Hard metal lung disease: a case series

Abstract

Objective:To describe diagnostic and treatment aspects of hard metal lung disease (HMLD) and to review the current literature on the topic. Methods:This was a retrospective study based on the medical records of patients treated at the Occupational Respiratory Diseases Clinic of the Instituto do Coração, in the city of São Paulo, Brazil, between 2010 and 2013. Results:Of 320 patients treated during the study period, 5 (1.56%) were diagnosed with HMLD. All of those 5 patients were male (mean age, 42.0 ± 13.6 years; mean duration of exposure to hard metals, 11.4 ± 8.0 years). Occupational histories were taken, after which the patients underwent clinical evaluation, chest HRCT, pulmonary function tests, bronchoscopy, BAL, and lung biopsy. Restrictive lung disease was found in all subjects. The most common chest HRCT finding was ground glass opacities (in 80%). In 4 patients, BALF revealed multinucleated giant cells. In 3 patients, lung biopsy revealed giant cell interstitial pneumonia. One patient was diagnosed with desquamative interstitial pneumonia associated with cellular bronchiolitis, and another was diagnosed with a hypersensitivity pneumonitis pattern. All patients were withdrawn from exposure and treated with corticosteroid. Clinical improvement occurred in 2 patients, whereas the disease progressed in 3. Conclusions:Although HMLD is a rare entity, it should always be included in the differential diagnosis of respiratory dysfunction in workers with a high occupational risk of exposure to hard metal particles. A relevant history (clinical and occupational) accompanied by chest HRCT and BAL findings suggestive of the disease might be sufficient for the diagnosis.

Evaluation of exposures and respiratory health concerns in a paper converting equipment manufacturing facility.

“…Various processes at this facility had the potential to generate airborne exposures to metal and silica particles and one employee had such particles demonstrated in his lung tissue. However, the disease encountered here is not pathologically or radiologically consistent with hard metal lung disease [Mizutani et al 2016] or silicosis [Leung et al 2012].…”

Hard Metal Lung Disease with Favorable Response to Corticosteroid Treatment: A Case Report and Literature Review

“…Co, cobalt; Fe, iron; K, potassium; Ni, nickel; Se, selenium; TBLB, transbronchial lung biopsy; Ti, titanium; W, tungsten. patients with HMLD are expected to show favorable response to corticosteroid treatment, although one patient died due to an aggravation of HMLD (Mizutani et al 2016).…”

“…Among the 18 patients, six cases, including our patient, were treated with corticosteroids (Yokota et al 1996;Enriquez et al 2007;Bezerra et al 2009;Kim et al 2013;Nakamura et al 2014), because the symptoms and/or radiological findings did not show improvement even after avoiding dust exposure before corticosteroid therapy. However, the detailed information of remaining 12 cases were unknown (Schwarz et al 1994;Dunlop et al 2005;Sakamoto et al 2008;Moreira et al 2010;Kaneko et al 2010;Sakai et al 2010;Nureki et al 2013;Mizutani et al 2016). On the other hand, Huang et al (2012) reported that proper prevention of dust exposure (change of workplace, proper wearing of mask, maintenance of better exhaust ventilation and air condition monitoring in the workplace) was effective in patients with HMLD.…”

“…The radiological and pathological characteristics of HMLD partially resemble HP (Coates and Watson 1971;Gotway et al 2002;Tanaka et al 2014;Mizutani et al 2016), and giant cell interstitial pneumonia (GIP), multinucleated giant cells in the airspaces with interstitial pneumonia with centrilobular fibrosis, is the common pathological finding; however, other pathological fibrotic patterns, such as the usual interstitial pneumonia (UIP) pattern, can also be seen (Ohori et al 1989;Akira 1995;Moriyama et al 2007;Tanaka et al 2014). The pathological patterns of HMLD consist of both GIP and UIP, and the UIP pattern is thought to be a prominent feature in advanced cases of the disease.…”

“…The main components of hard metals are tungsten carbide and cobalt, with small quantities of other materials, such as chromium, nickel, titanium, and tantalum, also present in varying degrees. Because of their extreme hardness, hard metals are widely used for cutting and sharpening metals, drilling wells, polishing diamonds, and dental prostheses (Mizutani et al 2016). The diagnosis of HMLD is essentially given by occupational exposure history to hard met-als, the clinical, radiological, and pathological findings of interstitial lung diseases, although the diagnostic criteria of HMLD used in each report show some differences (Coates and Watson 1971;Tanaka et al 2014).…”