Association between Fecal Calprotectin and Mucosal Healing in Pediatric Patients with Crohn's Disease Who Have Achieved Sustained Clinical Remission with Anti-Tumor Necrosis Factor Agents

Background/Aims

Although mucosal healing (MH) is acknowledged as the treatment target in the treat-to-target era, there are limitations on repeated endoscopic examinations, especially in pediatric patients. We aimed to investigate whether fecal calprotectin (FC) could serve as a surrogate marker for the assessment of MH in pediatric patients with Crohn’s disease (CD) who have achieved sustained clinical remission (CR) while treated with anti-tumor necrosis factor (TNF) agents.

Methods

This multicenter retrospective cross-sectional study included pediatric CD patients who had sustained a CR for at least 6 months with anti-TNF agents and who simultaneously underwent ileocolonoscopy and FC tests during follow-up. MH was defined as the absence of any ulcer on ileocolonoscopy.

Results

A total of 131 patients were included in this study. MH was observed in 87 patients (66.7%). The FC level was significantly lower in patients with MH than in those without MH (median 49.0 mg/kg vs 599.0 mg/kg; p<0.001). According to the multivariate logistic regression analysis, FC was the only factor associated with MH (odds ratio, 0.62; 95% confidence interval [CI], 0.52 to 0.73; p<0.001). According to the receiver operating characteristic curve analysis, the optimal cutoff value for FC for the association with MH was <140 mg/kg (area under the curve 0.890, 95% CI 0.829 to 0.951, sensitivity 78.2%, specificity 88.6%, p<0.001).

Conclusions

FC was associated with MH in pediatric patients with CD who had achieved a sustained CR for at least 6 months with anti-TNF agents. In these patients, FC can be used to stratify patients and guide decisions regarding ileocolonoscopy in the treat-to-target era.

Individual approach for treatment of primary intestinal lymphangiectasia in children: single-center experience and review of the literature

Background

Intestinal lymphangiectasia is a rare disease. Thus, prospective studies are impossible, and therapy is still controversial. Several medicines are suggested for treatment but there are no existing indications for drug choice and treatment guidelines. We aimed to introduce the action mechanism of each drug and treatment overview in a single-center experience and a review of the literature on second-line therapy for primary intestinal lymphangiectasia.

Method

Children under 18 years old diagnosed with intestinal lymphangiectasia from June 2000 to June 2020 were included and retrospectively reviewed in the study. Capsule endoscopy, MR lymphangiography, or whole-body MRI for investigating the extent of abnormal lymphatic vessels in addition to endoscopy and biopsy were conducted. The individual treatment approaches depended upon the lymphangiectasis locations involved.

Results

Only one patient showed a response to dietary therapy. One patient was successfully cured after two therapeutic lymphatic embolization. Octreotide was tried for two patients who had extensive lymphangiectasis. Lymphangiectasis recurred when octreotide was used for 3 months in one patient, and there was no effect in the other patient. Sirolimus was tried for four patients. Two of them had abnormal lymphatic lesions only in the intestine, and the others had extensive lymphangiectasis. The former group showed clinical improvement after 3–4 months of sirolimus treatment, whereas the latter group showed clinical improvement only after 1 month of sirolimus treatment.

Conclusion

Surgery or embolization is a potential therapeutic option for patients with focal abnormal lymphatic lesions. Octreotide is not an optimal choice for patients with extensive lymphangiectasis. Sirolimus is an effective and safe drug and can be the first drug of choice for patients with extensive lymphangiectasis.

The Identification of a Novel Thiopurine S-Methyltransferase Allele, TPMT*45, in Korean Patient with Crohn's Disease

