فهرست مطالب

Archives of Pediatric Infectious Diseases - Volume:5 Issue: 2, 2017 Apr

Archives of Pediatric Infectious Diseases
Volume:5 Issue: 2, 2017 Apr

  • تاریخ انتشار: 1396/01/06
  • تعداد عناوین: 14
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  • Pejman Abbasi, Mohammad Kargar*, Abbas Doosti, Jalal Mardaneh, Sadegh Ghorbani Dalini, Mohammad Ali Dehyadegari Page 1
    Background
    Diarrhea continues to be one of the most common causes of morbidity and mortality among children in developing countries. Recently, some studies have implicated diffusely adherent Escherichia coli (DAEC) strains as a cause of diarrhea. The clinical manifestations of diarrhea caused by DAEC strains may include watery or bloody diarrhea, abdominal pain, dehydration, and fever.
    Objectives
    The aims of this study were (1) isolation of E. coli from fecal samples obtained from patients with diarrhea in Shiraz (Iran), (2) detection of DAEC pathotypes in isolates by molecular diagnostic techniques such as conventional PCR and real-time PCR assays, and (3) investigation of the antibiotic susceptibility of DAEC isolates.
    Materials And Methods
    Seven hundred and fifteen stool specimens of diarrhea patients were collected in Shiraz, Fars, Iran. Diarrheagenic E. coli strains were isolated by standard biochemical analysis. Susceptibility testing was performed by the diffusion method, according to the guidelines of the Clinical and Laboratory Standards Institute. Real-time PCR and conventional PCR were used to detect the daaD gene in the DAEC strains isolated.
    Results
    Of the 715 stool samples tested, 101 (14.1%) were identified as E. coli by biochemical tests and culture. Of the infected patients, 58 (57%) were male and 43 (43%) were female, with a mean age of 13.52 (SD, 1.66) years. Eight of the E. coli strains were identified as DAEC strains. The most effective antibiotics against the DAEC isolated were levofloxacin and imipenem, and the least effective antibiotics were ampicillin and penicillin.
    Conclusions
    Our analysis indicated that DAEC strains may be considered as potential pathogens in Shiraz, southern Iran. Further, although the prevalence of DAEC is low, prevention of infection caused by this bacterium among asymptomatic patients is crucial. Therefore, further characterization of the different virulence aspects of DAEC strains is required.
    Keywords: Diarrhea, Diffusely Adherent E. coli (DAEC), Children, Real-time PCR
  • Alka Hasani, Ali Purmohammad*, Mohammad Ahangarzadeh Rezaee, Akbar Hasani, Masoud Dadashi Page 2
    Background
    Despite intensive care and treatment strategies, the development of antibiotic resistance to empirical drugs is concerning.
    Objectives
    The aim of this study was to characterize extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae for integron-mediated quinolone resistance and multidrug resistance (MDR).
    Methods
    In this cross-sectional study, 71 E. coli and 63 K. pneumoniae clinical isolates underwent antibiotic susceptibility testing with the Kirby-Bauer method, followed by ESBL phenotypic screening with the combination disc method. The isolates were then genotypically characterized with PCR for the presence of integrons and the gyrA, parC, blaCTX-M-3, blaTEM, and blaSHV genes. Resistance to antibiotics was confirmed by sequencing.
    Results
