This clinical mind map is based upon the visual appearance of a skin lesion. A basic understanding of the terminology of skin lesions and recognition of primary lesions, such as macule, papule, pustule, and vesicle, is required for a clinician to apply this clinical mind map. Usually when patients present with skin lesions, they show the lesion to the clinician before or while describing the lesion. Therefore, recognizing a lesion at first glance is an efficient way for a clinician to narrow the differential diagnoses. Since several dozens of ailments manifest on the skin, a clinician can be challenged to quickly arrive at the diagnosis. However, practice does help with improvement of this skill. Several history related questions help a clinician further narrow the differential diagnoses. There are very few urgent/emergent situations in relation to skin lesions, such as the acutely dehydrating conditions Toxic Epidermal Necrolysis, Pemphigus, and severe burns.
The mnemonic OLD BEN CAT can be used to memorize a list of questions to gather history. This mnemonic is described in detail in the associated skin lesions mind map.
Typically, if an underlying etiology is infectious (such as viral or bacterial), the infection may result in transient skin lesions, whereas systemic conditions such as autoimmune problems tend to result in recurrent or permanent lesions. A clinician can diagnose most skin conditions based upon a history and a physical exam, and in some situations, a skin biopsy may be needed as a confirmatory test. Blood tests may help to identify certain diagnoses which have systemic involvement, such as autoimmune conditions and infections. Although the skin lesions mind map covers a long list of diagnoses, this map is not comprehensive due to space constraints. Additional diagnoses must be considered when and where indicated clinically.