Pediatric Crohn’s disease (CD) carries a higher genetic susceptibility and an increased risk of a more aggressive disease course than adult CD. Treatment of CD is based on immunomodulatory drugs, such as thiopurines. The enzyme mainly involved in drug metabolism is thiopurine S-methyltransferase (TPMT). An increased concentration of drug metabolites can cause adverse drug effects, such as myelosuppression and hepatotoxicity; therefore, assessing the activity of TPMT is essential both before and during treatment. TPMT genotyping result is not affected by previous thiopurine dose and currently is the primary component of TPMT activity and disease monitoring. Until now, more than 40 allelic variants of the TPMT gene have been reported, with most of them having an uncertain or no enzyme function. In this article, we report the first case of a novel TPMT allele, TPMT*45, that was identified in a Korean girl with CD whose findings suggested decreased TPMT activity. This newly observed variant is caused by a single nucleotide polymorphism resulting in nonsense mutation (c.676C>T, p.R226*) and the partial loss of amino acids in the TPMT protein. Initially, the patient began azathioprine at a standard dosage (1.5 mg/kg/day), and her laboratory results, including red blood cell (RBC) TPMT activity (6-methylmercaptopurine 2.68 nmol/mL/h and 6-methylmercaptopurine riboside 4.82 nmol/mL/h) along with thiopurine metabolite levels (6-thioguanine nucleotides 479.3 pmol/8×10⁸ RBC), suggested an enzyme deficiency. The thiopurine dose was reduced to half (0.7 mg/kg/day), and the follow-up metabolite results as well as the associated inflammatory markers were continuously within reference ranges. Along with an improvement in the patient’s subjective reports and clinical symptoms, the patient demonstrated a good treatment response to the adjusted dose. The results of our report illustrate the importance of TPMT genotyping and pharmacogenetic-based thiopurine dose adjustment. Further research should focus on the functional characterization and impact on this novel allele’s treatment effect.

Pediatric Crohn's disease with severe morbidity manifested by gastric outlet obstruction: two cases report and review of the literature

Crohn’s disease (CD) presenting as gastric outlet obstruction is rare but serious clinical presentation of CD causing severe morbidity. However, there have been few case reports concerning this disorder in East Asian children and adolescents. The current case report describes 2 pediatric patients with CD who had had gastric outlet obstruction as an initial symptom of CD. Two pediatric patients developed postprandial vomiting, bloating, and unintentional weight loss. The upper endoscopy result indicated that there was pyloric obstruction with mucosal edema, inflammation and ulcers. The serologic test and colonoscopy results suggested CD. These patients were treated with infliximab, and endoscopic balloon dilation without surgery and showed remarkable improvement in obstructing symptoms with maintaining clinical and biochemical remission. This case report elucidates the benefits of early intervention using infliximab and endoscopic balloon dilation to improve gastric outlet obstruction and achieve baseline recovery in patients with upper gastrointestinal B2 phenotype of CD.

Delayed Establishment of Gut Microbiota in Infants Delivered by Cesarean Section

The maternal vaginal microbiome is an important source for infant gut microbiome development. However, infants delivered by Cesarean section (CS) do not contact the maternal vaginal microbiome and this delivery method may perturb the early establishment and development of the gut microbiome. The aim of this study was to investigate the early gut microbiota of Korean newborns receiving the same postpartum care services for two weeks after birth by delivery mode using fecal samples collected at days 3, 7, and 14. Early gut microbiota development patterns were examined using 16S rRNA gene-based sequencing from 132 infants either born vaginally (VD, n = 64) or via Cesarean section (CS, n = 68). VD-born neonates showed increased alpha diversity in infant fecal samples collated at days 7 and 14 compared to those from day 3, while those of CS infants did not differ (p < 0.015). Bacterial structures of infants from both groups separated at day 7 (p < 0.001) and day 14 (p < 0.01). The bacterial structure of VD infants gradually changed over time (day 3 vs. day 7, p < 0.012; day 3 vs. day 14, p < 0.001). Day 14 samples of CS infants differed from day 3 and 7 samples (day 3 vs. day 14, p < 0.001). VD infant relative abundance of Bifidobacterium (days 7, 14), Bacteroides (days 7, 14), and Lachnospiraceae (day 7) significantly increased compared to CS infants, with a lower abundance of Enterobacteriaceae (found in all periods of the CS group) (LDA > 3.0). Relative abundances of Bifidobacterium, Lactobacillus, and Staphylococcus were significantly increased in both VD and CS groups at day 14 (LDA > 3.0). Predicted functional analysis showed that VD infants had overrepresented starch/sucrose, amino acid and nucleotide metabolism in gut microbiota with depleted lipopolysaccharide biosynthesis until day 14 compared to CS infants. This study confirmed that delivery mode is the major determinant of neonatal intestinal microbiome establishment and provides a profile of microbiota perturbations in CS infants. Our findings provide preliminary insight for establishing recovery methods to supply the specific microbes missing in CS infants.

Adjustment of azathioprine dose should be based on a lower 6-TGN target level to avoid leucopenia in NUDT15 intermediate metabolisers

BACKGROUND

The association between NUDT15 polymorphisms and thiopurine-induced leucopenia is well known.

