Intravenous Drug Use May Lead to Chorioretinal Lesions

Heroin abuse. Ophthalmoscope view of the retina of the eye of a patient that has been damaged by chronic use of the drug heroin. The macula, where most of the eye’s light sensitive cells occur is seen dark-colored at center (with a red line pointing to it). The optic disc where nerves and blood vessel enter the eye is yellow at far right. Blood vessels are red. A small yellow patch at upper right of the macula is an area of light-sensitive cells which have been damaged by the heroin abuse. This kind of degeneration is called retinal maculopathy and can lead to damaged vision or blindness.
Even without visual symptoms, these patients were likely to have findings.

Even in the absence of optical symptoms, patients who have systemic infections related to intervenous drug use (IDU) may have chorioretinal lesions and other findings, according to a study published in Ophthalmology Retina.

Researchers conducted a hospital-based cross-sectional study to analyze the prevalence of vitreous and chorioretinal lesions, as well as to correlate symptoms with ophthalmic involvement in people who inject drugs (PWID). The study also involved characterizing the lesions and identifying their causative organisms.

The study’s results found vitreous or chorioretinal involvement in 16.7% of patients (n=16). Intraretinal or white-centered hemorrhage (IRH) was the most common finding, identified in 9 patients of 96, followed by chorioretinal infiltrate (n=8), endophthalmitis (n=5), and cotton wool spots (CWS, n=3). Among the patients with ocular involvement, 44% (7/16) were symptomatic, 5 of whom had endophthalmitis.

Participants of the study included 91 PWID with 96 unique hospitalizations for bloodstream infection (BSI) or related metastatic foci of infection (MFI). Participants were enrolled in the study from March 2018 to March 2020, and upon entry, they received a complete eye exam within 72 hours. Other data measured were sex, age, race, injection drug of choice (DOC), presence of co-infection with hepatitis B, hepatitis C or HIV, the pathogen causing systemic infection and type of infection, and history of prior infection related to IDU. 

The most common causative pathogen identified in patients with and without ocular findings was Staphylococcus aureus, and the researchers also found a correlation between the presence of ocular findings and ocular symptoms, worse visual acuity, and DOC of methamphetamine.

The researchers explain that ophthalmic findings were present in the absence of optical symptoms in more than 50% of participants, which is of note for this study. However, they emphasize that there was no change in clinical or ophthalmologic management upon identifying asymptomatic patients.

“This is likely because asymptomatic patients had either CWS, intraretinal hemorrhages, or metastatic infectious chorioretinitis without breakthrough into the vitreous cavity, and all patients in this study were already on intravenous antibiotics for their bloodstream infections at the time of their initial eye exam,” the study explains. 

Additionally, the study notes that its correlation of methamphetamine as a DOC with ocular findings as compared with other intravenous drugs such as heroin, cocaine, or synthetic opioids is contrary to previous studies, which correlated heroin with ocular findings. The researchers explain that this discrepancy may likely be due to a difference in DOC of the study’s participant base rather than a difference in true risk factor. 

Reference

Greven M, Weinstein J, Tsamis K, Vadala S, Barnes E, Peacock J. Vitreous and chorioretinal lesions in people who inject drugs hospitalized with bloodstream and related infections. Ophthalmol Retina. Published online March 3, 2021. doi:10.1016/ j.oret.2021.02.018.