PANDEMIC INFLUENZA A (H1N1) 2009 PRESENTING AS A MILD DISEASE IN CHILDREN IN A CROATIAN CLINICAL CENTRE.

Pandemic influenza A virus (H1N1) 2009 causes a disease that is epidemiologically and clinically not significantly different from seasonal influenza, but there are differences. The aim of the study was to display and compare epidemiological and clinical characteristics of pandemic influenza in children. At Dr. Fran Mihaljevic University Hospital for Infectious Diseases in Zagreb, in the first two seasons, the incidence of pandemic influenza virus A (H1N1) in particular was exhaustively analyzed only in patients with laboratory-confirmed pandemic influenza A virus (H1N1) 2009. In hospitalized children with documented influenza pandemic, moderate form of the disease predominated, which ultimately meant shorter hospital stay and fewer complications. Otitis media was the rarest complication in children in both seasons. In conclusion, children younger than 5 years, especially boys, were vulnerable groups for pandemic influenza, presenting as a mild disease with low mortality and few complications. Most of the affected children with influenza did not have important risk factors such as asthma and obesity, highlighted by other authors as significant risk factors.

Different features of influenza A H1N1pdm09 virus infection among adults in 2009/10 and 2010/11.

INTRODUCTION: Influenza A H1N1pdm09 virus infection causes an epidemiologically and clinically severe disease mostly characterized by pneumonia, resulting in a high mortality rate. The purpose of this study was to investigate and compare epidemiological and clinical characteristics of influenza A H1N1pdm09 virus infection in patients hospitalized during the pandemic (2009/10) and post-pandemic seasons (2010/11). METHODOLOGY: The data of patients with laboratory-confirmed influenza A H1N1pdm09 virus infection hospitalized and treated at the University Hospital for Infectious Diseases Dr. Fran Mihaljevic in Zagreb, Croatia in the first two seasons of appearance were analyzed. RESULTS: Compared to the pandemic season, in the post-pandemic season, patients were hospitalized longer, had higher values of inflammatory parameters, and were more often treated with antibiotics. The total number of risk factors in patients did not vary significantly between the two seasons. In the pandemic season, a significantly higher number of obese patients and patients with chronic lung disease was observed, whereas in the post-pandemic season, a statistically significant number of patients presented with symptoms of chronic cardiac and neuromuscular diseases. Primary viral pneumonia was frequently registered in younger adults during the pandemic season, whereas in the post-pandemic season, there were more cases of bacterial pneumonia. CONCLUSIONS: During the pandemic season, the influenza A H1N1pdm09 virus infection caused a severe disease with rare bacterial complications, especially in adult patients. The common characteristics of the influenza A H1N1pdm09 virus were lost in the post-pandemic season, assuming the shape and characteristics of the seasonal influenza A virus.

Electrocardiographic changes in hospitalized patients with leptospirosis over a 10-year period.

BACKGROUND: The aim of this study was to investigate the incidence and type of ECG changes in patients with leptospirosis regardless of clinical evidence of cardiac involvement. MATERIAL/METHODS: A total of 97 patients with serologically confirmed leptospirosis treated at the University Hospital for Infectious Diseases "Dr. Fran Mihaljevic" in Zagreb, Croatia, were included in this retrospective study. A 12-lead resting ECG was routinely performed in the first 2 days after hospital admission. Thorough past and current medical history was obtained, and careful physical examination and laboratory tests were performed. RESULTS: Abnormal ECG findings were found in 56 of 97 (58%) patients. Patients with abnormal ECG had significantly elevated values of bilirubin and alanine aminotransferase, lower values of potassium and lower number of platelets, as well as more frequently recorded abnormal chest x-ray. Non-specific ventricular repolarization disturbances were the most common abnormal ECG finding. Other recorded ECG abnormalities were sinus tachycardia, right branch conduction disturbances, low voltage of the QRS complex in standard limb leads, supraventricular and ventricular extrasystoles, intraventricular conduction disturbances, atrioventricular block first-degree and atrial fibrillation. Myopericarditis was identified in 4 patients. Regardless of ECG changes, the most commonly detected infection was with Leptospira interrogans serovar Australis, Leptospira interrogans serovar Saxkoebing and Leptospira kirschneri serovar Grippotyphosa. CONCLUSIONS: The ECG abnormalities are common at the beginning of disease and are possibly caused by the direct effect of leptospires or are the non-specific result of a febrile infection and metabolic and electrolyte abnormalities. New studies are required for better understanding of the mechanism of ECG alterations in leptospirosis.