Risk factors for nosocomial Acinetobacter bacteremia: a case-control study of intensive care unit patients

Abstract

Objective: This study was performed to identify risk factors and to determine the attributable mortality and clinical outcomes of nosocomial Acinetobacter bacteremia in our intensive care unit. Methods: A retrospective case-control (1:1) study was conducted in a tertiary, academic hospital composed of 300 beds. The control group consisted of 54 consecutive patients with negative blood cultures, matched by sex, age (&plusmn;10 years), primary and secondary diagnosis, operative procedures, and date of admission. Results: There was a trend for a longer median duration of hospitalization among the patient group compared with the control group (25.0 versus 8.0 days; p=0.001). Patients with Acinetobacter bacteremia had significantly more hemodynamic instability (hypoxia, shock) (p=0.001). We detected that the presence of risk factors such as mechanical ventilation, central venous catheter, anemia, thrombocytopenia, hypoalbuminemia and impairment in creatinine clearance was higher in the patient group than in the control group (p<0.004). Thirty-three (61.1%) of the cases died whereas 14 (25.9%) of the controls died (p=0.001). The attributable mortality was estimated as 35.2%. Of the 54 Acinetobacter isolates, 44 (81.5%) were resistant to two or more different antibiotic classes. Conclusion: In critically ill patients, Acinetobacter bacteremia is associated with a significantly increased mortality rate. Central venous catheter insertion, mechanical ventilation, long length of hospital stay and concomitant metabolic disease were risk factors for the presence of bacteremia.

Keywords

• Acinetobacter spp., intensive care unit, nosocomial bacteremia

Risk factors for nosocomial Acinetobacter bacteremia: a case-control study of intensive care unit patients

Öz

Amaç: Bu çalışma yoğun bakımda gelişen hastane kökenli Acinetobacter bakteriyemilerinde risk faktörlerinin belirlenmesi, hastalığın klinik sonuçlarının ve bakteriyemiye atfedilen mortalitenin saptanması için yapıldı.Yöntemler: Çalışma, 300 yataklı üçüncü basamak bir üniversite hastanesinde retrospektif vaka kontrollü (1:1) olarak gerçekleştirildi. Kontrol grubu; kan kültürü negatif, yaş (± 10), cins, birincil ve ikincil tanıları, operasyon öyküleri ve başvuru zamanları vaka grubu ile eşleşen 54 ardışık hastadan oluşturuldu.Bulgular: Hasta grubunda ortalama yatış süresi kontrol grubuna göre uzundu (sırasıyla 25.0 ve 8,0 gün, p=0,001). Acinetobacter bakteriyemisi olan hastalarda hemodinamik instabilite (hipoksi, şok) daha sık gözlendi (p=0,001). Mekanik ventilasyon, santral venöz kateterizasyon, anemi, trombositopeni, hipoalbüminemi ve kreatinin klirensinde bozulma gibi risk faktörleri hasta grubunda kontrol grubuna göre fazlaydı (p<0,004). Kontrol grubunda 14 (% 25,9) hasta kaybedilirken, hasta grubunda bu sayı 33 (% 61,1) olarak bulundu (p=0.001). Atfedilen mortalite % 35,2 olarak hesaplandı. Ellidört Acinetobacter izolatının 44’ü (% 81,5) iki ve daha fazla antibiyotik grubuna dirençliydi.Sonuçlar: Acinetobacter bakteriyemisi özellikle kritik hastalarda mortaliteyi belirgin olarak arttırmaktadır. Santral venöz kateter varlığı, mekanik ventilasyon, uzun hastanede yatış süresi, eşlik eden metabolik hastalıklar bakteriyemi için risk faktörleridir

Anahtar Kelimeler

• Acinetobacter spp., yoğun bakım ünitesi, hastane kökenli bakteriyemi

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