Wednesday, December 09, 2009
Insect Bite Diagnostic Aid: S-C-R-A-T-C-H
Hernandez and Cohen developed a diagnostic guidelines when they found that a majority of children with a final diagnosis of an insect-bite hypersensitivity reaction had undergone costly, unnecessary and extensive lab tests and skin biopsies before they were referred to Johns Hopkins Children's Center.
This set of principles (termed "SCRATCH") are intended to aid clinicians in making an early and accurate clinical diagnosis of insect bite:
S = Symmetry — Most patients with insect-bite hypersensitivity reactions present with symmetrical eruptions on the face, neck, arms, and legs, with sparing of the diaper area, palms, and soles of the feet.
C = Clusters — Lesions usually appear in a 'meal cluster,' sometimes described as 'breakfast, lunch, and dinner.
R = Rover Not Required — The diagnosis is not dependent on the presence of household pets. Exposure could come from periodic visits to a relative's house, for example.
A = Age-specific — The condition is most prevalent in children between the ages of two and 10.
T = Target Lesions/Time — Bull's-eye-rashes are typical of insect-bite reactions. The time refers to the chronic nature of the eruption and the need for patience and watchful waiting. Parents are advised to prevent secondary infections with appropriate use of nail and hand hygiene and moisturizers.
C = Confusion — Parents are often confused by the conflicting information they have been given, and the referring practitioner may find it hard to accept the diagnosis of an admittedly confusing condition.
H = Household — Unlike scabies or dermatitis, insect-bite reactions may affect only one household members who are hypersensitive
The FULL TEXT of the article by Hernandez and Cohen can be downloaded FREE in pdf format here.
PLEASE NOTE: All contents in this blog are copyrighted materials, unless otherwise stated. Even if you encounter materials in this page without a copyright notice, it does not mean that it is not copyrighted (Click here to read TEN BIG myths on copyright explained). This is especially so as most nations are signatories of the Berne Convention on international copyright law (World Intellectual Property Organization). Nevertheless, I have licensed almost all the materials contained here under Creative Commons licenses strictly for educational, non-commercial purposes only. Kindly email me at firstname.lastname@example.org should you want to use any of the materials for commercial purposes. Thank you.