Mohammadi-Ghalehbin Behnam, Habibzadeh Shahram, Arzanlou Mohsen, Teimourpour Roghayeh, Amani Ghayum Saeideh
Dept. of Microbiology and Medical Parasitology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.
Dept. of Infectious Diseases, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.
Iran J Pathol. 2018 Spring;13(2):136-143. Epub 2018 Jul 17.
BACKGROUND & OBJECTIVE: pneumonia (PCP) is responsible for pulmonary infection in immunocompromised patients. The current study aimed at investigating the frequency of colonization in patients hospitalized in the intensive care unit (ICU) and evaluating the relationship between PCP and colonization.
The current cross sectional study was conducted on bronchoalveolar lavage (BAL) fluids of 100patients collected from surgery and neurosurgery ICUs with different underlying corticosteroid therapy conditions. Patients were divided into 2 groups (patients receiving and not receiving corticosteroids). Direct examination on BAL fluids was performed by the Gomori methenamine silver and Giemsa staining techniques. Additionally, 2 filtered air samples of the 2 above mentioned units were collected. A nested-PCR targeted mtLSUrRNA gene and sequencing were used to identify spp.
In direct microscopy, 31 out of 100 hospitalized patients (31%) showed positive results. Twenty-three (46%) of smear positive patients were from the group of patients receiving corticosteroid, the other 8(16%) were from the group of patients not receiving corticosteroids (= 0.001). DNA was detected in 77 out of 100 BAL samples by nested-PCR (77%) in which 40 (52%) and 37 (48%) samples were obtained from the patients receiving and not receiving corticosteroids, respectively. Pneumocystis genome was observed in 1 of the 2 filtered air samples.
A significant number of patients receiving corticosteroids were also colonized by that may be predisposed to PCP or be transmitted to susceptible patients. A significant relationship was observed between the mean hospital stay and detection rate.
肺孢子菌肺炎（PCP）是免疫功能低下患者肺部感染的病因。本研究旨在调查重症监护病房（ICU）住院患者的肺孢子菌定植频率，并评估PCP与定植之间的关系。
本横断面研究对100例患者的支气管肺泡灌洗（BAL）液进行了检测，这些患者来自外科和神经外科ICU，具有不同的潜在皮质类固醇治疗情况。患者分为2组（接受和未接受皮质类固醇治疗的患者）。采用吉姆萨染色技术和Gomori六胺银染色技术对BAL液进行直接检查。此外，还收集了上述两个科室的2份过滤空气样本。采用靶向mtLSUrRNA基因的巢式PCR和测序技术鉴定肺孢子菌属。
在直接显微镜检查中，100例住院患者中有31例（31%）结果呈阳性。涂片阳性患者中有23例（46%）来自接受皮质类固醇治疗的患者组，另外8例（16%）来自未接受皮质类固醇治疗的患者组（P=0.001）。通过巢式PCR在100份BAL样本中的77份（77%）中检测到肺孢子菌DNA，其中分别有40份（52%）和37份（48%）样本来自接受和未接受皮质类固醇治疗的患者。在2份过滤空气样本中的1份中观察到肺孢子菌基因组。
大量接受皮质类固醇治疗的患者也被肺孢子菌定植，这可能使他们易患PCP或传染给易感患者。观察到平均住院时间与检出率之间存在显著关系。