AIM

To investigate the association between NUDT15 polymorphisms and time-to-leucopenia in paediatric patients with inflammatory bowel disease (IBD) receiving azathioprine and to determine the relationship between NUDT15 polymorphisms and 6-thioguanine nucleotide (6-TGN) levels.

METHODS

This retrospective observational study included Korean paediatric patients with IBD who were treated with azathioprine and underwent NUDT15 and TPMT genotyping. Azathioprine doses were adjusted by regular thiopurine metabolite monitoring. Factors associated with time-to-leucopenia and the relationship between NUDT15 polymorphisms and 6-TGN levels were analysed.

RESULTS

Among the 167 patients included, leucopenia was observed in 16% (19/119), 44% (20/45) and 100% (3/3) of the NUDT15 normal, intermediate and poor metabolisers respectively (P < 0.001). NUDT15 polymorphism was significantly associated with time-to-leucopenia (HR = 5.26, 95% CI = 2.74-10.09, P < 0.001). There was a positive association between 6-TGN levels and leucopenia among the NUDT15 intermediate/TPMT normal metabolisers (median 361.3 vs 263.8 pmol/8 × 10⁸ RBC, P = 0.013). The most accurate 6-TGN cut-off level associated with leucopenia was 308.2 pmol/8 × 10⁸ RBC (AUC = 0.742, 95% CI = 0.569-0.915, sensitivity 80.0%, specificity 72.7%, P < 0.001) in this subgroup. When the specificity was set to <15%, the 6-TGN cut-off level was 167.1 pmol/8 × 10⁸ RBC (sensitivity 93.3%, specificity 13.6%).

CONCLUSIONS

NUDT15 polymorphisms were associated with time-to-leucopenia during azathioprine treatment in Korean paediatric patients with IBD. In order to reduce the development of thiopurine-induced leucopenia (<15%) in NUDT15 intermediate metabolisers, adjustment of azathioprine doses should be based on a lower 6-TGN target level (<167.1 pmol/8 × 10⁸ RBC).

Successful Sirolimus Treatment for Korean Patients with Activated Phosphoinositide 3-kinase δ Syndrome 1: the First Case Series in Korea

Activated phosphoinositide 3-kinase δ syndrome (APDS)1 is caused by gain-of-function mutations in PIK3CD, which encodes the catalytic p110δ subunit of phosphoinositide 3 kinase. We describe three patients with APDS1, the first thereof in Korea. Therein, we investigated clinical manifestations of APDS1 and collected data on the efficacy and safety profile of sirolimus, a mammalian target of rapamycin inhibitor and pathway-specific targeted medicine. The same heterozygous PIK3CD mutation was detected in all three patients (E1021K). After genetic diagnosis, all patients received sirolimus and experienced an excellent response, including amelioration of lymphoproliferation and improvement of nodular mucosal lymphoid hyperplasia in the gastrointestinal tract. The median trough level of sirolimus was 5.5 ng/mL (range, 2.8-7.5) at a dose of 2.6-3.6 mg/m². Two patients who needed high-dose, short-interval, immunoglobulin-replacement treatment (IGRT) had a reduced requirement for IGRT after initiating sirolimus, and the dosing interval was extended from 2 and 3 weeks to 4 weeks. The IgG trough level after sirolimus treatment (median, 594 mg/dL; range, 332-799 mg/dL) was significantly higher than that before sirolimus treatment (median, 290 mg/dL; range, 163-346 mg/dL) (p<0.001). One episode of elevated serum creatinine with a surge of sirolimus (Patient 2) and episodes of neutropenia and oral stomatitis (Patient 1) were observed. We diagnosed the first three patients with APDS1 in Korea. Low-dose sirolimus may alleviate clinical manifestations thereof, including hypogammaglobulinemia.

Myositis as an Initial Presentation of Ulcerative Colitis before Gastrointestinal Symptoms

The musculoskeletal system can be involved as an extra-intestinal manifestation of inflammatory bowel disease. Among these, myositis in ulcerative colitis (UC) is very rare. A 14-year-old girl was admitted due to severe shoulder tenderness. She had complained of left jaw pain and swelling for the past 10 days. Inflammatory markers were elevated with no evidence of infectious etiology. Myositis was suspected by shoulder magnetic resonance imaging. Three days after admission, she developed hematochezia. Muscle biopsy and colonoscopy was performed due to worsening left mandibular area pain and persistent hematochezia. Colonoscopy showed consistent findings with UC. She was finally diagnosed with UC with myositis as an extra-intestinal manifestation. She showed a dramatic response to UC treatment. Gastrointestinal symptoms were well-controlled. After 14 months, UC symptoms and muscle pain were aggravated, which were relieved after steroid and cyclosporin treatment. We report a unique case of UC initially presented with myositis, preceding gastrointestinal symptoms.

