Clinical features, treatments and outcomes of influenza A (H1N1) 2009 among the hospitalized patients in the clinic for infectious diseases in Novi Sad

Abstract

Background/Aim. Most infections caused by influenza A (H1N1) 2009 virus are presented by mild respiratory symptoms. However, some patients required admission to the intensive care unit (ICU). In this article we aimed to describe the clinical and laboratory characteristics of the patients with influenza A (H1N1) 2009, antiviral therapy use, the disease outcome and risk factors associated with the severe disease. Methods. The patients with the signs and symptoms of novel influenza A (H1N1) 2009, admitted to the Clinic for Infectious Disease in Novi Sad, were evaluated. The study included 293 patients hospitalized between October 2009 and February 2010. Basic demographic data, underlying medical conditions, clinical signs and symptoms, duration of the disease before the admission, laboratory tests, radiographic findings, treatment, and the final outcome (survived, died) were all noted. Factors associated with severe disease requiring ICU admission were determined by comparing the ICU cases with control groups of the patients admitted to the hospital but not to ICU. Results. The average age of the patients was 32.72 years. A total of 114 (38.9%) of the patients had an underlying medical condition. Asthma and chronic obstructive pulmonary disease were present in 44 (15.01%) of the patients, chronic cardiovascular diseases in 28 (9.56%), diabetes mellitus in 16 (5.46%), malignity in 15 (4.44%) of the patients and 11 (3.75%) of the patients were pregnant. Fever was registered in 282 (96.24%), myalgias in 119 (40.61%), headache in 48 (16.38%), cough in 240 (81.91%), sore throat in 25 (8.53%), runny nose and sneezing in 17 (5.8%) and dyspnea in 110 (37.54%) of the patients. A total of 192 (65.53%) had radiological findings that were consistent with pneumonia. A total of 154 (56.61%) of the patients received antiviral therapy within 48 h. A total of 280 (96.24%) patients were discharged and 13 (4.44%) were transferred to ICU. Fatal outcome was noticed in 2/13 (15.3%) ICU treated patients and 11/13 (84.7%) patients survived. The median time from the onset of illness to the initiation of antiviral treatment was 7.1 days for the patients admitted to ICU and 3.2 days for non-ICU patients (p < 0.05). Low blood oxygen saturation (SaO2 ? 92%) was more common in ICU admitted patients, 10/13 (76,92%), compared to 28/280 (10%) non-ICU admitted ones (p < 0.01). Serum C-reactive protein (CRP) levels > 200 mg/L were noticed in 9/13 (69.23%) patients admitted to ICU and 85/280 (30.35%) patients who were not (p < 0.05). Conclusion. Most novel influenza A (H1N1) 2009 infections presented mild respiratory disease. Prompt antiviral therapy in patients with A (H1N1) virus infection seem to be the best approach to avoid serious form of the disease. Special attention should be payed to patients having low level of peripheral oxygen saturation and raised CRP serum level.Uvod/Cilj. Infekcije uzrokovane virusom gripa A (H1N1) u vecini slucajeva manifestuju u blagom respiratornom simptomatologijom. Ipak, neki bolesnici zahtevaju hospitalizaciju u jedinicama intenzivne nege (intensive care units - ICU). Cilj rada bio je prikazivanje klinickih i laboratorijskih karakteristika bolesnika sa gripom A (H1N1) 2009, primenjene antivirusne terapije, ishoda bolesti i faktora rizika od razvoja teskog oblika bolesti. Metode. Studijom su bili obuhvaceni bolesnici sa znacima i simptomima pandemijskog gripa A (H1N1), hospitalizovani u Klinici za infektivne bolesti u Novom Sadu. Studijom je bilo obuhvaceno 293 bolesnika hospitalizovanih u periodu od oktobra 2009. do februara 2010. godine. Analizirani su osnovni demografski podaci, osnovne bolesti, znaci i simptomi gripa, trajanje simptoma do hospitalizacije, laboratorijske analize, radiografski nalaz, terapija i ishod bolesti (preziveli, umrli). Definisanje faktora rizika od tezeg oblika bolesti vrseno je uporedjivanjem karakteristika ICU bolesnika sa karakteristikama bolesnika koji nisu zahtevali hospitalizaciju u ICU. Rezultati. Prosecna starost bolesnika bila je 32,72 godine. Osnovne bolesti imalo je 114 (38,9%) bolesnika. Astma i hronicna opstruktivna bolest pluca registrovana je kod 44 (15,01%) bolesnika, hronicna kardiovaskularna oboljenja imalo je 28 (9,56%), secernu bolest 16 (5,46%), malignitet 15 (4,44%) bolesnika, a 11 (3,75%) bolesnika bile su trudnice. Povisena temperatura registrovana je kod 282 (96,24%), bolovi u misicima kod 119 (40,61%), glavobolja kod 48 (16,38%), kasalj kod 240 (81,91%), gusobolja kod 25 (8,53%), kijavica kod 17 (5,8%) i dispnea kod 110 (37,54%) bolesnika. Radioloski verifikovanu pneumoniju imalo je 192 (65,53%) bolesnika. Antivirusna terapija kod 154 (56,61%) bolesnika primenjena je u prvih 48 casova bolesti. Sa klinike je otpusteno 280 (96,24%) bolesnika, a 13 (4,44%) bolesnika je premesteno u ICU. Smrtni ishod zabelezen je kod 2/13 (15,3%) bolesnika lecenih u ICU, dok je 11/13 (84,7%) prezivelo. Prosecno vreme od pojave simptoma do primene antivirusne terapije iznosilo je 7,1 dana za bolesnike lecene u ICU, a 3,2 dana za bolesnike koji nisu bili hospitalizovani u ICU (p < 0,05). Hipoksemija sa saturacijom kiseonika SaO2 ? 92% registrovana je kod 10/13 (76,92%) bolesnika lecenih u ICU, i kod 28/280 (10%) koji nisu premesteni u ICU (p < 0,01). Vrednosti C-reaktivnog proteina (CRP) u serumu > 200 mg/L zabelezena su kod 9/13 (69,23%) bolesnika u ICU i kod 85/280 (30,35%) bolesnika bez transfera u ICU (p < 0,05). Zakljucak. Novi grip se ispoljava uglavnom kao blago respiratorno oboljenje. Rana primena antivirusne terapije moze spreciti razvoj tezih formi oboljenja. Posebnu paznju treba obratiti na bolesnike sa hipoksemijom i porastom vrednosti CRP u serumu.