What is Cercarial (Cerc) dermatitis?

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From the Research

Cercarial dermatitis, also known as swimmer's itch, is a skin condition caused by the penetration of the skin by larvae (cercariae) of schistosomatid flukes, and the most recent and highest quality study on this topic is from 2018 1.

Definition and Cause

Cercarial dermatitis is an allergic skin disease that occurs when the skin is infected by invasive stages (cercariae) of trematodes of the family Schistosomatidae. The symptoms of cercarial dermatitis are generally known, and the data on immune response in human patients are becoming more comprehensive 1.

Clinical Presentation

The onset of cercarial dermatitis is significantly faster, and the symptoms are heavier in participants with a history of the disease if compared to naive ones, who, however, also develop some of the symptoms 1. The symptoms include a diffuse eruption composed of prurigenous maculopapules that appears within 24 hours following exposure, and regression is spontaneous within one day to three weeks 2.

Prevention and Treatment

Prevention is advisable, and the optimal prevention for bathers is to swim in sufficiently deep water 2. Treatment is symptomatic in the majority of patients, and emollients and topical corticosteroids are effective for most patients 3, 4.

Diagnosis

The diagnosis of cercarial dermatitis can be improved by a complex approach, including differential cell counts, dynamics of selected cytokines, and dynamics and quality of antibody response 1. However, no antigen with a universal diagnostic potential was confirmed, and individual immunoblot patterns of IgG response should be interpreted carefully 1.

Key Points

  • Cercarial dermatitis is an allergic skin disease caused by the penetration of the skin by larvae (cercariae) of schistosomatid flukes.
  • The symptoms include a diffuse eruption composed of prurigenous maculopapules that appears within 24 hours following exposure.
  • Prevention is advisable, and the optimal prevention for bathers is to swim in sufficiently deep water.
  • Treatment is symptomatic in the majority of patients, and emollients and topical corticosteroids are effective for most patients.
  • The diagnosis of cercarial dermatitis can be improved by a complex approach, including differential cell counts, dynamics of selected cytokines, and dynamics and quality of antibody response.

References

Research

[Cercarial dermatitis].

Presse medicale (Paris, France : 1983), 2004

Research

Prescription Treatment Options.

Advances in experimental medicine and biology, 2017

Research

Prescriptions for atopic dermatitis: oral corticosteroids remain commonplace.

The Journal of dermatological treatment, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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