II. Pathophysiology
- Predominately fresh water exposure
- Distribution
- Northern United States
- Canada
- Episodic outbreaks related to snail maturation
- Bright, warm days of summer induce snail shedding
- Most outbreaks occur near shore
- Distribution
- Inflammatory reaction to parasitic cercariae (larvae)
- Carriers: Snails
- Organisms
- Non-human schistosomes (parasitic flatworm)
- Flukes
- Mechanism
- Larvae penetrate Epidermis with water evaporation
- Larvae die once embedded
- Inflammatory reaction depends on sensitization
III. Symptoms and symptoms
- Areas affected limited to exposed areas
- Initial Pruritus from Acute Urticarial reaction
- Pruritus within 1 hour (minimal to intense)
- Later papular eruption occurs
IV. Differential Diagnosis
- Seabather's Eruption (limited to bathing suit area)
- Aquagenic Pruritus
V. Management: Symptomatic for Pruritus
- Antihistamines
- Cool compresses
- Sarna or Calamine lotion
- Low to medium potency Topical Corticosteroids
VI. Complications
- Secondary infection related to excoriation
VII. Prevention
- Dry Skin immediately after bathing
VIII. Course
- Lesions clear completely in 1 to 2 weeks
IX. References
- Habif (1996) Clinical Dermatology, 3rd ed, Mosby, 486
- Mulvihill (1990) Cutis 46:211-3 [PubMed]
- Pharis (1997) J Am Acad Dermatol 36:448-59 [PubMed]