Acinetobacter baumannii bacteraemia in patients with haematological malignancy: a multicentre retrospective study from the Infection Working Party of Jiangsu Society of Hematology

Abstract

Acinetobacter baumannii (Ab) bacteraemia in patients with haematological malignancies is fatal but rarely reported. We explored the clinical characteristics, drug resistances and prognostic factors in these patients. This multicentre, retrospective study was conducted at the department of haematology wards of 18 tertiary hospitals in China from January 2014 to June 2015. The total clinical isolates from every source were collected from patients with haematological malignancy. Haematological malignancy patients diagnosed with Ab bacteraemia were analysed. During the study period, 40 patients with Ab bacteraemia were identified, accounting for 2.9% (40/1358) of bacteraemia cases, of which 25 (62.5%) had acute leukaemia (AL) and 27 (67.5%) had neutropaenia. Compared with non-neutropaenic patients, neutropaenic patients showed higher Acute Physiology and Chronic Health Evaluation (APACHE) scores and 30-day mortality rates (p < 0.05). The in vitro antibiotic susceptibility of Ab to colistin was highest, at 100%, followed by that of tigecycline (91.30%) and amikacin (75.86%). Compared with the patients who had carbapenem-susceptible Ab infections, patients infected with carbapenem-resistant Ab (CRAB) had significantly longer hospital stays and were more likely to have had exposure to carbapenem before bacteraemia (p < 0.05). The 30-day mortality rate was 32.5%. CRAB, neutropaenia, higher APACHE score, Pitt bacteraemia score and inappropriate initial antimicrobial therapy were significantly associated with 30-day mortality. Multivariable analysis showed that APACHE score and CRAB were independent predictors of 30-day mortality. Haematologic patients with AL and febrile neutropaenia were at high risk of Ab bacteraemia. More attention should be paid to CRAB, which is an independent risk factor for mortality in haematological malignancy patients with Ab bacteraemia.

Detection of acquired carbapenemase genes among Acinetobacter baumannii isolated from blood culture in patients with hematological malignancies

“…В проведенном нами исследовании нечувствитель ность к карбапенемам была выявлена у 74,3% изолятов A. baumannii. По результатам ряда других исследова ний, посвященных изучению A. baumannii, выделенных из гемокультуры больных гемобластозами, доля кар бапенемонечувствительных изолятов варьировала от 36,1% [5] до 100% [6]. О различиях в уровне устой чивости к карбапенемам сообщалось и среди изолятов A. baumannii, выделенных в многопрофильных стацио нарах.…”

“…Согласно результатам ряда исследо ваний, в России доля A. baumannii, выделенных из гемо культуры больных опухолями системы крови, составляет 3-4% [2][3][4]. По данным литературы, этот показатель ва рьируется от 2,9% до 6% [5,6], а у реципиентов гемо поэтических стволовых клеток достигает 11,8% [7]. По результатам российского многоцентрового эпидемио логического исследования антибиотикорезистентности возбудителей нозокомиальных инфекций «МАРАФОН», проведенного в 2013-2014 гг., в многопрофильных ста ционарах доля A. baumannii составила 13,7% от всех вы деленных бактериальных изолятов [8].…”

“…В исследовании, проведенном в Беларуси, доля карбапенеморезистентных изолятов среди A. baumannii, вызывающих инфекции кровотока у реци пиентов гемопоэтических стволовых клеток, составила 75% (12/16 изолятов) [7]. Кроме того, выделение рези стентных к карбапенемам изолятов A. baumannii из гемо культуры являлось фактором риска летального исхода в течение 30 дней у больных опухолями системы крови [5,7]. О высоком уровне устойчивости к карбапенемам со общается также и у A. baumannii, выделенных в много профильных стационарах.…”

Comparison of clinical characteristics and outcomes of bloodstream infections due to multidrug-resistant Acinetobacter baumannii and other Gram-negative bacteria in ICU patients

“…It is well known that ICU is a very common place to contract an infection, especially from A. baumannii, which mainly includes the following two reasons. As regard patient's factors: long hospital stay [5], experience of invasive procedures (CVC [35], surgery [1,36], mechanical ventilation [37]), exposure to antibiotics [1,36] such as carbapenems, weak immunity (previous hormone therapy [36], tumor patients with neutropenia [38]). As regard the contamination of wards [39] A. baumannii is a bacterium commonly present in ICU that is difficult to eliminate and it often spreads among the ward crowd, resulting in a high risk of A. baumannii colonization for patients [40,41].…”

“…Overall, previous studies found that the prognosis of A. baumannii BSI in ICU patients is different depending on the underlying disease, illness severity, drug resistance, therapies used, post-infection appearance and infection source. The following characteristics often lead to poor prognosis: improper initial antibiotic treatment [9,38], comorbidities (tumours [38,44,45], liver cirrhosis [46], chronic obstructive pulmonary disease and chronic renal failure [37]), high drug resistance, neutropenia [38], previous high-dose hormone therapy [47], previous surgery [9], infection originated from the respiratory tract [35,46], high SAPS score [8], Pitt score [35], APACHE II score [37,38,46]. However, the development of septic shock [47] and the severity of the disease are the factors most closely related to prognosis, and our study also found these two key points.…”