Foreign-Body-Induced Pulmonary Vasculitis (Cellulose and Talc Granulomatosis)

Fig. 9.2 Cellulose granulomatosis (foreign-body-induced pulmonary vasculitis) in a 37-year-old man who is a drug abuser. (a) Thin-section (1.5- mm collimation) CT scan obtained at level of left interlobar pulmonary artery shows diffuse pulmonary involvement with ill-defined centrilobular

small nodules (arrows). Note also nodular branching structures (tree-in- bud sign). (b) Low-magnification (×40) photomicrograph demonstrates necrotizing vasculitis at the central portion of secondary pulmonary lobule (arrow) (Reprinted from Han et al. [3] with permission)

Table 9.1 Common diseases manifesting as tree-in-bud sign

Foreign-Body-Induced Pulmonary Vasculitis

(Cellulose and Talc Granulomatosis)

Pathology and Pathogenesis

Intravascular foreign materials and their associated granulomatous reaction in vessel walls cause tree-in-bud appearance at CT. Materials responsible for this disorder include insoluble particles such as microcrystalline cellulose, talc, and corn starch, which are used as fillers in tablets taken orally. These substances become trapped in the pulmonary vasculature, causing thrombosis, inflammation, and eventually giant cell reaction [3] (Fig. 9.2).

Centrilobular nodules and tree-in-bud patterns reflect the bronchiolar distribution of aspirated material.

Patient Prognosis

Treatment consists of broad-spectrum antibiotics and management of the underlying dysphagia.

Presentation of patients with talc granulomatosis can range from asymptomatic to fulminant disease [10]. It produces slowly progressive dyspnea on exertion (even after intravenous drug use has ceased), dry cough, nonspecific chest pain, and, occasionally, anorexia, weight loss, and mild fever. Lung sounds are usually normal. History of occupational exposure or of drug addiction is the major clue to the diagnosis.