A.N. MAKSUDOVA1, T.N. KHALFINA1, G.I. NURULLINA1, G.M. ISLAMOVA2, G.R. LOTFULLINA1  1Kazan State Medical University, Kazan 2Republic Clinical Hospital, Kazan  Contact details: Maksudova A.N. — MD, Professor of the Department of Hospital Therapy Address: 49 Butlerov St., 420012 Kazan, tel.: +7 (843) 290-18-20, e-mail: adelyamaksudova@gmail.ru The article examines the literature data reflecting the difficulties of diagnosing primary […]