Kono-S anastomosis in Crohn's disease: initial experience in pediatric patients.

PURPOSE: Children diagnosed with Crohn's disease (CD) often undergo ileocecal resection (ICR) during childhood. Anastomotic recurrence is a frequent finding following this procedure. Data addressing the effect of the anastomosis type on disease recurrence are scarce in the pediatric population. The Kono-S anastomosis has shown promise in reducing endoscopic, clinical, and surgical recurrence rates in adults. We aimed to report our experience with Kono-S anastomosis in children, focusing on its feasibility and postoperative complications. METHODS: We retrospectively analyzed pediatric CD patients who underwent ICR with Kono-S anastomosis between August 2022 and May 2023. Data on demographics, clinical characteristics, surgery, hospitalization, and follow-up including colonoscopy were collected. Complications were classified using the Clavien-Dindo classification. RESULTS: Twelve patients (7 females, 58.3%) were included. Six (50%) of the patients had the B3 luminal form of the disease (according to Paris classification). Median surgery duration was 174 (interquartile range [IQR] 161-216) minutes. Anastomosis creation took a median of 62 (IQR, 54.5-71) minutes. Median hospitalization length was 6 (IQR 4-7) days. No short- or mid-term complications were observed. Median follow-up duration was 9.5 (IQR 6.8-12) months. CONCLUSION: According to our results, Kono-S anastomosis is safe and feasible in pediatric CD patients, with no observed postoperative complications. These findings support the potential benefit of using Kono-S anastomosis as a treatment approach in children with CD.

The comparison of magnetic resonance and fluoroscopic imaging options in the preoperative assessment of boys with anorectal malformations and a colostomy.

BACKGROUND: In recent decades, magnetic resonance imaging (MRI) has gained prominence as a standard diagnostic method for preoperative assessment in patients with anorectal malformations and a colostomy, with the potential to replace the classic fluoroscopic distal pressure colostogram (FDPC). Three MRI techniques are available: MRI-distal pressure colostogram with gadolinium (MRI-DPCG) or saline (MRI-DPCS) instillation into the colostomy and native MRI without colostomy instillation. OBJECTIVE: To evaluate and compare the diagnostic accuracy of MRI (native MRI, MRI-DPCG and MRI-DPCS) in the preoperative workup of boys with an anorectal malformation and a colostomy and to compare it to FDPC. MATERIALS AND METHODS: Sixty-two boys with preoperative MRI using one of the three approaches and 43 with FDPC met the inclusion criteria for this retrospective study. The presence and localization of rectal fistulas according to the Krickenbeck classification were evaluated and compared with intraoperative findings. RESULTS: The accuracy of fistula detection for MRI in general (regardless of the technique), MRI-DPCS, MRI-DPCG, native MRI and FDPC was 95% (59/62, P<0.001), 100% (12/12, P=0.03), 100% (30/30, P<0.001), 85% (17/20, P=0.41) and 72% (31/43, P=0.82), respectively. The accuracy of describing fistula type in patients with a correctly detected fistula using these methods was 96% (45/47, P<0.001), 100% (9/9, P<0.001), 100% (23/23, P<0.001), 87% (13/15, P<0.001) and 67% (13/21, P=0.002), respectively. CONCLUSION: MRI is a reliable method for detecting and classifying fistulas in boys with an anorectal malformation and a colostomy and can be considered the modality of first choice for preoperative workup.

Perioperative Histologically Controlled Fistula Resection in Patients with Imperforate Anus and Perineal Fistula.

INTRODUCTION: Postoperative constipation (PC) in patients with imperforate anus and perineal fistula (PF) has been reported in up to 60%. Histological studies of PF revealed innervation anomalies which seem to be one of the reasons for PC. Perioperative histologically controlled fistula resection (PHCFR) allows appropriate resection of PF and pull-down normoganglionic rectum at the time of posterior sagittal anorectoplasty (PSARP). MATERIALS AND METHODS: A total of 665 patients with anorectal malformations underwent surgery between 1991 and 2021. Of these, 364 presented PF; 92 out of them (41 F) were studied. Patients with sacral and spinal cord anomalies, neurological disorders, and cut-back anoplasty were excluded. PSARP was done on all patients. Hematoxylin-eosin staining and NADH Tetrazolium-reductase histochemical method were used. Four and more ganglion cells in the myenteric plexus represented a sufficient length of the resection. The continence was scored according to the modified Krickenbeck scoring system. Final scores ranged from 1 to 7 points. Values are given as median. RESULTS: A total of 65 (70.7%) patients presented an aganglionic segment in PF, and 27 patients presented hypoganglionosis. The median length of the resected fistula was 25 mm (interquartile range [IQR]: 20-30). The median total continence score was 7 (IQR: 6-7). Post-op constipation was observed in 6/92 (6.5%) patients. CONCLUSION: PHCFR diminished PC to 6.5% of patients.