    K. pneumoniae was a potent ESBL producer (71.4%) in comparison to E. coli (57.7%). The predominant ESBL genotypes in E. coli and K. pneumoniae confirmed by sequencing were blaCTX-M-15 (67.60%) and blaSHV-1 (80.95%), respectively. Imipenem was the only antibiotic active against the ESBL-producing isolates. Approximately 54% of the isolates exhibited MDR patterns. MDR was more frequently related to the presence of blaCTX-M-3 in comparison to other genotypes. The prevalence of class 1 integrons was 15 (45.4%) and 22 (66.6%) of the E. coli and K. pneumonia isolates, respectively. Within the ESBL group, a class 1 genetic element was associated with the blaCTX-M-3 genotype in E. coli (36.58%) and K. pneumoniae (51.11%). Overall, almost half of the ESBL producers, irrespective of genus, were simultaneously resistant to quinolones. The simultaneous presence of class 1 and 2 integrons in quinolone-resistant isolates was the most frequent observation.
    Conclusions
    The high prevalence of multidrug and ESBL-mediated resistance is a therapeutic concern. The co-emergence of ESBLs and quinolone resistance in E. coli and K. pneumoniae suggests the preservation of the power of antibiotics in the face of the antibiotic-resistance crisis.
    Keywords: Drug Resistance, Extended-Spectrum β-Lactamase, Quinolones, Klebsiella pneumoniae, Escherichia coli
  • Fariba Mohammadi, Hossein Goudarzi*, Ali Hashemi, Neda Yousefi Nojookambari, Saeed Khoshnood, Fattaneh Sabzehali Page 3
    Background
    The presence of carbapenemase-producing Acinetobacter baumannii has become a growing concern in patients who are hospitalized in burns centers.
    Objectives
    The aims of this study were to determine the antimicrobial susceptibility patterns and prevalence of blaOXA carbapenemases, as well as to detect the presence of ISAba1, in A. baumannii strains carrying OXA genes obtained from burns patients at Shahid Motahari hospital, Tehran, Iran.
    Methods
    From August 2013 to March 2014, 100 clinical A. baumannii isolates were collected from patients who were admitted to the burns ward at Shahid Motahari hospital. Antimicrobial susceptibility was determined using a disc diffusion test. PCR, sequencing, and multiplex PCR were used for the detection of blaOXA-23-like, blaOXA-51-like, blaOXA-24-like, and blaOXA-58-like genes, which were then sequenced. The ISAba1 gene was detected, and PCR was performed to detect the presence of ISAba1/blaOXA-51-like and ISAba1/blaOXA-23-like genes.
    Results
    The results showed that 93% of the strains were multi-drug resistant, while 82% of them were extensively drug resistant. Additionally, all the strains carried blaOXA-23-like and blaOXA-51-like genes, while 74% and 0% of the strains harbored blaOXA-24-like and blaOXA-58 genes, respectively. ISAba1 was detected in all the strains except for one. The co-existence of ISAba1/blaOXA-51-like genes and ISAba1/blaOXA-23-like genes was detected in 65% and 80% of strains, respectively.
    Conclusions
    The results of this study indicate that the emergence of OXA-type carbapenemases in A. baumannii causing nosocomial infections in burns patients could be of importance for hospital infection control systems in Iran.
    Keywords: Carbapenemase, Isaba1, Multi, Drug Resistance, Extensively Drug Resistance, Burn, Acinetobacter baumannii
  • Reza Ranjbar, Hamed Memariani*, Rahim Sorouri Page 4
    Background
    Uropathogenic Escherichia coli (UPEC) and Klebsiella pneumoniae (K. pneumoniae) are major pathogens which cause urinary tract infections (UTI) in pediatric patients. The presence of extended-spectrum β-lactamases (ESBLs) in these pathogens may further exacerbate infections and hamper successful treatment.
    Objectives
    We undertook a study to investigate the prevalence of ESBL genetic indicators among K. pneumoniae strains isolated from pediatric patients in Tehran, Iran. Moreover, genotyping of blaCTX-M-15-positive isolates was determined through repetitive extragenic palindromic sequence polymerase chain reactions (REP-PCR).
