Investigation of Parvovirus B19, Cytomegalovirus, Herpes Simplex Virus Types 1 and 2, Human Papillomavirus Types 16 and 18 in Papillary Thyroid Carcinoma.

Background & Objective: Viral infections are associated with the pathogenesis and progression of human malignancies. Several studies have suggested the role of viral infections in papillary thyroid carcinoma (PTC). However, the results are still conflicting, and the potential role of viruses in PTC tumorigenesis remains to be elucidated. In the present study, we aimed to investigate the presence of parvovirus B19, cytomegalovirus (CMV), herpes simplex virus types 1 and 2 (HSV-1/HSV-2), and human papillomavirus (HPV) types 16 and 18 in PTC. Methods: In this cross-sectional study, paraffin-embedded tissue blocks of 40 patients with PTC were used. Tissue blocks were studied for the presence of the virus genome using real-time polymerase chain reaction (PCR). Results: Of the 40 patients with PTC, there was 1 positive case of HPV (2.5%), while 6 cases were positive for parvovirus B19. HSV and CMV DNAs were not detected in any cases. Conclusion: Correlations among HSV, CMV, and PTC are unexpected in our patient population. But parvovirus B19 and, to a lesser extent, HPV DNA genomes were detected in PTC using real-time PCR.

What is the appropriate aganglionic bowel length on contrast enema for attempting single stage transanal endorectal pull-through in Hirschsprung disease?

PURPOSE: To identify influence of different values of age and abnormal bowel length in HD patients selected for single stage TERPT which affects the technique of surgery. METHODS: This observational study was carried out for over 2.5 years. All children younger than 14 years old with clinical suspicion for HD, typical transitional zone (TZ) on contrast enema (CE) distal to splenic flexure, preoperative diagnosis approved by full thickness biopsy, no previous surgical history and no urgency were included. The distance between the anus and TZ was considered as aganglionic length on CE. Biopsy was taken from distal to proximal of resected bowel to reach circumferentially normal innervated bowel. Paired sample Student's t-test, Pearson correlation test, receiver operating characteristic (ROC) analysis were performed. RESULTS: Forty-eight patients were enrolled in this study. Measured mean for aganglionic bowel length on CE and pathology were 33.5 ±â€¯17.1 cm and 56.8 ±â€¯33.5 cm, respectively (p < 0.01). Correlation coefficient (R) and coefficient of determination (R2) were 0.632 and 40%, respectively (p < 0.01). The difference between radiologic and pathologic measurements in females was higher than males (mean: 29.3 vs 21.9 cm) but was not statistically significant (p = 0.75). There was statistically significant difference between CE and pathologic results in the infants younger than 10 months (p = .004). Abnormal bowel length equal to 52 cm predicted requirement of laparoscopy assistance/laparotomy with 75% sensitivity and 85% specificity. CONCLUSION: Our investigation showed it is safe to attempt for single stage TERPT when aganglionic length on CE is less than 52 cm and the child with HD is older than 10 months. Chance of requiring additional laparotomy or laparoscopy assistance is low in these patients. TYPE OF STUDY: Study of diagnostic test. LEVEL OF EVIDENCE: Level II.

A Randomized Clinical Trial Evaluating the Efficacy of Colistin Loading Dose in Critically Ill Children.

OBJECTIVE: Pharmacokinetic and clinical studies recommend applying loading dose of colistin for the treatment of severe infections in the critically ill adults. Pharmacokinetic studies of colistin in children also highlight the need for a loading dose. However, there are no clinical studies evaluating the effectiveness of colistin loading dose in children. METHODS: In a randomized trial, children with ventilator-associated pneumonia or central line-associated bloodstream infection (CLABSI) for whom colistin was initiated, were enrolled. Patients were randomized into two groups; loading dose and conventional dose treatment arms. In the conventional treatment arm, colistimethate sodium was initiated with maintenance dose. In the loading dose group, colistimethate sodium was commenced with a loading dose of 150,000 international unit/kg, then on the maintenance dose. Both treatment arms also received meropenem as combination therapy. Primary outcomes were overall efficacy, clinical improvement and microbiological cure. Secondary outcomes were colistin-induced nephrotoxicity and development of resistance. FINDINGS: Thirty children completed this study. There was a significantly higher overall efficacy in the group received loading dose (42.9 vs. 6.3%, P = 0.031). There weren't any significant differences in the clinical and microbiological endpoints. In the subgroup of children with CLABSI, results illustrated a trend toward (though statistically nonsignificant) better clinical cure for patients receiving loading dose. CONCLUSION: This preliminary study suggests that colistin loading dose might have some benefits in critically ill children, specifically in children with CLABSI. Further trials are required to elucidate colistin best dosing strategy in critically ill children with severe infections.