Sexual function in adult females after feminizing genitoplasty for congenital adrenal hyperplasia.

OBJECTIVE: To investigate sexual function and subjective attitudes towards surgery in adult women after feminizing genitoplasty (FG) for congenital adrenal hyperplasia (CAH). MATERIALS AND METHODS: We retrospectively reviewed the medical files of patients who underwent FG from 1996 to 2018. Of those, patients older than 16 years of age were asked to answer non-standardized questions aiming at the awareness of genital surgery and standardized questionnaire evaluating sexual function (GRISS). The anonymized answers were compared to a control group of 50 healthy females. Student's t-test, Pearson's χ2 test, Fisher's exact test and Spearman's rank correlation coefficient were performed. A P-value less than 0.05 was considered significant. RESULTS: Out of 106 patients who underwent FG, 64 were included, 55 successfully contacted and 32, aged 17-40 years (median 25.5), answered the questionnaires (58% response rate). In all, 11 patients underwent historical clitorectomy in early childhood by a pediatric gynecologist before 1996 and pull-through vaginoplasty at puberty. A total of 21 patients underwent modern one- or two-staged FG. There were statistically significant differences between the CAH group and controls as to the proportion living in committed partnerships (28% and 84%, respectively; p = 0.0000), having sexual intercourse (41% and 92%, respectively; p = 0.0000) and having their own children (13% and 36%, respectively; p = 0.0369). The median overall GRISS score was 4 (range 1-7) in the CAH group compared to 1 (range 1-9) in the control group, with infrequency and vaginismus representing the least favorable subscales (median 5). In all, 81% of the women operated on for CAH would recommend such an operation to any other individual with CAH and 66% of them suggested the surgery should be performed in early childhood. DISCUSSION: By this study we have contributed to the debate over suggestions that FG may cause adverse effects on sexual life of the patients in adulthood, beside already published effects on their mental well-being and LUTS. Despite possible selection bias due to only 58% response rate the comparison with control group shows only a moderate sexual dysfunction and more significant impact on long-term partnership that might be caused by other factors related to CAH beside FG itself. CONCLUSIONS: Partnership, offspring, sexual frequency and function were impaired in adult females with CAH after FG. However, the median GRISS score was below the pathological level of 5.

Predictive value of tissue calprotectin for disease recurrence after ileocecal resection in pediatric Crohn's disease.

AIM: Detection of possible predictive factors of endoscopic recurrence after ileocecal resection in Crohn's disease could be very beneficial for the individual adjustment of postoperative therapy. The aim of this study was to verify, whether immunohistochemical detection of calprotectin in resection margins is useful in diagnostics of endoscopic recurrence. METHODS: In this study we included pediatric patients with Crohn's disease who underwent ileocecal resection, regardless of pre-operative or post-operative therapy (n=48). We collected laboratory, clinical, surgical, endoscopic and histopathological data at the time of surgery and at 6 months after surgery. The immunohistochemical staining of calprotectin antigen was performed on all paraffin blocks from the resection margins. RESULTS: Out of 48 patients 52% had endoscopic recurrence in the anastomosis (defined by Rutgeerts score) within 6 months after surgery. The number of cells positive for calprotectin in the proximal resection margin was negatively associated with recurrence (P=0.008), as was the elevated level of total calprotectin (from both resection margins). There was no correlation of calprotectin in distal resection margin and endoscopic recurrence. Fecal calprotectin over 100 ug/g (P=0.0005) and high CRP (P<0.001) at 6 months after ileocecal resection and peritonitis (P=0.048) were associated with endoscopic recurrence. CONCLUSION: Approximately half of the patients developed endoscopic recurrence within 6 months after ileocecal resection. The predictive value of tissue calprotectin is questionable, as it is negatively associated with endoscopic recurrence. There are other potentially useful predictors, such as CRP and fecal calprotectin at 6 months after resection and the presence of peritonitis.

