فهرست مطالب

  • Volume:7 Issue:62, 2019
  • تاریخ انتشار: 1397/12/07
  • تعداد عناوین: 15
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  • Mohammad Bagher Haghighi, Naghi Dara orcid , Roxana Mansour Ghanaie, Leila Azimi, Amirhossein Hosseiniorcid , Saleheh Tajalliorcid , Mahmoud Hajipourorcid , Aliakbar Sayyari, Farid Imanzadeh, Katayoun Khatami, Pejman Rohani, Beheshteh Olang Pages 8925-8933
    Helicobacter Pylori (H. pylori) as a gram-negative bacterium is the most common infection of the gastrointestinal tract, and worldwide it affects the children over three years of age. H. pylori could cause gastrointestinal and extra-intestinal manifestations. Antibiotic resistance can happen primarily and occurs during treatment. We aimed to evaluate the resistance gene of H. pylori obtained from gastric biopsy by polymerase chain reaction (PCR) method in Iranian children over 3 years old.
    Materials and Methods
    This study was a cross-sectional to evaluate the resistance gene of H. pylori obtained from gastric biopsy by polymerase chain reaction method for metronidazole and clarithromycin in children over three years old referring to the Mofid Children's Medical Center in Tehran, Iran.
    Results
    Finally, data from seventy-nine samples included (mean age=10.7 years and male gender = 60.8%). Beta Globulin (BG) gene were detectable in 75 (94.93%) specimens of 79 (100%). Seventeen out of 75 specimens showed positive results for molecular detection of H. pylori. The results of RFLP-PCR technique showed that mutation of RdxA gene in seven of 17 (41.1%) for Metronidazole resistance and one case of 17 (5.8%) mutation of 23Y RNA gene that leads to clarithromycin resistance.
    Conclusion
    Regarding the results of our study, it is better to check microbial resistance by culture and antibiogram for the antibiotic regimen of the first and second line of H. pylori treatment in children
    Keywords: Antibiotic resistance, children, Helicobacter pylori, Infection
  • Motasem Alsweitiorcid , Hiba Maittah, Boshra Adayleh, Mohammed Alnobani, Adel Alwahadneh, Mohammed Abu, Shukair , Raed Alzyoud Pages 8935-8940
    Background
    Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disorder caused by mutations in the MEFV gene. The disease is especially common among Mediterranean ancestry, mostly Armenian, Turkish, Jewish and Arab populations. We aimed to describe genotype pattern of FMF in the Jordanian children and to compare it with other populations.
    Materials and Methods
    A retrospective analysis of MEFV mutations in pediatric patients, who were below 14 years of age, diagnosed as FMF and followed up at Queen Rania Children’s Hospital in Jordan between 2014 and 2017.
    Results
    A total of 196 pediatric patients were diagnosed with FMF; 54% Females and 46% males. The mean age of patients was 7.8 ± 3.1 years; mean age at disease onset was 4.9 + 2.3 years old. MEFV gene mutations were homozygous in 47(24%) patients, heterozygous in 87(44.4%) patients, compound heterozygous in 55(28.1%), and negative genotype in 7(3.6%) patients. Five mutations were the most frequent; M694V, E148Q, M680I, M694I, respectively.
    Conclusion
    The five-founder FMF mutations were the most detected in Jordanian children but in different order than what had been reported
    Keywords: children, Familial Mediterranean fever, Jordan, MEFV Genotype
  • Fatemeh Ghaedi Heidariorcid , Jahanger Maghsoudi, Masoud Bahrami orcid , Gholamreza Kheirabadi Pages 8941-8950
     
    Background
    Nurses have an important role in taking care of self-injury patients and their attitudes would affect the quality of care for these patients. Controversial results have been reported about the nurses’ attitude.Also, culture and context affect nurses’ attitudes. The study aimed to explore the nurses' attitudes and beliefs about the provocative psychological factors for self-injury in an Iranian context.
    Materials and Methods
    The present study was a descriptive qualitative research that was conducted on 12 experienced nurses in taking care of self-injury patients from three hospitals of Isfahan, using purposive and snowball sampling. Data were gathered from January to July 2017 through individual semi-structured interviews and were analyzed using conventional content analysis approach and Graneheim and Lundman method.