    Methods
    A total of 76 non-duplicate K. pneumoniae isolates were collected from outpatients admitted with UTIs at the pediatric nephrology wards of two hospitals in Tehran, Iran. The antibacterial susceptibility of K. pneumoniae isolates was determined by the disk diffusion method. The isolates were examined phenotypically and genotypically for ESBL production using the combined-disk method and PCR, respectively. The blaCTX-M-positive isolates were subjected to minimal inhibitory concentration (MIC) testing for ceftazidime and cefotaxime. The clonal relationships of blaCTX-M-15-positive isolates were determined through REP-PCR.
    Results
    The highest rates of antibiotic resistance were obtained for ampicillin (92.1%), followed by ceftazidime (40.8%), cefotaxime (40.8%), and aztreonam (39.5%). However, only one isolate (1.3%) was resistant to imipenem. Among the ESBL-positive isolates, blaCTX-M(64.5%) was the most prevalent gene, followed by blaSHV (54.8%) and blaTEM (41.9%). Of 20 blaCTX-M-carrying isolates, 14 isolates showed MICs of 256 μg/mL against cefotaxime. The other six isolates had MICs of 512 μg/mL. However, 16 out of 20 blaCTX-M-carrying isolates exhibited MICs of 128 μg/mL against ceftazidime. The other four K. pneumoniae isolates showed MICs of 256 μg/mL. Of 17 blaCTX-M-15-positive K. pneumoniae isolates, 16 distinct REP-PCR patterns (genotypes) were obtained..
    Conclusions
    The frequency of blaCTX-Mamong K. pneumoniae isolates was at an alarming rate, indicating that more efforts should be undertaken to track and monitor the spread of K. pneumoniae that produce CTX-M β-lactamases.
    Keywords: Urinary Tract Infections, Pediatric, Extended, Spectrum β, Lactamases, Klebsiella pneumoniae
  • Maryam Koshesh, Shahla Mansouri, Zahra Hashemizadeh, Davood Kalantar Neyestanaki* Page 5
    Background
    Escherichia coli is the main causative pathogen in urinary tract infections (UTIs). Antibiotic resistance in this bacterium is an important problem in public health.
    Objectives
    The aim of this study was to identify the blaTEM, blaSHV, blaOXA, and blaPER genes and AmpC-β-lactamase in clinical isolates of E. coli recovered from patients with UTIs in Kerman, Iran.
    Methods
    E. coli isolates (N = 105) were analyzed for their antibiotic susceptibility with the disk diffusion method. ESBL and AmpC-producing isolates were detected using phenotypic methods. PCR was used to identify the blaTEM, blaSHV, blaOXA and blaPER genes in ESBL and AmpC-positive isolates.
    Results
    More than 50% of the isolates were multi-drug resistant. The prevalence of ESBLs, AmpC-β-lactamase, blaTEM and blaOXA in the inpatient isolates was 37.2%, 2%, 37.2% and 5.8%, respectively. Further, the prevalence of ESBLs, blaTEM, blaSHV and blaOXA in the outpatient isolates was 42.5%, 24%, 5.5% and 1.8%, respectively.
    Conclusions
    The prevalence of ESBL-producing E. coli strains in the community (outpatients) is higher than that in inpatients in Kerman, Iran. An outbreak of ESBL-producing isolates in the community can be a serious problem for public health, as resistance to other classes of antibiotics such as aminoglycoside and fluoroquinolones is often related with ESBL and AmpC production, therefore, detection of ESBL and AmpC-producing isolates in the community and hospitals is very important for the treatment and prevention of such isolates.
    Keywords: Escherichia coli, MDR, ESBLs, AmpC
  • Shahin Najar Peerayeh, Safoura Derakhshan *, Fatemeh Fallah, Bita Bakhshi Page 6
    Background

    Extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae is rapidly spreading worldwide, creating serious problems in clinical settings.

    Objectives

    The aim of this study was to describe the molecular and epidemiological characteristics of CTX-M-1 group ESBL-producing K. pneumoniae.

    Methods

    Seventeen CTX-M-1 group ESBL-producing K. pneumoniae isolates found among 31 K. pneumoniae isolates in samples collected from three hospitals in Tehran, Iran between May and December 2011 were included in the present study for further characterization and determination of clonal relationships. The genetic environment of blaCTX-M-1 was analyzed by polymerase chain reaction (PCR) mapping and sequencing, and the transferability of blaCTX-M-1 was evaluated through the use of a conjugation assay. PCR-based replicon typing (PBRT) was used to identify plasmid replicons. The isolates were typed using pulsed-field gel electrophoresis (PFGE).

    Results

    All 17 isolates carried the blaCTX-M-15 gene. IncL/M was the most common replicon type (82.3%). The conjugation experiment showed that blaCTX-M-15 was carried on transferable plasmids. In all of the studied isolates, the mobile element ISEcp1 was found upstream and orf477 downstream of blaCTX-M-15, whereas IS26 was not found. PFGE identified 11 different profiles and one major clone.

    Conclusions

    The findings of this study suggest that among the K. pneumoniae strains isolated from samples of children, dissemination of the blaCTX-M-15 gene is due to clonal spread and to the dissemination of mobile genetic elements bearing blaCTX-M-15, such as ISEcp1. Genotyping of K. pneumoniae is indispensable for monitoring the spread of ESBL-producing strains, for initiating the implementation of suitable infection control measures, and for general epidemiology purposes.