Lower Urinary Tract Symptoms in Adult Females after Feminizing Genitoplasty for Congenital Adrenal Hyperplasia.

PURPOSE: We investigated quality of life, long-term lower urinary tract symptoms, sexual function and subjective attitudes toward surgery in adult women after feminizing genitoplasty for congenital adrenal hyperplasia. MATERIALS AND METHODS: We retrospectively reviewed the medical files of all patients with congenital adrenal hyperplasia who underwent feminizing genitoplasty from 1996 to 2018 in our tertiary center. Of those, patients older than 16 years of age were asked to answer 1 nonvalidated and 3 standardized and validated questionnaires evaluating their current mental well-being (WHO-5 Well-Being Index), lower urinary tract symptoms (ICIQ-FLUTS) and sexual function (GRISS). The anonymized answers of this cross-sectional study were compared to a control group of 50 healthy females. Student's t-test, Pearson's χ2 test, Fisher's exact test and Spearman's rank correlation coefficient were performed. A p-value less than 0.05 was considered significant. RESULTS: Out of 106 patients who underwent feminizing genitoplasty, 64 patients were included and 32 patients, aged 17 to 40 years (median 25.5 years), answered the questionnaires (50% response rate). The difference between congenital adrenal hyperplasia and control group mental well-being was not statistically significant (WHO-5 median score 60 and 64, respectively; p=0.82). We found no significant difference in the lower urinary tract symptoms subscales of filling, voiding or incontinence, nor in the overall lower urinary tract symptoms score (ICIQ-FLUTS overall median score 3.5 and 3, respectively; p=0.43). CONCLUSIONS: We found in our group no abnormal mental well-being or prevalence of long-term symptoms of lower urinary tract dysfunction in adult female patients with congenital adrenal hyperplasia following feminizing genitoplasty.

The Impact of Anti-Tumor Necrosis Factor Alpha Therapy on Postoperative Complications in Pediatric Crohn's Disease.

INTRODUCTION: The incidence of Crohn's disease (CD) within the pediatric population is increasing worldwide. Despite a growing number of these patients receiving anti-tumor necrosis factor α therapy (anti-TNF-α), one-third of them still require surgery. There is limited data as to whether anti-TNF-α influences postoperative complications. We evaluated postoperative complications in patients who were or were not exposed to anti-TNF-α therapy in our institutional cohort. MATERIALS AND METHODS: A retrospective review of CD patients who underwent abdominal surgery between September 2013 and September 2018 was performed. The patients were divided into two groups based on whether they were treated with anti-TNF-α within 90 days before surgery. Thirty-day postoperative complications were assessed using Clavien-Dindo classification (D-C); this examination included surgical site infections (SSIs), stoma complications, intra-abdominal septic complications, non-SSIs, bleeding, ileus, readmission rate, and return to the operating room. Mann-Whitney U-test, Fisher's exact test, and multivariate logistic regression analyses were used for statistical analysis. RESULTS: Sixty-five patients (41 males) with a median age of 16 years (range: 7-19) at the time of operation were identified. The most common surgery was ileocecal resection in 49 (75%) patients. Forty-three (66.2%) patients were treated with anti-TNF-α preoperatively. Seven patients (11%) experienced postoperative complications. There was no statistically significant difference in postoperative complication in patients who did or did not receive anti-TNF-α before surgery (D-C minor 2.3% vs. 4.6%, p = 1; D-C major 7% vs. 9.1%, p = 1). CONCLUSION: The use of anti-TNF-α in pediatric CD patients within the 90 days prior to their abdominal surgery was not associated with an increased risk of 30-day postoperative complications.

Endoscopic Recurrence 6 Months After Ileocecal Resection in Children With Crohn Disease Treated With Azathioprine.

