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Categorization of and comments on isomorphic and isotopic skin reactions

Stefano Caccavale1, Ajith Prasanna Kannangara2, Eleonora Ruocco1

  • 1Department of Dermatology, Second University of Naples, Naples, Italy.

Clinics in Dermatology
|December 13, 2016
PubMed

Insights

Locus minoris resistentiae (lmr) signifies areas of lesser bodily resistance to disease, exemplified by the Köbner phenomenon. Locus maioris resistentiae (LMR) represents the opposite, areas of greater resistance, like the Renbök phenomenon.

Area of Science:

  • Dermatology
  • Pathophysiology
  • Immunology

Background:

  • The concept of 'locus minoris resistentiae' (lmr) describes body sites with reduced resistance to disease.
  • The Köbner phenomenon in dermatology is a classic example of lmr.
  • This study introduces 'locus maioris resistentiae' (LMR) as a contrasting concept.

Purpose of the Study:

  • To define and introduce the concept of locus maioris resistentiae (LMR).
  • To differentiate LMR from the established concept of lmr.
  • To provide examples of LMR, such as the Renbök phenomenon.

Main Methods:

  • Conceptual definition and elaboration of LMR.
  • Comparative analysis between lmr and LMR.
  • Review of dermatological phenomena illustrating LMR.

Main Results:

  • Locus minoris resistentiae (lmr) refers to sites of decreased resistance to disease onset.
  • Locus maioris resistentiae (LMR) is defined as sites of increased resistance to disease onset.
  • The Renbök phenomenon serves as a key example of LMR, representing a reverse Köbner's isomorphic response.

Conclusions:

  • The introduction of LMR provides a complementary concept to lmr in understanding disease localization.
  • Understanding LMR enhances the comprehension of how certain body sites exhibit greater resilience to pathological processes.
  • The Renbök phenomenon exemplifies LMR, highlighting areas of enhanced resistance in the body.

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