PA 510 Week 3 Distribution Pattern Analysis Example

Distribution Pattern Analysis: Wrists, Shins, a Line Along a Forearm Scratch and the Inside of Both Cheeks, With Every Clear Region Named

Student Name

Chamberlain University

PA 510: Comprehensive Clinical Module Dermatology

Instructor Name

Month Day, Year

Distribution Pattern Analysis: Wrists, Shins, a Line Along a Forearm Scratch and the Inside of Both Cheeks, With Every Clear Region Named

Two Claims Kept Apart

This analysis makes two separate claims about D.O.'s eruption, one at close range and one across the body. The full skin examination was done in a gown with the patient's permission, in good light, front and back, including the scalp, mouth, nails, palms and soles. The genital examination was offered and declined, and that region is recorded as not examined.

Close Range: How the Lesions Sit Together

On the wrists and forearms, papules are grouped in clusters of five to fifteen, with normal skin between most of them. On both shins, papules have merged into larger plaques, the largest 6 by 4 centimeters on the left, with thick gray-white scale. On the left forearm, about twelve papules run in a straight line 7 centimeters long along a scratch the patient remembers making on a pallet strap about four weeks ago. Lesions appearing along a line of injury are known as the Koebner phenomenon, which is characteristic of lichen planus among other conditions (Le Cleach & Chosidow, 2012). I have recorded the line as a close-range finding and noted its history, but I have not made it the basis of a diagnosis.

Across the Body: Regions Involved

Flexor surfaces of both wrists and the lower third of both forearms. Front of both shins, from just below the knee to the ankle. Lower back, a scattered group of about ten papules. Inside of both cheeks in the mouth: a lacy white network on the buccal mucosa, about 2 by 1 centimeters on each side, not wiped off with gauze, painless.

The Regions Recorded Clear

Face, including the lips and eyelids: clear. Scalp: clear, with no hair loss or scarring. Neck, chest and abdomen: clear. Upper arms and the extensor forearms: clear. Palms and soles: clear of the eruption; a separate pigmented spot on the left sole is noted and will be examined on its own. Thighs and buttocks: clear. Fingernails and toenails: no ridging, thinning or splitting. Genital area: not examined, declined. Naming these is what makes the pattern claim checkable; a reader who sees "wrists and shins" without them cannot tell whether the face was looked at.

Symmetry as a Comparison

The eruption is symmetric in the sense that both wrists and both shins are involved to a similar degree: 30 to 40 papules on each wrist and forearm, and plaques on each shin, the left larger. Symmetry is a comparison between sides, and both sides were examined; the claim would not be possible from photographs of one side only. The single linear group on the left forearm is asymmetric and has a separate explanation.

Where the Pattern Stops

On the shins, the plaques stop at the ankle and do not involve the top of the foot. On the forearms, the lesions stop below the elbows. Edges where the eruption stops are part of the pattern, because a process confined to flexural wrists, shins and mouth points a reader differently from one involving the trunk widely or the sun-exposed face and backs of the hands.

What the Pattern Suggests, and Does Not

Flexor wrists, shins, the lower back, linear lesions along a scratch and a lacy network inside the cheeks together form the pattern most often described in lichen planus (Le Cleach & Chosidow, 2012). A lichenoid reaction to a medicine can look similar but is more often widespread and may favor sun-exposed areas; the clear face and backs of the hands are recorded for that reason. The pattern narrows the question but does not answer it.

Mucosa and Nails, Looked At on Purpose

The mouth and nails were examined deliberately rather than as an afterthought, because they change what the pattern means. A lacy white network inside both cheeks is found in a large share of people with lichen planus of the skin and is often painless, so patients rarely mention it (Le Cleach & Chosidow, 2012). Its presence here strengthens the skin pattern; its absence would not have ruled it out. Nails were examined because lichen planus can thin, ridge or split them and sometimes scar the nail fold; all twenty nails looked normal, which is recorded as a finding and not left blank. The scalp was parted in several places to look for scarring hair loss, which was absent.

Diagram and Prose Agreeing

The body diagram attached to the note shades the wrists, forearms, shins and lower back, marks the forearm line with a single stroke and marks both cheeks on the mouth inset. Every shaded area is named in the prose above, and no area named in the prose is left unshaded.

References

Le Cleach, L., & Chosidow, O. (2012). Lichen planus. New England Journal of Medicine, 366(8), 723-732. https://doi.org/10.1056/NEJMcp1103641