Potential Utility of Therapeutic Drug Monitoring of Adalimumab in Predicting Short-Term Mucosal Healing and Histologic Remission in Pediatric Crohn's Disease Patients

BACKGROUND

Limited data exist regarding mucosal healing (MH) and therapeutic drug monitoring (TDM) in pediatric Crohn's disease (CD) patients treated with adalimumab (ADL). We aimed to investigate the associations between ADL trough levels (TLs) and MH, and between ADL TLs and histologic remission (HR) at 16 weeks from ADL treatment in pediatric CD patients.

METHODS

This was a prospective study on moderate-to-severe luminal pediatric CD patients receiving ADL. Ileocolonoscopies and biopsies, as well as clinical activity assessments, laboratory examinations, including tests for ADL TLs and antibody to ADL, were performed 16 weeks after ADL initiation. MH was defined as a Simple Endoscopic Score for CD of 0. HR was defined as the complete absence of microscopic inflammation.

RESULTS

Seventeen subjects (13 males, 4 females) were included. At 16 weeks from ADL initiation, 14 (82.4%), 8 (47.1%), and 4 (23.5%) patients achieved clinical remission, MH, and HR, respectively. ADL TLs were significantly higher in patients who achieved MH compared to those who did not (13.0 ± 6.5 vs. 6.2 ± 2.6 μ/mL, respectively; P = 0.023) and also significantly higher in patients who achieved HR compared to those who did not (17.9 ± 5.3 vs. 6.8 ± 2.5 μ/mL, respectively; P = 0.02). The optimal TL for predicting MH was 8.76 μ/mL.

CONCLUSION

Serum ADL TLs at 16 weeks were significantly higher in pediatric patients with CD who achieved MH and HR, respectively. TDM may guide in optimizing treatment efficacy and better target MH in the era of treat-to-target.

Serum Infliximab Cutoff trough Level Values for Maintaining Hematological Remission in Pediatric Inflammatory Bowel Disease

Background/Aims

Infliximab (IFX) often loses its therapeutic effect in initial responders with inflammatory bowel disease (IBD) over time. Low serum IFX trough levels (TLs) are linked to poor clinical response and outcomes. Maintenance of optimal therapeutic IFX concentrations is important for sustaining response and achieving good clinical outcomes. Measurement of serum IFX TLs is helpful for determining a further proper therapeutic plan. However, adequate therapeutic IFX TLs in pediatric IBD is uncertain. We aimed to identify the cutoff values for IFX TLs associated with laboratory response to IFX maintenance therapy.

Methods

Patients with pediatric IBD who had received IFX infusions between December 2008 and March 2015 at Samsung Medical Center were retrospectively investigated. We analyzed 239 blood samples that were collected from 103 pediatric patients. We measured IFX TLs at induction (6 and 14 weeks) and during maintenance therapy (>22 weeks, 8 weeks interval) by fluid-phase radioimmunoassays.

Results

A significant association was found between the erythrocyte sedimentation rate (ESR) and IFX TLs during maintenance (correlation coefficient, -0.11; p=0.0005). A cutoff value of 18 mm/hr for ESR was used to define higher levels. Receiver operating characteristic analysis identified optimal cutoff values: IFX TL >1.58 µg/mL (sensitivity 82% and specificity 73%).

Conclusions

Cutoff values are considered a prerequisite for further investigating the clinical usefulness of measurements of IFX in patients maintained with IFX treatment.

Development and Validation of the Mucosal Inflammation Noninvasive Index For Pediatric Crohn's Disease

BACKGROUND & AIMS

Mucosal healing (MH) has become a goal of therapy for Crohn's disease (CD), but frequent endoscopies are not feasible. We aimed to develop and validate a non-invasive index to assess mucosal inflammation in children with CD.

