What is the appropriate management for Ekbom syndrome (delusional infestation)?

Management of Ekbom Syndrome (Delusional Infestation)

Start treatment with antipsychotic medications as first-line therapy, with aripiprazole showing the highest complete remission rate at 79% among reported agents, though first-generation and second-generation antipsychotics demonstrate similar overall efficacy. 1

Initial Diagnostic Approach

Before labeling this as purely psychiatric, you must systematically exclude organic causes that can mimic or trigger delusional infestation 2:

• Check complete blood count and ferritin (threshold < 15–25 µg/L) to rule out iron deficiency, which frequently causes generalized pruritus that can manifest with delusional features 2
• Screen for systemic conditions including hepatic cholestasis, uraemia, malignancy, haematologic disorders, endocrine disease, diabetes mellitus, HIV infection, and sarcoidosis 2
• Evaluate for small-fiber neuropathy through detailed neurological examination looking for burning, paraesthesia, stinging, or tingling sensations; skin biopsy may be required as clinical findings can be subtle 2
• Obtain detailed exposure history including travel, sexual exposure, intravenous drug use, occupational hazards, and personal care products 2

Pharmacological Treatment Algorithm

First-Line: Antipsychotic Monotherapy

Second-generation antipsychotics are preferred due to tolerability, though efficacy is comparable to first-generation agents 1:

• Aripiprazole demonstrates the highest complete remission rate (79%) in available case series, making it the optimal initial choice 1
• Brexpiprazole may be substituted if aripiprazole causes intolerable akathisia or tremor, as it produces fewer extrapyramidal side effects while maintaining efficacy 3
• First-generation antipsychotics (complete remission 54.4%) and second-generation antipsychotics (complete remission 47.9%) show statistically similar effectiveness overall, with partial remission rates of 35% for both classes 1

Adjunctive Treatment for Comorbidities

• Selective serotonin reuptake inhibitors (SSRIs) achieve 79% complete remission and 43% partial remission specifically in patients with comorbid depression, anxiety, or trichotillomania 1
• Address underlying psychiatric disorders including depression, anxiety disorders, obsessive-compulsive disorder, and substance abuse, which commonly coexist with delusional infestation 2

Critical Management Principles

Therapeutic Alliance Challenges

• Patients typically refuse psychiatric referral and disengage from mental health services, requiring adapted communication strategies and sustained longitudinal engagement 4, 5
• Avoid confrontational approaches that directly challenge the delusional belief; instead, focus on symptom relief and functional improvement 5
• Multidisciplinary coordination between dermatology, infectious disease, and psychiatry is essential, as patients consult a median of three specialties (range 1-7) before diagnosis 6

Treatment Adherence Optimization

• Do not prescribe empirical antiparasitic treatment, as this reinforces the delusion; 10 of 20 patients in one series received inappropriate antiparasitic therapy, complicating subsequent psychiatric management 6
• Frame antipsychotic treatment in terms of reducing distress, improving skin healing, or addressing "nerve sensitivity" rather than treating "mental illness" 5
• Monitor closely for adherence, as patients frequently discontinue medications when they perceive the physician does not believe their infestation claims 5

Common Pitfalls to Avoid

• Never attribute symptoms solely to psychiatric causes without comprehensive medical workup; up to one-third of patients with chronic pruritus develop secondary anxiety or depression as consequences rather than primary causes 2
• Recognize that professional identity complicates treatment when patients work in healthcare or mental health fields, creating unique ethical conflicts and resistance to accepting psychiatric diagnosis 5
• Understand the pathophysiology involves dopaminergic imbalances and dopamine transporter system dysfunction, providing a neurobiological rationale for antipsychotic efficacy 7

Expected Outcomes

• Variable long-term prognosis: In one series, only 3 of 20 patients achieved complete resolution, 9 had persistent symptoms, and the remainder were lost to follow-up 6
• Sustained psychiatric engagement is achievable even in treatment-resistant cases through individualized longitudinal care and adapted therapeutic strategies 5
• Early intervention improves outcomes, as diagnostic delays from patients' resolute convictions lead to prolonged suffering and dermatological complications 7