1. What essential question does one still need to ask in order to help make the diagnosis?
2. What is the tentative diagnosis?
3. Can you list at least three differential diagnoses?
4. What features of this condition differentiate it from other conditions in your differential diagnosis?
5. What is the suitable treatment for this condition?
Treating A Patient With Multiple, Pruritic Open Lesions On Both Feet
What You Should Know About Factitial Dermatitis
Factitial dermatitis (dermatitis artefacta) means self-inflicted lesions of the skin. The lesions are in sites that are readily accessible to the patient’s hands. In many cases, patient may cause deep excoriations with the fingernails but they may also be caused by sharp instruments such as knives, the application of caustic chemicals and burning, sometimes with cigarettes or matches. The most common locations are the extensor surfaces of the extremities, the tops of the feet, the face, the upper shoulders and back. The patients may or may not be aware that they caused the skin damage themselves, and they usually deny having intentionally inflicted the injury. There are several reasons for patients to self-inflict wounds on their own bodies. Most patients with dermatitis artefacta have some underlying psychological issue that may be caused by stress, anxiety, depression or drugs. If the dermatitis is a single episode that was triggered by a particularly difficult situation (such as divorce, loss of job, death in the family), about 70 percent of all patients will stop the self-injury once the situation is resolved. However, about 30 percent of the cases of dermatitis artefacta are ongoing and recurrent, and represent a long history of psychological problems. Other issues, such as the use of street drugs, especially methamphetamine, may cause some patients to see or feel bugs on their skin (crank bug bites). They attempt to remove them by picking at them until they create open wounds or sores. Patients with factitial dermatitis, in which the skin lesions are directly produced or inflicted by their own actions, usually present with this condition as a result or manifestation of a psychological problem. It could be a form of emotional release in situations of distress, anxiety or depression or part of an attention-seeking behavior (usually seen among younger women). In a few cases, the cause may be an underlying attempt to secure a work-related insurance claim or disability payment. However, in all cases of dermatitis artefacta, the presenting lesions are difficult to recognize and do not conform to those of known dermatoses. In other words, there are no primary skin lesions (those that are a direct expression of a skin disease such as macules, papules, plaques, nodules, vesicles, pustules or cysts). There are only secondary skin lesions (those lesions that follow a skin condition such as ulcers, erosions, excoriations, crusts, scabs, scars or atrophy). This typically will give the doctor a clue as to the origin of the condition. There is a 4:1 female to male ratio for factitial dermatitis. Some associated traits include low self-confidence, generalized apprehension, meticulousness, depressive mood disorder and hypersensitivity to perceived negativism toward themselves. Concurrent symptoms of severe headache or menstrual disorders are common in many of these patients. The lesions in very young children are characteristically not self-inflicted but are caused by abusive adults. There is also a condition called Munchausen’s syndrome by proxy, whereby a parent or guardian will inflict skin injuries on a child in an attempt to convince doctors that their child has a serious dermatitis or needs ongoing medical care. One would diagnose factitial dermatitis via classical clinical findings. A patient’s history may suggest some obvious reasons for the pruritus. These reasons may include preexisting atopic dermatitis, contact dermatitis, insect bites or food allergies. In order to exclude any medical causes of generalized pruritus, physicians may perform the following simple tests: complete blood count with differential; chemistry profile; thyroid-stimulating hormone levels; and fasting plasma glucose level. Patch testing for allergens and fungal cultures may be necessary when the condition appears to be non-responsive to the initial treatment of covering the lesions. Perform the appropriate workup for malignancy if this is indicated by the patient’s history. In persistent cases, a simple biopsy will be beneficial. Xerosis, or generalized dry skin, is the most common cause of pruritus among older patients. These patients usually lack certain fatty acids in the skin that augment hydration and barrier function, leading to the development of dry itchy skin.