Tehran University Medical Journal

Background: Jaundice is the most common cause of neonatal admission within the first month after birth. Therefore, by identifying the causes of jaundice based on the infant’s age at disease onset and age at hospital admission and providing the required training, jaundice can be managed and its associated complications can be prevented. This study was performed to evaluate the causes of neonatal jaundice, based on the infant’s age at disease onset and age at hospital admission.

Methods: In this cross-sectional study, out of 3,130 infants with jaundice, referring to Ghaem Hospital, Mashhad, Iran, from 2003 to 2015, 2,658 newborns were selected. Causes of jaundice are determined based on hematocrit, direct and indirect bilirubin, Coombs test, reticulocyte count, blood group and Rh of mother and neonate, thyroid tests, glucose-6-phosphate dehydrogenase (G6PD) enzyme testing, urinalysis, urine culture, and If necessary, Na, blood urea nitrogen, creatinine and other tests depending on the doctor's supervision. After confirming jaundice in infants, based on the physician’s diagnosis and laboratory results, a researcher-made questionnaire including the infant’s characteristics, was completed.

Results: Based on our study, 27.9% of infants had identified as causes of jaundice. Known causes of jaundice were blood group incompatibility (40%), infection (19%), G6PD enzyme deficiency (12%), endocrine disorders (8%), neonatal hypernatremic dehydration (7%), polycythemia (6%), congenital heart disease (CHD) (4%), occult bleeding (3%) and Crigler-Najjar syndrome (2%). The most common time of hospital admission of jaundice was 4-6 days after birth due to blood incompatibilities, occult bleeding, endocrine disorders, hypernatremic dehydration, CHD, polycythemia and G6PD enzyme deficiency. Moreover, the most common time of admission due to infection was after the first week of birth.

Conclusion: The most common age of onset of jaundice was first three days of birth for blood incompatibility, although they were admitted two days later. Therefore, neonatal admission at appropriate time at onset of jaundice and receiving prompt treatments can reduce the probable complications (e.g., kernicterus).

Background: Congenital hypothyroidism is a major but preventable cause of mental backwardness in infants. In case of hypothyroidism in fetuses, certain complications will occur in vital organs like the central nervous system and the skeleton. Before screening programs were introduced, congenital hypothyroidism was diagnosed with delay due to its few and non-specific symptoms during the first days of life. Given the difference in reference range for various races and populations, this study was aimed to determining a natural range for thyroid hormones used in the screening of infants.

Methods: In a descriptive cross-sectional study at Vali-asr Hospital, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran, from March 2013 to 2014. The level of T4, FT4 and TSH hormones was measured in all natural childbirth, without any complications and with one-minute Apgar score above 7 while this study was underway.

Results: A group of 249 infants (male and female), including 35 (14.1%) aged between 0 and 4 days, 102 (41%) aged between 5 and 7 days and 112 (45%) aged between 7 and 30 days, were examined. The average TSH, T4 and FT4 amounts in infants, aged 0 to 30 days, were respectively 5.35 µU/ml, 10.77 µg/dl and 1.33 ng/dl. The interval was 4.76-6.01 µU/ml for TSH, 10.36-11.17 µg/dl for T4 and 1.29-1.37ng/dl for FT4. The difference between age groups with average TSH concentration is not meaningful (P=0.7) and the average T4 amount in different age groups was meaningfully different (P=0.05). The average FT4 in different age groups is meaningfully different (P=0.007). The thyroid hormone amounts calculated for males and females were not significantly different.

Conclusion: Given the difference in the reference range in race, population and geographical zones, it is necessary to determine a range for screening in Iran. According to the findings of the present study, lower cut-offs, compared with western countries, should be envisaged for TSH in congenital hypothyroidism screening programs that could speed up the diagnosis of minor cases of the disease and prevent complications.

Background: Background gamma radiation levels vary in different locations and depended on many factors such as radiation properties of soil, building materials as well as construction types which human lives on it. People are always exposed to ionizing radiation, which could badly influence their health. The aim of this study was to evaluate the background gamma-ray dose rate and the estimated annual effective dose equivalent and determination of excess lifetime cancer risk in Sabzevar City, Iran.

Methods: The aim of this cross-sectional study was to determine the dose rate of background gamma radiation in outdoor an indoor areas, 26 stations were selected using the map of the Sabzevar City. The amount of gamma radiation was measured at 4 months (September to January) in 2014 year. The dosimeter used in this study was a survey meter, that is designed for monitoring radiation of x, gamma and beta rays.

