Piyawan Chiengkriwate

Association of genetic polymorphisms in the RET-protooncogene and NRG1 with Hirschsprung disease in Thai patients.

Hirschsprung disease (HSCR) is a congenital developmental defect of the enteric nervous system known to be associated with the RET-protooncogene and other candidates. Recently, a genome-wide association study has added NRG1, a regulator of the development of the enteric ganglia precursors, as a new candidate gene. The aim of this study is to validate the association of the RET-protooncogene and the NRG1 in HSCR in Thai patients. The study used TaqMan single-nucleotide polymorphism (SNP) genotyping and PCR–restriction fragment length polymorphism for genotyping of 10 SNPs within the RET-protooncogene and four SNPs within the NRG1, in 68 Thai sporadic HSCR cases and 120 ethnic-matched controls. On univariate disease association analysis, 9 of 10 RET-protooncogene SNPs and all four NRG1 SNPs showed an association with HSCR. The rs2435357 (RET-protooncogene) and rs2439305 (NRG1) showed the strongest associations with the disease at P-values of 8.17E-09 (odds ratio (OR)=6.43, 95% confidence intervals (CI)=3.33–12.40) and 6.94E-03 (OR=3.28, 95% CI=1.28–8.38), respectively. The RET-protooncogene rs2435357 (TT genotype) in combination with the NRG1 rs2439305 (GG genotype) was strongly associated with an increased risk of HSCR with a P-value of 1.99E-04 (OR=20.34, 95% CI; 2.54–162.78) when compared with a single SNP of the RET-protooncogene or NRG1. Genetic variation of the RET-protooncogene and NRG1 is involved in the risk of HSCR development in the Thai population. Moreover, the study also detected a combined effect of SNPs by SNP–SNP interaction, which may help in predicting HSCR risk.

Surgery in management of snake envenomation in children

BackgroundSnakebite is common in children especially in the developing countries. This study was undertaken to determine the role of surgery in the treatment of venomous snake bite in pediatric patients.MethodsThe clinical data of 58 pediatric patients aged 0–16 years who had been treated for venomous snakebite from January 1999 to December 2008 were analyzed.ResultsOf the 58 patients, 43 (74.6%) were male. Peak age incidence was around 2–3 years (28.8%). The majority of envenomations occurred in the summer and rainy seasons, especially in the latter, during flooding. The bites occurred during 6 pm to 12 pm in 27 patients (49.0%). The main bite site was the lower extremities in 49 patients (83.9%). The main species of the snake were Malayan pit viper (Calloselasma rhodostoma) in 28 patients (47.5%) and cobra (Ophiophagus hunnah or Naja spp.) in 21 patients (35.6%). Soft tissue necrosis occurred more in cobra bites (47.6%) than viper bites (3.6%). The most common organism identified in necrotic tissue was Morganella morgagnii. Four patients with cobra bite had respiratory failure that required ventilatory support. Compartment syndrome was suspected in 2 patients. Surgical intervention was necessary in 13 patients. Most procedures involved serial wound debridement, followed by skin grafting. One case needed a toe amputation because of necrosis. The average length of hospital stay in patients who needed surgical management was 18.8 days (range: 12.1–25.5 days). There were no mortalities.ConclusionsSurgery plays an important role in the management of snakebite patients, especially for those with cobra bite with tissue necrosis.