    Keywords: Klebsiella pneumoniae, CTX-M-15 β-lactamase, Children, Genotyping
  • Mojtaba Anvarinejad, Gholamreza Pouladfar, Aziz Japoni, Shahram Bolandparvaz, Zeinab Satiary, Jalal Mardaneh* Page 7
    Background
    Diabetic foot infections (DFIs) are an increasingly common public health problem and are associated with mortality and morbidity. The incidence of Enterococci in DFIs, a leading cause of hospital admission in Iran, has been increasing, possibly due to previous antibiotic use.
    Objectives
    The aims of this study were 1) isolation of bacteria from diabetic patients with foot ulceration, 2) characterization of the isolated bacteria, 3) confirmation of Enterococci and their genus, 4) determination of the susceptibility profile of the isolates, and 5) survey of the cross-resistance among Enterococcus spp.
    Methods
    A total of 86 diabetic patients with foot ulceration were investigated during 2012 - 2014 in Nemazee hospital (Shiraz, Iran). Swabs were collected from diabetic ulcers. For the isolation of bacteria, microbiological media were used. Colonies were further characterized using various biochemical tests (e.g., catalase test, oxidase reaction, growth on bile esculine [BE] agar, growth in the presence of 6.5% NaCl, growth at 45°C, motility, pyrrolidonyl arylamidase [PYR], yellow pigment, arginine dihydrolase [ADH], and sugars fermentation). Antibiotic susceptibility testing was done by standard disc diffusion method, according to the CLSI protocols. Detection of vancomycin-resistant Enterococcus (VRE) was performed by BHI agar screen plate.
    Results
    In the current study, a total of 86 diabetic patients were investigated. Enterococcus spp. were isolated from 34 (39.5%) patients consisting of 20 males (59%) and 14 females (41%). Twenty-five (73.5%) patients received antibiotic treatment on admission. Fifty (44.1%) cases had random blood sugar ranging between 130 - 300, and 19 (55.9%) had blood sugar of 300 - 450. Of the 34 patients, 15 (44.1%) had type 1 diabetes and 19 (55.9%) had type 2 diabetes. Enterococcus faecalis was the most common isolated Enterococcus spp. (50%). Linezolid was the most effective antibiotic against Enterococcus isolates, and ciprofloxacin was the least effective.
    Conclusions
    Our data showed that resistance to vancomycin among Enterococcus spp. isolates is emerging. Knowledge of the causative microorganisms in DFIs and their antibiotic susceptibility profiles is essential for proper treatment and infection eradication.
    Keywords: Enterococcus spp., Diabetic Foot Infections, Antibiotic Susceptibility, Antibiotic Cross-Resistance
  • Mitra Radfar, Minoo Fallahi*, Mohammad Kazemian, Samira Borhani Page 8
    Background
    Sepsis is one of the most common causes of neonatal mortality and morbidity in NICUs. Prescription of broad-spectrum antibiotics is increasing; hence, increase in antibiotic resistance is a concern. Information about changing microbial patterns and antimicrobial sensitivity over time helps us to choose the most appropriate antibiotics.
    Objectives
    The aim of this research was to assess the changing microbial patterns and antibiotic susceptibility during a 23-year interval from 1992 to 2015 in the NICU of the Mofid Children’s hospital in Tehran, Iran.
    Methods
    We conducted a retrospective comparative descriptive study between 1992 and 2015. Neonates with positive blood cultures were enrolled, and the microbial characteristics and antibiograms of the blood cultures were compared.
    Results
    One-hundred cases of positive blood cultures in 1992 and 103 cases in 2015 were analyzed and compared. Overall, 57% of neonates were male and 43% were female; 56% of the sepsis was late onset and 44% was early onset; 63% of neonates had term gestation and 37% were preterm. We found that the most common causes of positive blood culture isolated in 1992 were Staphylococcus aureus (59%) and Staphylococcus epidermidis (40.9%). In 2015, the most common causes were (coagulase negative staphylococci) CONS (33.98%) and Pseudomonas aeruginosa (20.3%). In the evaluation of antibiograms, the rate of resistance to cephalosporins, aminoglycosides (except tobramycin), and oxacillins increased from 1992 to 2015. In 2015, the sensitivity rate to imipenem, meropenem, ciprofloxacillin, vancomycin, and linezolid was greater than the resistance, whereas to piperacillin, colistin, and cefepim, and cefotaxim, the rate of resistance was higher. In the evaluation of antibiotic sensitivity based on microorganisms in 2015, piperacillin had the highest effectiveness against pseudomonas and Klebsiella, with no effectiveness against Acinetobacter. Ciprofloxacin had the highest effectiveness against E. coli and Klebsiella. One-hundred percent of Streptococci, 83.3% of Staphylococcus aureus, and 71.4% of coagulase negative Staphylococci were sensitive to vancomycin.
    Conclusions
    In this research, we found that the pattern of microbial and antibiotic sensitivity has changed, and overall antibiotic resistance is increasing. This is an indication that healthcare providers should use broad-spectrum antibiotics with caution.