OBJECTIVES: Intestinal surgery is an important part of Crohn disease (CD) treatment in children. The aim of the present study was to compare the rate of endoscopic recurrence at the sixth month after ileocecal resection (ICR) in children with CD treated with azathioprine between patients who received prior antitumor necrosis factor alpha (anti-TNF-α) therapy and those who were not administered this therapy. Moreover, we tried to identify the potential risk factors for disease recurrence and describe the schedule of long-term follow-up after surgery. METHODS: We prospectively collected data from pediatric patients with CD, who underwent ICR between October 2011 and June 2015 at our hospital and were treated with azathioprine monotherapy after ICR. We evaluated the endoscopic recurrence (Rutgeerts score) at the sixth month after ICR in all included patients. RESULTS: Among 21 included patients, 13 achieved endoscopic remission (Rutgeerts score < i2) at the sixth month after ICR. No difference was found between patients who received prior anti-TNF-α therapy and those who did not. We did not find any clinically relevant factors associated with endoscopic recurrence rate at the sixth month. CONCLUSIONS: Prior anti-TNF-α therapy does not seem to be a strong risk factor for endoscopic recurrence within 6 months after ICR. Further studies on large sample of patients are needed to identify potential predictors of disease recurrence.

Pediatric Bulbar and Posterior Urethral Injuries: Operative Outcomes and Long-Term Follow-Up.

AIM: The aim of this study was to analyze complications and outcomes of end-to-end urethral anastomosis performed for posttraumatic bulbar strictures or posterior urethral injuries in pediatric patients. METHODS: The records of 15 boys, age 18 years and below, admitted to our tertiary trauma center with urethral injuries from 1989 to 2014 were reviewed retrospectively. Out of these 15 boys, 7 were excluded (2 for iatrogenic trauma, 2 for minor straddle injuries who were not operated on, 2 for incomplete records, and 1 lost to follow-up) and 8 analyzed patients were operated for bulbar or posterior urethral injury. The mean follow-up after the operation was 4.5 years (range 0.5-10). To obtain up-to-date follow-up information, all the analyzed patients were contacted by a letter and telephone in January 2015 and asked about lower urinary tract or erectile dysfunction (ED) using the International Index of Erectile Function-5 questionnaire. RESULTS: Mean age at the time of injury was 12.3 years (range 5-17). Four patients with pelvic fracture had complete posterior urethra disruption, three patients after straddle injury developed obliterating stricture of the bulbar urethra and one patient had torn his bulbar urethra apart by a sharp hook. Except for the immediate exploration of the open perineal wound, all patients were operated via perineal approach 1 to 6 months after initial suprapubic catheter insertion. Five patients needed a cystotomy to identify the proximal urethral stump by a probe, and two patients had partial pubectomy to gain urethral length. Postoperative complications included stricture in anastomosis in six patients (all reoperated, four more than once including attempts of endoscopic internal urethrotomy). Six days after surgery, one patient developed massive external bleeding around a permanent urinary catheter due to a posttraumatic ruptured arterial aneurysm that was later stopped by urgent angiography and coil insertion. After discharge, three patients had transient stress incontinence. All patients had uroflowmetry maximum flow above 20 mL/s on their last follow-up except for two (12 and 15 mL/s). None have any lower urinary tract dysfunction symptoms in adulthood; one suffers from mild ED and two report moderate ED due to penile shortening. CONCLUSION: Delayed end-to-end anastomosis for pediatric urethral injury is a safe operational option. However, high rate of short-term complications and reoperations should be expected. Penile shortening is one of the most severe long-term complications.

Abnormalities in pulmonary function in infants with high-risk congenital diaphragmatic hernia.

AIMS: The aim of the study was to analyze lung growth and abnormality of infant pulmonary function tests (IPFT) in congenital diaphragmatic hernia (CDH) survivors younger than three years of age with respect to unfavorable prognostic factors. METHODS: Thirty high-risk CDH survivors at the age of 1.32±0.54 years, body weight 9.76±1.25 kg were examined using IPFT: tidal breathing analysis, baby resistance/compliance, whole baby body plethysmography and rapid thoraco-abdominal compression. Gore-Tex patch was used in 13% of patients (GORE group). Pulmonary hypertension was diagnosed and managed in 13% (iNO group). Standard protocols and appropriate reference values were used and obtained data were statistically analysed. RESULTS: High incidence of peripheral airway obstruction (70%), increased value of functional residual capacity (FRCp) 191.3±24.5 mL (126.5±36.9 % predicted; P < 0.0005), increased value of effective airway resistance (Reff) 1.71±0.93 kPa.L(-1).s (144.4±80.1 % predicted; P < 0.01) and decreased specific compliance of the respiratory system (Crs/kg) 14.1±2.3 mL.kPa.kg(-1) (i.e., 76.1±20.1 % predicted, P < 0.0005) was noted in infants with CDH in comparison with reference values. Increased value of FRCp was found in GORE group (165.7±51.9 versus 120.4±31.2, P < 0.02) and in iNO group (183.1±52.6 versus 117.8±25.7 mL; P < 0.0005). CONCLUSION: A high incidence of peripheral airway obstruction, an increased value of FRCp and decreased specific compliance of the respiratory system was noted in infants with CDH. Unfavorable prognostic factors (Gore-Tex patch, pulmonary hypertension) correlate with more severe alteration of pulmonary function in infants.