Infectious complications in infants with gastroschisis: an 11-year review from a referral hospital in southern Thailand

UNLABELLED MAIN PURPOSES: The study aimed to (1) examine the incidence of infectious complications (ICs) in our referral hospital in southern Thailand in infants with gastroschisis, with analysis of the impact of these complications on outcomes, and (2) identify associated factors to improve the practice at our institution for dealing with this condition. METHODS A retrospective review of consecutive gastroschisis cases at the major teaching and referral hospital in southern Thailand was conducted for an 11-year period (1996-2006). Cases referred after a primary operation at other hospitals were excluded. The study focused on postoperative nosocomial infections as identified by Centers for Disease Control and Prevention criteria. RESULTS Sixty-eight patients with gastroschisis were operated on. Twenty-seven patients (39.71%) underwent primary closure. Mortality was 4 of 68 patients (5.9%). Infectious complication occurred in 43 patients (63.2%). The complications significantly increased mechanical ventilation days (10.8 vs 3.8 days in noncomplicated cases), need for parenteral nutrition (25.3 vs 14.5 days), and postoperative stay (33.7 vs 21.1 days). Common ICs were wound infection (32.35%), isolated septicemia (19.1%), and pneumonia (13.24%). Univariate analysis identified an association between the occurrence of IC and birth order (multigravida), time from birth until arrival at our center (5 hours or more), hypoalbuminemia, hypoglycemia, type of operation (staged closure), use of central venous line, and prolonged use of ventilator. On multiple logistic regression, prolonged referral time, use of a central venous line, multigravida, and staged closure independently predicted the risk of IC. CONCLUSION Infectious complication was significantly related to outcome in gastroschisis cases and should not be overlooked. Our data suggest that prompt referral, limiting central line practice on a selective basis, and an attempt to reduce wound infection in cases that require a temporary silo may improve the overall outcomes.

Novel mutation of Endothelin-B receptor gene in Waardenburg–Hirschsprung disease

Homozygous mutations of EDNRB in human have been reported to result in Waardenburg–Hirschsprung disease (WS4), while mutated heterozygotes manifested isolated Hirschsprung disease in lower penetrance. We investigated a case of WS4 together with all members of her nuclear family for the alteration of the EDNRB gene by using PCR–SSCP and direct sequencing technique. The index patient, who was born to a family with no history of Hirschsprung disease, presented total colonic aganglionosis with small bowel extension, sensorineural hearing loss and generalized cutaneous pigmentary defects. Interestingly, both irides were normally black. The study detected a homozygous missense mutation at codon 196 in exon 2 (Ser196Asn), which has not been reported. Both parents and four in six siblings harbored heterozygous mutation without any clinical manifestation. Our findings were consistent with previous observations that full spectrum of WS4 occurred to the mutate homozygotes. Moreover, the non-penetrance of heterozygotes in our pedigree, which differs from other reports, demonstrates the high pleiotropic effect of EDNRB mutations in human.

Brief communication (Original). The accuracy of the Broselow tape in the weight estimation of Thai children

Abstract Background: The effectiveness of medical treatment depends on proper drug dosing. The most accurate measurement of a child’s weight is by weighing the child on a scale, and can be done for stable children. However, an emergency, or other conditions may preclude normal weighing. The child’s weight must then be estimated quickly for treatment including drug dosages, equipment sizes, ventilator volume settings, and cardioversiondefibrillation. Objectives: To assess the accuracy of the Broselow tape in the weight estimation of Thai children. Methods: Retrospective analysis reviewing the hospital-based data of 4746 Thai children aged less than 15 years. Demographic data, measured weight (MW), and height were collected. The subjects were divided into nine color-coded groups according to the Broselow tape color range and the actual weight plotted according to their groups. Comparison between Broselow tape-predicted weight (TW), height and MW was explored. Results: A total of 3869 children met the inclusion criteria, of whom 2121 (54.8%) were male. The overall agreement between actual weight and predicted weight was 62.1% (range 36.4-90.5 depending on color-code). The mean difference between TW and MW was -3.56% (95% CI -3.964 to -3.150) with SD 12.91%, P < 0.001. TW was within a 10% error for 58% of children. Conclusions: The accuracy of the Broselow tape in the weight estimation of Thai children decreases with increasing height. The Broselow tape underestimates Thai children’s weight.

