Lead arthropathy and systemic lead poisoning from an intraarticular bullet.

55-year-old man presented to the department of neurology with muscle wasting. Initially hyperreflexic, he later became markedly hyporeflexic and developed signs of peripheral neuropathy. Over the course of approximately 3 months, various diagnoses were entertained. An extensive workup revealed that he was profoundly anemic, despite normal iron studies. On the basis of results of a bone marrow aspiration, lead poisoning was considered. His serum lead level was 198 µg/dL (normal range, 0‐30 µg/dL), indicating chronic lead poisoning. The only identifiable source for this elevated serum lead level was a retained bullet in the patient’s left hip, from a gunshot wound 15 years earlier. Hip radiographs obtained at the time of injury (Fig. 1A) showed a deformed bullet lodged in the hip joint. Later studies revealed fragmentation of the bullet, with distribution of fragments throughout the hip joint, and associated severe osteoarthritis (Fig. 1B). The patient was started on chelation therapy, and left-hip synovectomy and hemiarthroplasty were performed. The patient’s serum lead level dropped to normal range within 2 weeks. Patients with gunshot wounds often have retained bullet fragments. In most cases, lead fragments in soft tissues become encapsulated by fibrous tissue, and are effectively inert. This is not the case when bullet fragments are in contact with synovial fluid. Intra-articular lead fragments are a well-recognized cause of lead synovitis and arthritis, as well as systemic plumbism. Lead poisoning from intraarticular bullets has been recognized since 1867 [1]. Mechanical forces within the joint pulverize the bullet and distribute the lead fragments. These lead fragments interact with the acidic synovial fluid, producing foreignbody reactions, mechanical articular cartilage damage, proliferative synovitis, and destructive arthritis. The inflamed synovial membrane favors absorption of lead into the systemic circulation [2]. The fragmentation and migration of bullet fragments throughout the joint are well depicted on serial radiographs (Fig. 1). The articular cartilage thins and may become visible because of the deposition of lead particles, with an appearance resembling chondrocalcinosis. The inner surface of the synovium may become similarly opacified by fine lead particles [3‐5]. Ultimately, the entire joint capsule and cartilage may become outlined, resulting in a “lead arthrogram” or “plumbogram” (Fig. 1B). Lead arthropathy and systemic plumbism from retained bullet fragments usually present years or decades after the patient was shot. Because the symptoms may be vague and intermittent, and the treating physician may be unaware of the gunshot injury, diagnosis may be delayed. The radiographic identification of intraarticular bullet fragments should prompt an urgent orthopedic consultation. The timely removal of lead particles and debridement of bone and cartilage fragments will prevent both lead arthropathy and toxicity [4]. If lead arthropathy is identified,