Ultrasound in Rheumatology

Over the years, the role of subspecialties in internal medicine has expanded. Many procedures, which were previously under the purview of other specialties, have since been mandatory skills to be obtained during subspecialty training. In rheumatology, ultrasound is gaining acceptance as a vital tool in aiding diagnosis and monitoring of therapeutic responses to assisting invasive procedures, for example, intraarticular joint injections.

Ultrasound is an imaging modality that is very operator dependant. The skill of the ultrasonographer can determine the quality of images obtained as well as the interpretation of those grainy images. Even existing grading systems are subjective and reproducibility is suspect. Time constraints during patient consultations can also be a deterrent for busy rheumatologists in performing ultrasounds in clinics.

However, if performed well, it could be a potentially important diagnostic tool. In rheumatoid arthritis for example, early damages to the cartilage can be detected even before any changes in Xrays is evident. Even the microarchitecture of tendons and its surrounding structures can be scrutinised for damages.

Ultrasounds can also be used to aid invasive procedures like intraarticular joint injections. Even a fluid collection of 1mm2 can be aspirated under ultrasound guidance. It can also aid in more accurate delivery of drugs to intended targets, like steroid injections which were previously done blindly.

Guidelines for musculoskeletal ultrasound in rheumatology

MSK ultrasound in rheumatology

Gout: Recent Issues

Several issues were raised and discussed at the recent ARA 2008 meeting.

1. Issues about treating asymptomatic hyperuricemia. Debate remains as to whether we should be treating hyperuricemia to prevent gout. As of now, we do not treat patients who have asymptomatic hyperuricemia

2. The panel discussion in Medscape did highlight the fact that the regular dose of 300mg daily may be a rather conservative dose when the permitted level was up to 800 mg daily. There were concerns about allopurinol hypersensitivity. Nevertheless they still recommended increasing the dose from 300 mg if the hyperuricemia is uncontrolled. In my experience, I have seen several cases of severe allergic reactions from allopurinol itself. There was also little concern about increasing the dose in renal impairment.

3. It was agreed that the main cause of hyperuricemia is iatrogenic especially after the ALLHAT trial advocated the use of thiazide diuretics. In such instances, removing the cause would be the logical choice. Other rarer genetical causes were discussed but will remain a much less common cause.

4. Many of treat allopurinol with colchicine. There was concern about colchicine and its drug interactions. It remains a drug that is usually poorly tolerated.

5. One interesting find is that pegylated uricase had significant results in removing tophi. As of now, it is usually a permanent feature and can only be solved through a plastic surgeon's intervention.

The activity on medscape.
ACR 2008: Treating Chronic Gout: The Challenges of Lowering Serum Urate Levels

Autoantibody Test Cost-Effective in Arthritis Diagnosis??

Autoantibody Test Cost-Effective in Arthritis Diagnosis

NEW YORK (Reuters Health) Oct 17 - Testing for autoantibodies against cyclic citrullinated peptide (aCCP) appears to be an economically feasible approach to early diagnosis of rheumatoid arthritis, and may even allow cost savings, German researchers report . more..

Anti CCP can diagnose rheumatoid arthritis even before clinical symptoms become apparent due to its high specificity for the disease. Similarly, IgM rheumatoid factor has occupied this role for decades before the discovery of anti CCP.

However, the controversy for a developing nation is whether anti CCP should be routinely implemented in our healthcare system. Is it as cost effective as believed.

Anti CCP is not without its drawbacks. There are incidences of false positives.

Positive anti-cyclic citrullinated proteins and rheumatoid factor during active lung tuberculosis.
Elkayam O; Segal R; Lidgi M; Caspi D
Ann Rheum Dis. 2006 Aug;65(8):1110-2. Epub 2005 Dec 16.

OBJECTIVES: To determine the prevalence of anti-cyclic citrullinated proteins (anti-CCP) and IgM rheumatoid factor (RF) in sera of patients with TB compared with healthy controls. PATIENTS AND METHODS: 47 consecutive patients with recently diagnosed active pulmonary TB and 39 healthy controls were studied. Data were collected by questionnaire on clinical features of the disease, duration of symptoms, fever, cough, arthralgia, myalgia, sicca symptoms. Serum samples were collected from patients before starting treatment for TB and frozen at -20 degrees C. Anti-CCP and IgM RF were evaluated by ELISA. RESULTS: The mean (SD) duration of TB related symptoms was 4.4 (1.7) months, 73% had fever, 94% a cough. Rheumatic symptoms were relatively rare: arthralgia (4%), myalgias (4%), eye and mouth dryness (2% and 9%, respectively). Mean (SD) levels of anti-CCP were significantly increased in patients with TB compared with controls: 44.9 (51) IU v 20 (7.3) IU (p = 0.002). Serum levels >40 U were found in 15/47 (32%) patients compared with 1/39 (2.6%) controls (p = 0.002). Mean (SD) serum levels of IgM RF were significantly increased in patients with TB: 17.8 (19) v 4.3 (5) (p<0.0001). IgM RF was positive (>6 IU) in 29/47 (62%) patients v 1/39 (2.6%) controls (p<0.0001). CONCLUSIONS: A significant proportion of patients with active TB have an increased titre of anti-CCP and IgM RF.

AD Department of Rheumatology, Tel Aviv Medical Centre, 6 Weizman Street, Tel Aviv 64239, Israel. oribe14@netvision.net.il

This study shows high false positives in active tuberculosis, a disease which is rather prevalent in Malaysia. Even other connective tissue diseases can give rise to a positive anti CCP.

My opinion is that the current role of anti CCP is to support a diagnosis of rheumatoid arthritis in cases where the diagnosis is difficult and uncertain. Combining both IgM RF and anti CCP improves the specificity of diagnosing the disease.

The consensus remains that rheumatoid arthritis should be diagnosed as early as possible and as aggressive as possible. Prognostication of disease with RF and anti CCP can lend credence to a more aggressive approach involving costly biologic agents.

In Malaysia, it can only be done at selective centers as many hospitals remain unmoved by this test. This test remains unavailable at UMMC. However, most private laboratories do offer this blood test.

Adalimumab Effective in Patients With Total Spinal Ankylosis

Those of us who treats ankylosing spondylitis will realise how difficult it is to treat this inevitably progressive disease. This study suggests improvement in patients with spinal ankylosis given an anti TNF alpha, adalimumab.

One major obstacle in Malaysia remains the cost. Many would argue that ultimately the disease is not cured but only offers symptomatic relief. Would one spend your life savings for some relief of pain? i think not.