Digital camera image analysis of faeces in detection of cholestatic jaundice in infants

Background: Stool colour assessment is a screening method for biliary tract obstruction in infants. This study is aimed to be a proof of concept work of digital photograph image analysis of stool colour compared to colour grading by a colour card, and the stool bilirubin level test. Materials and Methods: The total bilirubin (TB) level contents in stool samples from 17 infants aged less than 1 year, seven with confirmed cholestatic jaundice and ten healthy subjects was measured, and outcome correlated with the physical colour of the stool. Results: The seven infants with cholestasis included 6 cases of biliary atresia and 1 case of pancreatic mass. All pre-operative stool samples in these cases were indicated as grade 1 on the stool card (stool colour in healthy infants ranges from 4 to 6). The average stool TB in the pale stool group was 43.07 μg/g compared to 101.78 μg/g in the non-pale stool group. Of the 3 colour channels assessed in the digital photographs, the blue and green light were best able to discriminate accurately between the pre-operative stool samples from infants with cholestasis and the samples from the healthy controls. With red, green, and blue (RGB) image analysis using wave level as the ANN input, the system predicts the stool TB with a relationship coefficient of 0.96, compared to 0.61 when stool colour card grading was used. Conclusion: Input from digital camera images of stool had a higher predictive capability compared to the standard stool colour card, indicating using digital photographs may be a useful tool for detection of cholestasis in infants.

Immunohistological evidence for Wnt-signaling activation in Peutz-Jeghers polyposis

ObjectiveMolecular pathogenesis of gastrointestinal polyposis in Peutz-Jegher’s syndrome (PJS) has been linked to the loss-of-function mutation of LKB1. Recent functional genetic studies have pointed out that LKB1 plays a physiological role in controlling the Wnt-signaling pathway and activation of the pathway as a consequence of LKB1 haploinsufficiency might be responsible for the development of harmatomatous polyps. This study aimed to look for immunohistochemical evidence of Wnt-signaling activation in PJS polyps.MethodBeta-catenin immunohistochemistry patterns were evaluated in gastrointestinal polyps from five cases of PJS. All patients were also evaluated for germline mutations of LKB1 and somatic mutations of beta-catenin in the polyps.ResultsFour of the five cases had germline mutations of LKB1, including two novel mutations, a one-base insertion at codon 53 and a large deletion encompassing exon 3 (codon 136–155). PJS polyps from all patients showed generalized membrane and cytoplasmic localizations of beta-catenin along the mucosal endothelium. Polyps from two cases with LKB1 mutations revealed moderate-intensity nuclear staining in approximately 20 and 70% of the polyps.ConclusionThe study offers additional evidence of Wnt-signaling activation in PJS polyp development at the tissue level, although the degree of up-regulation was not as high as has been found in Wnt-associated neoplasms.

Single nucleotide polymorphisms within Adducin 3 and Adducin 3 antisense RNA1 genes are associated with biliary atresia in Thai infants

BackgroundA genome-wide association study in East Asians suggested a genetic association between biliary atresia (BA) and a cluster of variants within the Adducin 3 (ADD3) and ADD3 antisense RNA1 (ADD3-AS1) genes. Another study in Thai neonates reported an association between BA and rs17095355. To validate those findings, this study aimed to analyze the BA association with single nucleotide polymorphisms (SNPs) and the additive influence of ADD3 and ADD3-AS1 in Thai neonates.MethodsDNAs from 56 BA cases and 166 controls were genotyped for rs2501577, rs11194981, rs12268910 (ADD3) and rs17095355 (ADD3-AS1), using TaqMan PCR. Genotype distributions were compared between the groups, and SNP–SNP interactions were analyzed by combination of allelotypes.ResultsThe risk allele frequencies of rs2501577, rs11194981, and rs17095355 in the BA group were significantly higher than in the controls. Univariate analysis showed that recessive variants in the three SNPs were associated with BA risk at ORs of 1.81 (95% CI 1.32–2.50), 1.58 (95% CI 1.14–2.20) and 1.92 (95% CI 1.39–2.66), respectively. SNP–SNP interaction analysis showed that the SNP combination of the two genes rs17095355 and rs2501577 provided an additive increase in BA risk.ConclusionADD3 and ADD3-AS1 variants increased susceptibility to BA, suggesting that these genes may play an additive role in the pathogenesis of the disease. In addition, these interactions may give a clue to the overexpression of the ADD3 protein in the liver of BA patients.