METHODS

We collected data from the multi-center prospective ImageKids study, in which children with CD underwent ileocolonoscopy with magnetic resonance enterography. We investigated the association of pediatric CD activity index (PCDAI) items and laboratory test results with the simple endoscopic score for CD (SESCD). We used these data in a blended mathematical judgmental clinimetric approach to develop a weighted categorized index to identify children with CD who have MH, which we called the MINI index. We validated the index using data from 3 independent patient cohorts. The derivation and validation cohorts included 154 and 168 children, respectively (age 14.1 ± 2.5 years and 14.2 ± 3.9 years), of whom 16% and 36% had MH (defined as SESCD<3).

RESULTS

In multivariable models, the stooling item of the PCDAI, erythrocyte sedimentation rate, and level of fecal calprotectin were associated with SESCD (all P < .05). We added data on level of C-reactive protein to develop the MINI index. MINI scores below 8 identified children with MH with 88% sensitivity and 85% specificity in the derivation cohort and with 84% sensitivity and 87% specificity in the validation cohorts. Ninety percent of the patients in the validation cohort with scores of 8 or more had active mucosal inflammation, yet 78% of patients with scores below 8 had MH. Scores below 6 increase the positive predictive value to 86%.

CONCLUSIONS

We developed an index to non-invasively assess mucosal inflammation in children with CD. This index, identifies children with MH with high sensitivity and specificity. The added benefit of MINI over measurement of fecal calprotectin was small but significant, especially for patients with concentrations of fecal calprotectin from 100 to 599 μg/g. ClinicalTrials.gov no: NCT01881490.

Korean Children and Adolescents with Crohn's Disease Are More Likely to Present with Perianal Fistulizing Disease at Diagnosis Compared to Their European Counterparts

PURPOSE

We aimed to investigate the disease phenotype of Korean pediatric Crohn's disease (CD) patients at diagnosis according to the Paris classification by comparison with patients from the European multicenter 5-years recruitment of children with newly developed IBD (EUROKIDS registry).

METHODS

Korean children and adolescents who had been newly diagnosed with CD at the age of <18 years during 2013-2016 were included in this multicenter retrospective study. Disease phenotype at diagnosis was classified according to the Paris classification, and compared with the published data from the EUROKIDS study.

RESULTS

A total of 255 patients were included. The median diagnosis age was 14.7 years (range, 0.8-17.9 years). No significant difference was observed in male-to-female ratio with EUROKIDS (1.9:1 vs. 1.45:1, p=0.062). The proportion of children aged <10 years was significantly lower in Koreans (7.1% vs. 19.6%, p<0.001). Colonic disease was less prominent (10.0% vs. 27.3%, p<0.001), while upper GI involvement was more prominent in Korean children (59.3% vs. 46.2%, p<0.001). The proportion with perianal fistulizing disease at diagnosis was significantly higher in Korean patients (44.8% vs. 8.2%, p<0.001). A separate analysis of Korean patients revealed that perianal fistulizing disease at diagnosis was positively associated with male sex and body mass index z-score (odds ratio [OR]=2.12, 95% confidence interval [CI]=1.20-3.76, p=0.010; and OR=1.29, 95% CI=1.05-1.58, p=0.015, respectively).

CONCLUSION

Approximately half of pediatric CD patients in Korea present with perianal fistulas and/or abscesses at diagnosis, which is a distinct feature of CD in Korean children and adolescents compared to their European counterparts. An underlying genetic difference between ethnicities may play a role in this expression of different phenotypes in pediatric CD.

Correlation of Dickkopf-1 with Inflammation in Crohn Disease

OBJECTIVE

To explore the potential roles of Dickkopf-1 (DKK-1) and b-catenin in Crohn disease, and to evaluate the effects of a tumor necrosis factor (TNF)-a inhibitor on Wnt signaling in patients with the disease.

METHODS

We enrolled 21 patients who received infliximab treatment for one year and achieved clinical remission during the treatment period. Disease activity was graded according to the Pediatric Crohn's Disease Activity Index (PCDAI). Peripheral blood and colonic mucosal specimens were collected from all patients with Crohn disease and from 14 healthy controls. DKK-1 levels in serum were detected by enzyme-linked immunosorbent assay (ELISA). Total RNA for DKK-1 and b-catenin from the frozen colonic tissue were obtained via real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Serum C-reactive protein (CRP) levels, erythrocyte sedimentation rates (ESR), and albumin were also measured in patients with Crohn disease before and after infliximab therapy.

