Clinical and Radiologic Features, Lung Function and Therapeutic Results in Pulmonary Histiocytosis X

Abstract

Clinical appearance, radiologic findings, lung function and results of corticosteroid therapy were analyzed in 42 adult cases of biopsy-proven pulmonary histiocytosis X. Symptoms were present in only 64%. Using the ILO classification 1980, the evaluation of chest radiographs revealed all categories of profusion, size and shape of nodules. The characteristic ‘ring figures’, i.e. thin-walled cysts, in the parenchyma were detected in 78% of conventional tomographies (n = 27) and in all patients examined by CT (n = 5). In patients with early disease, lung function tests (n = 26) including body plethysmography, pulmonary diffusing capacity and ergospirometry revealed that parameters of gas exchange are most sensitive (T_{L, co} 84%, K_co 72%). Bronchial reactivity to carbachol was significantly higher than in controls (n = 12). Lung perfusion scintigram showed an abnormal, but uncharacteristic pattern in 81% (n = 26). During corticosteroid therapy, no progression was observed (n = 36). 85% of patients with radiographic evidence of progressive disease improved after administration of corticosteroids (n = 14).

Pulmonary Langerhans'-Cell Histiocytosis

“…The overwhelming majority (> 90%) of adult patients who develop PLCH smoke cigarettes or were exposed to substantial second-hand smoke exposure [5,10,12]. In children with PLCH, the association with cigarette smoking is less clear [17], although it has been reported that the commencement of smoking in teenage years can precipitate PLCH in young adults with a history of non-pulmonary childhood LCH [30].…”

“…Although evident that cigarette smoke is the most important factor associated with the development of PLCH, the effects of smoking on Langerhans cell Smoking history Infrequently described [16,17] Reported in > 95% [5,12] Imaging findings; chest CT…”

“…Reduction in DLCO may occur in isolation or accompany restrictive, obstructive or mixed abnormality and is primarily a reflection of pulmonary vascular dysfunction [5,82]. A restrictive pattern is more frequently observed in earlier stages of disease while an obstructive pattern is more common as disease advances, and is the predominant pattern as disease progresses [12,83]. A significant proportion of patients develop progressive decline in DLCO and Forced Expiratory Volume in 1 s (FEV 1 ) within the first few years following diagnosis, and develop severe airflow obstruction [83].…”

“…Pharmacotherapy with immunosuppressive medication should be considered for all adult patients with severe disease, or patients in whom progressive decline in lung function occurs. Corticosteroids in the form of prednisone 0.5-1.0 mg/kg daily with slow tapering over months have historically been employed to treat patients with progressive disease, but it remains unclear as to whether patients objectively respond to corticosteroid therapy [11,12]. Other immunosuppressive agents, including chlorodeoxyadenosine (also known as cladribine or 2-CDA), cyclophosphamide, and methotrexate, have been used to treat progressive disease [89][90][91][92].…”

“…PLCH predominantly affects young adults between the ages of 20 to 40 years [5]. There does not appear to be a gender predilection [5,[10][11][12]. Although most published series in the English literature are composed of Caucasian subjects [5,10,11], its occurrence in Asian populations is increasingly recognized [13].…”