Keywords
Abstract
Cutaneous tuberculosis is a group of clinically and morphologically different skin diseases caused by Mycobacterium tuberculosis complex. Published epidemiological data on cutaneous tuberculosis are not systematic, scarce and often contradictory. The authors share their experience in creating a mathematical model of the dynamics of the prevalence of cutaneous tuberculosis St. Petersburg based on data for 46 years of observation (1971-2017) using polynomial, logarithmic and exponential approximation methods. The study of the cohorts of patients with cutaneous tuberculosis in all its forms in Leningrad/St. Petersburg showed that the prevalence of cutaneous tuberculosis in St. Petersburg over the past 46 years has decreased 142 times from 7.1 (1971) to 0.05 (2017) per 100 000 population. Polynomial approximation of a polynomial of the 4th degree has the form: y = 7E-06x4 -- 0,0008x3 + 0.0356x2 - 0.7621x + 7.9729 (R?=0,9836). The prognosis of further dynamics of cutaneous tuberculosis prevalence in St. Petersburg for the period 2018-2022 is based on exponential extrapolation: y=8,8021e-0,088x (R?=0,94). In accordance with it, the prevalence of cutaneous tuberculosis in St. Petersburg will continue to decline consistently and will reach the level of 0,027 per 100 000 population by 2022. A necessary condition for the implementation of this forecast is to maintain the stability of the factors affecting the studied process. Active invasive diagnostic tactics and the use of the algorithm of etiological diagnosis of cutaneous tuberculosis will minimize diagnostic errors and reduce the diagnostic period.