[Clinical and epidemiologic characteristics of hemorrhagic fever with renal syndrome in patients treated at the Dr. Fran Mihaljević Clinic for Infectious Diseases in Zagreb].

AIM:The aim of the study was to examine and analyze the main epidemiologic and clinical data of 94 patients with hemorrhagic fever with renal syndrome (HFRS) hospitalized at the University Hospital for Infectious Diseases in Zagreb during the HFRS outbreak in Croatia in 2002. PATIENTS AND METHODS:A total of 110 patients with clinical diagnosis HFRS were treated at the University Hospital for Infectious Diseases in Zagreb. In 110 of HFRS suspected patients, the clinical diagnosis was verified serologically in 94 patients and they were included in the retrospective study. In 93 patients the diagnosis was confirmed by enzyme-linked immunosorbent assay (ELISA), and in one patient by indirect immunofluorescence assay (IFA). Results were analyzed by the use of descriptive statistics. RESULTS:Puumala (PUU) virus infection was verified in 80 (85.1%), Dobrava (DOB) infection in 8 (8.5%) and cross-reactive antibodies to both PUU and DOB viruses in 5 (5.3%) HFRS patients. In one patient who was confirmed by IFA the hantavirus serotype causing HFRS could not be determined. The localities of the presumed HFRS patient exposure to hantaviruses were mostly in the Zagreb area. Most patients were aged 21-50 (83.0%) and male (76.6%). The majority of HFRS cases occurred between May and August (75.5%). A high proportion of HFRS cases were found in the general population from Zagreb and its surroundings (78.7%). The majority of patients were hospitalized in the febrile stage of the disease (70.2%). The main symptoms were: fever (100%), headache (88.3%) and backache (87.2%). Oliguria was recorded in 56.4% and, anuria in 7.5% of patients, however, only three (3.2%) patients required hemodialysis. Six patients developed hemorrhagic manifestations, especially petechiae on the skin and mucosa. One patient in the convalescent stage had subarachnoidal bleeding. Six patients had pathologic electroencephalogram (EEG) findings and two developed epileptic seizures. Lumbar puncture was performed in 12 patients without inflammatory changes in the cerebrospinal fluid. Pathologic ECG findings were recorded in 30/79 (38.0%) patients, primarily including mild and translent disturbances such as sinus tachycardia, sinus bradycardia, nonspecific alteration of the final complex and incomplete right bundle branch block. Conventional chest radiography revealed abnormal findings in 23/84 (27.4%) patients. The abnormalities consisted of interstitial infiltrates and/or pleural effusions and atelectasis. The patients were divided into 4 groups according to the disease severity: mild in 74 (78.7%), moderate in 15 (16.0%), severe in 4 (4.2%), and very severe in one (1.1%) patient. The latter developed multiorgan failure and died. CONCLUSION:The largest outbreak of HFRS to date was recorded in Croatia in 2002. Ninety-four patients with clinical and serologically verified HFRS were treated at the Dr. Fran Mihaljević University Hospital for Infectious Disease, Zagreb. The majority of patients were hospitalized between May and August. Most patients had mild form of the disease primarily caused by PUU virus.