Erdheim-Chester disease is a rare multisystem non-Langerhans’ cell histiocytic disorder associated with interstitial lung disease (1).
A 65-year-old female was evaluated because of chronic pulmonary infiltrates. In 1990, she developed recurrent sinus infections with increased alkaline phosphatase. In 1994, she had a skin rash. In 1995, she developed left knee arthralgia, bilateral pulmonary infiltrates; sedimentation rate was 110 mm/1h. Transbronchial biopsy showed non caseating granulomas. She had cholestasis, with normal liver biopsy. Skin biopsy showed granuloma annulare. Antineutrophil cytoplasmic antibodies were negative. In 2002, she also complained of abdominal pain. Sinus biopsy showed mild, non specific inflammation. Chest radiogram and chest computed tomography (CT) showed persistent bilateral infiltrates. A positron emission tomography of the body was negative. Past medical history was significant for eczema, hay fever, chronic allergic rhinitis and osteoporosis. Medications included conjugated estrogens, medroxyprogesterone, ibuprofen, chlorpheniramine, nasal beclomethasone and topical triamcinolone. Family history was unremarkable. She was a never smoker. On review of systems, she was complaining of sinus pressure, rhinorrhea, arthralgias and pruritus. She had no dyspnea, or other respiratory symptoms. On physical examination, she had nasal congestion. Jugular vein pressure was normal. Lungs were clear. Cardiac auscultation was normal. Abdomen was negative. There was no clubbing, cyanosis or edema. There was a diffuse annular rash. Pulmonary function test showed decreased diffusing capacity [13.8 (63%)]. Her hemoglobin was 10.9 g/dL, C-reactive protein 12.2 mg/dL, alkaline phosphatase 530 Units/L, antinuclear antibodies 1 Unit. CT of the chest, abdomen and pelvis (picture 1) showed pulmonary infiltrates, mediastinal and retroperitoneal lymphadenopathy, and diffuse perinephric soft tissue masses. Open lung biopsy (picture 2) showed diffuse interstitial fibrosis accentuated along lymphatic pathways with a mixed inflammatory infiltrate including prominent interstitial histiocytes without well formed granulomas. The histiocytes were mostly foamy, and co-expressed CD68 ans S-100. Occasional multinucleated giant cells, Touton type, were also seen. These findings were diagnostic of Erdheim-Chester disease. Silver and auramine rhodamine stains were negative. She was discharged without treatment. Six months later she was doing well.
A case of Erdheim-Chester disease with pulmonary involvement is presented. The rarity of the disease associated with the paucity of symptoms in comparison with the extensive lesions seen on the chest CT explain at least in part the delay in diagnosis. It also indicates a relatively good prognosis compared with what is usually found in the literature. Symptoms usually include dyspnea, and dry cough. Chest radiogram shows diffuse interstitial infiltrates, with upper zone predominance. On chest CT, the most common findings include an interstitial process characterized by smooth interlobular septal thickening and centrilobular nodular opacities, fissural thickening and pleural effusions (2). Lung biopsy specimens show foamy histiocytes, lymphocytes, and scattered Touton giant cells with associated fibrosis in a striking lymphatic distribution. The infiltrate involves visceral pleura, interlobular septa, and bronchovascular bundles. Immunohistochemical stains are positive for CD68 and commonly for S-100 protein. Stains for CD1a are negative (1). S-100 positivity may be more typical of Rosai-Dorfman disease but typical features of large histiocytes with emperipolesis were not seen here. Treatment is not well standardized and may include corticosteroids, chemotherapy, radiation, immunomodulating agents and stem-cell transplantation.
In this case, the lack of respiratory symptoms and the duration of the disease suggested that observation without treatment was a reasonable option. The skin lesions were likely related to the disease.
P.R. Bauer, None.