Adults
Mixed connective tissue disease (MCTD)
Overlap of lupus, scleroderma and myositis features with a high-titer anti-U1 RNP.
What to look for
- Raynaud's (nearly universal) and puffy hands
- Arthritis, myositis, esophageal dysmotility
- ILD and pulmonary hypertension, the main long-term risks
- High-titer speckled ANA with anti-U1 RNP
What to do
- Send ANA, anti-U1 RNP, CK, CBC, metabolic panel and urinalysis.
- Get PFTs with DLCO and HRCT (MCTD is in the ACR/CHEST screening group), and an echocardiogram.
- Features can evolve into SLE, SSc or myositis over time, so ongoing specialist follow-up is usually needed.
About this urgency level
Early specialist assessment changes outcomes. Send the usual workup with the referral, but don't hold the referral while waiting for results.
Timeframes are typical targets. Local pathways, capacity and clinical judgment come first.