    Results
    Findings of the study were described in two main categories including intrapersonal factors of self-injury and interpersonal factors of self-injury. The first main category contained two subcategories including poor self-awareness and self-esteem and personality immaturity. The second category consisted of three subcategories including outburst of emotions, losing spirituality and low psychosocial efficiency.
    Conclusion
    The study provide an insight into how people's mental immaturity contributing to the framing of people as vulnerable to self-injury. Therefore, it is necessary to develop and perform multiple psychological interventions such as training coping strategies to decrease the risk of self-injury. Also, policies should be adopted to promote psychosocial support for these patients
    Keywords: Attitudes, Nurses, Precipitating Factors, Self-Injurious Behavior
  • Sima Baridkazemi, Hamid Reza Bahrami, Reza Eftekhari Gol, Ehsan Mosa Farkhaniorcid , Seyed Javad Hoseini orcid Pages 8951-8958
     
    Background
    Congenital hypothyroidism (CH) is one of the most common causes of mental disability, which can be prevented in the case of early diagnosis and treatment. We aimed to study the some relevant risk factors for CH in neonates born in Khorasan Razavi Province, Iran.
    Materials and Methods
    This was a population-based case-control study conducted on 97,380 neonates.The study population consisted of neonates born from April, 2016 to March, 2018 and undergone a screening program for CH.Overall, 530 neonates diagnosed with CH by a specialist were assigned to a case group and the remaining were considered as controls. Information was extracted from the Sina Electronic Health Record System (SinaEHR®, Iran). Bivariate and multivariate logistic regressions were carried out to determine the associations between independent variables and CH.
    Results
    Of the 97,380 neonates, the case and control groups included 530 (248 females) and 96,860 (47,061 males) newborns, respectively. In multivariate analysis, the use of neonate formula (adjusted odds ratio [AOR]=0.63; 95% confidence interval [CI]: 0.43-0.93, P=0.02), medication during pregnancy (AOR=1.29; 95% CI: 0.86-1.94, P=0.23), maternal hypertension (AOR=3.25; 95% CI: 1.15-9.19, P=0.03), maternal depression (AOR=2.19; 95% CI: 1.16-4.14, P=0.02), maternal diabetes (AOR=0.65; 95% CI: 0.51-0.83, P=0.001), consanguineous marriage (AOR=1.34; 95% CI:1.12-1.60, P=0.002), place of residence, and birth season after adjusting for confounding variable remained in the final model.
    Conclusion
    The study findings showed that birth season, place of residence, maternal hypertension and depression, and consanguineous marriage can be the main risk factors for CH. However, further studies are needed to analyze the findings of the present study to be more confident about the causality of these relationships
    Keywords: Congenital hypothyroidism, Iran, Neonatal screenings, risk factors
  • Fatemeh Ghelichkhaniorcid , Mojgan Mirghafourvandorcid , Mohammad Asghari Jafarabadiorcid , Solmaz Ghanbari Homayiorcid , Ellahe Bahrami, vazirorcid , Azam Mohammadi orcid Pages 8959-8968
    Background
    Osteoporosis knowledge test is a comprehensive questionnaire that evaluates risk factors, nutrition and exercise recommendations, as well as general subjects such as bone evolution, diagnosis, and osteoporosis treatment. The aim of this study was to determine the psychometric characteristics of the revised version of osteoporosis knowledge test (OKT) in Iranian adolescent population.
    Materials and Methods
    This is a cross-sectional methodological study that studied 330 high school students. Sampling was conducted in public and private schools in Saveh, Iran. Schools and students in each school were randomly selected.The translation validity was examined using Forward and Backward translation. Content validity was examined in two qualitative (assessment of experts’ opinions) and quantitative (using the content validity ratio (CVR) and Content Validity Index [CVI]) parts. Face validity was determined on 30 high school students. The generalized factor analysis (GFA) was used to evaluate the construct validity of the instrument. The reliability was determined in terms of reproducibility via intra-class correlation coefficient (ICC) by test–retest and internal consistency (Cronbach’s alpha) on 20 participants.
    Results
    Content validity indices, CVI and CVR, for OKT were 0.97 and 0.99, respectively. Reliability was confirmed in two dimensions of intra-class correlation coefficient (ICC = 0.69), and internal consistency (α = 0.81). Construct validity was confirmed using the generalized factor analysis.