Long-term outcomes after elective ileocecal resection in children with active localized Crohn's disease--a multicenter European study.

PURPOSE: The aim of this study was to investigate the therapeutic role of an elective ileocecal resection in children with active localized Crohn's disease. METHODS: This was a retrospective multicenter study which included five European referral centers which included all children with Crohn's disease who underwent ileocecal surgery from 2000 to 2011 and had a minimum of 12 months follow-up. RESULTS: Altogether 68 patients fulfilled inclusion criteria. Median age at diagnosis was 13.7 years (6.6-17.9 years) and at surgery 15.2 years (8.6-18.5 years). Median duration of postoperative clinical remission was 20 months (3-95 months). Overall 54 patients (79.4%) were in remission one year after surgery and 38 (55.9%) during the total postsurgical follow up (median 30 months; range 12-95 months). Z score height for age significantly improved postoperatively in children who were at the time of surgery younger than 16 years of age (mean difference 0.232 SD; p=0.029). Cox proportional hazard regression model failed to indicate risk factors associated with postsurgical relapse. CONCLUSION: Elective ileocecal resection is a valid treatment option which should be considered in a subset of pediatric patients with localized Crohn's disease with the aim of achieving clinical remission and to improve growth.

RET variants and haplotype analysis in a cohort of Czech patients with Hirschsprung disease.

Hirschsprung disease (HSCR) is a congenital aganglionosis of myenteric and submucosal plexuses in variable length of the intestine. This study investigated the influence and a possible modifying function of RET proto-oncogene's single nucleotide polymorphisms (SNPs) and haplotypes in the development and phenotype of the disease in Czech patients. Genotyping of 14 SNPs was performed using TaqMan Genotyping Assays and direct sequencing. The frequencies of SNPs and generated haplotypes were statistically evaluated using chi-square test and the association with the risk of HSCR was estimated by odds ratio. SNP analysis revealed significant differences in frequencies of 11 polymorphic RET variants between 162 HSCR patients and 205 unaffected controls. Particularly variant alleles of rs1864410, rs2435357, rs2506004 (intron 1), rs1800858 (exon 2), rs1800861 (exon 13), and rs2565200 (intron 19) were strongly associated with increased risk of HSCR (p<0.00000) and were over-represented in males vs. females. Conversely, variant alleles of rs1800860, rs1799939 and rs1800863 (exons 7, 11, 15) had a protective role. The haploblock comprising variants in intron 1 and exon 2 was constructed. It represented a high risk of HSCR, however, the influence of other variants was also found after pruning from effect of this haploblock. Clustering patients according to genotype status in haploblock revealed a strong co-segregation with several SNPs and pointed out the differences between long and short form of HSCR. This study involved a large number of SNPs along the entire RET proto-oncogene with demonstration of their risk/protective role also in haplotype and diplotype analysis in the Czech population. The influence of some variant alleles on the aggressiveness of the disease and their role in gender manifestation differences was found. These data contribute to worldwide knowledge of the genetics of HSCR.

The diagnostic value of MRI fistulogram and MRI distal colostogram in patients with anorectal malformations.

Contrast fistulogram (FG) and distal pressure colostogram (DPCG) are standard diagnostic methods for the assessment of anorectal malformations. Pelvic magnetic resonance imaging (MRI) earned a place among essential diagnostic methods in preoperative investigations after the Currarino syndrome and a high incidence of associated spinal dysraphism were described. The aim of our study was to evaluate the possibility of substituting FG and DPCG by a modified pelvic MRI, e.g. MRI fistulogram (MRI-FG) and MRI colostogram (MRI-DPCG). The prospective study involved 29 patients with anorectal malformations who underwent a modified pelvic MRI. The length and course of fistulas and rectum, and the presence of sacral anomalies were studied on MRI images and compared with images obtained by radiologic examinations. Modified MRI brought identical results as contrast studies in 25 patients when related to the fistula and rectum length and course. MRI was more accurate for the detection of sacral anomalies. MRI-FG was the only imaging method used in the four most recent patients. The results support the assumption that conventional contrast examinations for the assessment of anorectal malformations can be replaced by MRI, thus reducing the radiation dose.

