Regardless of the influence of RA on the VTE in the case above, several other risk factors should be noted, including obesity, oral contraceptive use, family history of VTE and prothrombin gene mutation. Her complicated course would have been difficult to predict upon initial evaluation by rheumatology, but the use of POCUS expedited her care.
As performed above, POCUS for diagnosis of DVT using two-region compression has been shown to be an accurate, reproducible and quickly learned method to detect DVT. In one large study, a limited two-region ultrasound paired with D-dimer strategy was shown to be equivalent to whole-leg ultrasonography for the management of symptomatic patients with suspected DVT.2
Ultrasound use has increased in rheumatology fellowships over the past decade, but has been predominantly limited to musculoskeletal ultrasound (MSUS). A recent survey was sent to various postgraduate training programs to determine the trends in MSUS training in the U.S.3 Formal MSUS training programs were present in 90% of rheumatology fellowships that responded to the survey, and various methods of training were employed, such as didactic lectures, scanning sessions with models or cadavers, interventional sessions and Web-based modules. The program directors surveyed believed that MSUS training was an important aspect of fellowship. Certifications in MSUS exist to further training, and many rheumatologists obtain these and use MSUS frequently in practice.
Although rheumatologists can be thought of as specialists in the study of disorders of the musculoskeletal (MSK) system, many of the diseases seen have extra-articular manifestations that require a multisystem approach to care. MSUS has shown utility in the practice of rheumatology; however, expansion with additional POCUS modalities is feasible.
In the above case, a POCUS DVT scan was performed in the rheumatology clinic. Although the risk of VTE associated with RA can be argued, the clinical scenario of a DVT may be common enough to warrant the addition of this skill by rheumatologists. More established extra-articular manifestations of RA, such as pericardial effusion, congestive heart failure, pleural effusion and even interstitial lung disease (ILD) can also be diagnosed and monitored with POCUS in the ambulatory setting.4
Preliminary studies suggest that physicians with limited training in lung ultrasound using pocket-sized devices can attain a high sensitivity for ILD in RA patients. If confirmed in larger trials, this may lead to reductions in CT scanning for early detection of ILD in this population.
As ultrasound machines have become more portable and affordable, there has been a dramatic increase in ultrasound education among medical schools in recent years, and integrated ultrasound curricula have been developed across the four years of medical school.5 The ultrasound topics covered include bedside echocardiography, vascular, abdominal, lung, MSK, FAST examination and RUSH protocol, among others. Medical students who complete the curriculum rate it as an important component of their education and useful for future practice.