Loffler's syndrome (simple pulmonary eosinophilia)

Introduction

Transient pulmonary infiltrates with eosinophilia.

Etiology

• helminth infection
  • schistosomiasis, trichinosis, filariasis, toxocariasis, Ascaris
• pharmaceutical agents
• idiopathic

Epidemiology

• travel to developing country
• rare & generally occurs in individuals previously exposed to Ascaris antigens

Pathology

• parasitic (helminths)
• migration of nematode larvae through the lungs where they mature in the alveolar capillary bed
• from there, they enter the alveoli & are carried by respiratory clearance mechanisms to the epiglottis where they are swallowed to regain access to the intestines
• arteritis may cause endocarditis, severe endocardial scarring, with negligible fibroelastosis

Clinical manifestations

• bilateral, diffuse, mottled pulmonary infiltrates
• mild bronchitis
  • dry cough
  • wheezing

Laboratory

• complete blood count
  • eosinophilia
  • anemia may be present
• serology for infectious agents
• stool for ova & parasites

Radiology

• chest X-ray: transient bilateral pulmonary infiltrates

Complications

• Loffler's endocarditis commonly with thromboembolism, including embolic stroke

Differential diagnosis

• tuberculosis:
  • radiographic pulmonary infiltrates are not transient
  • eosinophilia not common

Notes

• distinguish from Lofgren's syndrome

More general terms

• pulmonary infiltrates with eosinophilia (PIE) syndrome

Additional terms

• helminth infection
• Lofgren's syndrome