Discussion:
Intravenous drug users may experience needle breaking incidences during their self-injection. (5) The time taken for needles to migrate from soft tissues and embolize centrally can vary from a matter of a few hours to several days (6). Needle embolization to the lung is rarely reported in intravenous drug abusers, and most of the reported cases of needle embolization were iatrogenic embolization after the vascular intervention.
Richardson and colleagues performed a literature review of over 200 patients who had embolization of catheter fragments. They identified embolization to the lung periphery in eight cases; none of them required treatment. (7)
Needle breaking is common in intravenous drug users, but under-reported. In a survey among intravenous drug users, one-fifth of participants reported a needle breaking during drug injection, many of which could not be surgically or individually recovered. (5) Among eight patients of pulmonary needle embolism, Hart and co-workers reported seven cases with right lung embolization (8). In agreement with most of the reported embolization to the lung, our patient had embolization to the right lung.
Needle embolization to the heart was associated with pericarditis, endocarditis, and pulmonary abscess (9). However, most cases of needle embolization to the lung were not associated with complications. One patient with needle embolization to the lung presented with organized pneumonia with staph aureus (1).
Because of the stigmata of drug abuse, patients with broken needles may be reluctant to seek medical advice. Patients may present later with pulmonary complications such as infection or pneumothorax, and prior awareness of this condition could lead to the diagnosis of the cause. Migration of foreign bodies outside the lung has been previously reported (10), and needle embolization should be suspected in all pulmonary foreign bodies.
There is no standard medical management for pulmonary needle embolism reported in the literature. We discharged the patient on low dose Aspirin for fear of thrombosis on top of the foreign body. The role of antiplatelet medications in these cases is not known, and there are no recommendations against or with the use of them in needle pulmonary embolization. The patient remained symptom-free, and no complications were reported after six months of follow-up.