Psoriatic nails

　　Genetic

　　1, According to clinical observations, the disease often has a family history and shows a genetic tendency. Abroad, it has been reported that 30% to 50% of people with a family history, and even some individuals emphasize up to 100%. In China, it has been reported that about 10% to 20% of people have a family history. Regarding the mode of inheritance, some believe it is autosomal dominant inheritance with incomplete penetrance, while some believe it is autosomal recessive inheritance or X-linked inheritance. If one parent has psoriasis, the incidence rate of offspring is 3 times higher than that of healthy children. If both parents have psoriasis, the incidence rate of offspring is even higher.

　　2, In recent years, it has been found that histocompatibility antigen (HLA) is significantly correlated with psoriasis. Foreign reports show that the antigen frequency of HLA-B13 and HLA-B17 in patients with psoriasis is significantly increased, but there are also reports that the antigen frequency of HLA-B3, HLA-CT7, and HLA-W6 in patients with psoriasis is increased. In addition to the significantly increased antigen frequency of HLA-B13 and HLA-B17 in Chinese patients with psoriasis compared to the normal group, the gene frequencies of HLA-DR7, HLA-A19, and HLA-BW35, HLA-DR9, HLA-C7, and HLA-DQ are also increased. It is currently believed that psoriasis is controlled by polygenes, as well as affected by environmental factors.

　　Infection

　　1, Clinical practice has proven that the onset of psoriasis is related to upper respiratory tract infection and tonsillitis. 6% of patients with psoriasis have a history of pharyngeal infection. We found that many children's psoriasis is closely related to tonsillitis. For example, a mother and her three children simultaneously suffered from acute tonsillitis, and after the disease was controlled, three of them developed psoriasis. Such patients respond well to antibiotic treatment. After the tonsils are removed, the rash can improve or disappear significantly, indicating that infection is an important factor in the onset of psoriasis.

　　2, Some scholars believe that the onset of the disease is related to viral infection. Some have confirmed the presence of eosinophilic inclusions in acanthocytes, but some deny their existence. Some have conducted inoculation experiments on mice, showing similar skin lesions and inclusions in their tissue sections. However, its incidence rate is only 7.5%. Some have conducted experimental inoculation on chicken embryos, with a success rate of 86.7%, and the cells of the disease show vigorous nuclear division. The DNA increases, so the virus theory seems to have some basis, but so far, the virus has not been cultured.

　　3, Recently, Liu Zhengyu and others in China have studied the relationship between human cytomegalovirus (HCMV) infection and the onset of psoriasis, detecting the positive rates of HCMV-specific IgM, IgA antibodies in serum and HCMV-DNA in urine of 86 patients with psoriasis. The results show that the rate of active HCMV infection in patients with psoriasis is significantly higher than that in the control group, and the positive rate of HCMV-DNA in urine of the patients is also significantly higher than that in the control group, indicating that there is active HCMV infection in the body of patients with psoriasis, and its onset is related to the activation of HCMV.

　　3. Metabolic disorders

　　Research on the blood chemistry, skin tissue chemistry, and pathophysiology of psoriasis has not yielded significant results. In the past, some people believed that the onset of psoriasis was related to dyslipidemia. Currently, the etiology of this disease can no longer be considered to be caused by lipid metabolism disorder. Instead, research is more focused on changes in enzyme metabolism. In the normal epidermis, there are four enzymes, but in the skin lesions of psoriasis patients, two of them are missing. After the skin lesions heal, these two enzymes reappear. It is known that the skin lesions of psoriasis lack cyclic adenosine monophosphate (cAMP), which is an epidermal chalone that can inhibit epidermal cell division and maintain a balance between cell growth and death. On the other hand, cAMP has the effect of activating phosphorylase, thus also affecting glycogen metabolism. For example, an increase in epidermal glycogen can lead to an increase in mitotic division of epidermal cells and an increase in turnover rate. However, the metabolic abnormalities in psoriasis are multifaceted, not only the lack of cAMP, but also the increase in cyclic guanosine monophosphate (cGMP), free arachidonic acid, polyamines, and other substances on the surface of the skin lesions play an important role in the proliferation of epidermal cells.

　　1. Loss of protein and other nutrients. Due to the large amount of desquamation in psoriasis, the protein, vitamins, and folic acid in the skin are lost. If the skin lesions last for many years without healing and spread throughout the body, it can lead to hypoproteinemia or malnutrition anemia. Clinical manifestations include fatigue, drowsiness, pale complexion, and a tendency to catch colds. If insufficient nutrition intake due to incorrect 'dietary restrictions' further aggravates the above symptoms.

　　2. Generalized pustular psoriasis leads to organ damage. Some patients with common psoriasis may suddenly develop high fever, joint swelling and pain, general malaise, and an elevated white blood cell count. The skin quickly shows millet-sized, dense pustules. The pustules merge into large areas, dry up, and new pustules develop under the skin, recurring repeatedly for several months without regression. This is generalized pustular psoriasis. This disease often complicates with liver, kidney, and other systemic damage, and can also be life-threatening due to secondary infection, electrolyte disorder, or failure.

　　3. Psoriatic arthritis leads to joint damage. Psoriatic arthritis, in addition to psoriasis damage, also exhibits symptoms of rheumatoid arthritis. Clinical manifestations include joint swelling, pain, limited mobility, morning stiffness, and even joint effusion or deformation. Over time, joints can become rigid. X-ray examination shows changes consistent with rheumatoid arthritis, but rheumatoid factor tests are negative. Some patients may have an increased erythrocyte sedimentation rate and can be accompanied by systemic symptoms such as fever. The course of joint psoriasis is chronic, often lasting for years and difficult to cure.

