ABSTRACT
The diagnosis and clinical management of lower respiratory tract infections [LRTI] pose challenges to pediatricians as new technology is developed and new pathogens emerge in the spectrum of clinical diagnosis. This study aimed at rapid diagnosis of atypical lower respiratory tract infections in pediatric patients using Pneumoslide- M test. This study included 55 children with acute LRTI [pneumonia,bronchiolitis and croup[their age ranged from > one month to < two years with the mean age of [12.8 +/- 3.7]. All cases were subjected to complete history taking, thorough clinical examination and laboratory tests which included: Complete blood count, nasopharyngeal aspirates smear and culture. According to the microbiological results the studied patients were classified into two groups: Group I: The caustive pathogen was detected by the conventional microbiological methods,this includes 31 children and Group II: In which the caustive pathogen was not identified by the conventional microbiological methods [Atypical lower respiratory tract infections],this includes 24 children.Cases of group II only were subjected to Pneumoslide-M test. [Indirect immunofluorescence test for detection of serum IgM against respiratory viruses and atypical bacteria]. Pneumoslide M test could identify the causative pathogen in 91.7% [22 out of 24 cases] of group II patients and the diagnosis was as follows: respiratory syncytial virus [RSV] infection in 9 cases [37.5%], parainfluenza viruses [PIV] infection in 5 cases [20.8%], adenovirus infection in 4 cases [16.7%], influenza A virus infection in 3 cases [12.5%]. M. pneumonia infection was detected in only one case [4.2%] and 2 cases [8.3%] remained undiagnosed . Viruses and atypical bacteria constitute almost 43.6% of the causative agents of LRTI in young children especially in winter times. The use of Pneumoslide M test has great value in rapid diagnosis of this infection
Subject(s)
Humans , Male , Female , Child , Fluorescent Antibody Technique/methods , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/virologyABSTRACT
Methicillin resistant Staphylococcus aureus [MRSA] is an important pathogen causing severe nosocomial infections whose prevalence has been increasing. The effectiveness of infection control measures is enhanced by early detection of resistant isolates and this is dependent on the time taken to isolate and identify MRSA In specimens taken from infected patients and in screening specimens taken to identify patients colonized with MRSA. So we aimed in this study to evaluate the abilities of phenotypic methods [Disk diffusion. E-test and Latex agglutination test] and genotypic method [real time PCR] for rapid detection of methicillin resistance in S. aureus. It was done on 220 patients [155 males and 65 females] at Benha University Hospital during the period from March to September 2005 to isolate any growth of S. aureus. Two hundred and twenty clinical samples were collected: they were 140 pus samples. 48 urine samples and 32 blood samples. Pus and urine samples and positive blood cultures were cultured to isolate any growth of S. aureus then the isolated colonies were examined for identification of MRSA isolates by disk diffusion method [Ox 1 micro g. Ox 5 micro g and Fox 30 micro g]. E-test. PBP2a latex agglutination test and detection of mecA gene by real time PCR. Two hundred isolates were detected in 220 clinical samples The frequency of S. aureus isolates was 28% [56 out of 200 isolates] they were mainly from wound pus [36 out of 56] The mec A PCR assay allowed us to classify 22[39.3%] of the isolates as S. aureus mec A-positive and they were mainly from pus [12 out of 22] and blood [6 out of 22]. and 34 [60.7%] as S aureus mecA negative. When phenotypic and genotypic identification was compared with PCR results it was found that by oxacillin 1 micro g disk, the sensitivity was 90.9% and the specificity was 94.1% by oxacillin 5 micro g disk, the sensitivity was 90.1% and the specificity was 76.5%, while cefoxittin 30 micro g disk yield 100% sensitivity and 94.1% specificity. Oxacillin E-test strips had the same sensitivity and specificity of oxacillin lmicrog disk. Latex agglutination test and real time PCR had the best sensitivity[100%] and specificity [100%] and they are able rapidly and reliably to detect MRSA isolates. the new molecular assay [real time PCR] was found to be rapid and robust because it is a largely automated assay. less hands on work is needed, consumes shorter time than conventional PCR and it can be used for direct detection of MRSA from non sterile clinical specimen, however, it is not yet available in the majority of routine diagnostic laboratories because of their elevated technical requirements. In absence of real time PCR. latex agglutination test is the best method for MRSA detection from isolated colonies