Psoriasis is a relatively common skin disease that can have a negative impact on the quality of life and appearance of patients. However, there are many other “relatives” of psoriasis in life that have so many similarities to psoriasis that these “relatives” need to be carefully differentiated in clinical practice and may be misdiagnosed if not careful.
Differentiating psoriasis from seborrheic dermatitis
Seborrheic dermatitis occurs on the head and face, anterior sternum, armpits and groin, while psoriasis usually affects the entire body. The factors for both diseases are not yet fully understood, and seborrheic dermatitis may be associated with age, gender, and genetic factors, while psoriasis patients consider that it may be caused by a combination of genetic and environmental factors.
Seborrheic dermatitis
For example, patients with seborrheic dermatitis on the head and face may have bran-like flaking or greasy flaking with mild itching, or in severe cases, greasy yellow or brown crusts with vesicles, oozing, and an odor of sebum breakdown. In contrast, patients with psoriasis occurring on the head and face usually present with white scales, itchy, burning, dry skin, and even bleeding.
Differentiating psoriasis from tinea capitis
Tinea capitis, as the name implies, is a fungal infection of the skin that occurs on the head and can be contagious, but psoriasis is not a contagious disease and the cause is usually related to genetic and environmental factors. The cause is usually related to genetic and environmental factors. Tinea capitis usually occurs mainly on the scalp, but psoriasis can develop throughout the body.
Tinea capitis
Symptoms of tinea capitis can manifest as different types of lesions on the head, including yellow ringworm, white ringworm, black spot ringworm, and pustular ringworm, which are usually accompanied by loose hair, easy breakage, loss of hair, and may even cause permanent hair loss. However, patients with psoriasis usually do not suffer from hair loss even if the lesions occur on the scalp area, and can be differentiated from this.
Differentiating psoriasis from stage II syphilis rash
Psoriasis and second-stage syphilis are two very different diseases, and there is a fundamental difference between the two in terms of etiology. Syphilis is a sexually transmitted disease, usually due to impure sex or mother-to-child transmission. Psoriasis, on the other hand, is a spontaneous skin disease that is related to genetic and environmental factors.
Symptoms of syphilis to the second stage are similar to those of psoriasis, and a generalized syphilis rash may appear, manifesting as reddish-brown or copper-red papules and papules, and some patients may have pustules and ulcers on the skin and mucous membranes. The most important thing is that the patient has a history of impure sex and a history of hard chancre or contact with syphilis, which is not always present in psoriasis.
Differentiating psoriasis from lichen planus
The causes of both psoriasis and lichen planus are not completely clear. Psoriasis is usually related to genetic and environmental factors, while lichen planus may be related to a variety of factors such as immunity, genetics, infection, neurological factors, and medications. The main symptoms of lichen planus are deformation of the nails or toenails and damage to the oral mucosa and genital mucosa, while psoriasis patients usually have generalized skin damage.
Patients with lichen planus may develop polygonal flat purple-red papules that may fuse into plaques and usually involve the buccal mucosa, gums, and tongue edge, with white streaks and plaques, whereas patients with psoriasis do not usually develop these symptoms.
In addition, patients with lichen planus may also have damage to specific genital mucosa, for example, men may have lesions on the glans and foreskin in a circular arrangement; women may have lesions on the inner labia majora, labia minora, vestibule, etc., similar to those on the oral mucosa, which are not usually present in patients with psoriasis.
Differentiating psoriasis from chronic eczema
Although chronic eczema and psoriasis are somewhat similar in terms of etiology and symptoms, there are still certain differences. For example, while patients with chronic eczema are also affected by genetic and environmental factors, common causes include abnormal immune system function and endocrine metabolic changes.
Comparison of eczema (left) and psoriasis (right)
Although both can have generalized lesions and itching, and patients with chronic eczema can also have flaking, patients with chronic eczema usually do not have other systemic damage, for example, their fingernails or toenails are not usually involved; patients are often sensitive and can have other allergic disease symptoms such as hives, asthma, allergic rhinitis, etc., whereas patients with psoriasis usually do not have these diseases or symptoms. symptoms.
In summary, although these “relatives” have some similarities with psoriasis, they are not completely indistinguishable. If some skin discomfort symptoms appear in life and the patient may not be able to accurately identify them with his or her own judgment, he or she should go to a hospital dermatology department in a timely manner.
References
[1]Shi Yuling. Interpretation of the Chinese psoriasis diagnosis and treatment guidelines (2018 edition) [J]. Journal of Tongji University (Medical Edition),2019,40(03):265-267.