Relevance. Beau's lines (Beau's grooves, Beau's lines) are one of the most common types of onychodystrophy. Beau's lines occur for many reasons, both external and internal.External causes include: previous inflammation or trauma to the posterior nail fold, damage to the nail skin (cuticle, epinohia), inflammation in the upper part of the fingers and nail area, fungal nail infection, heavy physical exertion, prolonged exposure to low temperatures. Internal factors include: side effects of chemotherapy, serious illnesses (myocardial infarction, pulmonary embolism, shock, high fever), metabolic disorders, eczema, psoriasis, especially if the rash is located on the back of the hands, uncontrolled use of potent drugs, infectious diseases that disrupt the function and nutrition of the nail matrix, general intoxication of the body, stress and past neuropsychiatric diseases, a symptom of latent skin pathologies, rheumatism, pemphigus, diabetes mellitus, malaria, Raynaud's disease. The appearance of Beau's lines has been described in children who have had measles, scarlet fever and other childhood infections. In recent years, the appearance of Beau's lines has been noted in patients who have had SARS-Cov2 infection, especially in severe cases of the disease, with lung damage and immune system reactions. Materials and methods. The article presents a clinical case of a patient who developed Beau's lines as a result of a sports injury to the distal phalanx of the fingers and subsequently contracted COVID-19. Results. Patient T suffered a sports injury to the distal phalanx in 1987. Five to six weeks after the injury, a specific deformation of the nail plates, similar to a washboard, was observed during examination. Transverse arcuate grooves were observed across the entire surface, crossing the nail plate from one edge of the nail fold to the other, which were identified as Beau's lines. In 2021, patient T suffered from a severe form of COVID-19 with extensive lung damage and was in intensive care for 2 weeks. After 5 weeks, changes in the nail plates were observed in the patient with the appearance of Beau's lines. Conclusions. Damage to the nail plate in the form of Beau's lines is possible both in cases of trauma and in severe conditions of the body. When Beau's lines appear and trauma to the nail bed is ruled out, an in-depth examination is necessary to rule out severe pathology. The time of appearance of Beau's lines in trauma differs from the time of their appearance in severe COVID-19 and averages 5-6 weeks.
M Temirbayev (Mon,) studied this question.