Antimicrobial Resistance Patterns of the Gram-positive Bacteria Isolated from Children with Bloodstream Infection in an Iranian Referral Hospital: A 6-year Study.

BACKGROUND: Bloodstream infections (BSI) are considered as a serious cause of morbidity and mortality in children. The aim of this study was to report the common Gram-positive bacteria (GPB) responsible for bloodstream infections in children and determine their antimicrobial resistance patterns in Children Medical Center (CMC) Hospital, Tehran, Iran. METHODS: This retrospective study was conducted within a six-year period (March 2011 to September 2016) for pediatric patients with BSI. Standard bacteriological methods were performed for identification of the bacteria. Antimicrobial susceptibility tests were evaluated by using the disk diffusion method according to the CLSI recommendations. RESULTS: Among 68233 blood cultures, 2349 isolates were obtained which 59% of them (N=1393) were GPB and 41% (n=956) were Gram-negative. The most common GPB isolates were Coagulase negative Staphylococcus (CoNS) (N= 609, 44%), followed by Staphylococcus aureus (N=319, 23%), Enterococcus spp. (N=139, 10%), Streptococcus pneumonia (N= 106, 8%), Streptococci viridans (N= 180, 13%) Micrococcus spp. (N=24, 1.7%) and Streptococcus group B (N= 16, 1%). The rate of methicillin resistance in S. aureus and CoNS was 47% (N=116/246) and 91% (N=557/609), respectively. Isolates of S. pneumoniae showed high-level of resistance to trimethoprim/sulfamethoxazole (N=28/33, 85%) and erythromycin (N=59/91, 65%). S. viridans isolates and Micrococcus spp. were highly sensitive to linezolid (100%). All of the tested isolates of Streptococcus group B were sensitive to all the antibiotics used in this study. Among Enterococcus spp., 52% (N=69/133) of the m were resistant to vancomycin. CONCLUSIONS: Our results emphasize the importance of a valuable guide in identifying resistance trends and selecting appropriate antibiotic.

Angiotensin-Converting Enzyme Gene Polymorphism in Children with Idiopathic Nephrotic Syndrome, Effect on Biopsy Findings.

OBJECTIVE: Angiotensin converting enzyme (ACE) converts angiotensin I into angiotensin II. The ACE gene shows an I/D polymorphism, which correlates with ACE concentrations. The aim of this study is to evaluate the distribution of the ACE I/D genotype in children with idiopathic nephrotic syndrome (INS) and healthy controls and study the effect of this polymorphism on clinical and pathologic findings. METHODS: ACE gene I/D polymorphism of 104 patients with INS and 119 controls were determined. RESULTS: The DD, ID, and II genotypes were found in 58.7%, 22.1%, and 19.2% of the patients, and in 79.8%, 2.5%, and 17.6% of controls, respectively (p > 0.05). The ID genotype was seen more frequently in patients resistant to treatment. CONCLUSION: The observed differences with previous reports suggest the influence of the genetic background on disease course. The ACE I/D gene polymorphism's role seems to be more important in renal disease progression than susceptibility.

Evaluating the Possibility of Defining Cut-Off Points for ΔFA% in Order to Differentiate Four Major Types of Peri-Tumoral White Matter Tract Involvement.

BACKGROUND: Diffusion tensor imaging (DTI) and its different scalar values such as fractional anisotropy (FA) have recently been used for evaluation of peri-tumoral white matter (WM) involvement to help define safer surgical excision margins. OBJECTIVES: The purpose of this study is to evaluate the possibility of defining diagnostic cut-off points for differentiating four major types of peri-tumoral WM involvement using FA. PATIENTS AND METHODS: DTI was performed in 12 patients with high presumption of having brain tumors, on a 1.5 T MRI scanner. DTI data was processed by MedINRIA software. Two-hundred region of interests (ROI) were evaluated: 100 in the lesion zone and the rest in the normal WM in the contralateral hemisphere. FA value related to each ROI was measured, and the percentage of FA decrement (ΔFAs%) was calculated. RESULTS: Of the 100 ROIs on the lesion side, 74 were related to high-grade lesions, 23 to low-grade ones, and three to "gliosis". There were 54 "infiltrated", 22 "displaced", 15 "disrupted", and 9 "edematous" tracts. The major type of fiber involvement, both in low-grade and high-grade tumors was "infiltrated, whereas "edematous" fibers comprised the minority. ΔFA% was more than -35 for "displaced" and "edematous" fibers, and less than -35 for the majority of "disrupted" ones, but "infiltrated" fibers had scattered distribution. Mean ΔFA% was the least for "disrupted", followed by "infiltrated", "edematous" and "displaced" parts. CONCLUSION: Introducing definite diagnostic cut-points was not possible, due to overlap. Based on the fact that "disruption" is the most aggressive process, a sensitivity analysis was carried out for "disrupted" fibers for several presumptive cut-off points.

