Table 1.

Literature review.

No. of patients	Age (yr)	Sex	Occupation	Tissue sample	Reference	Location (country)	Histology	Elemental analysis	Corticosteroids (Y/N/NA)	Prognosis
1	31	M	Welder in the aircraft industry for 5 years	Open lung biopsy	Chen et al. (1)	USA	Diffuse pulmonary granulomatosis	Aluminum	NA	NA
2	32	M	Chemist in a catalyst fabrication plant for 8 years	TBLB	De Vuyst et al. (10)	Belgium	Sarcoid-like epithelioid granulomas with Langhans-type giant cells	Aluminum, iron, silicon, aluminosilicates, rare nickel, tin, chromium, and titanium	N	16 months later, chest radiograph and lung function show no significant changes
3	37	M	Dental laboratory technician for 20 years	VATS biopsy	Brancaleone et al. (11)	Belgium	Non-caseating epitheloid granulomas	Aluminum, silicon, silicates, beryllium	Inhaled corticosteroid	2 years later, exertional dyspnea and a little cough persist. Lung function and arterial blood gas remain unchanged
4	50	F	A worker in a metal reclamation factory for 15 years	Open lung biopsy	Cai et al. (12)	China	Non-necrotizing granulomas with multinucleated giant cells	Aluminum	Oral corticosteroid	Clinical, functional, and radiological improvement
5	64	F	To polish wood furniture with sandpaper and wire brush without protection for 40 years	Lymph node biopsy	Catinon et al. (13)	France	Non-necrotizing granulomas with epithelioid cells and multinucleated giant cells	Aluminum; silicates; steel (iron, chromium, and nickel); silica; iron; calcite; titanium	NA	NA
6	33	M	A worker in the battery manufacturing industry for 7 years	VATS biopsy	Tomioka et al. (14)	Japan	Epithelioid cell granuloma	Aluminum; silicon; iron; and titanium	N	4 years later, his VC is reduced by 12.5% and DLco is induced by 12.8%. His chest HRCT shows no changes
7	46	M	A worker in an aluminum-processing factory for 6 years	VATS biopsy	Tomioka et al. (14)	Japan	Epithelioid cell granuloma	Aluminum, silicon, iron, and titanium	N	6 years later, his chest HRCT shows no changes and no respiratory symptoms
8	44	M	To brush and polish surgical instruments without any protection for 7 years	VATS biopsy	Catinon et al. (15)	France	Granuloma with multinucleated giant cells	Aluminum, silicates, silicon, iron, steel, and titanium	NA	NA
9	59	M	A worker in a company that produced refractory material for 28 years	Lung biopsy	Baur et al. (16)	Germany	Necrotizing/focally infarcted granulomas and chronic lymphoplasmacytic inflammation	Aluminum, silicon, titanium, zirconium, niobium, vanadium, and steel	NA	NA
10	57	M	As a plumber exposed to asbestos, then a worker exposed to multiple metals (not detailed the exposure time)	VATS biopsy	Blin et al. (17)	France	DIP + non-necrotizing granulomas	Aluminum, zirconium, steel	Y	1-year evaluation: clinical, functional, and radiological improvement

Video-assisted thoracoscopic surgery (VATS) biopsy; TBLB, transbronchial lung biopsy; NA, not known or not done.