[Featured Image: Creative Commons, danielleellis55 on Flickr.]
First off here’s a video I recorded for the CEM FOAMed network on “approach to the injecting drug user“. Be sure to subscribe on iTunes and check out the site. There’s a podcast feed and a blog feed, so be sure to get both.
httpv://vimeo.com/98215239
[Direct Download ]]
Injecting Drug User (IDUs) are frequent attenders at EDs for lots of reasons. While there is no doubt that there are a lot of social factors involved in these attendances, we can all too easily forget that these patients get really sick and often get left in the bottom of the queue of patients waiting to be seen. I think “the approach to the IDU” would make a great chapter for Rosen’s but it’s not in there yet. Harwood Nuss is the only one I’ve seen with a good chapter on it.
Complications of injection drug use
Hardwood-Nuss 5th edition p1398
I find this population of patients perhaps the most fascinating to treat. Generally ostracised by society in the way homeless people usually are. Usually undertriaged at the front door (“just another junkie”) I frequently find them in the waiting room with fairly dramatic vital signs. Without doubt injection drug use is usually not compatible with a stable and productive lifestyle and low grade criminality abounds. Certain aspects of the doctor patient relationship can be challenging here but they aren’t always drug seeking the way we expect they are.
And if your waiting room is anything like mine by the time they’ve waited 12 hrs to be seen then they’ve usually gone into withdrawal and it’s easy to blame all their symptoms and abnormal vital signs on withdrawal (even though their symptoms and abnormal vital signs all occurred prior to their withdrawal…)
All this to say that we approach them with so many cognitive biases and good old fashioned prejudices that it’s no wonder we fail to diagnose lots of the really interesting illnesses they bring with them.
Soft tissue infections
- Probably higher incidence of MRSA
- Most tentanus and wound botulism these days is associated with IDU
- Necrotising fascitis is a much higher risk
- Pyomyositis is a nice complication
Vascular
- DVT
- Arteriovenous malformations
- Pseudo aneurysm
- Here’s a quote “any mass over a vascular territory may actually be a pseudo aneurysm and should be approached with caution”
- I know a number of people with great stories of enthusiastic junior surgeons incising and draining these with impressive and unexpected results
- Associated abscess
- All 4 of the above in the same leg as I saw once…
- Those lovely cutaneous groin sinuses that descend to dear knows where.
- Mycotic aneurysms, typically with infectious endocarditis
Pulmonary
- ‘Pocket shooting’: injecting into the supraclvaicular space in the hope of finding a vessel. Can result in pneumo, haemo, hydropneumo and the wonderfully titled pyopneumothorax
- Dissolving tablets and injecting them can result in what I’ve heard called trash lung or talc lung. [Check out BroomeDocs podcast with @dreapadoirtas on this]
- This can cause granulomas in the pulmonary and even retinal vasculature (in fact looking at the retinas for talc might be better CXR or pulmonary function tests)
- Restrictive and obstructive dysfunction can occur. I suspect this is commoner than we suspect. I see a lot of IDUs with lowish sats and it gets blamed on something like COPD from smoking.
- Chronic pulmonary hypertension can result
Skeletal
- Osteomyelitis and septic arthritis can be local or haematogenous
- Commonest is vertebral osteomyelitis usually lumbar which may have associated disc it is with or without the even more emergent spinal epidural abscess
- Pain is often chronic (as has been in the cases I have seen)
- Don’t expect fever (unless you’re the admitting doctor in which case it can’t possibly be vertebral osteo without a fever…)
- Joint involvement is axial. Think sacroiliac, sternoclavicular, hip and pubic symphysis. (Mainly fibro cartilaginous joints if you’re into the anatomy of it all)
- This is really important as no one will consider septic arthritis in someone with tender central chest pain.
Central nervous system
- Meningitis both fungal and bacterial
- Various sites for epidural abscesses
- Brain abscesses
- CNS aspergillosis
- Cerebral murcomycosis (even when HIV negative)
- Headache, fever, cranial and motor deficits
- Apparently basal ganglia lesions on CT are the key
Fungal endophthalmitis
- Decreased acuity, eye pain
- White vitreal exudate on fundoscopy
Blood Born Viruses
- Hep C (almost ubiquitous amongst IDU. >80% in our population)
- Hep B (up to 80% become seropositive over lifetime)
- HIV (about 10% in our local population)
Endocarditis
- (lifetime incidence of 5%)
- Classic signs are rare
- Mainly right sided
Cotton fever
- A brief, febrile episode following injection when the solution is filtered through cotton balls
- No way to distinguish this in the ED from the other more serious occult causes of fever in the IDU
It might be easier is to think about common clinical presentations and then apply appropriate IDU pathologies
IDU with stroke
- Brain abscess
- Subdural empyema
- Botulism
- Mycotic aneurysms
- Good old fashioned stroke
Groin pain
- Abscess
- AV fistula
- DVT
- Pseudo aneurysm
- And I suppose it could be just a hernia
Chest pain
- Pneumonia
- PE (esp in groin injectors)
- ACS (chronic inflammatory states like HIV lead to accelerated atherosclerosis. Never mind the cocaine use)
- Sternal joint osteomyelitis
Headache
- Brain abscess
- Meningitis
- SAH (remember all the cocaine use that goes with the heroin)
- Complications of associated HIV
- Toxoplasmosis
- Lymphoma
- And yes it could just be a migraine too i suppose…
Back pain
- Epidural abscess
- Discitis
- Vertebral osteomyelitis
- And yes it could just be good old fashioned back pain too I suppose
Fever
- Endocarditis
- Meningitis
- Osteomyelitis
- Cotton fever
- HIV related
- TB (a lot of these guys are homeless and in Dublin anyhow there are reasonably high rates of TB amongst the homeless)
- Haematological malignancy
- And yes I suppose it could just be a flu or the dreaded ‘viral illness’
Shortness of breath
- PE
- Talcosis or trash lung
- Chronic pulmonary hypertension
- Pneumothorax from trying to inject a neck vein
- Aspiration from their recent OD, GCS 3 episode
- And yes I suppose it could be a good old fashioned chest infection too
Cellulitis in IDU
- necrotising fasciitis
- Pyomyositis
- Subcutaneous abscess
- And yes I suppose it could be a simple staph or strep cellulitis
References/FOAMed Resources:
- Nice EM News Post on the febrile IDU
- Hardwood-Nuss 5th edition p1398
- A paper from our place characterising our population