mg dose was given. With this dosing at onset of attacks, each episode of effusion was successfully terminated.Reducing frequency and severity of IH episodes:
Case reports indicate some success using long-term, low-dose colchicine (e.g. 0.5 mg to 1 mg daily). A recent single case report has shown hydroxychloroquine (300 mg daily) to be effective too.Small-sized clinical trials have shown positive results with (1) chemical and (2) radioactive synovectomy. (1) Setti et al. treated 53 patients with rifampicin RV (600 mg intra-articular injections weekly for approximately 6 weeks) with good results at 1 year follow-up. (2) Top and Cross used single doses of intra-articular radioactive gold in 18 patients with persistent effusions of mixed causes including 3 with IH. All 3 patients with IH responded well to treatment at one-year follow-up. Prognosis
Once established, periods of remissions and relapse can persist indefinitely. While IH may remit spontaneously for most people the condition is long-lasting.
Effusions are large, restricting range of motion but significant pain is not a feature. There is usually stiffness. Tenderness of the joint may or may not be present. Aspirated synovial fluid is usually sterile but will sometimes show elevated cell count (>100 cells/mL) with 50% being polymorphonuclear leukocytes.Onset of effusions are sudden with no particular trigger or stimulus. Each episode lasts for a few days to about a week and recurs in cycles of 7 to 11 days with extremes of 3 days to 30 days also reported. Sometimes the joint may begin to swell again as soon as the fluid has subsided. Where both knees are affected concurrently, as one joint ceases to swell the other may become involved.The cycle of joints swellings have been reported as being very regular, even predictable. This has been a characteristic feature of IH in many case reports. However, over the longer-term especially, these cycles of effusion and recovery may not be as constant as first reported.In women, many cases seem to begin at puberty. Episodes of knee swelling may coincide the menstrual cycle. In nearly all case reports, pregnancy seems to suppress the condition but after birth, during lactation, it returns.In the main, patients are mostly free of other symptoms. Fever is rare. There no signs of local inflammation or lymphatic involvement. Laboratory tests are generally normal or within reference limits.