Variants Associated with Infantile Cholestatic Syndromes Detected in Extrahepatic Biliary Atresia by Whole Exome Studies: A 20-Case Series from Thailand

Biliary atresia (BA) is the most severe form of obstructive cholangiopathy occurring in infants. Definitive diagnosis of BA usually relies on operative findings together with supporting pathological patterns found in the extrahepatic bile duct. In infancy, overlapping clinical patterns of cholestasis can be found in other diseases including biliary hypoplasia and progressive familial intrahepatic cholestasis. In addition, BA has been reported as a phenotype in some rare genetic syndromes. Unlike BA, other cholangiopathic phenotypes have their own established genetic markers. In this study, we used these markers to look for other cholestasis entities in cases diagnosed with BA. DNA from 20 cases of BA, diagnosed by operative findings and histopathology, were subjected to a study of 19 genes associated with infantile cholestasis syndromes, using whole exome sequencing. Variant selection focused on those with allele frequencies in dbSNP150 of less than 0.01. All selected variants were verified by polymerase chain reaction-direct sequencing. Of the 20 cases studied, 13 rare variants were detected in 9 genes: 4 in JAG1 (Alagille syndrome), 2 in MYO5B (progressive familial intrahepatic cholestasis [PFIC] type 6), and one each in ABCC2 (Dubin-Johnson syndrome), ABCB11 (PFIC type 2), UG1A1 (Crigler-Najjar syndrome), MLL2 (Kabuki syndrome), RFX6 (Mitchell-Riley syndrome), ERCC4 (Fanconi anemia), and KCNH1 (Zimmermann-Laband syndrome). Genetic lesions associated with various cholestatic syndromes detected in cases diagnosed with BA raised the hypothesis that severe inflammatory cholangiopathy in BA may not be a distinct disease entity, but a shared pathology among several infantile cholestatic syndromes.

Sutureless elastic ring silo for the gastroschisis.

Abstract Background: The definitive surgical management of gastroschisis is the return of the eviscerated abdominal content into the abdomen as soon as possible. Objectives: Assess the efficacy of using a sutureless elastic ring silo (SERS) for the management of gastroschisis. Methods: Neonates with gastroschisis were enrolled at Songklanagarind Hospital between January 2006 and December 2008. A primary repair (PR) was attempted in all cases. If this was not possible due to concerns about abdominal compartment syndrome, a stage abdominal closure with a silo pouch was fashioned: a traditional silo (TS) or SERS. When the bowel was completely reduced, a second-stage closure was performed in the operating room. Data collected included general demographic data, size of defect, associated anomalies, hospital course, mode of gastroschisis closure, duration of parenteral nutrition (PN) and ventilator, first feeding age, complications, and length of hospital stay (LOS). Results: Twenty-nine children with gastroschisis were treated (PR: 9, TS: 9, and SERS: 11). There were no differences (p >0.05) concerning gender, mode of delivery, APGAR scores, gestational age, birth weight, or defect size. A preformed silo was employed in 20 of 29 cases, TS in nine (31%), and SERS in 11 (38%) cases in an average operative time of 80.6 and 40 minutes, respectively, a significantly shorter operative time in the SERS (p =0.007). Overall, there were no differences (p >0.05) concerning duration of ventilator support (10.2 days), duration of PN (21.3 days), first feeding age (15 days), LOS (26.5 days), and complication. Conclusion: The use of a sutureless elastic ring silo with readily available inexpensive materials is simple, safe and efficacious in our setting.