Candida Bloodstream Infections in People Who Inject Drugs: Denver, 2017–2018

Candidemia — a bloodstream infection with Candida yeasts — is usually thought of as a hospital infection. Its classic risk factors are a central venous catheter, intravenous feeding (total parenteral nutrition), broad-spectrum antibiotics, recent abdominal surgery, intensive care and long hospital stays. But as the opioid epidemic has driven up injection drug use, reports have linked it increasingly to candidemia, and to bloodstream infections with methicillin-resistant Staphylococcus aureus.

When the Colorado Department of Public Health and Environment (CDPHE) began tracking candidemia across the five-county Denver metropolitan area — 2.7 million people — in May 2017, as part of CDC's Emerging Infections Program, it found something unexpected within six months: about 1 in 10 cases were in people with a documented history of injecting drugs, and most of their positive blood cultures were drawn on the day they were admitted or soon after. CDPHE and CDC looked closer.

The numbers

Of 203 candidemia cases reported during 2017–2018, 23 (11%) were in 22 patients who had injected drugs in the previous year (one patient had it twice).

Where the infections started

So 14 of the 22 patients probably picked up Candida outside the hospital, likely from injecting. The median hospital stay for candidemia was 10 days (range 1–139).

How sick they were

• Seven (32%) had disseminated candidiasis damaging other organs: osteomyelitis (three), abscesses of the pelvis, psoas muscle and upper mediastinum (three), septic emboli (one) and endophthalmitis (one).
• Fifteen (68%) had another organism in a blood culture — most often Staphylococcus aureus — during that stay or in the six months before. In 10 (45%), another organism grew in the same culture as Candida: a sign that unsafe injection is probably common.

Drugs and injecting practices

In the six months before, medical records or urine tests showed opioids in 18 (82%), methamphetamine in 16 (73%), cannabinoids in 7 (32%), cocaine in 6 (27%), benzodiazepines in 4 (18%), and ecstasy (MDMA) and barbiturates in one each.

• Four (18%) reused old syringes, cotton or filters, or used dirty needles.
• Two (9%) had "cotton fever" — a fever that comes on fast right after injecting drugs filtered through cotton.
• Six (27%) were seen injecting, or trying to, while in hospital — illicit drugs or pain medicines not prescribed to them. Drugs and paraphernalia (syringes, spoons, lighters) were found in four of their rooms. Injecting drug use is a risk inside the hospital, not only outside it.

Missed chances

The patients had been to hospital or an emergency department three times on average in the six months before (range 0–10), mostly for drug dependence or withdrawal, pain, mental or behavioral disorders, and infections such as bacteremia, osteomyelitis and sepsis. Three had walked out against medical advice from an earlier visit.

What would help

The usual candidemia prevention — antibiotic stewardship, catheter care, antifungal prophylaxis — happens inside hospitals. People who inject drugs also need:

• education and resources to reduce injecting;
• safer injection — cleaning the injection site, using sterile water to prepare drugs, and never sharing equipment (CDC guidance);
• medication-assisted treatment for people injecting opioids;
• using every hospital and ED visit as a chance to intervene.

Unsafe injection also puts people at risk of bacterial infections, HIV, hepatitis B and hepatitis C.

Limits: the number of patients was small and from one area, and injecting — and details such as which drugs and how often — may have been missing from medical records.

Sources

Based on Devra M. Barter, Helen L. Johnston, Sabrina R. Williams, Sharon V. Tsay, Snigdha Vallabhaneni and Wendy M. Bamberg, "Candida Bloodstream Infections Among Persons Who Inject Drugs — Denver Metropolitan Area, Colorado, 2017–2018," MMWR, volume 68, Centers for Disease Control and Prevention; a work of the United States government in the public domain. The report gives the study's end as both August and September 2018, so only the years are given here; its "Candida lypolitica" is corrected to C. lipolytica.