Syphilis (lues) is a major public health problem worldwide. Despite the preventive measures taken, syphilitic infection caused by Treponema pallidum remains the cause of serious health problems in patients up to persistent disability and death. In recent years, there has been a tendency to increase the number of latent and late forms, incl. cardiovascular syphilis and neurosyphilis in Russia. At the same time, the relevance of timely and adequate laboratory diagnosis of syphilitic infection remains. Despite the existing possibilities of using laboratory methods for diagnosing syphilis, establishing the correct diagnosis often presents a certain difficulty for doctors of clinical specialties related to dermatovenereology. The authors present an interesting clinical case of gummous brain lesions (cerebral syphilis), when clinicians were unable to timely establish the correct diagnosis for the patient during her lifetime. In this regard, it is necessary to regularly improve the skills of doctors of various specialties in matters of epidemiology, clinical manifestations and early laboratory diagnosis of syphilitic infection. The timely use of laboratory methods and the correct interpretation of the results obtained will reduce the number of incorrectly established diagnoses and choose the right therapeutic strategy.

Keywords: neurosyphilis, late syphilis, underdiagnosis, anemia, death