RESULTS

The serum levels of DKK-1 were significantly higher in patients with Crohn disease than in healthy controls (P=0.003) and were decreased in those treated with infliximab (P=0.026). Serum DKK-1 level was correlated with levels of ESR (r=0.527, P=0.025), CRP (r=0.502, P=0.034), albumin (r=0.363, P=0.021) and PCDAI (r =0.462, P=0.054) in Crohn disease. DKK-1 mRNA expression in the colonic mucosa was higher in patients than in controls and decreased after infliximab treatment. b-catenin expression in the colonic mucosa was lower in patients than in controls and increased after infliximab treatment. However, the differences were not significant (P<0.05).

CONCLUSIONS

DKK-1 might be an important mediator of the pathogenesis of Crohn disease, and changes in DKK-1 levels may serve as biomarkers of inflammation in these patients.

P5279Pericardial inflammation basced on cardiac magnetic resonance imaging in patients with tuberculous pericarditis

Background

While constrictive pericarditis has been traditionally considered a disabling disease, reversible constrictive pericarditis has been described in previous studies. But there are limited studies on cardiac imaging of tuberculous pericarditis. In particular, no studies on cardiac magnetic resonance imaging (CMR) have been reported. We aimed to investigate CMR findings including pericardial late gadolinium enhancement (LGE) and T2 fat suppression and black blood sequences in patients with tuberculous pericarditis.

Methods

We retrospectively analyzed medical records of patients with tuberculous pericarditis between January 2010 and January 2017 in Samsung Medical Center. Definite diagnosis of tuberculous pericarditis is based on the identification of Mycobacterium tuberculosis in pericardial fluid or tissue; probable diagnosis was made when there was other evidence of tuberculosis elsewhere in patients with unexplained pericarditis. We performed CMR at initial diagnosis. Treatment consists of the standard 4-drug antituberculosis regimen for 6 months with or without steroids. Echocardiography was also conducted at initial diagnosis and 6 months later.

Results

Total 39 cases with tuberculous pericarditis in immunocompetent patients were enrolled. Ten patients were diagnosed as definite tuberculous pericarditis. CMR finding at initial diagnosis divided into five groups: 1) pericardial effusion only (n=20, 51.3%), 2) effusive constrictive pericarditis (n=5, 12.8%), 3) constrictive pericarditis (n=11, 28.2%), 4) pericardial abscess formation (n=4, 10.3%) and 5) absence of pericardial effusion and constrictive physiology (n=1, 2.6%). One of the 4 patients with pericardial abscess formation was together with pericardial effusion and the other was accompanied by effusive constrictive pericarditis. Pericardial thickness increased to more than 4mm in 25 patients (64.1%) and the mean pericardial thickness was 10.0±6.9mm. Delayed enhancement of pericardium was noticed in 29 patients (74.4%). In T2 fat suppression and black blood sequences, 30 patients showed increased T2 signal intensity indicating inflammation with extensive edema. Pericardial thickening (>4mm) with constriction (n=15) was not statistically significant in the delayed enhancement and increased T2 signal intensity compared with pericardial thickening without constrictive pericarditis (n=10) (delayed enhancement 93.8% vs. 77.8% p=0.287; increased T2 signal intensity 88.9% vs. 87.5%, p=0.713). After 6 months, only 3 patients still had constrictive pericarditis in echocardiography.

Effusive constrictive pericarditis

Conclusions

Pericardial thickening is associated with delayed enhancement and increased T2 signal intensity in patients with tuberculous pericarditis regardless of constrictive pericarditis. Even though there were hemodynamic feature of constrictive pericarditis and pericardial inflammation with extensive edema in CMR at initial diagnosis, 80% of the patients were improved from constrictive pericarditis.

Acknowledgement/Funding

None

Prognostic value of CT myocardial perfusion imaging and CT-derived fractional flow reserve for major adverse cardiac events in patients with coronary artery disease

OBJECTIVES

The purpose of this study was to analyze the prognostic value of dynamic CT perfusion imaging (CTP) and CT derived fractional flow reserve (CT-FFR) for major adverse cardiac events (MACE).

METHODS

81 patients from 4 institutions underwent coronary computed tomography angiography (CCTA) with dynamic CTP imaging and CT-FFR analysis. Patients were followed-up at 6, 12, and 18 months after imaging. MACE were defined as cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, or revascularization. CT-FFR was computed for each major coronary artery using an artificial intelligence-based application. CTP studies were analyzed per vessel territory using an index myocardial blood flow, the ratio between territory and global MBF. The prognostic value of CCTA, CT-FFR, and CTP was investigated with a univariate and multivariate Cox proportional hazards regression model.