Results: The obtained results show that there are significant differences between the indoor and outdoor exposures (P> 0.05). We did not observe significant differences between the time of sampling and sampling locations, (P<0.05). The minimum and maximum values of dose rate were found 66±20 nSvh-1 and 198±28 nSvh-1. The annual effective dose for Sabzevar residents was estimated to be 0.85 mSv and also the amount of excess lifetime cancer risk was estimated 3.39×10-3.

Conclusion: According to the results, the excess lifetime cancer risk and the annual effective dose for the Sabzavar City residents due to the background gamma radiation was higher than the global average (0.5 mSv). The epidemiological studies have been proposed to evaluate the risk of chronic diseases associated with natural radiation exposure among residents.

Background: Coagulase-negative staphylococci (CoNS) were considered as contaminats previously, but, during the past decade considered as one of the most common photogenic bacteria in hospital. Resistance to beta-lactams especially methicillin in staphylococcus species is being worrying in hospitals. Rapid identification of mechanisms of resistance and confirmation of their resistance to methicillin is a basic principle for antibiotic treatment. The aim of this study was to determine antibiotic resistance, frequency of mecA gene, and determination of SCCmec types in CoNS isolates from teaching hospitals in Iran.

Methods: The descriptive cross-sectional study was carried out one hundred clinical samples isolated from patients with an average age of 7-69 years at teaching hospitals in Hamadan City, Iran, from September 2014 to February 2015. After confirmation of isolates by microbiological standard biochemical tests, antimicrobial susceptibility testing was performed by disk agar diffusion (DAD) method. After extraction of isolated genomicm, mecA gene was detected. Then, the types of SCCmec were performed by PCR.

Results: In this study, 387 clinical samples were collected which among 100 CoNS isolated, Staphylococcus epidermidis was the most prevalent species with frequency 55 (55%), followed by S. haemolyticus 40(40%) and S. saprophyticus 5(5%). The highest antibiotic susceptibility was to rifampin 96(96%) and the lowest resistance was detected for trimethoprim/sulfamethoxazole (TMP/SMX) 47(47%). None of the strains were resistant to vancomycin. Resistance to methicillin was detected in 50% of CoNS isolates. Typing of SCCmec was performed by The polymerase chain reaction (PCR). Frequency types of SCCmec was type III with frequency 13(13%), type V 11(11%), type II 6(6%), type IV 4 (4%), type I 3(3%) respectively. Thirteen isolated was not typable in this study.

Conclusion: The result of this study showed that a large percentage of coagulase-negative staphylococci are resistance to methicillin, and the prevalence of SCCmec type was type III, which encodes the largest number of resistance genes. This information could be use in epidemiological study for preventing of infectious control in hospital and health centers.

Background: High-resolution manometer (HRM) of the esophagus has become the main diagnostic test in the evaluation of esophageal motility disorders. The development of high-resolution manometry catheters and software displays of manometry recordings in color-coded pressure plots have changed the diagnostic assessment of esophageal disease. The first step of the Chicago classification described abnormal esophagogastric junction deglutitive relaxation. The latest classification system, proposed by Pandolfino et al, includes contraction patterns and peristalsis integrity based on integrated relaxation pressure 4 (IRP4). It can be discriminating the achalasia from non-achalasia esophageal motility disorders. The aim of this study was to assessment of clinical findings in non-achalasia esophageal motility disorders based on the most recent Chicago classification.

Methods: We conducted a prospective cross-sectional study of 963 patients that had been referred to manometry department of Gastrointestinal and Liver Research Center, Firozgar Hospital, Tehran, Iran, from April, 2012 to April, 2015. They had upper GI disorder (Dysphasia, non-cardiac chest pain, regurgitation, heartburn, vomiting and asthma) and weight loss. Data were collected from clinical examinations as well as patient questionnaires. Manometry, water-perfused, was done for all patients. Manometry criteria of the patients who had integrated relaxation pressure 4 (IRP4) ≤ 15 mmHg were studied.

Results: Our finding showed that the non-achalasia esophageal motility disorders (58%) was more common than the achalasia (18.2%). Heartburn (68.5%), regurgitation (65.4%) and non-cardiac chest pain (60.6%) were the most common clinical symptoms. Although, vomiting (91.7%) and weight loss (63%) were the most common symptoms in referring patients but did not discriminate this disorders from each other’s. Borderline motor function (67.2%) was the most common, absent peristalsis (97%) and the hyper-contractile esophagus were rarest in the non- achalasia esophageal motility disorders.

