What is the appropriate management for a male in his 20s with eosinophilia and pruritic (itching) skin lesions?

Management of Eosinophilia with Pruritic Skin Lesions in a Young Male

For a male in his 20s presenting with eosinophilia and itching skin lesions, empirical treatment with albendazole 400 mg single dose plus ivermectin 200 μg/kg single dose should be initiated after obtaining travel history and basic diagnostic workup, as helminth infections are the most common infectious cause of this presentation. 1

Initial Diagnostic Approach

Essential History Elements

• Travel or residence history to tropical/subtropical regions, particularly focusing on exposure to endemic areas for helminth infections 2
• Specific exposures: freshwater contact (schistosomiasis), walking barefoot on soil/sand (hookworm, strongyloides), consumption of raw/undercooked fish or meat (anisakiasis, trichinosis), and insect bites 2
• Skin lesion characteristics: migratory patterns (cutaneous larva migrans moves 1-2 cm/day, larva currens moves 5-10 cm/hour), distribution (trunk/buttocks suggests strongyloides, legs/buttocks suggests onchocerciasis), and presence of nodules 2

First-Line Investigations

• Complete blood count to quantify eosinophilia level 1
• Concentrated stool microscopy and/or fecal PCR for parasites (three samples on separate days) 2
• Serology for helminth infections including strongyloides, schistosomiasis, and filariasis (only if West Africa travel history) 2
• Skin snip examination if onchocerciasis suspected based on travel to endemic river areas 2

Treatment Strategy

Empirical Antiparasitic Therapy

If initial workup is negative but travel history to endemic regions exists, treat empirically with albendazole 400 mg single dose plus ivermectin 200 μg/kg single dose. 1 This combination targets the most common helminth infections causing eosinophilia with skin manifestations 2.

Specific Pathogen-Directed Treatment

For Strongyloidiasis (Larva Currens Pattern)

• Ivermectin 200 μg/kg once daily for 2 days is first-line treatment 2
• Repeat treatment may be required; verify eradication with follow-up stool studies 2
• This is critical as strongyloides can cause hyperinfection syndrome in immunocompromised states 2

For Cutaneous Larva Migrans (Serpiginous Rash)

• Ivermectin 200 μg/kg single dose OR albendazole 400 mg once daily for 3 days 2
• Clinical diagnosis is sufficient; this condition is self-limiting but treatment accelerates resolution 2

For Onchocerciasis (Severe Pruritus with Nodules)

• Critical warning: Exclude loiasis before treatment if West Africa exposure 2
• Doxycycline 200 mg once daily for 6 weeks to target Wolbachia bacteria, starting on day one 2
• Ivermectin 200 μg/kg monthly for 3 months, then every 3-6 months until asymptomatic 2
• Urgent ophthalmology assessment required due to risk of blindness 2

For Schistosomiasis (Urticarial Rash, Freshwater Exposure)

• Praziquantel 40 mg/kg twice daily for 1-2 days depending on species 2
• Repeat treatment after 4-6 weeks may be necessary 2

For Hookworm Infection (Ground Itch)

• Albendazole 400 mg once daily for 3 days 2
• Severe disease may require prednisolone 40-60 mg once daily 2

Symptomatic Management

Pruritus Control

• Topical emollients and mild-to-moderate potency corticosteroids for localized lesions 1
• Oral antihistamines (first or second generation) for generalized pruritus 1
• Gabapentin, pregabalin, or mirtazapine for severe refractory pruritus 1
• UVB phototherapy may be effective for persistent cases 1

Critical Pitfalls and Warnings

Diethylcarbamazine (DEC) Caution

Never use DEC without excluding onchocerciasis co-infection, as it can cause severe reactions including blindness, particularly in patients with travel to co-endemic regions 2. Skin snips and slit lamp examination are mandatory before DEC use 2.

Loiasis Screening

For patients with West Africa travel history and suspected filariasis, check microfilarial load before treatment. High levels (>1000/ml) require corticosteroid pretreatment with albendazole to reduce microfilariae before definitive therapy, as DEC can cause fatal encephalopathy 2.

Non-Infectious Causes

If helminth workup is negative and empirical treatment fails, consider:

• Allergic/atopic conditions (asthma, eczema, drug reactions) - most common non-infectious causes 2
• Hypereosinophilic syndrome if eosinophilia ≥1.5 × 10⁹/L persists >3 months - requires hematology referral 2
• Eosinophilic pustular folliculitis - may require indomethacin 75 mg/day 3
• Systemic vasculitis or malignancy - rare but serious causes requiring specialist evaluation 2, 4

Follow-Up Strategy

• Repeat eosinophil count 4-6 weeks post-treatment to assess response 2
• Repeat stool studies if strongyloidiasis treated to confirm eradication 2
• Refer to hematology if eosinophilia persists ≥3 months despite treatment of infectious causes 2
• Monitor for end-organ damage (cardiac, pulmonary, neurologic) in persistent severe eosinophilia 2