HIV and Hepatitis are obvious risks of Injectable Drug Use, but are not discussed here.
(1) the drug is not sterile
: often "street" drugs are "cut" using fillers such as talc or other particulate matter which can readily be contaminated by fungal species.
(2) The drug has to be dissolved in H2O before injection
: If dissolved in water Pseudomonas can be a problem. If dissolved in saliva, oral organisms (not just bacteria, but also yeast and fungi in immuno-compromised patients).
(3) A needle is used
: considering the US and Ohio’s ridiculous policy of limiting access to clean needles, needles are frequently used multiple times and contrary to popular belief, only shared when there are no other options. The gradual dulling of the tip provides a safe haven for bacteria. The additional behavior of "cleaning" the needle with fingers or by licking it between uses sets up a pathway for oral Streptococi and Staph. aureus.
(4) The needle must traverse the skin
: in order to reach the subcutaneous tissue (skin popping) or vessels (IV) the needle must pass through the skin’s natural flora. The high frequency of Staph. aureus infections in IDUs suggests that it is their own naturally occurring flora that is gaining access to areas it shouldn’t be in.
Further complications
: many IDUs buy and use antibiotics on the street in an effort to prevent infections. This tends to increase the virulence profile and decrease anti-microbial susceptibility profile of colonizing microbes.
Local complications
– Complications at the site of injection
Infections of skin (Cellulitis)
Infection of subcutaneous tissue (abscesses, synergistic necrotizing faciitis)
Infections of the vessel wall (aneurysm formation, sometimes septic aneurysms)
Septic thrombophlebitis (infections on the internal aspect of the vessels)
Infections of underlying tissues (osteomyelitis, septic arthritis)
these complications may not be limited to the extremities; check everywhere because people inject everywhere. (really!)
Gram stains of aspirate, x-rays to rule out gas gangrene (subcutaneous air), surgery to clean out (I&D)
Systemic Complications
– seeding to a normally sterile site away from injection site
Endocarditis: especially right-sided endocarditis, tricuspid involvement in 50-75% of cases. Staph aureus most common in IDUs, Strep. viridans most common in non-IDUs.
all "shooting" patients presenting with fever are admitted and considered to have bacterial endocarditis until ruled out otherwise.
treatment consists of 5-6 wks of bacteriocidal antibiotics.
Septic emboli to the lungs: from the vegetations on the R-sided heart valves.
Septic emboli: bone and joints (particularly the spine and sternoclavicular joint), the spleen, the psoas muscle, the eye (particularly with Candida), and the epidural space.
Mycotic cerebral aneurysms: invasion of the vasa vasorum of blood vessels causes a weakening of the vessel wall and aneurysm formation. These aneurysms can bleed or burst leading to sudden or permanent neurologic damage.
Chronic Complications
Brawny edema – from lymphatic fibrosis and obstruction. This is seen in skin-poppers.
CHF – due to damaged heart valves
Pulmonary fibrosis – reaction to injected particulate matter (e.g. talc) in the drugs.
Arthritis / fused joints – from chronic bone and joint infections
Neurologic deficits – from septic emboli to the brain and seeping mycotic aneurysms.
Cirrhosis – not just from Hepatitis but also form R-sided cardiac failure