    Keywords: Antibiotics Antibiogram, Neonates, Sensitivity, Sepsis
  • Abolfazl Mahyar, Parviz Ayazi, Marjan Abbasi, Reza Dalirani*, Alireza Taremiha, Amir Javadi, Shiva Esmaeily Page 9
    Background
    According to some reports, 25-hydroxy vitamin D (25 (OH) D) deficiency leads to respiratory diseases. Given the high prevalence of acute bronchiolitis in young infants, the assessment of 25 (OH) D status is very important for this disease.
    Objectives
    This study was conducted to determine the relationship between the serum levels of 25 (OH) D and acute bronchiolitis in young infants.
    Methods
    In the present study, 57 patients with acute bronchiolitis (case control) were compared with 57 healthy children (control group) in terms of 25 (OH) D serum levels. The serum levels of 25 (OH) D were measured using the ELISA method. The results were analyzed and compared between the two groups.
    Results
    The mean and standard deviation of 25 (OH) D serum levels were 26 ± 9.5 and 23.3 ± 8.3 ng/mL in the case and control groups, respectively. No significant difference was observed between the two groups in terms of 25 (OH) D serum levels (P = 0.11).
    Conclusions
    This study showed that there is no significant difference between children with acute bronchiolitis and normal children in terms of serum 25 (OH) D levels. It therefore seems that 25 (OH) D does not play any role in the pathogenesis of acute bronchiolitis. Further studies in this area are recommended.
    Keywords: Acute Bronchiolitis, 25-Hydroxy Vitamin D
  • Doaa Mahdy El Wakil, Eman Ahmed El Seidi, Reham Aly Dwedar, Lamiaa Abd El Fattah Madkour*, Hanaa Ibrahim Rady Page 10
    Background
    Estimated as the second or third most prevalent respiratory pathogen in the pediatric population, routine testing for human metapneumovirus (hMPV) can have a pivotal impact on children’s clinical outcome.
    Objectives
    This cross-sectional analytical study aimed to determine the efficiency of direct fluorescent antibody (DFA) assay as a rapid tool for the diagnosis of hMPV infection as compared to real time reverse transcriptase polymerase chain reaction (rRT-PCR). In the meantime, we endeavored to analyze the clinical features in hMPV patients.
    Methods
    A total of 50 children aged ≤ 24 months presenting with manifestations of acute respiratory tract infection (ARTI) at El-Mounira pediatric university hospital, Cairo university were enrolled in the study. Nasopharyngeal aspirates (or endotracheal aspirates in intubated children) were examined with the DFA assay as well as rRT-PCR as a gold standard for the detection and quantification of hMPV.
    Results and
    Conclusion
    Human MPV was detected in two cases by DFA and in four cases by rRT-PCR among hospitalized children with ARTIs. The DFA assay proved to be a highly specific test, yet with low sensitivity when compared to rRT-PCR. Most of hMPV-infected cases presented during the winter season, with January and February exhibiting the highest hMPV activity. Pneumonia was the most common presentation of ARTIs in hMPV-infected patients. Direct evaluation of respiratory specimens by DFA provides rapid results with low cost and a subsequent early medical management. However, its use should be restricted as a first-line approach, and a confirmatory test would be needed for a definite diagnosis.
    Keywords: Direct Fluorescent Antibody Assay, Polymerase Chain Reaction, Human Metapneumovirus, Pneumonia, Infants
  • Ahmed Ben Hadj Hassine*, Manel Marzouk, Hichem Bargui, Miniar Tfifha, Mohamed Dhaou, Jalel Boukadida Page 11
    Introduction
    The Bacille Calmette-Guérin (BCG), a live attenuated Mycobacterium bovis vaccine, is administered to all the newborns in Tunisia in order to prevent Tuberculosis (TB). Complications of this vaccine are uncommon. However, it poses a risk for children with unknown immunodeficiency.
    Case Presentation
    We report on disseminated BCG disease in two infants, respectively, with severe combined immunodeficiency and human immunodeficiency virus (HIV). Evolution was fatal for both, despite adequate anti-tuberculosis treatment.
    Conclusions
    Molecular methods are available to respond to the urgent need for rapid and specific diagnosis of local/regional or systemic BCG disease, using available commercial kits GenoType® MTBC and GenoType® MTBDRplus. These tests allow prevention of inoculation of live vaccines such as BCG among the next siblings until appropriate screening tests exclude primary or secondary immunodeficiency syndromes.
    Keywords: Bacille Calmette, Guérin Vaccine, Mycobacterium bovis, Molecular Diagnostic Techniques, Immunologic Deficiency Syndromes
  • Amirmorteza Ebrahimzadeh Namvar*, Seyed Asghar Havaei, Leila Azimi, Abdolaziz Rastegar Lari, Ramazan Rajabnia Page 12
    Background