RESULTS

243 vessels in 81 patients were interrogated by CCTA with CT-FFR and 243 vessel territories (1296 segments) were evaluated with dynamic CTP imaging. Of the 81 patients, 25 (31%) experienced MACE during follow-up. In univariate analysis, a positive index-MBF resulted in the largest risk for MACE (HR 11.4) compared to CCTA (HR 2.6) and CT-FFR (HR 4.6). In multivariate analysis, including clinical factors, CCTA, CT-FFR, and index-MBF, only index-MBF significantly contributed to the risk of MACE (HR 10.1), unlike CCTA (HR 1.2) and CT-FFR (HR 2.2).

CONCLUSION

Our study provides initial evidence that dynamic CTP alone has the highest prognostic value for MACE compared to CCTA and CT-FFR individually or a combination of the three, independent of clinical risk factors.

Infliximab Trough Levels Are Associated With Mucosal Healing During Maintenance Treatment With Infliximab in Paediatric Crohn's Disease

BACKGROUND AND AIMS

Mucosal healing is an important treatment goal in Crohn's disease. We investigated the association between serum infliximab trough levels and mucosal healing, and the infliximab cut-off levels required for mucosal healing in paediatric patients.

METHODS

In this multicentre, retrospective, cross-sectional study, medical records and electronic data of paediatric patients with luminal Crohn's disease, who had received infliximab for ≥1 year, were examined. Ileocolonoscopy was performed on the same day as the infliximab infusion, and serum samples for trough levels were collected immediately before infusion. Mucosal healing was defined as a Simple Endoscopic Score for Crohn's Disease of 0. Univariate, multivariate logistic regression, and receiver operating characteristic curve analyses were performed.

RESULTS

Overall, 105 patients [median age 14.8 years] were included, with mucosal healing observed in 48.6%. Median serum infliximab trough levels were higher in patients with mucosal healing [4.5 µg/mL] than without [3.3 µg/mL, p = 0.002]. In the final multivariate model, infliximab trough level ≥4.2 µg/mL [p = 0.002] and ≥1-year duration from diagnosis to infliximab treatment [p = 0.003] were positively and negatively associated with mucosal healing, respectively. The infliximab trough level for achieving mucosal healing with a specificity of 80% was ≥5 µg/mL.

CONCLUSIONS

Associations between serum infliximab trough concentrations and mucosal healing were observed in paediatric patients. Identification of the infliximab trough level that positively associates with mucosal healing in most paediatric patients with Crohn's disease [≥5 µg/mL] may guide treatment decisions to optimise therapeutic response in the era of treat-to-target.

The Characteristics and Outcomes of Abernethy Syndrome in Korean Children: A Single Center Study

PURPOSE

Abernethy malformation is a rare condition, which was first described in 1793 as a congenital extrahepatic porto-systemic shunt (CEPS) directing splanchnic blood flow into the inferior vena cava. Eighty cases have been published so far that reported CEPS, while in Korea, very few cases have been reported. Through this study, we present 6 cases of patients diagnosed with CEPS at Samsung Medical Center and compare these with other such cases published in France and China.

METHODS

We reviewed clinical, laboratory, and imaging data of 6 children with CEPS in our pediatric clinic between 2004 and 2017.

RESULTS

A total of 6 children with CEPS was included in this study, namely, one with type 1a, two with type 1b, and three with type 2 CEPS. The most common presenting symptom was gastrointestinal bleeding (50.0%). Therapeutic interventions included shunting vessel ligation (16.7%) in type 2 CEPS and liver transplantation (16.7%) in type 2 CEPS patient with suddenly developed hepatic encephalopathy.

CONCLUSION

There is no consensus guideline for the optimal management of patients with CEPS. Large-sample studies regarding CEPS are needed to evaluate the characteristics of patients with CEPS and determine the treatment guideline for CEPS.

Diagnostic Performance of Multidetector Computerized Tomography in the Detection of Abdominal Complications Early and Late After Liver Transplantation: A 10-Year Experience

BACKGROUND

Multidetector computerized tomography (MDCT) is considered to be a fast noninvasive diagnostic technique for the evaluation of postoperative complications in patients with liver transplantation (LT). However, its role has not been fully established in the diagnosis for detecting complications after liver transplantation. The aim of this work was to evaluate the diagnostic performance of MDCT for detecting abdominal complications in the early and late periods after LT.

