In the present article, relevant data on the characteristics of the course of infections transmitted through sexual contact (hereinafter STIs) are considered at the present stage. Particular attention is paid to mixed infections, in particular the combination of syphilis and HIV. Since the presence of both infections in a patient simultaneously significantly complicates the clinical picture, and also contributes to their spread in the population, which is an acute social problem. The article presents modern data on the epidemiology, level and dynamics of the incidence of syphilis and HIV infection in the Russian Federation, including among high-risk groups. Research data on the incidence of STIs (urogenital infections caused by Mycoplasma genitalium, Ureaplasma spp., Mycoplasma hominis, Chlamydia trachomatis, syphilis) and viral hepatitis B and C in 60 HIV-positive prisoners in the Kirov region are presented. The features of the development and course of syphilitic infection, the difficulties of diagnosis and therapy that occur with HIV are described. A case of own clinical observation of the malignant course of syphilis associated with HIV infection is presented. Both infections have been identified in the hospital where the patient is admitted with a diagnosis of spreading pyoderma, exhibited on the basis of complaints and clinical picture (ektimatoznye rash).

The article presents a clinical case of papulopustular rosacea from our own practice. First of all, the patient's anamnesis is extremely interesting: family history (his brother has episodes of reddening of the face), the onset of rosacea against the background of a stressful situation, the presence of gastric diseases, the connection with nutritional factors. One of the first mentions of rosacea belongs to Avicenna, who in his writings described the clinical picture of rhinophyma ("badschenan", later renamed "abedsamen"). The pineal nose, dotted with "serpentine" vessels, has traditionally been associated with excessive drinking. Currently, the role of alcohol as an etiological factor is not paramount, but its aggravating effect has been proven. Despite the typical picture of rosacea, our patient has been receiving therapy for seborrheic dermatitis and other diseases several times over the course of several years. Probably, the specialists had doubts about the possible diagnosis of rosacea in a male patient under the age of 30.

The article presents clinical cases of syphilitic infection from our own practice, which were not recognized by doctors of related specialties at the early stages of the development of the disease. In the first observation, the manifestations of syphilis were regarded as a surgical pathology in the patient, which entailed surgical intervention, which was not necessary as such. The following clinical case demonstrates lesions of the mucous membranes in syphilis, mistakenly recognized by the therapist as streptococcal angina. The atypical hard chancre in the final observation disorientated the surgeon, that led to a delay in the correct diagnosis and, accordingly, in the appointment of adequate treatment. Regardless of the specialty, everyone should not forget about the variety of manifestations of syphilis in all periods. The lack of alertness among doctors of related specialties contributed to the delayed diagnosis and the appointment of specific anti-syphilitic therapy.