Management of Eosinophilia in HIV-Infected Patients
In HIV-infected patients with eosinophilia, the primary approach should focus on ruling out helminth co-infection, which is a more likely cause than HIV itself, especially in returning travelers or migrants from endemic regions. 1
Diagnostic Approach
Initial Evaluation
- Complete blood count with differential to confirm and quantify eosinophilia
- HIV viral load and CD4 count assessment
- Comprehensive travel history, focusing on regions endemic for helminth infections
- Medication review (especially NSAIDs, beta-lactams)
- Assessment for cutaneous manifestations (particularly important in HIV patients)
First-Line Investigations
Parasitic workup:
- Concentrated stool microscopy for ova and parasites (3 samples)
- Strongyloides serology (high priority due to risk of hyperinfection in immunocompromised patients) 1
- Schistosomiasis serology (if travel to endemic areas)
- Filarial serology (if appropriate travel history)
Skin evaluation:
- Skin examination for rash, pruritus, follicular papules
- Skin biopsy if suspicious lesions present (particularly for eosinophilic folliculitis)
Additional testing based on symptoms:
- Cerebrospinal fluid analysis if neurological symptoms (to rule out eosinophilic meningitis) 2
- Chest imaging if respiratory symptoms
Common Causes of Eosinophilia in HIV Patients
Infectious Causes
- Helminth infections (highest priority to exclude):
- Strongyloidiasis (risk of hyperinfection syndrome in immunocompromised)
- Schistosomiasis
- Filariasis
- Hookworm and other soil-transmitted helminths
HIV-Associated Dermatologic Conditions
- Eosinophilic folliculitis - particularly common in advanced HIV disease (CD4 <250 cells/mm³) 3
- Prurigo nodularis
- Atopic dermatitis
Other Causes
- Medication reactions
- Opportunistic infections with fungal pathogens (e.g., Cryptococcus)
- IRIS (Immune Reconstitution Inflammatory Syndrome) after starting ART
Management Algorithm
1. If Helminth Infection Identified:
- Treat according to specific pathogen guidelines:
2. If Eosinophilic Folliculitis Identified:
- First-line: Potent topical corticosteroids 5
- Second-line: Topical tacrolimus 5
- For severe cases: UVB phototherapy (considered "gold standard" for HIV-associated eosinophilic folliculitis) 5
- Alternative options:
- Antihistamines (cetirizine 20-40 mg/day)
- Itraconazole (200-400 mg/day)
- Metronidazole (250 mg three times daily)
3. If No Cause Identified and Persistent Eosinophilia:
- Consider empiric treatment with albendazole 400 mg plus ivermectin 200 μg/kg for possible undetected helminth infection 1
- Optimize antiretroviral therapy (ART) - improvement may occur with immune reconstitution
- Hematology referral if eosinophilia persists at ≥1.5 × 10⁹/L for >3 months 6
Special Considerations
Monitoring
- Follow-up eosinophil counts after treatment
- Repeat stool examinations to document clearance of helminth infections
- Monitor for end-organ damage with persistent eosinophilia
Cautions
- Avoid extensive workup for asymptomatic eosinophilia in HIV patients with cutaneous disease - this is often not warranted 7
- Screen for Loa loa before administering ivermectin in patients with travel to West or Central Africa due to risk of severe reactions 1, 4
- Consider drug interactions between antiretroviral medications and treatments for eosinophilia
Key Pitfalls to Avoid
- Failing to consider helminth co-infection as the primary cause of eosinophilia in HIV patients
- Missing eosinophilic folliculitis, which can be an important marker of advanced HIV disease
- Overlooking medication causes of eosinophilia
- Inadequate follow-up after treatment
- Not recognizing that eosinophilia in HIV patients is most commonly associated with cutaneous manifestations rather than other conditions typically associated with eosinophilia