　　4. Erythrodermic psoriasis is rare but severe. It is manifested by general erythema or dark redness of the skin, swelling, or accompanied by exudation, covered with a large amount of dandruff-like scales. Patients may have headaches, fever, aversion to cold, and other systemic discomforts, enlargement of superficial lymph nodes, and increased white blood cell count. If not treated promptly and correctly, it is easy to cause death. Due to the large area of skin lesions, bacteria are easy to invade, leading to sepsis and death; due to increased blood viscosity and insufficient blood volume, leading to heart failure and death; or due to liver and kidney failure, leading to death.

　　5. Psoriasis is not only unattractive but also affects the whole body, so patients should not take it lightly and should not misuse inappropriate medications to avoid causing greater harm.

　　Nail lesions are relatively common in psoriasis, with an incidence rate of 10% to 50%. The common manifestations are as follows:

　　1. Nail concave points:The most common, which can affect 1 to all nails, with nails more likely to be affected, shallow concave points with small indentations, generally not exceeding 1mm, irregularly scattered, occasionally arranged in a linear pattern with equal spacing. It is caused by the psoriasis changes of the matrix that form the superficial nail plate. When the proximal nail fold grows out, the incomplete keratinization of the psoriasis stratum corneum peels off to form typical concave points.

　　2. Nail separation:Starting from the distal nail margin but not exceeding 1/2 of the nail, the separated nail plate is grayish yellow due to the large accumulation of blood glycoprotein, which is often seen when there is inflammation under the nail skin and nail bed.

　　3. Under-nail thickening:The nail bed and the distal nail plate have psoriasis damage, leading to hyperkeratosis under the nail.

　　4. The nail plate loses its luster:Whitening, thickening, unevenness, even fracturing and peeling off.

　　5. Cracked bleeding:Psoriasis nails are also common, with a higher incidence rate of non-寻常型 psoriasis nails, and the changes are more serious, especially in the case of continuous acrodermatitis in pustular psoriasis.

　　1. After the clinical cure of psoriasis, the immune function, microcirculation, and metabolism have not fully returned to normal. Generally, it takes 2-3 months to recover. Therefore, after clinical cure, that is, after the complete regression of the skin lesions, 2-3 courses of medication should be continued for consolidation. Do not stop the medication abruptly after the skin lesions have regressed, but gradually reduce the dosage to prevent relapse.

　　2. Eliminate mental stress factors, and patients should try to control their emotions, maintain a peaceful mood, avoid overfatigue, and pay attention to rest. Sedatives can be taken in moderation if necessary.

　　3. In daily medication, antimalarial drugs and beta-blockers can induce or worsen the condition, so they should be avoided as much as possible.

　　4. Try to avoid the occurrence of colds, tonsillitis, and pharyngitis as much as possible. Once they occur, treat them actively and appropriately to prevent exacerbation of psoriasis.

　　5. Living in damp environments, getting wet, wading, wind and cold, and sun exposure may all induce psoriasis.

　　Abnormal manifestations of skin living cell examination:

　　1. Regular and elongated skin protrusions and lower thickening.

　　2. Prolongation and edema of the dermal papillae.

　　3. Disappearance of the granular layer.

　　4. Incomplete keratinization.

　　5. MUNRO pustules.

　　1. Pay attention to eating more fresh vegetables and fruits in daily life, eat more foods rich in protein and vitamins, avoid eating spicy and刺激性 foods, and avoid smoking and drinking.

　　2. Pay attention to eliminate factors of mental tension, patients should try to control their emotions, try to maintain a calm mood, avoid overfatigue, and pay attention to rest. Sedatives can be taken in moderation if necessary.

　　3. Avoid factors that may induce psoriasis, such as living in damp environments, getting wet, wading, wind and cold, and sun exposure.

　　I. Treatment

　　The main treatment is for skin lesions. When the skin lesions improve, the nail lesions also improve. If the nail lesions are the main contradiction, the following treatment methods can also be adopted:

　　1. Apply 1% fluorouracil solution topically to treat thickened and punctate concave nail lesions twice a day, using about 25ml per month, for a total of 6 months.

　　2. Fluocinolone nocturnal wrapping should not be used for a long time as it can cause atrophy of the soft tissue around the nail.

　　3. The disadvantage of using a needle-free syringe to inject a low concentration of triamcinolone acetonide (Kenalog) solution (10mg/ml) around the nail is that needle-free syringes are difficult to sterilize and are prone to viral infection, so it is best not to use them.

　　4. Before wrapping the normal skin around the nail with 40% urea ointment (urea 40.0, anhydrous lanolin 20.0, wax 5.0, white vaseline 35.0), protect it with adhesive tape first, then apply the 40% urea ointment to the diseased nail, cover it with plastic film, and seal it with adhesive tape. Alternatively, it is best to use a rubber finger protector cut out and then fixed with adhesive tape for 4-10 days (average 7.2 days) after which the diseased nail can become soft. It can be separated and removed with simple instruments.

　　II. Prognosis

　　The incidence of nail changes in atypical psoriasis is relatively high, and the changes are also severe, especially in the case of pustular psoriasis with continuous acrodermatitis.