    Conclusion
    Findings support the validity and reliability of osteoporosis knowledge test. Therefore, it is recommended that the instrument can be used in both clinical practice and research in Iranian adolescent population
    Keywords: Adolescent, Knowledge, Osteoporosis, Psychometric, Reliability, Validity
  • Shirin Sadat Ghiasi, Hassan Mottaghi Moghaddam shahri orcid , Elahe Heidari Pages 8969-8976
     
    Background
    Congenital heart disease (CHD) is the most common lethal congenital anomaly. Early diagnosis of CHD by fetal echocardiography based on maternal and fetal indications is important and lifesaving. The aim of study was to assess the referral aspects of pregnant women to pediatric cardiologist.
    Materials and Methods
    This was a retrospective cross-sectional study on 250 documents of referred pregnant women, which was conducted in Imam Reza hospital (Mashhad city, Iran) from 2012 to 2017. Relevant factors of referral to pediatric cardiologist were assessed in an unselected population of pregnant women, mostly based on guideline indications. Data were analyzed using SPSS software version 16.0.
    Results
    From 250 fetuses 59.8% were male. The most common reasons of referral were abnormal ultrasonography and family history of CHD with 83% and 28.8 %, respectively, which were referred mostly by gynecologist (53.7%). Fetuses were mostly singleton (98. 8%). Five and six percent had associated extra-cardiac anomalies, mostly central nervous system and renal disorders. The mean age of referred pregnant women was 31.5+5.14 years. The mean age of gestation was 24.5+ 6.09 weeks. Seventy-one cases (28.4 %) have similar history in prior children.
    Conclusion
    Timely referral to pediatric cardiologist as an extraordinary benefit for pregnant women and also ongoing follow- up for the baby is requires an organized observation. Assessment and comparison with universal guidelines reveals our shortcomings. More than half of referred cases were identified too late in time and the whole indications were not done accurately
    Keywords: Congenital heart defects, Fetal echocardiography, Pediatric cardiologist
  • Mahmoud Hajiahmadi, Mohammad Pornasrollah, Faeze Aghajanpourorcid , Morteza Alijanpour Aghamaleki, Zahra Oruji Pages 8977-8984
     
    Background
    Considering the increasing prevalence of type 1 diabetes mellitus (T1DM) as an autoimmune disease in recent years and the positive effects of vitamin D (VD) on this disease, especially the preventive effect of VD on progressive reduction of pancreatic β-cells, we aimed to investigate the effect of VD on pancreatic β-cell function in T1DM patients.
    Materials and Methods
    From Sep 2016 to Nov 2017, this single-blind clinical trial study was performed on patients who have affected with T1DM in the last five years, referred to Endocrinology Clinic of Amirkola Children's Hospital in Babol city of Iran. The patients with VD level less than 30 ng/mL were treated with 50, 000IU Pearl VD for 9 months. The patients' C-peptide, 25 (OH) D, HbA1C and total daily dose(TDD) insulin were compared at the beginning and end of the study. Data were analyzed using SPSS software version 22.0.
    Results
    By examining all 30 randomly selected children meeting the inclusion criteria, it was found that VD increased the C-peptide level (0.06 nmol/L), slightly improved the pancreatic β-cell function as well as decreased their HbA1c (0.64%), and TDD insulin levels (0.05 unit) although none of the relationships was significant. However, a significant decrease in HbA1c level was found in the female group (p=0.04) as well as in the age group less than 10 years (p=0.007).
    Conclusion
    VD intake had no significant effect on serum C-peptide levels and reduction of HbA1c and TDD insulin though a significant decrease in HbA1c level was observed in the female group and in the patients less than ten years
    Keywords: C-Peptide, Pancreatic ? Cells, Pediatric, Type 1 Diabetes Mellitus, Vitamin D
  • Foroogh Amirabadi, Shirin Saravani orcid , Ghasem Miri, Aliabad, Mahnaz Khorashadi, Zadeh Pages 8985-8991
    Background
    b-thalassemia major is a common hereditary blood disease that can affect patients’ oral health and quality of life. The present study aims to determine the relationship between health of deciduous teeth and the Oral Health-Related Quality of Life (OHRQoL) in children diagnosed with β-thalassemia major compared with healthy children.
