Risk Factors for Skin and Soft‐Tissue Abscesses among Injection Drug Users: A Case‐Control Study

Abstract

Skin and soft-tissue abscesses, a common problem among injection drug users (IDUs), result in serious morbidity for the patient and costly hospitalizations for incision and drainage; however, there has been little etiologic or preventive epidemiologic research on this problem. We performed a case-control study that enrolled 151 IDUs who had been given a new diagnosis of abscess requiring incision and drainage (cases) and 267 IDUs who did not have abscess or other bacterial infection during the previous year and who were stratum-matched to cases according to age, sex, and race (controls). Subcutaneous or intramuscular, instead of intravenous, injection is a major risk factor for abscess among IDUs. The injection of a cocaine and heroin mixture, or "speedball," may predispose patients to develop abscess by inducing soft-tissue ischemia. Cleaning the skin with alcohol before injection was found to have a protective effect. Neither human immunodeficiency virus nor human T-lymphotropic virus type II seropositivity was significantly associated with abscess.

The extent of injection site infection in injecting drug users: findings from a national surveillance study

“…Women were more likely to report an injection site infection, and this has also been found in other studies [7,8,11,15]. This could reflect a greater awareness of infections, and/or a greater vulnerability to injection site infections in female injectors [14].…”

“…The current study found that frequent injection, the use of certain injection sites (hand, groin, legs), and the reuse of injecting paraphernalia were all associated with reporting symptoms of injection site infections during the last year. Previous studies have found similar associations [8,11,12,14,15], and also associations with inadequate washing of hands or cleaning of the injection sites [6,11,12], and the use of multiple injection sites [11,12]. The associations with particular injection sites needs further examination, but may reflect some of these sites being more difficult to keep clean or the need to use certain sites due to others becoming unusable due to vascular damage, injury, or infection.…”

“…Studies elsewhere have found similar associations with poor housing and homelessness [3,4,13]. Homelessness is possibly an indicator of increased rates of injection in public or semi-public environments, which has been related to poor injection hygiene [11,12].…”

“…Injection site infections have been associated with poor hygiene and unsafe injection practices including: inadequate cleaning of the hands or the injection sites [11][12][13]; needle and syringe re-use [8,11] ; frequent injection [8,[14][15][16] ; subcutaneous injection [6,11] ; the injection sites used [8,13,16]; the drugs injected [8,11,14,15] ; and drawing blood back into the syringe repeatedly [9]. Higher levels of these infections have also been reported to be associated with environmental factors, including poor housing and homelessness [3,4,13], and with gender [3,4,8,14] and source of income [4].…”

Microbiology of Bone and Joint Infections in Injecting Drug Abusers

“…Soft tissue infections at the injection site have been well studied in large series of patients [1,8,9,16,19,21], including up to 855 patients [1]. We identified ten clinical series specifically reporting on patients with IDA and infections of the bone and joint [2, 4-7, 11, 13-15, 18].…”