Public condition directory
Browse public condition summaries from China medical resources by stable specialty category.
Niacin deficiency
Pellagra is a disease caused by a deficiency of niacin (vitamin B3) or its precursor, tryptophan, due to various reasons. It primarily affects the skin and mucous membranes, digestive system, and neuropsychiatric system. It can occur at any age, but in China, it is more common in young and middle-aged women. Clinically, it manifests as dermatitis, diarrhea, and dementia.
View detailsHyperkeratosis of the Nipple and Areola
Nipple and areola hyperkeratosis is a rare disease characterized by hyperkeratosis, hyperpigmentation, and verrucous growth of the skin of the nipple and areola.
View detailsPsoriasis
Psoriasis, commonly known as "cowhide癬" (niupi xuan), is a chronic scaly skin disease caused by the interaction of multiple factors. It is difficult to treat and highly prone to recurrence, belonging to an immune disease with a certain genetic predisposition. Typical manifestations include scaly erythematous plaques or patches, localized to one area or widely distributed throughout the body. Psoriasis is more common in adults, but children and adolescents can also be affected. Most patients experience worsening or recurrence in winter and remission in summer.
Eczema
Eczema is an inflammation of the superficial dermis and epidermis caused by various internal and external factors. In the acute phase, skin lesions are mainly papulovesicles with a tendency to exudate, while in the chronic phase, lichenification predominates. It is prone to recurrent attacks. Eczema affects a wide range of people, regardless of age, gender, or region.
View detailsWart
Warts are benign growths on the skin surface caused by human papillomavirus (HPV) infection. They can occur on various parts of the body and are contagious, transmissible through direct contact with an infected person's skin or indirect contact with contaminated objects. HPV infection is very common, with most people experiencing it at some point in their lives. Warts can occur at all ages, being rare in infants and young children. The incidence gradually increases with age, peaking in young and middle-aged adults.
View detailsHerpes zoster
Herpes zoster, commonly known as shingles, is an infectious disease affecting the nerves and skin, caused by the varicella-zoster virus. It is named "herpes zoster" because the rash typically appears in a band-like pattern. Herpes zoster is most common in older adults and individuals with weakened immune systems. It is self-limiting, but if left untreated, it can lead to significant nerve damage.
View detailsTinea
Tinea is a general term for a group of diseases caused by dermatophytes invading the skin, hair, and nails of humans and animals. It manifests as skin lesions such as erythema, blisters, and pustules, with significant itching.
View detailsPruritus
Skin itching can be localized to a specific area or generalized throughout the body. It is often paroxysmal and more severe at night. It is common in clinical dermatology, affecting more women than men, more Asians than Caucasians, and is more prevalent in autumn and winter. Symptoms gradually worsen with age. Skin dryness, underlying diseases, allergies, and irritation can all cause skin itching.
View detailsHair loss
Hair loss refers to the phenomenon of hair shedding. It is normal to lose 50-100 hairs per day, which is a natural metabolic process of hair and does not require concern or treatment. If more than 100 hairs are lost per day, or significantly more than usual, accompanied by a decrease in overall hair volume or density, reduced hair in a specific scalp area, or the appearance of bald patches, it is considered abnormal hair loss. Hair loss can be divided into non-scarring alopecia and scarring alopecia. Non-scarring alopecia includes androgenetic alopecia (formerly known as "seborrheic alopecia"), telogen effluvium, alopecia areata, etc. The main causes of hair loss include: Androgens: Patients with androgenetic alopecia have elevated dihydrotestosterone levels, leading to hair loss. Patients who have had their testicles removed due to tumors do not develop the condition, indicating the important role of androgens in hair loss. Genetics: Children of parents with hair loss have a higher risk of developing the condition than others. Mental stress: Excessive mental stress often leads to increased hair loss. Under mental stress, the arrector pili muscles contract, hair stands erect, and the function of the autonomic or central nervous system becomes disordered. This leads to changes and malnutrition in the hair follicles and dermal papillae, thereby inhibiting hair growth function, causing hair to enter the telogen phase, and resulting in hair loss. Medications: Chemotherapy drugs, blood thinners, high blood pressure medications, and contraceptives can all cause temporary hair loss. Nutrition: Hair is an external manifestation of the body's condition. Malnutrition and abnormal metabolism can cause changes in hair quality and color, and severe malnutrition can even lead to diffuse hair loss. Autoimmune diseases: Autoimmune diseases can cause alopecia areata. Dyes and other chemicals: Frequent use of shampoos, perms, bleaching, and hair dyeing can cause hair thinning. Others: Burns, various injuries, and X-rays can also cause temporary hair loss. Once the cause is removed, hair will resume growth. In addition, thyroid diseases, lupus erythematosus, diabetes, and other conditions can also cause hair loss.
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