    Materials and Methods
    This cross-sectional study was performed on 50 children diagnosed with β-thalassemia major and 50 healthy children aged 3-6 years old. Decayed, missing, and filled teeth (dmft) of the participants were measured according to the World Health Organization (WHO) criteria and the OHRQoL with the Early Childhood Oral Health Impact Scale (ECOHIS). Data were analyzed using SPSS software version 19.0.
    Results
    The results showed that the dmft index of the patient group with a mean of 5.36 was significantly higher than the healthy group with a mean of 3.36. The mean OHRQoL in the patient group (19.24) was significantly higher than that of the healthy group (11.24). The mean dmft had a significant positive relationship with the ECOHIS score of the children with thalassemia major (r=0.769, p=0.000), and healthy children (r=0.756, p=0.000).
    Conclusion
    According the results, the positive correlation between the dmft index and the mean OHRQoL indicated that dental problems in most children with β-thalassemia major are associated with a poorer OHRQoL. Since the dmft index and ECOHIS were higher among children diagnosed with β-thalassemia major, the prevention and treatment of dental problems seem necessary for improving their quality of life
    Keywords: Beta-Thalassemia, children, dmft index, Quality of life
  • Najmeh Rajabi Gharaii, Zahra Hesarinejad, Masoome Nasibi, Masumeh Ghazanfarpour , Faezeh Ghorbani, Leila Kargarfard Pages 8993-9001
    Background
    It is necessary to identify women who discontinue the breastfeeding to achieve the purpose of increasing the length of breastfeeding. To this end, Breastfeeding Attrition Prediction Tool (BAPT) has been developed. The current systematic review aimed to comprehensively review the validity and reliability of BAPT scale with different versions to give comprehensive information for authorities in this field.
    Materials and Methods
    Three English databases including Medline (via PubMed), Scopus, and Cochran library until May 2018 with no date restriction were searched. The search strategy was developed based on main terms of (Breastfeeding Attrition Prediction Tool OR BAPT) AND (Reliability OR validity OR Psychometrics OR Factor Analysis). Two reviewers separately extracted the required data available in full-text of all the quality of related studies was investigated using COSMIN checklist.
    Results
    All Cronbach alpha coefficient (both overall and subscale) were in excess of 0.7 except for subscale "NBS" in American version and subscale PBS in Persian version. In term of discriminant and predictive validity, BAPT revealed a good ability to classify women with or without breastfeeding. BAPT predicted breastfeeding status at postpartum period but it was not able to predict breastfeeding status in the third trimester of pregnancy. In term construct validity, four-factor solution of original English version was confirmed in Turkish, Persian and English other version.
    Conclusion
    Overall, the findings of systematic review supported that BAPT may be a valid (content, predictive and construct validity), and reliable (internal consistency and re-test reliability) instrument to use in both researches and clinics to identify mothers who are at risk of breastfeeding stop
    Keywords: Breastfeeding attrition prediction tool, Psychometric, Systematic review, Questionnaire
  • Azar Dastranji, Nemat Bilan Pages 9003-9012
    Background
    About 40 to 60% of all patients admitted to pediatric intensive care unitsundergo mechanical ventilation and 10 to 20% will fail to be extubated. We aimed to determine the role of the rapid shallow breathing index (RSBI) in predicting successful weaning of pediatric patients with respiratory failure.
    Materials and Methods
    This cross-sectional study, was performed on 72 mechanically ventilated children (36 in the lung failure group and 36 in the pump failure group) who were admitted in Tabriz children’s hospital in pediatric intensive care unit (PICU), Tabriz city, Iran. In order to spontaneous breathing trial (SBT) criteria, the patients who had FiO2 less than 40%, PEEP less than or equal to 5 cmH2O and PaO2 higher than 60 mmHg, was placed on spontaneous ventilation mode (PSV+CPAP) to maintain a PEEP of less than or equal to 5 cmH2O, PS of less than or equal to 8 cmH2O and FiO2 of less than or equal to 40%. After 2 hours, measured tidal volume and respiratory rate to calculate the RSBI then the patient was extubated.
    Results
    From 72 patients were enrolled in this study, 26 patients failed in extubation. The total RSBI threshold was 6.7 breath/min/ml/kg (AUC = 0.739, 95%CI = 0.618 – 0.861; p = 0.001)) with a sensitivity of 73.1% and a specificity of 80.4% for success of extubation. Patients successfully extubated had significantly lower RSBI 4.65 ± 3.03 breath/min/ml/kg compared to extubation failuregroup.