The Relation between Helicobacter pylori Infection and Acute Bacterial Diarrhea in Children.

Background. H. pylori infection leads to chronic gastritis in both children and adults. But recently, there are arising theories of its protective effect in diarrheal diseases. Aim. To explore the prevalence of H. pylori infection in children with bacterial diarrhea and compare it with healthy controls. Patients and Methods. Two matched groups consisted of 122 consecutive children, aged 24-72 months old, with acute bacterial diarrhea, who had Shigellosis (N = 68) and Salmonellosis (N = 54) as patients group and 204 healthy asymptomatic children as control group enrolled in this study. Results. The prevalence of H. pylori infection in healthy control children was significantly higher than in patients group, (odds ratio = 3.6, 95% CI: 1.33-9.5, P = 0.007). In our study, only 2/54 Salmonella infected patients and 3/68 of Shigellosis had evidence of H. pylori infection, while normal control children had 27/204 infected individuals. Conclusion. H. pylori infection may play a protective role against bacterial diarrhea in children. So it is important to consider all of the positive and negative aspects of H. pylori infection before its eradication.

Changes in Structure, Interstitial Cajal-like Cells and Apoptosis of Smooth Muscle Cells in Congenital Ureteropelvic Junction Obstruction.

OBJECTIVE: The goal of this study is to evaluate some structural changes in muscular, collagenous and neural components as well as expression of Cajal-like cells and apoptosis of smooth muscle cells in congenital ureteropelvic junction obstruction (UPJO). METHODS: Tissue specimens were obtained from 25 patients with UPJO and compared with normal ureteropelvic junction regions of 19 autopsies. In paraffin embedded sections the amount of Cajal-like cells, density of nerve fibers and smooth muscle cell apoptosis (using immunohistochemical staining) were determined. Collagen deposition and muscular components were stained by Trichrome-Masson staining and evaluated by image analysis techniques. Arrangement of muscular bundles was also evaluated qualitatively. Findings : The number of Cajal-like cells was significantly lower in patients than in controls. The apoptotic score and mean number of nerve fibers were not statistically different for the two groups. Arrangement of muscular fibers was more irregular in patients than in controls (P<0.001). Collagen deposition was significantly higher in patients than in controls (P<0.001). The mean amount of muscular component was lower in patients than in normal ones. (P= 0.09) CONCLUSION: We found significant pathologic changes in congenital ureteropelvic junction obstruction such as decrease in Cajal-like cells, increase in collagen deposition and irregular arrangement of muscle fibers.

Contributory role of viral infection in congenital tumour development.

Congenital tumours are a group of distinct infrequent disorders whose exact aetiologies have not clearly been understood so far. Viral infection seems to be one of the key factors involved in the carcinogenesis of certain tumours. This study was performed to assess whether viral DNAs are present in the congenital tumours or not. Nucleic acid from 31 congenital tumours was extracted. Detection of Epstein-Barr virus, Cytomegalovirus (CMV), adenovirus, Herpes simplex virus 1 (HSV1) and 2, Human herpes virus 6 (HHV6), and BK virus was performed using polymerase chain reaction. Viral nucleic acid was detected in eight subjects (25.8%), mostly adenovirus, CMV, and HHV6. Despite their low frequencies, a possible role could be identified for viral infections in tumour development or progression.

Alpha 1 antitrypsin deficiency in infants with neonatal cholestasis.

OBJECTIVE: Alpha1-antitrypsin deficiency (A1ATD) is the most important indication for liver transplantation in children. The gene frequencies vary in different ethnic groups. In the present study, we attempt to determine the frequencies of the most common defective alleles, Z and S, in Iranian children suffering from idiopathic neonatal cholestasis. Eighty-seven infants were typed for Z and S alleles. METHODS: In a single center study, 87 consecutive liver biopsies from infants with cholestasis were reviewed and patients with neonatal cholestasis enrolled in the study and cases with confirmed biliary tract atresia excluded. Formalin fixed paraffin embedded blocks were used for DNA extraction. AAT genotype was determined by polymerase chain reaction (PCR) assay and amplification of the two most common deficiency variants, S and Z alleles, and then sequencing of PCR products. FINDINGS: There were 48 (55.2%) males and 39 (44.8%) females, with a median age of 60 days. Out of 87 of the study subject, 2 (2.2%) were heterozygous for the S allele, and no ZZ, SS or MZ individual was found in the patients. No other polymorphism was found in the sequencing results. CONCLUSION: In comparison to other populations, AAT deficiency seems not to be an important etiologic factor for neonatal cholestatic liver disease in Iran; however, further studies are recommended to estimate the true mutant gene frequencies.