Urinary antigene and PCR can both be used to detect Legionella pneumophila in children’s hospital-acquired pneumonia

Abstract

Legionella pneumophila is the causative agent of more than 95% cases of severe Legionella pneumonia. Nosocomial pneumonias in different hospital wards is an important medical and pharmaceutical concern. This study aimed to detect Legionella with two methods: polymerase chain reaction [PCR] and detection of urine antigenic test [UAT] in patients suffering from nosocomial pneumonia admitted to pediatric intensive care unit [PICU] of children hospitals. This study was conducted in PICU wards of Rasool Akram and Bahrami children hospitals, Tehran, Iran during 2013 - 2014. In patients diagnosed with hospital-acquired pneumonia, intratracheal secretion samples for PCR and urine sample for urinary antigen test [UTA] were taken. Simultaneously, PCR and urinary antigen test were conducted using commercial kits. The results of urinary antigen test and PCR were analyzed by SPSS v.19 for statistical comparison. In this study, 96 patients aging 2.77 years on average with two age peaks of less than 1 year and 7-8 year were enrolled. More than half of the patients were under 1 year old. The most common underlying diseases were seizure, Acute Lymphoblastic Lymphoma, Down syndrome and metabolic syndromes. The positivity rate of Legionella urinary antigen test was 16.7% and positivity rate of PCR test was 19.8%. There were no significant associations between the results obtained by both assays with age, gender or underlying diseases. In conclusion, PCR is a better detection method for Legionella infection than urinary antigen test, but the difference between the two methods was not significant.

Prevalence of Legionella pneumophila among patients suffering from pneumonia: a Middle East systematic review and meta-analysis

“…Their results were comparable with findings reported by some studies included in the present review like J.A. Qasem (2.9%) [20], Yasliani Fard (4.6%) [17], Agca (1.6%) [21] and Guldava (2.3%) [18], Sayed Zaki (5%) [13], but it is different from studies conducted by Yiallouros (28.1%) [12], Owayid Adday (18.5%) [14], Behbehani (8.1%) [15], Lina Jaber (22.6%) [16], Mojtahedi (19.8%) [8], Moosavian (7%) [19], Divan Khosroshahi (10.1%) [7], Nomanpour (7%) [25], and also with combined prevalence (8.5%) that we gained. In general, Legionnaire's disease knowledge and research about it are essential, and physicians must consider Legionnaire's disease in the differential diagnosis of pneumonia (Table 2).…”

“…In general, 58.8 and 41.2% of patients were male and female, respectively (Table 1). Phenotyping methods included culture on BCYE medium [7,[12][13][14][15][16][17], serological tests (direct immunofluorescence [12], determination of IgM titer [ELISA] kit [13], IgM and IgG (EIA kits) [15,18], urine antigenic test [UAT]) [8] and molecular techniques: nested PCR sequence-based typing (NPSBT) [16], PCR of mip gene [17,19] and LAMP [19], RAPD-PCR [20], real-time PCR of 16s rRNA gene [7,8].…”

“…It is important to note that the most susceptible people are children younger than 2 years, elderly and immunodeficiency individuals that they are at the highest risk of infection [7]. L. pneumonia simultaneously has been seen in both sporadic and epidemic forms, where coinfection of Legionella with causative agents of respiratory infections including Streptococcus pneumonia, Haemophilus influenza and Mycobacterium tuberculosis can cause to further complicated health concerns [8]. Patients with normal immune system with Legionella infections do not have a specific complication and are treated if they timely diagnosed and treated.…”

Whole-genome sequencing of the clinical isolate of Legionella pneumophila ALAW1 from the West Bank allows high-resolution typing and determination of pathogenicity mechanisms

“…The contamination of hospital water systems with L. pneumophila is considered to pose a high risk for patients, especially for vulnerable and immunocompromised people. To this end, it is well known that LD is an important cause of hospital-acquired pneumonia [ 9 ]. The presence of L. pneumophila in DWDS could be a serious health risk to hospital staff and patients, but the magnitude of the problem is often unrecognized [ 1 , 9 ].…”

Occurrence of the Legionella species in the respiratory samples of patients with pneumonia symptoms from Ahvaz, Iran; first detection of Legionella cherrii

“…The global occurrence of LD remains unknown in many countries due to the lack of efficient diagnostic and monitoring systems, but its burden in the United States and European countries shows an incremental chart each year [5,6]. Around 1-30% of hospital-acquired pneumonia (CAP) cases are caused by Legionella species [7]. In the recent systematic review and meta-analysis performed by Khaledi et al [8)], the frequency of the Legionella pneumophila, the main cause of LD disease, was estimated as 0.4-22.1% in Iran.…”