Good Morning !October 3rd, 2011

Mixed Connective Tissue Disease

An overlap syndrome associated with anti-U1-RNP (ribonucleic protein) antibodies with features of SLE, scleroderma, and polymyositis

In early stages, cannot be differentiated from the other connective tissue diseases (SLE, Scl, PM, DM, RA, and Sjogren’s)

Is MCTD a specific disease?

Early symptoms › Easy fatigability› Poorly defined myalgias› Arthralgias› Raynaud phenomenon

Major reason to consider MCTD a distinct entitiy

For patients with high RNP antibodies:› Seldom develop glomerulonephritis,

cerebritis, psychosis, or seizures› Nearly always have development of

Raynaud phenomenon› More likely to develop pulmonary

hypertension› More likely to be RF positive (in 70%) and

develop erosive arthritis

Clinical features

4 features that suggest MCTD rather than another disorder:› Raynaud and swollen hands› Absence of renal and CNS disease› More severe arthritis› PHTN› RNP antibodies

More common in women (16:1) Present in 2nd or 3rd decade

Clinical features (cont.)

Skin manifestations› Discoid plaques and malar rash

Fever of unknown origin Arthritis is severe

Clinical features (cont.)

Myositis and myalgia

Cardiac disease› RVH› Right atrial enlargement› Conduction defects› Pericarditis (10 to 30%)

Clinical features (cont.)

Pulmonary involvement (75%)› Effusions› PHTN

Screen for with echo› Interstitial lung disease (30 to 50%)

See septal thickening, ground-glass opacities, nonseptal linear opacities, and lower lobe predominance on CT scan

› Infections› Vasculitis

Clinical features (cont.)

Absence of severe renal disease› High titers of RNP antibodies may be

protective GI involvement in 60 to 80%

› Hypomotility› Serositis› Mesenteric vasculitis› Pancreatitis

CNS› Trigeminal neuropathy› Headaches

Lab abnormalities

Low grade anemia Leukopenia Hypergammaglobulinemia RF positive Anti-cyclic citrullinated peptide (CCP)

antibodies + ANA RNP antibodies

Treatment

Thought to be incurable Some features are responsive to

glucocorticoids Antimalrials or methotrexate should be

used in patients requiring repeated or ongoing steroids

Treat specific features (NSAIDS for arthritis, etc.)

Prognosis

Mortality is 16 to 18% at 10 to 12 years Major cause of death is progressive

pulmonary hypertension

Noon ConferenceRadiology