Hirschsprung's disease and medullary thyroid carcinoma: 15-year experience with molecular genetic screening of the RET proto-oncogene.

PURPOSE: Inactivating germline mutations in the RET proto-oncogene are the major genetic cause of Hirschsprung's disease (HD). In some cases, HD can be associated with medullary thyroid carcinoma (MTC) that is commonly caused by activating RET mutations. METHODS: The retrospective and prospective genetic analyses of 157 patients with HD operated on between December 1979 and June 2011 were carried out. DNA was isolated from peripheral leukocytes. HD patients and family members were tested for RET mutations by direct sequencing and single-strand conformation polymorphism methods. RESULTS: RET mutations were detected in 16 patients (10%). Association with MTC was found in two families, other eight families had a mutation with potentially high risk of MTC development and four novel mutations were detected. Total colonic aganglionosis was noted to have a high mutation detection rate (40%). Three patients underwent total thyroidectomy (two had clinical manifestation of MTC, one C-cell hyperplasia). CONCLUSION: Results show the benefit of systematic RET mutation screening in HD patients in order to identify the risk of MTC in the preclinical stage of the disease. All patients should be tested for RET mutations at least in exon 10, and now additionally in exon 11 and 13, as well.

Influence of anesthesia on the results of intraoperative diagnostic electromyostimulation in patients with anorectal malformation.

BACKGROUND AND PURPOSE: Stimulation electromyography (sEMG) is useful in identifying the sphincter muscle (M) in patients with anorectal malformations (ARMs). This study evaluates the effect of anesthetic agents and M relaxants on sEMG findings. MATERIALS AND METHODS: Seventeen infants (10 boys and 7 girls) with a mean age of 6.3 months and mean body weight of 6.7 kg were included in a prospective randomized study. Anesthesia was induced by sevoflurane and opioids, and an epidural catheter was inserted caudally. Stimulation electromyography of levator ani M using 14 mA current was used, and latency and amplitude of the evoked compound M action potential (CMAP) were recorded. Patients were randomized into 2 groups. Group A received a local anesthetic epidurally, and sEMG was performed. Administration of the M relaxant and measurement of M response followed. In group B drug administration, sEMG and response measurement were performed after administration of M relaxant. RESULTS: Baseline CMAP was recorded in all patients. Average latency was 4.1 milliseconds, and average amplitude was 0.43 mV. In group A, the average latency was 4.0 milliseconds, and average amplitude was 0.65 mV. After administration of the M relaxant, the CMAP disappeared. In group B, no CMAP was observed immediately after administration of the M relaxant. CONCLUSION: Administration of the inhalational anesthetic, opioids, and local anesthetic did not influence the M response of M fibers in the levator ani M on sEMG and enables its localization during ARM reconstruction. Nondepolarizing M relaxation completely abolished the response. If M relaxant is necessary, cisatracurium is used. The most suitable method of anesthesia for ARM surgery appears to be inhalational anesthesia supplemented by opioids and epidural analgesia.

RET mutation Tyr791Phe: the genetic cause of different diseases derived from neural crest.

Activating germline RET mutations are presented in patients with familial medullary thyroid carcinoma (FMTC) and multiple endocrine neoplasia (MEN) types 2A and 2B, whereas inactivating germline mutations in patients with Hirschsprung's disease (HSCR). The aim of this study was to evaluate genotype-phenotype correlations of the frequently discussed Tyr791Phe mutation in exon 13 of the RET proto-oncogene. Screening of three groups of patients was performed (276 families with medullary thyroid carcinoma (MTC), 122 families with HSCR, and 29 patients with pheochromocytoma). We found this mutation in 3 families with apparently sporadic MTC, 3 families with FMTC/MEN2, 1 patient with pheochromocytoma, and 3 families with HSCR. All gene mutation carriers have a silent polymorphism Leu769Leu in exon 13. In three families second germline mutations were detected: Cys620Phe (exon 10) in MEN2A family, Met918Thr (exon 16) in MEN2B family, and Ser649Leu (exon 11) in HSCR patient. Detection of the Tyr791Phe mutation in MEN2/MTC and also in HSCR families leads to the question whether this mutation has a dual character (gain-of-function as well as loss-of-function). A rare case of malignant pheochromocytoma in a patient with the Tyr791Phe mutation is presented. This study shows various clinical characteristics of the frequently discussed Tyr791Phe mutation.

