Shrinking lung syndrome caused by lupus myopathy

A 22-year-old woman was first diagnosed with systemic lupus erythematosus (SLE) in 1999. Clinical features over several years included arthralgia, mouth ulcers, photosensitivity, alopecia totalis, livedo reticularis, fatigue and World Health Organization (WHO) class V glomerulonephritis on renal biopsy. Immunology showed positive antinuclear antibodies (ANA) but negative anti-dsDNA, extractable nuclear antigen antibodies (ENA) and anticardiolipin antibodies (aCL) antibodies. Treatments included prednisolone, azathioprine, cyclophosphamide, cyclosporine and rituximab. In January 2008, the patient presented with a 3-month history of asthenia, dysphagia and easy fatigability. Laboratory tests revealed a mild hypochromic and microcytic anemia. The creatinine phosphokinase (CPK) was 531 U/l (normal value 30–200), lactate dehydrogenase (LDH) 213 U/l (normal value 100–200). During air breathing P02 was 62 mmHg and PC02 was 51 mmHg. Electrophysiological assessment of peripheral nerves and muscles showed normal motor and sensory nerve conduction with mild decrease in the compound muscle action potential amplitude. A muscle biopsy from deltoides revealed endomisial lymphocytic inflammatory infiltrate with perivascular distribution, myophagia and muscle fibre atrophy (Figure 1). The predominant cell in the infiltrate was TCD4+ (Figure 2). Therapy with oral steroids (30 mg daily) was started. Figure 1. Photomicrograph (original magnification, ×200 ; hematoxylin – eosin stain) showing endomysial infiltrates and muscle atrophy. Figure 2. CD45RO stain (original magnification, ×200) revealing that the inflammatory infiltrate is composed primarily of T lymphocyte memory cells. In May 2009, when …