Conclusion: However, achalasia is a treatable esophageal motility disorder but non-achalasia esophageal motility disorders were more common. Thus, manometrial study is an imperative tool for proper diagnosis and treatment of these patients, especially in gastro-esophageal reflux disease. Clinical finding could not accurately diagnosis between different types of non-achalasia esophageal motility disorders from each other’s.

Background: Human leukocyte antigen E is a member of non-classical HLA class I. Interaction between HLA-E molecule on the target cells and inhibitory CD94/NKG2A receptor on the cell surface of natural killer (NK) cells has an important role in the regulation of immune system against pathogens; therefore different cell surface expression of HLA-E molecule plays an important role in host resistance against viral infections as well as host response to treatment. Considering this fact, we analyzed the frequency of different HLA-E genotypes (HLA-E*01010101, HLA-E*01030103, HLA-E*01010103) in major thalassemic patients who underwent frequent transfusion therapy and are thus more susceptible to infectious diseases.

Methods: This study was a cross-sectional study of 104 major thalassemic patients who referred to Tehran Thalassemia Clinic between the years 2015 to 2016. Blood DNA was extracted and proliferated by sequence-specific primer polymerase chain reaction (SSP PCR). The PCR product was subjected to electrophoresis on 1.5 percent agarose gel then DNA fragment bands on the gel were detected by exposing to UV light. Furthermore, PCR products were also subjected to sequencing analysis for further confirmation.

Results: From 104 patients in this study, 49 (47.1%) were man and 55 (52.9%) were women. These patients were in the age range of 16 to 43 years (mean+SD; 31.03±4.7 year). The frequency of HLA-E*01010103 genotype (64.4 percent) was significantly (P= 0.001) higher than the genotypes of HLA-E*01010101 (15.4%) and HLA-E*01030103 (20.2%) whereas there was no difference between the frequency of HLA-E*0103 allele (52.4%) and HLA-E*0101 (47.6%).

Conclusion: This is the first study that examined the HLA-E polymorphisms in Iranian thalassemic patients referred to Tehran Thalassemia Clinic. This study has shown that the frequency of HLA-E*01010103 genotype was significantly higher than other genotypes of HLA-E whereas there was no difference between the frequency of HLA-E*0103 allele and HLA-E*0101 allele. Whether different frequencies of HLA-E genotype may affect thalassemic patients’ susceptibility to blood-borne infections will be of interest for future studies.

Background: Ankylosing spondylitis (AS) is an inflammatory disease that mainly affects axial skeleton of the body and ankylosing spondylitis ligaments around the spine at the junction of the spine are inflamed, because the disease is progressive and can lead to significantly cause of disability and the studies could provide a mechanism for the early detection of the disease or help determine when to start treatment, the difference in clinical presentations of AS in men and women is indicative of potential effect of gender on severity of the disease. This study was conducted with the aim to investigate the effect of gender on severity of AS.

Methods: In a cross-sectional study, one hundred and fifteen patients with ankylosing spondylitis who referred to Yazd Rheumatology Clinic between 2001 and 2013 were evaluated. Sampling was performed using non-random convenient method. The most important variables studied included demographic data, clinical presentation, radiographic stage of sacroiliac involvement, and laboratory data extracted from patients’ files and recorded in questionnaires.

Results: Both groups according to age at diagnosis, presence of enteritis, peripheral joint involvement and laboratory data such as C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and hemoglobin were matched. Inflammatory neck pain was more prevalent in men than in women (77.2% against 51.8%; P< 0.05). Sacroiliac radiographic study revealed stage 1 involvement in 11.3% of men and 37% of women (P= 0.009), and stage 4 in 27.2% of men and 3.7% of women (P< 0.001), with a significant difference.

Conclusion: According to the results of the study, the time between age of onset and age at diagnosis, inflammatory pain in the neck and advanced stage in men than in women was higher. Although these findings suggest that gender may have an impact on the pattern and severity of AS but the time delay in diagnosis as a disease affecting the intensity and pattern should not be overlooked.

Background: Thyroid carcinoma is the most common endocrine malignancy. Medullary thyroid carcinoma (MTC) approximately accounts for 5-10% of all thyroid carcinoma. Nowadays, it is obviously, the mutations in REarranged during transfection (RET) proto-oncogene, especially, mutations in exons 10, 11 and 16 are associated with MTC pathogenesis and occurrence. Thus, early diagnosis of MTC by mutation detection in RET proto-oncogene allows to identify patients who do not have any developed symptoms. The aim of this study was to screening of germline mutations in RET proto-oncogene exons 17 and 18 in MTC patients and their first degree relatives in Iranian population.

