Management of Loeffler Syndrome with Intestinal Ascariasis
For Loeffler syndrome caused by Ascaris lumbricoides, treat with albendazole 400 mg twice daily for 3 days, and consider adding prednisolone 30 mg daily for 5 days in severe cases to reduce symptom duration. 1
Treatment Algorithm
First-Line Anthelmintic Therapy
Albendazole is the preferred agent for treating both the pulmonary (Loeffler syndrome) and intestinal phases of ascariasis:
- Albendazole 400 mg twice daily for 3 days is recommended during the acute pulmonary phase (Loeffler syndrome) 1
- After the acute phase resolves, albendazole 400 mg as a single dose effectively treats intestinal ascariasis 2, 1, 3
- Alternative single-dose regimens include mebendazole 500 mg once or ivermectin 200 μg/kg once 3
Corticosteroid Therapy for Severe Cases
- Prednisolone 30 mg daily for 5 days may reduce symptom duration in patients with severe respiratory symptoms (fever, significant cough, wheezing, hemoptysis) 1
- This is based on expert opinion and should be reserved for symptomatic relief in moderate-to-severe cases 1
Alternative Regimens
If albendazole alone is insufficient or you want broader empirical coverage (particularly if strongyloidiasis cannot be excluded):
- Albendazole 400 mg twice daily for 3 days PLUS ivermectin 200 μg/kg once daily for 3 days provides comprehensive coverage 1
- Mebendazole 100 mg twice daily for 3 days is an alternative to albendazole 1, 4
Critical Clinical Considerations
Timing of Treatment
- Loeffler syndrome occurs during the prepatent period (1-2 weeks post-infection) when larvae migrate through the lungs 1
- Stool microscopy may still be negative during this acute phase, so treatment should be empirical based on clinical presentation 1
- Repeat stool examination 3-4 weeks after initial symptoms to confirm intestinal infection and treatment success 3
Important Caveats
Do NOT use corticosteroids if strongyloidiasis is suspected, as steroids can precipitate life-threatening hyperinfection syndrome with Strongyloides stercoralis 1. Key distinguishing features:
- Strongyloides causes larva currens (rapidly migrating urticarial tracks) which Ascaris does not 2
- If there is any doubt about the causative organism, add ivermectin to the regimen rather than using steroids alone 1
- Strongyloides requires more aggressive treatment: ivermectin 200 μg/kg on days 1,2,15, and 16 in immunocompromised patients 1
Diagnostic Confirmation
While treatment is often empirical during acute Loeffler syndrome:
- Concentrated stool microscopy remains the gold standard once the intestinal phase begins 2, 3
- Look for migratory pulmonary infiltrates on chest X-ray and peripheral eosinophilia to support the diagnosis 1, 5
- Rarely, larvae may be visible in sputum or bronchoalveolar lavage during the pulmonary phase 1, 5
- Adult worms passed in stool (earthworm-sized, white/pink) confirm ascariasis 2, 3
Expected Outcomes
- Cure rates exceed 95% with appropriate anthelmintic therapy 6
- Respiratory symptoms typically resolve within days to weeks with treatment 7
- Radiographic infiltrates should resolve within 1 month of treatment 8
- No special procedures (fasting, purging) are required 4