    Conclusion
    Based on the result of this study, the rapid shallow breathing index with a threshold of 6.7 breath/min/ml/kg was considered to be an acceptable and practical criterion for predicting the outcome of weaning in children
    Keywords: Airway extubation, Intra tracheal intubation, Pediatric, Respiratory failure
  • Sakineh Rakhshanderou, Yadollah Mehrabi, Mohtasham Ghaffari Pages 9013-9025
    Background
    Availability and accessibilityarereported as the main determinants of fruit and vegetable consumption among children. The present study was conducted to assess the status of availability and accessibilityto fruit and vegetable at school and home among Iranian adolescents in Tehran, Iran.
    Materials and Methods
    This cross-sectional study was conducted to assess status of fruit and vegetable availability and accessibilityamong Iranian adolescents. In this study, 500 adolescents aged 11 to 14 years old were investigated in Tehran, Iran. Subjects were chosen by multi-stage random sampling method. The data collection tool was a valid researcher-made questionnaire consist of 21 questions. The data was analyzed using SPSS software version 16.0.
    Results
    68% (n=344) and 27.2% (n=136) of students reported that fruit and vegetables is available in their home always, respectively. Also, 19.6% (n=98), and 58.4% (n=292) of students reported that most of the times and always unhealthy foods were sold in schools’ buffets, respectively; 88% (n=440) of students declared that they are allowed to take fruit and vegetable from the refrigerator and eat any time they want to. Results showed no significant difference between boys and girls in terms of availability and accessibility(P=0.268). In addition, there was a significant relationship between variables of residential area, family and home size, birth order and the parents’ education level and availability and accessibility (P<0.05).
    Conclusion
    Fruit and vegetable availability and accessibility was not acceptable yet among guidance school students in Tehran.It is recommended to implement proper interventions for families, school managers as well as students to promote availability and accessibilityof fruit and especially vegetable for adolescents
    Keywords: Availability, Accessibility, Fruit, Iran, Students, Vegetable
  • Valentina Talarico orcid , Sara Rizzo, Maria Cirillo, Paola Chiarello, Roberta Bianchi, Roberto Miniero, Maria Concetta Galati, Giuseppe Raiola Pages 9027-9036
     
    Background
    Kawasaki disease (KD) is the second most common childhood vasculitis and one of the main causes of acquired heart disease in children. Recent work focuses on the early diagnostic importance of those risk factors that indicate resistance to intravenous immunoglobulin (IVIG) treatment. The objectives of this study were to identify clinical, laboratory and/or instrumental factors that could be correlated with the risk of resistance to IVIG and the applicability of standard score systems.
    Materials and Methods
    We retrospectively reviewed clinical records of 23 children with KD, diagnosed in five consecutive years. They all underwent laboratory and echocardiography investigations and initial treatment with IVIG. Based on the response to IVIG they were divided into two groups: IVIG responders (n=14), and IVIG non-responders (n=9).
    Results
    39% (n= 9) of patients were non-responders. Laboratory exams were overlapping between the two groups except for platelets (p <0.05), and for triglycerides (p<0.01). Among the patients who showed cardiac involvement, 67% were IVIG-resistant (p=0.0094; odds ratio [OR] = 20.0). Coronary artery abnormalities (CAA) at onset were present in 8.69% of patients, all non-responders (p=0.1423; OR=9.66). In this group of patients there were lower values ​​of sodium (p<0.05), and of albumin (p<0.04), and higher bilirubin (p<0.01).
    Conclusion
    In our population it has emerged that some laboratory (low platelet levels, high triglyceride levels), and instrumental factors (CAA at onset, especially if associated with hyponatremia, hypoalbuminemia and hyperbilirubinemia) should be evaluated at the time of diagnosis, as important prognostic factors with a more severe KD shape and greater resistance to IVIG
    Keywords: children, Intravenous Immunoglobulin, Kawasaki disease, Resistance
  • Shirin Djalalinia, Reza Arjmand orcid , Mehri Gholami, Yasaman Shaker, Sahar Saeedi Moghaddam, Kumars Pourrostami, Omid Safari, Nasrin Elahimehr, Saeed Nik Khah, Ehsan Zahmatkesh, Esfandiar Najafi Tavana, Mostafa Qorbani Pages 9037-9047
     
    Background
    Brucellosis is a zoonotic disease that is widely distributed throughout the developing countries. Children are considered as at risk groups for infection. The aim of this study was to assess the frequency and clinical manifestations of Brucellosis in Iranian children and adolescents.
