FULL PAPER NEW MICROBIOLOGICA, 41, 1, 61-66, 2018, ISN 1121-7138 Ageing with HIV - a periodontal perspective Boško Toljić 1 , Alexander M. Trbovich 2 , Sanja Matić Petrović 1 , Ibrahim Yousif Kannosh 1 , Gordana Dragović 2 , Djordje Jevtović 2 , Silvio R. De Luka 2 , Jasna L. Ristić-Djurović 3 , Jelena Milašin 1 1 School of Dental Medicine, University of Belgrade, Serbia; 2 School of Medicine, University of Belgrade, Serbia; 3 Institute of Physics, University of Belgrade, Serbia INTRODUCTION Symbiosis of more than 700 different bacterial species is important for maintaining the oral cavity homeostasis (Aas et al., 2005). Physiological roles of the normally pres- ent microbiome are to protect the mouth from invasion of pathogenic microorganisms (Ribet and Cossart, 2015) and to provide metabolites and immune modulators necessary for proper development and functioning of the orofacial system (Ruby and Barbeau, 2002). The oral microbiome is continuously changing along with the ageing process (Zapata and Quagliarello, 2015). These changes are finely synchronized with age-related modifi- cations of developing oral tissues, and with the immune system of the oral cavity, both naive and specific. Alter- ations of immune response caused by human immuno- deficiency virus (HIV) infection usually disturb this bal- ance. Progressive decline in host defense due to age and HIV-related changes makes oral tissues more susceptible to the detrimental effects of various pathogens, as well as to side-effects of antiretroviral therapy. Complex interactions of immune ageing and age-related Corresponding author: Dr Jelena Milašin E-mail: jelena.milasin@stomf.bg.ac.rs ©2018 by EDIMES - Edizioni Internazionali Srl. All rights reserved alterations of oral structures are possible modulators of mouth bacterial load. Although many studies have as- sessed oral microbial flora in HIV-infected patients, none of them have focused on bacterial composition shifts along with the ageing process in this population. The aim of the present study was to investigate temporal changes in oral microflora patterns within two different age groups of HIV-infected individuals on highly active an- tiretroviral therapy (HAART) and to compare them to bac- terial composition changes in non-infected individuals. MATERIALS AND METHODS Subjects This study enrolled 60 HIV-infected male patients, 30 younger (≤35 years) and 30 older (≥50 years) treated at the “Dr Kosta Todorovic” Clinic for Infectious and Tropi- cal Diseases, School of Medicine, University of Belgrade. The average HAART treatment duration was approximate- ly 20 months in the younger population and 114 months in the older population. Basic clinical data related to HIV infection are listed in Table 1. Sixty consecutive HIV- male patients of corresponding age groups (30 younger, 30 old- er), undergoing regular dental check-up at the Clinics of the School of Dental Medicine, University of Belgrade were recruited as controls. In HIV-infected patients, the mean age in the younger group was 29.33±4.20 (mean ±SD) years, and in the older 59.03±8.17 years. In non-in- fected patients, the mean age in the younger group was 29.47±3.47 years, whereas in the older group, the mean Key words: HIV, Ageing, Oral bacteria, Immunosenescence. SUMMARY The importance of oral microflora composition in HIV-infected patients is well recognized. However, no studies so far have dealt with age-related changes in periodontal pathogens occurrence in HIV+ individ- uals. The aim of the present study was to assess and compare temporal changes of bacteria frequency in younger (≤35 years) and older (≥50 years) HIV-infected and non-infected individuals. Bacterial DNA was isolated from buccal swabs of 30 younger and 30 older subjects in both HIV+ and HIV- groups. By means of PCR the following microorganisms were detected: Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Peptostreptococcus micros, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola. Oral and periodontal examinations were performed in all subjects. The preva- lence of microorganisms was significantly higher in HIV+ patients compared to controls, and their distri- bution showed a notable shift. The decreasing incidence in HIV- subjects was: Pi>Pm>Pg>Aa>Ec>Tf>Td whilst in HIV+ it was: Pi>Pm>Ec>Pg>Tf>Aa>Td. Oral manifestations of HIV infection were more frequent in older compared to younger patients. All measured values of clinical periodontal parameters were sig- nificantly higher in older compared to younger HIV+ patients. Ageing in HIV+ subjects is accompanied with a substantial increase and rearrangements of periodontal microflora, potentially aggravating oral and systemic health. Received July 5, 2017 Accepted November 24, 2017