Prevalence and Characteristics of Delusional Infestation in Individuals With Opiate Use Disorders Within One Health System: A Retrospective Cross-Sectional Study.

Objective: The recent development of xylazine adulteration of the illicit opiate supply has been associated with necrotic extremity wounds of unclear pathogenesis. This study sought to understand the prevalence and characteristics of delusional infestation (DI) among patients with opiate use disorders who also carried a diagnosis of cellulitis.

Methods: A retrospective cross-sectional study was performed in one health system to identify patients with opiate use disorder and cellulitis over the past three years who also described symptoms of DI. We collected demographics, comorbid substance use disorder, and psychiatric diseases and calculated the likelihood of association with drug use by applying the Naranjo Adverse Drug Reaction scale.

Results: Fifteen patients (3.2% of all opiate-dependent individuals) were identified as also having DI. All patients had recurrent symptoms of DI, persisting over 18.3 ± 16 months with 4.6 ± 2.3 different health system contacts. The mean age was 44.4 years (range: 25 to 63 years). Twelve were female (80%, chi-square 5.4, p = 0.02). All had open wounds. Psychiatric comorbidities were common, but only two were schizophrenic, and none were actively psychotic during contact with the health system. Symptoms were either definitely (n = 1) or probably (n = 14) associated with drug exposure, according to the Naranjo Adverse Drug Reaction scale. Thirteen (87%) were also abusing other stimulants. All workups were negative for parasites and eosinophilia.

Conclusions: The prevalence of DI in patients with opiate use disorder was identified as significantly higher than reported in other populations. The role of DI in the formation of skin wounds deserves further study.