    Materials and Methods
    We systematically searched international databases; ISI, Medline (via PubMed), Scopus, and national databases Irandoc, Barakat knowledge network system, Magiran, and Scientific Information Database (SID). The search strategy was developed based on main terms of "Brucellosis," "Brucella fever", "Gibraltar", "Rock Fever", "Undulant Fever", "Cyprus Fever", "Malta Fever", and "Bang Disease".
    Results
    A total of 885 studies were identified, from them a total of 12 studies that were conducted between 2001 and 2016 were included. Following the relevancy assessments and quality control, data from the 1,429 participants were presented in our review. The age of the patients ranged from 2 to 18 years. Only one out of twelve studies provided the prevalence of 4.30% and 3.4 incidence. Studies varied greatly in reporting high risk behavior of animal contact (8.4 to76.0%) and unpasteurized dairy (22.4 to 91.6%).
    Conclusion
    Our finding reveals the disparity of reported prevalence and clinical manifestations of Brucellosis in Iranian children. Fever and joint pain were the most frequent reported signs. Differences in study design, measurement tools and methods, and sub population sampling, does not provide the possibility of aggregation of data for more comprehensive inference
    Keywords: Brucellosis, children, Clinical manifestations, Iran
  • Suresh Angurana, Arun Bansal orcid , Ankit Mehta, Sandeep Bansal, Muralidharan Jayashree Pages 9049-9052
    Chronic suppurative otitis media (CSOM) is a common childhood infectious disease in developing countries. It may be associated with various life threatening intra-cranial or extra-cranial complications. We report a 10 year-male child with a rare combination of right sided unsafe CSOM, mastoiditis, Bezold abscess, sigmoid and transverse sinus thrombosis, and bilateral abducens nerve palsy and he was successfully treated with antibiotics, surgery, and anticoagulation. The combination of CSOM with mastoiditis, Bezold abscess, sigmoid and transverse sinus thrombosis, and bilateral abducens nerve palsy is rare. Aggressive management with prompt antibiotic therapy, surgery, and anticoagulation can lead to favorable outcome.
    Keywords: Abducens nerve palsy, Bezold abscess, Child, Chronic suppurative otitis media, Mastoiditis
  • Seyed Hamid Reza Abtahi, Ali Malekzadeh, Saeed Soheilipour, Mansour Salehi, Roya Taleban, Reyhaneh Rabieian, Mohammad Moafi orcid Pages 9053-9060
     
    Background
    Non-syndromic hearing loss (NSHL) is assumed as one of the highly prevalent congenital defects in the world. In this regard, gap junction protein beta 2(GJB2), and gap junction protein beta 6(GJB6) mutations are considered as the leading congenital causes of deafness. The present study aimed to assess the prevalence of GJB2 and GJB6 mutations in NSHL cases.
    Materials and Methods
    This cross-sectional study was implemented from Jan. 2015 to Sep. 2017 at Alzahra Hospital (Isfahan, Iran).46 patients afflicted with NSHL were recognized and recruited by physicians. Heparinized blood was collected and DNA of each participant was extracted. Genetic analysis of GJB2 and GJB6 genes was performed using PCR and GAP-PCR methods respectively.
    Results
    35delG mutation had the highest prevalence with allelic frequency of 6.12%. The allelic frequencies of 35delG, and delE120 were 6(6.12%), and 3(3.06%), respectively. Allelic frequency of W77R, Y65H, G160, and R127H was 2(2.04%) for each of them. In addition, 2 patients were heterozygous for p.V153I rare polymorphism (2.04%).
    Conclusion
    Overall, the present study indicated that 35delG mutation could be considered as the foremost causative factor of NHCL. GJB2 mutations were highly prevalent among NSHL cases (23.9%). As a result, the mutation analysis of this gene could be appropriately used for prevention and early diagnosis of NSHL
    Keywords: Hearing Loss, GJB2, GJB6, Mutation