Injection-Related Injuries in People Who Inject Drugs: Skin and Soft Tissue Infection, Vascular Damage, and Wounds

"Common SSTIs include cellulitis (Figure 1) and skin abscesses (Figure 2),⁵ and SSTI is common in PWIDs. In one needle exchange program (N = 152), 17.8% (n = 27) had an active abscess and 19.7% (n = 30) had a chronic wound.⁶ The upper extremities were the most common place for an abscess, and the lower extremities were most common for chronic wounds. In a study of active (injected in the past 30 days) PWIDs (N = 201) recruited in San Francisco between 2011 and 2013, Dahlman and colleagues⁷ noted the self-reported prevalence of lifetime SSTIs was about 70%. These infections can lead to serious morbidity and costly emergency room visits and hospitalizations. By assessing billing records through chart abstraction for 349 PWIDs in Florida, SSTIs were reported in 64% (n = 223); the total cost to the hospital for services rendered to treat injection drug use-related infections for a year was approximately $11.4 million.⁸ According to the Hospital Episode Statistics for England 1997–2016, about 6% (n = 63,671) of SSTIs and vascular infections are injection related.9 The most common causes were cutaneous abscess, phlebitis, and cellulitis. The number of injection-related admissions increased 33% per year from 1997 and 1998 through 2003 and 2004.⁹

"Two terms are important to aid in the understanding of SSTIs in PWIDs: skin popping and speedballing. Skin popping is extravasal (intramuscular or subcutaneous) injection into confined tissue compartments. When injected into a vascular space, drugs are quickly diluted. This dilution effect does not occur when drugs are injected into skin or muscle.¹⁰ Subcutaneous and intramuscular injections also bypass exposure to the bloodborne immunologic response, which may increase the risk of infection.¹¹

"Speedballing is injecting heroin in combination with a vasoconstrictor such as cocaine or methamphetamine. This decreases local blood flow to the injection site and exacerbates ischemia.11 The addition of crack cocaine to heroin is rationalized as providing a 'better high.'¹² The use of crack cocaine in speedballing has been associated with the deterioration of injection sites.¹² In general, speedballing is associated with an increased risk of infection.¹³"