Pulmonary hypertension not a major feature of early mixed connective tissue disease: A prospective clinicoserological study

Background: Mixed connective tissue disease (MCTD) has features common to lupus, scleroderma and myositis with high levels of antibodies to U1 ribonucleoprotein (U1 RNP). Identification of a high incidence of pulmonary artery hypertension (PAH) has changed its prospect. We report the largest series from India. Settings and Design: Rheumatology unit of a tertiary care centre in India; prospective. Materials and Methods: Patients seen between January 2002 and June 2004, satisfying the Kasukawa criteria were enrolled. All patients had a complete laboratory work-up including pulmonary function test, 2-D echocardiography, and Schirmer's test, antinuclear antibodies (ANA) and antibodies to extractable nuclear antigens. HRCT of chest was done where indicated. All patients were given standard treatment and followed up regularly. Results: Out of 1500 patients, thirteen (one male) were diagnosed to have MCTD. The median follow-up period was 18 months [Interquartile range (IQR) 12-22]. The median age of onset of symptoms was 36 years (IQR 22-39) and the median duration of disease was three years (IQR 1.75-4). The most common manifestation was polyarthritis followed by puffy fingers. Sjogren's syndrome, dysphagia and interstitial lung disease, was present in four, three and two patients respectively. Two patients each had myositis and migraine. None had PAH, serositis or renal involvement. Arthritis, puffy fingers and Raynaud's phenomenon were the most common manifestations at onset. All patients were positive for ANA and anti U1 RNP. Two patients each had antibodies to Sm and SSA. Response to treatment also was noted. Conclusion: Pulmonary artery hypertension is not common in early MCTD.