What causes mouth ulcers in children?

Generally speaking, "烂嘴丫" (sore corners of the mouth) usually refers to angular cheilitis. In children, angular cheilitis may be caused by dry climate, nutritional deficiencies, bacterial infection, fungal infection, viral infection, and other factors. It is recommended to seek timely medical attention and follow the guidance of a physician for treatment. Detailed explanations are as follows:

1. Dry Climate

In dry seasons, low air humidity causes rapid moisture loss from the lips and corners of the mouth, making them prone to dryness and cracking. Children often unconsciously lick their lips, further accelerating moisture evaporation and damaging the skin barrier, which can lead to angular cheilitis. During dry seasons, children can apply specialized lip balm to keep the lips moisturized, and should be reminded not to lick their lips.

2. Nutritional Deficiencies

Picky eating habits in children can lead to deficiencies in B vitamins and zinc. B vitamins are involved in metabolism, while zinc plays an important role in skin and mucosal repair. Deficiencies can impair normal metabolism and repair of the mucous membranes at the corners of the mouth, making the skin fragile and prone to inflammation and erosion. Cultivating good eating habits in daily life, ensuring a diverse diet, and consuming more foods rich in B vitamins are recommended.

3. Bacterial Infection

Bacteria such as streptococcus and Staphylococcus aureus can proliferate at the corners of the mouth, damaging the skin barrier and causing angular cheilitis. Symptoms may include pain and redness. Patients can use medications such as erythromycin ointment, fusidic acid cream, or mupirocin ointment as directed by a physician to alleviate symptoms.

4. Fungal Infection

Fungi such as Candida albicans can multiply at the corners of the mouth, damaging skin tissue and causing angular cheilitis. Symptoms may include white pseudomembranes and itching. Patients can use medications such as clotrimazole cream, miconazole nitrate cream, or itraconazole capsules under the guidance of a physician for treatment.

5. Viral Infection

Viral infections are mainly caused by the herpes simplex virus. The virus replicates at the corners of the mouth, damaging skin cells and causing angular cheilitis. Symptoms may include blisters, pain, and fever. Patients can use medications such as acyclovir tablets, valacyclovir hydrochloride tablets, or compound acetic acid dexamethasone cream under the guidance of a physician for treatment.

In daily life, it is important to help children maintain oral hygiene and rinse the mouth after meals; prevent children from touching the corners of their mouths with their hands; and schedule regular oral checkups to detect and address oral problems promptly.