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Sudden-Onset Acute Obsessive-Compulsive Disorder Associated with Streptococcus and Brain MRI Hyperintensity in a

Joan Jory¹, Kenneth Handelman²

¹Department of Family Relations and Applied Nutrition, University of Guelph, Guelph, ON L8N 3K7, Canada.

Healthcare (Basel, Switzerland)

|January 23, 2024

Insights

This case study suggests streptococcal infections may trigger sudden-onset obsessive-compulsive disorder (OCD) in young adults. Early antibiotic treatment for strep infections could improve OCD outcomes.

Area of Science:

Neuroscience
Infectious Disease
Psychiatry

Background:

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS) are recognized in children.
Evidence linking streptococcal infections to sudden-onset Obsessive-Compulsive Disorder (OCD) in young adults is limited.
Delayed diagnosis and treatment of strep infections can worsen clinical outcomes.

Observation:

A 24-year-old presented with acute, sudden-onset OCD, unresponsive to conventional treatments for three years.
A brain MRI revealed a new temporal lobe hyperintensity coinciding with OCD onset.
Elevated antistreptolysin-O (ASO) titers were detected at age 27, prompting antibiotic intervention.

Findings:

Antibiotic treatment (Amoxicillin, then Amoxicillin + Clavulanate) led to improved OCD symptoms and treatment response.
Neuroinflammation, indicated by temporal lobe hyperintensity, persisted during the observation period.
ASO titers initially rose with Amoxicillin before normalizing with combination therapy.

Implications:

This case suggests a strong association between streptococcal infection, neuroinflammation, and sudden-onset OCD in young adults.
Earlier identification and antibiotic treatment for strep infections may enhance OCD remission rates.
Increased clinical awareness for early strep and ASO assessment in young adults with sudden-onset OCD is warranted.

Read full analysis

Abstract

Background:

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal (strep) infections (PANDAS) are a recognized medical entity among children. But evidence for strep-mediated sudden-onset obsessive-compulsive disorder (OCD) in young adults is very limited. Delayed strep assessment and treatment may negatively impact clinical outcomes.

Methods:

We describe a young adult with acute sudden-onset OCD (age 24), treated unsuccessfully with medication and therapy for 3 years. At age 27, antistreptolysin-O (ASO) was tested, based on extensive pediatric history of strep infections. Antibiotic treatment was initiated.

Results:

Magnetic resonance imaging (MRI) identified a new temporal lobe hyperintensity at OCD onset (age 24), which persisted at ages 25 and 30. ASO titers were elevated from age 27 through 29. Following Amoxicillin treatment, ASO initially increased. Subsequent Amoxicillin + Clavulin treatment produced improved OCD symptoms and treatment response, with no adverse effects.

Conclusion:

These results strongly suggest an association among strep infection, neuro-inflammation and sudden-onset OCD in this young adult whose response to medication and therapy was successful only after high-dose antibiotic intervention. Greater OCD remission potential may be possible with earlier identification and antibiotic treatment than 3 years post OCD onset. These findings add to the limited literature on strep as an etiology of the sudden-onset of OCD in young adults. They also lend urgency to increased frontline awareness for early strep and ASO assessment in sudden-onset acute OCD among young adults.

Keywords:

MRI OCD adult antistreptolysin strep streptococcus

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