BACKGROUND/AIM Varicella is a common and benign disease of childhood. Complications are rare, but in some patients, even without risk factors, severe, life treathening complications could be seen. The aim of this study was to establish the type and frequency of varicella complications among hospitalised patients over an 8-year period. METHODS This retrospective analysis included medical charts of the patients hospitalised in the Infectious Disease Clinic, Belgrade, Serbia, from 2001-2008 (4.85% of all registered patients with varicella in Belgrade, 2001-2008). Among hospitalised patients dermografic characteristics were analysed: hospitalisation lenght, presence and type of complications, presence of immunocompromising conditions and outcome of the disease. The diagnosis of varicella was made on clinical grounds, and in persons >40 years, with negative epidemiological data of contacts, serological confirmation (ELISA VZV IgM/IgG BioRad) and avidity of IgG antibodies were done to exclude the possibility of disseminated herpes zoster. RESULTS A total of 474 patient were hospitalised over an 8-year period. The age of patients was from 5 months to 75 years (mean 22.4 +/- 16.1, median 23.5 years). The majority of patients were adults (n=279; 58.9%) and 195 (41.1%) patients were < or =15 years old. Complications were found in 321/474 (67.7%) patients. The registered complications were: varicella pneumonia (n=198; 41.38%), bacterial skin infections (n=40; 8.4%), cerebelitis (n=28; 5.9%), bacterial respiratory infection (n=21; 4.4%), viral meningitis (n=10; 2.31%), encephalitis (n=9; 1.9%), thrombocytopenia (n=2; 0.4%); 11 (2.3%) patients had more than one complication, among them were sepsis, myopericarditis and retinal hemorrhages. When complications were analysed according to the age, there were no statistical significance, but when type of complication was analysed statistical significance was found (p < 0.05). In adults, pneumonia was the most common complication: 173/279 (62%), followed by skin infections (2.9%), bacterial respiratory infections (2.2%), and more than one complication (2.3%). Pneumonia was more common in adults than in children (7:1). In children skin infections were the most common complications (16.4%), followed by cerebelitis (13.3%), viral pneumonia (12.8%), bacterial respiratory infections (7.7%), encephalitis (3.6%), and more than one complication (4.1%). Neuroinfections were more common in children than in adults (6:1), as well as bacterial skin infections (4:1). Two patients died (0.4%). CONCLUSION There was no difference in the incidence of varicella complication in children and adults, but the type of complication differed. In children the most common complications were skin and neurological infections, while in adults it was varicella pneumonia. These data provide a baseline for estimating the burden of varicella in Belgrade and support the inclusion of varicella vaccine in childhood immunisation program in Serbia.