METHODS

We retrospectively enrolled 75 patients who had undergone LT from March 2006 to January 2010, followed by MDCT from March 2006 to November 2017. Patients were divided into 2 groups according to the timing after LT: within the first 3 months (early period) or ≥3 months after LT (late period). We evaluated vascular, biliary, and other complications on MDCT. Angiography, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography were used as reference standards.

RESULTS

We initially found 77 complications in 45 patients (60.0%) with the use of MDCT. After comparison with the reference standards, 83 complications were diagnosed in 49 patients (65.3%). Forty-seven complications (34 vascular, 10 biliary, 3 other complications) were diagnosed in 33 patients (44.0%) during the early period, and 36 complications (6 vascular, 20 biliary, 10 other complications) were detected in 27 patients (36.0%) in the late period. The sensitivity, specificity, and diagnostic accuracy of MDCT for diagnosing overall complications were, respectively, 93.6%, 90.2%, and 92.0% in the early period (for vascular complications: 97.1%, 92.6%, and 94.3%,; for biliary complications: 80.0%, 100%, and 97.7%) and 77.8%, 98.1%, and 89.8% in the late period (for vascular complications: 83.3%, 100%, and 98.9%; for biliary complications: 65.0%, 98.6%, and 90.9%).

CONCLUSIONS

Although MDCT in the late period should be interpreted with caution in patients with suspected biliary complication, MDCT is a reliable diagnostic technique for the identification of early and late abdominal complications after LT.

A contact investigation after exposure to a child with disseminated tuberculosis mimicking inflammatory bowel disease

Purpose

Tuberculosis (TB) is one of the most important diseases that cause significant mortality and morbidity in young children. Data on TB transmission from an infected child are limited. Herein, we report a case of disseminated TB in a child and conducted a contact investigation among exposed individuals.

Methods

A 4-year-old child without Bacille Calmette-Guérin vaccination was diagnosed as having culture-proven disseminated TB. The child initially presented with symptoms of inflammatory bowel disease, and nosocomial and kindergarten exposures were reported. The exposed individuals to the index case were divided into 3 groups, namely household, nosocomial, or kindergarten contacts. Evaluation was performed following the Korean guidelines for TB. Kindergarten contacts were further divided into close or casual contacts. Chest radiography and tuberculin skin test or interferon-gamma-releasing assay were performed for the contacts.

Results

We examined 327 individuals (3 household, 10 nosocomial, and 314 kindergarten contacts), of whom 18 (5.5%), the brother of the index patient, and 17 kindergarten children were diagnosed as having latent TB infection (LTBI). LTBI diagnosis was more frequent in the children who had close kindergarten contact with the index case (17.1% vs. 4.4%, P=0.007). None of the cases had active TB.

Conclusion

This is the first reported case of TB transmission among young children from a pediatric patient with disseminated TB in Korea. TB should be emphasized as a possible cause of chronic diarrhea and failure to thrive in children. A national TB control policy has been actively applied to identify Korean children with LTBI.

Early Infliximab Yields Superior Long-Term Effects on Linear Growth in Pediatric Crohn's Disease Patients

Background/Aims

Information regarding the efficacy of early infliximab treatment in pediatric patients with Crohn’s disease (CD) is limited. We aimed to evaluate the impact of early combined immunosuppression on linear growth in pediatric patients with CD by performing step-up comparisons.

Methods

This retrospective study included pediatric patients with moderate-to-severe CD, who received a combination therapy with infliximab and azathioprine for at least 3 years and sustained corticosteroid-free remission without loss of response. The z-scores of the growth indicators obtained at the time of diagnosis and annually for 3 years thereafter were compared between the two groups.

Results

The early combined immunosuppression group displayed significantly increased linear growth 3 years after diagnosis (p=0.026). A significant difference was also observed in the linear growth 3 years after diagnosis between subgroups of Tanner stages 1–2 (p=0.016).

Conclusions

The early introduction of biologics should be considered to improve linear growth in pediatric patients with CD.

A Case of Glycogen Storage Disease IV with Rare Homozygous Mutations in the Glycogen Branching Enzyme Gene

Glycogen storage disease (GSD) IV is a rare autosomal recessive inherited disorder caused by mutations in the gene coding for glycogen branching enzyme leading to progressive liver disease. GSD IV is associated with mutations in GBE1, which encodes the glycogen branching enzyme. We report a case of GSD IV with rare homozygous mutations in the GBE1 gene (c.791G>A (p.Gly264Glu), which was successfully treated by liver transplantation.