The risk of medullary thyroid carcinoma in patients with Hirschsprung's disease.

Hirschsprung's disease (HD) can be associated with the development of neuroendocrine tumours such as medullary thyroid carcinoma (MTC). The RET proto-oncogene is the major gene responsible for both HD and MTC. Mutations in exon 10 (codons 609, 611, 618, 620) were found in patients with co-occurrence of HD and MTC. The aim of the study was to screen the MTC risk in patients with HD. The prospective and retrospective genetic analyses comprised 56 HD patients (41 males, 15 females, aged 0-47). The prospective subgroup of patients consisted of 34 patients (25 boys, 9 girls) operated on between June 2003 and December 2005. The retrospective subgroup comprised 22 patients (16 boys, 6 girls) of 194 patients who were operated on between December 1979 and May 2003, non-systematically chosen preferably for total colonic aganglionosis (TCA). DNAs were isolated from blood and resected segments of aganglionic bowel. The HD patients and nine available family members (2 HD) were tested for RET mutations in exons 10, 11, 13, 14, 15 and 16. Direct double-stranded fluorescent sequencing revealed typical germline heterozygous MTC risk RET mutations in 3/56 (5.4%) female HD patients: Cys609Tyr, Cys620Arg (both exon 10) and Tyr791Phe (exon 13). Two of these patients had TCA and one patient had classical type of HD. One TCA patient developed clinical stage of MTC and underwent total thyroidectomy (TTE). The other two RET positive HD patients (aged 7 and 25 years) are screened for calcitonin level and they are without TTE till now. Two family members (mothers of TCA patients) with detected RET mutation underwent prophylactic TTE with MTC finding. Results showed the benefit of systematic RET mutation screening in HD patients in order to identify the risk of MTC in preclinical stage of the disease in patients with HD and their family members. We recommend to investigate not only exon 10 but also exon 13.

Intestinal neuronal dysplasia.

Intestinal neuronal dysplasia type B (IND B) is currently defined as a disease of the submucous plexus of the intestine. The aetiology of IND B remains largely obscure. The congenital origin of IND B is supposed; nevertheless, the findings of IND B associated with chronic intestinal obstruction support the notion that this disease could be caused by a reaction of the enteral nervous system to intestinal obstruction or inflammatory disease either in the fetal or the postnatal period. The treatment of IND type B has no unified concept of treatment. The ultimate clinical diagnosis of IND B should be based on a definitive histological diagnosis relating to clinical symptoms, the course of treatment and long-term follow-up of patients with this dysfunction of intestinal motility, despite the fact that no correlations of the clinical picture, radiological investigation and anorectal manometric studies with IND B have been found so far.

A novel Czech kindred with familial medullary thyroid carcinoma and Hirschsprung's disease.

PURPOSE: The RET proto-oncogene is involved in neural crest disorders. Activating germline mutations in the RET proto-oncogene cause the development of familial medullary thyroid carcinoma (FMTC) or medullary thyroid carcinoma (MTC) as a part of multiple endocrine neoplasia type 2 (MEN2) syndrome. Inactivating germline mutations in the RET proto-oncogene are detected in Hirschsprung's disease (HSCR). Only in a very small number of families are these 2 diseases expressed together. METHODS: This study presents a novel Czech kindred with FMTC-HSCR phenotype. Two family members (mother and daughter) were tested for RET germline mutations in exons 10, 11, 13, 14, 15, and 16. RESULTS: Direct fluorescent sequencing of genomic DNA revealed a heterozygous mutation in the RET proto-oncogene in exon 10 at codon C609Y in both persons tested. This family was reclassified, thanks to genetic screening from the apparently sporadic MTC-HSCR to FMTC-HSCR. CONCLUSION: The germline mutation was detected because of the systematic genetic screening of the RET proto-oncogene, which is useful for genetic counseling of potential risk of HSCR and MTC in other family members. This family could be added to the small worldwide cohort of families with MEN2A/FMTC-HSCR.