Methods: In this cross-sectional study, three hundred eleven participates (190 patients, 121 their relatives) were referred to endocrine research center, Shahid Beheshti University of Medical Science during September 2013 until September 2015. The inclusion criteria were pathological and clinical diagnosis. After whole blood sampling, genomic DNA was extracted from peripheral blood leucocytes using the standard Salting Out/Proteinase K method. Nucleotide change detection in exons 17 and 18 was performed using PCR and direct DNA sequencing methods.

Background: Due to the presence of radiosensitive organs in the abdominopelvic region and increasing the number of requests for CT scan examinations, concerns about increasing radiation doses in patients has been greatly elevated. Therefore, the goal of this study was to determine the absorbed dose of radiosensitive organs and the effective dose in patients underwent abdominopelvic CT scan using ImPACT CT patient dosimetry Calculator (version 1.0.4, Imaging Performance Assessment on Computed Tomography, www.impactscan.org).

Methods: This prospective cross-sectional study was conducted in Imam Reza Hospital from November to February 2015 February 2015 in the Imam Reza Hospital, in Urmia, Iran. The demographic and dosimetric information of 100 patients who underwent abdominopelvic CT scan in a 6-slice CT scanner were obtained through the data collection forms. The demographic data of the patients included age, weight, gender, and BMI. The dosimetric parameters included pitch value, CT dose volume index (CTDI_vol), dose-length product (DLP), tube voltage, tube current, exposure time, collimation size, scan length, and scan time. To determine the absorbed dose of radiosensitive organs and also the effective dose in patients, ImPACT CT patient dosimetry calculator was used.

Background: Anode heel effect refers to reduction of radiation intensity in the anode side of X-ray tube. This variation in radiation intensity across the anode-cathode of X-ray tube can be benefited for decrease radiation exposure in some radiological examinations. The aim of this study was to evaluate the effect of anode heel orientation on the radiation dose received by the testes in male patients undergoing pelvic radiography.

Methods: This is a cross-sectional study, conducted at one of the teaching hospitals of Ahvaz, Jundishapur University of Medical Science Ahvaz, Iran, from September 2015 to March 2016. In order to measure the profile of radiation intensity variation, 13 paired sets of high radiosensitive cylindrical lithium fluoride thermo-luminescent dosimeters (TLD) aligned on the cathode-anode central axis upon the table and then irradiated using routine exposure parameters. The anode of X-ray tube was positioned toward the feet for 40 patients and toward the head for 39 patients undergoing pelvic radiography. For measure the entrance skin dose (ESD), 8 TLD chips were located on the central point of the radiation field and 5 TLDs were located on the testes position to measure the dose received.

Background: In recent years, use of powdered infant formula (PIF) milk for neonates feed is increasing; therefore, the quality control (QC) of PIF products is very important. The aim of present study was detection of toxigenic Bacillus cereus species in PIF milk using PCR assay.

Methods: The cross-sectional study was carried out on 125 samples of powdered infant formula milk (PIF) purchased between March 2015 and April 2016 in Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Briefly, 0.1 dilutions were prepared and inoculated on Bacillus cereus selective media (MYP) and incubated at 30 °C for 24 hours. The suspicious colonies were verified using biochemical tests based on standard methods. Final confirmation of studied isolates was carried out by ITS gene detection using polymerase chain reaction (PCR) assay. Presence of nonhemolytic enterotoxin (NHE) (linked to diarrhoea syndrome) and emetic toxin (EM) (linked to emetic syndrome) virulence genes were investigated using polymerase chain reaction assay. 

Conclusion: Our data revealed that near 80% of Bacillus cereus isolates have emetic toxin (EM) gene, as result virulence potency of this isolates is very high. However, the low number of this organisms in foods is very important and food safety protocols for these opportunistic toxigenic bacteria should be revised. Since the pasteurization process is ineffective on B. cereus spores; therefore, spores can remain in PIF milk and the vegetative bacterial cells can cause food poisoning in neonates. Therefore, modification of foods quality control protocols is essential in order to identify virulence genes in this bacterium.

Background: Cardiovascular disease (CVD) is the most common cause of death in the world that is mostly due to vascular disease. Myocardial infarction (MI) is the most lethal form of coronary heart disease Which is increasing in developing countries. This study was done to calculate and compare lost years of life due to death and disability for the most important cause of death (myocardial infarction) in the studied population.

Conclusion: The high burden of myocardial infarction, especially in men, raises the incidence of Myocardial Infarction a health priority and the need for proper planning in order to take effective measures for the prevention and treatment.