    Staphylococcus epidermidis is known as the most significant cause of nosocomial infections. Moreover, bloodstream infection is one of the noticeable and common infections in many wards of health care units, especially in intensive care units (ICU) and neonatal intensive care units (NICU). It has been proved that the mecA gene is the principal cause of methicillin resistance in Staphylococcus epidermidis strains. Also, mecA and other genes are located on staphylococcal cassette chromosome mec (SCCmec).
    Objectives
    The aim of this study was investigating the genotypic characteristics of methicillin resistant Staphylococcus epidermidis (MRSE) strains isolated from hospitalized patients at the intensive care unit.
    Methods
    A total of 121 isolates were recovered from bloodstream infections of ICU hospitalized patients in Al-Zahra hospital (Isfahan, Iran). Overall, fifty-three isolates belonged to S. epidermidis. Antibiotic susceptibility Test, determination of mecA gene, SCCmec types, Pulse Field Gel Electrophoresis (PFGE) and Multi-Locus Sequence Typing (MLST) methods were carried out as the preferential techniques.
    Results
    In accordance to our study, 43.4% of isolates were resistant to cefoxitin, while the mecA gene was found in 25 (47.2%) isolates by the PCR method. In addition, various SCCmec types were detected from MRSE strains by using multiplex polymerase chain reaction (PCR). Furthermore, a total of 16 different pulsotypes were identified with PFGE typing via GelCompar II analysis. It is notable that the most prevalent ST type was ST2.
    Conclusions
    Recognizing the source of infection is essential for monitoring the dissemination of infections, therefore this important issue is not acquired without various typing methods.
    Keywords: Molecular Characterization, PCR, ICU, S. epidermidis
  • Mohammad Javad Nasiri, Abdolrazagh Hashemi Shahraki, Abbas Ali Imani Fooladi, Hossein Dabiri*, Mohammad Mehdi Feizabadi Page 13
    Background
    Rapidly growing mycobacteria (RGM) are increasingly recognized as a cause of human infections. Rapid and reliable identification of RGM at species level should be carried out as a means of effective patient managements.
    Methods
    Twenty clinical samples of RGM isolated from suspected tuberculosis (TB) patients were included. Different phenotypic tests and a hsp65-PCR restriction analysis (PRA) method were used to identify the isolated organisms to species level. Sequence analysis of the rpoB gene was also used for molecular identification of clinical isolates.
    Results
    Phenotypic evaluation of clinical isolates assigned 19 (95%) isolates of RGM to M. fortuitum complex. Using hsp65-PRA, 13 isolates of M. fortuitum complex were identified as M. fortuitum, 4 isolates as M. abscessus and 1 isolates as M. chelonae. However, two isolates had identical hsp65-PRA patterns; one was indistinguishable from M. conceptionense and M. senegalense and another was indistinguishable from M. peregrinum and M. porcinum. By the rpoB gene sequence analysis, all species studied were readily discriminated from each other.
    Conclusions
    rpoB gene sequencing has a high discriminatory power, which easily permits the identification of clinical isolates of RGM to the species level. It unambiguously differentiates between closely related species with restricted biochemical and PRA differences. This procedure is suggested as a first-line identification method for RGM.
    Keywords: Mycobacterium, Sequencing, Iran, rpoB Gene
  • Hoshang Gorjipour, Golnaz Eslamyan, Mehrnaz Mesdaghi*, Mahboubeh Mansouri, Abdollah Karimi, Payman Eshghi, Delara Babaie, Mehrdad Amirmoeni, Bahram Bashardust, Marjan Shakiba, Zahra Chavoshzadeh Page 14
    Nijmegen breakage syndrome is a rare autosomal recessive congenital disorder causing chromosomal instability, characterized by short stature, microcephaly, distinctive facial features, recurrent respiratory tract infections, an increased risk of cancer, intellectual disability, and other health problems. People with Nijmegen breakage syndrome have immunodeficiency. Some patients with ataxia telangiectasia-like syndromes (about 10%) have decreased serum IgA and IgG levels with normal or raised IgM level, a phenotype reminiscent of hyper IgM syndrome, which is due to class switch recombination defect. The case presented in this report was an eight-year-old female with related parents, who had been admitted to the hospital several times with recurrent infections (pneumonia and sinusitis). In immunological workups, she had high IgM, low IgG, and IgA levels. According to high α-fetoprotein level and her microcephaly, Nijmegen breakage syndrome was suggested. She was receiving IVIg monthly for two years, when she developed hypersplenism and pancytopenia. Her bone marrow aspiration and biopsy was reported normal twice. The patient underwent Rituximab therapy (375mg/m2) weekly for four weeks, with good response and improvement of splenomegaly and pancytopenia. Class switch recombination defects should be considered in patients with ataxia telangiectasia variants, especially when they have hyper IgM phenotype, and if they present lymphoproliferation, Rituximab therapy could be an effective treatment.
    Keywords: Nijmegen Breakage Syndrome, Rituximab