Initial Evaluation

How To Cure Ringworm Now

Fast Ringworm Cure

Get Instant Access

Although medical school teaches students to perform the history before doing the physical examination, this is not the most efficient way to approach the diagnosis of a skin condition. When the patient has a skin complaint, immediately look at the skin while asking your questions. Look carefully at the lesions and determine the lesion morphology. Table 33-1 provides definitions for the terms used to describe primary and secondary morphology. A magnifying glass and good lighting help to distinguish the morphology of many skin conditions. Next, touch the lesions, with gloves when appropriate. For some lesions, such as actinic keratosis with

Table 33-1 Primary and Secondary Skin Lesions



Primary (Basic) Lesions


Circumscribed flat discoloration (up to 5 mm)


Flat nonpalpable discoloration (>5 mm)


Elevated solid lesion (up to 5 mm)


Elevated solid lesion (>5 mm) (often a confluence of papules)


Palpable solid (round) lesion, deeper than a papule

Wheal (hive)

Pink edematous plaque (round or flat), topped and transient


Elevated collection of pus


Circumscribed elevated collection of fluid (up to 5 mm in diameter)


Circumscribed elevated collection of fluid (>5 mm in diameter)

Secondary (Sequential) Lesions



Excess dead epidermal cells


Collection of dried serum, blood, or pus


Superficial loss of epidermis


Focal loss of epidermis and dermis


Linear loss of epidermis and dermis


Depression in skin from thinning of epidermis/ dermis


Erosion caused by scratching


Thickened epidermis with prominent skin lines

scaling or the sandpaper rash of scarlet fever, lightly feeling the skin provides much information. For deeper lesions, such as nodules and cysts, deep palpation is needed. Observe the distribution of the lesions. Try to determine if the primary lesions are arranged in groups, rings, lines, or merely scattered over the skin.

Determine which parts of the skin are affected and which are spared. Be sure to look at the remainder of the skin, nails, hair, and mucous membranes. Patients often show only one small area and appear reluctant to expose the rest of their skin, especially their feet. With many skin conditions, it is essential to look beyond the most affected area because other areas may provide important clues (e.g., nail pitting when considering psoriasis). Patients may have lesions on their back or feet that they have not observed. For example, a patient may have a papular eruption on the hands or arms that represents an autosensitization reaction (id reaction) to a fungal infection on the feet; not looking for the fungus on the feet will lead to a missed diagnosis (Figs. 33-1 and 33-2). Some skin diseases have manifestations in the

Figure 33-1 Vesicular tinea pedis leading to autosensitization reaction.

Figure 33-1 Vesicular tinea pedis leading to autosensitization reaction.

Figure 33-2 Autosensitization reaction secondary to vesicular tinea pedis (id reaction). © Richard P. Usatine.)

mouth; finding white patches on the buccal mucosa may lead to the correct diagnosis of lichen planus (Fig. 33-3).

Once the physician starts to look at the skin, the patient history will be more focused, directed toward finding the correct diagnosis. The following information assists in making a dermatologic diagnosis and planning treatment:

• Onset and duration of skin lesions: continuous or intermittent?

• Pattern of eruption: Where did it start? How has it changed?

• Any known precipitants, such as exposure to medication (prescription, OTC), foods, plants, sun, topical agents, chemicals (occupation, hobbies)?

• Skin symptoms: itching, pain, paresthesia

• Systemic symptoms: fever, chills, night sweats, fatigue, weakness, weight loss

• Underlying illnesses: diabetes, thyroid disease, human immunodeficiency virus (HIV)

• Family history: acne, atopic dermatitis, psoriasis, skin cancers, dysplastic nevi

The most important in-office examinations of the skin are the following:

Microscopy. To diagnose a fungal infection, scrape some of the scale onto a microscope slide, add 10% potassium

Trichophyton Mouth
Figure 33-3 Oral lichen planus showing Wickham's striae. © Richard P. Usatine.)

hydroxide (KOH) (best with dimethyl sulfoxide [DMSO] and fungal stain), and look for the hyphae of dermatophytes or the pseudohyphae of Candida or Pityrosporum species. Wood's light examination. This is helpful in diagnosing tinea capitis and erythrasma. Tinea capitis caused by Microsporum spp. produces green fluorescence, but Trichophyton spp. do not fluoresce. Erythrasma has a coral-red fluorescence. Wood's lamp also helps distinguish lesions of vitiligo in patients with fair skin.

Surgical biopsy. The biopsy can be used as a diagnostic and treatment tool. Having a reasonable differential diagnosis will help the physician choose shave, punch, or elliptic biopsy.

Was this article helpful?

0 0
Natural Treatments For Psoriasis

Natural Treatments For Psoriasis

Do You Suffer From the Itching and Scaling of Psoriasis? Or the Chronic Agony of Psoriatic Arthritis? If so you are not ALONE! A whopping three percent of the world’s populations suffer from either condition! An incredible 56 million working hours are lost every year by psoriasis sufferers according to the National Psoriasis Foundation.

Get My Free Ebook

Post a comment