Pulmonary function of healthy Korean children from three independent birth cohorts: Validation of the Global Lung Function Initiative 2012 equation

BACKGROUND AND OBJECTIVE

Global Lung Function Initiative (GLI) 2012 equations were developed to resolve the age-related disparity in interpreting spirometry results. Local validation of the equation is needed, especially in Northeast Asian children. This study evaluated the GLI equation in Korean children.

METHODS

Spirometry indices (FEV1, FVC, FEV1/FVC, and FEF25%-75%) and clinical information were gathered from three population-based birth cohorts. Predicted GLI reference values and z scores of spirometry results were calculated for 1239 healthy children. The mean, standard deviation of z scores were compared with the expected 0 and 1. Probabilities of falling below the lower limit of normal (LLN) (z score: -1.64) were compared with the expected value 5%. GLI z scores were assessed according to low (<-2), normal (≥-2 and ≤2), and high (>2) BMI z score groups.

RESULTS

Mean z scores significantly differed from 0 for FEV1/FVC in males (mean [95% confidence interval]: 0.18 [0.08, 0.27]) and forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) in females (-0.23 [-0.31, -0.15] and -0.26 [-0.36, -0.16], respectively). The standard deviation was larger than 1 for all variables in males and FVC and FEV1/FVC in females. The probability of falling below the LLN was significantly larger than 5% for FEV1 (12.13% [9.64, 14.77]), FVC (15.86% [13.06, 18.81]), and forced expiratory flow at 25%-75% of forced vital capacity (FEF25%-75%) (7.31% [5.29, 9.49]) in males and FVC (11.91% [9.40, 14.60]) in females. FEV1 and FVC z scores increased across low to high body mass index (BMI) groups, and FEV1/FVC decreased from low to high BMI groups.

CONCLUSION

GLI equations marginally differ from real-world values, which should be considered by pulmonologists in practice or research.

Is There an Association Between Psychiatric Disorders and Adolescent Idiopathic Scoliosis? A Large-database Study

BACKGROUND

Children with adolescent idiopathic scoliosis (AIS) have reduced quality of life related to poor self-image, perhaps because of cosmetic concerns. However, there has not been a large-database epidemiologic study on the association between psychiatric disorders and scoliosis.

QUESTIONS/PURPOSES

Using the Korean National Health Insurance database, we asked: (1) How common are psychiatric disorders among children with AIS? (2) After controlling for gender, age, insurance type, and residential district, are psychiatric disorders more common among children with AIS than among age-matched controls?

METHODS

A retrospective analysis was conducted using sample datasets from the Health Insurance Review and Assessment Service from 2012 to 2016, which is a 10% randomly extracted sample of total inpatients and outpatients each year. The mean number of total patients in each dataset was 1,047,603 ± 34,534. The mean number of children with AIS was 7409 ± 158 for each year. The age criteria was 10 to 19 years for the matching. Mood disorders, anxiety disorders, and behavioral disorders were selected as disorders possibly associated with AIS. We identified children with AIS who had any of the disorders above, and we obtained the prevalence of these disorders based on diagnostic codes. As an exploratory analysis, clinically meaningful variables were selected among the available codes in the dataset, and a univariable logistic regression test was performed for each variable. A multivariable logistic regression test with advanced variables was performed to identify the adjusted odds ratios of psychiatric disorders in children with AIS.

RESULTS

The median (range) prevalence of psychiatric disorders in children with AIS from 2012 to 2016 was 7% (6% to 7%). Compared with children who did not have AIS, and after controlling for gender, age, insurance type, and residential district, children with AIS were more likely to have psychiatric disorders in all 5 years. The adjusted ORs of psychiatric disorders in children with AIS compared with children who did not have AIS ranged from 1.47 to 1.74 (2012: OR 1.60 [95% CI 1.46 to 1.75]; p < 0.001; 2013: OR 1.73 [95% CI 1.58 to 1.89]; p < 0.001; 2014: OR 1.74 [95% CI 1.59 to 1.91]; p < 0.001; 2015: OR 1.71 [95% CI 1.56 to 1.88]; p < 0.001; 2016: OR 1.47 [95% CI 1.33 to 1.62]; p < 0.001).

CONCLUSION

Considering the higher prevalence of psychiatric disorders in children with AIS compared with children who did not have AIS, children with AIS and their parents should be counseled about the increased risk of deteriorating mental health of the patients, and surgeons should provide early referral to pediatric psychiatrists. Further studies should investigate the effect of the factors related to AIS, such as curve type, Cobb angle, and treatment modality.

LEVEL OF EVIDENCE

Level III, prognostic study.

Invasive dental procedures as risk factors for postoperative spinal infection and the effect of antibiotic prophylaxis

AIM

To identify invasive dental procedures as a risk factor for postoperative spinal infection (PSI) and evaluate the effectiveness of antibiotic prophylaxis.

MATERIALS AND METHODS

We analysed 229,335 patients who underwent spinal surgery with instrumentation from 2010 to 2017, using the nationwide database. The incidence of spinal infection 2 years after surgery was determined. Invasive dental procedures as a risk factor for PSI and the effects of antibiotic prophylaxis during this period were also analysed.

RESULTS

A total of 15,346 patients (6.69%) were diagnosed with PSI. It was found that advanced age, male sex, and a high Charlson Comorbidity Index were risk factors for PSI. The risk of PSI did not increase following dental procedures (adjusted hazard ratio [HR] 0.850; 95% confidence interval [CI], 0.793-0.912) and was not affected by antibiotics (adjusted HR 1.097; 95% CI, 0.987-1.218). Patients who received dental treatment as early as 3 months after spinal surgery had the lowest risk of postoperative infection (adjusted HR 0.869; 95% CI, 0.795-0.950).

CONCLUSIONS

Invasive dental procedure does not increase the risk of PSI, and antibiotic prophylaxis before dental procedure was not effective in preventing spinal infection.

Handgrip Strength Correlated with Falling Risk in Patients with Degenerative Cervical Myelopathy

Background: Few studies have investigated associations between hand grip strength (HGS) and the surgical outcomes of degenerative cervical myelopathy (DCM). Methods: This study was designed as a prospective observational study of 203 patients who had undergone fusion surgery for DCM. We divided the patients according to sex and HGS differences. Clinical outcome parameters, including HGS, a fall diary and four functional mobility tests (alternative step test, six-meter walk test, timed up and go test, and sit-to-stand test) were measured preoperatively, at 3 months and 1 year after surgery. Results: Mean patient ages were 59.93 years in the male group and 67.33 years in the female group (p = 0.000; independent t-test). The mean HGS of both hands improved significantly at postoperative 3 months and 1 year in all patients (p = 0.000 for both; ANOVA). In male patients, preoperative risk of falls was negatively correlated with HGS (p = 0.000). In female patients, pre- and postoperative risk of falls were correlated negatively with HGS (p = 0.000). The postoperative incidence of falls decreased in both groups (p = 0.000) Conclusions: Postoperative HGS in patients with DCM is correlated with postoperative falls and functional outcome differently, when comparing male and female patients, for predicting favorable outcomes and neurologic deficit recovery after surgery in DCM patients.

Incidence rate of congenital scoliosis estimated from a nationwide health insurance database

To investigate the epidemiology of congenital scoliosis (CS) and treatment trends. An age-matched, nationwide, population-based study was conducted using the National Health Insurance and Health Insurance Review and Assessment databases from 2010 to 2015. Data regarding the diagnosis and treatment of scoliosis were extracted using International Classifications of Diseases, 10th revision codes. The age-matched normal population was determined from the Korean Statistical Information Service database. We analyzed the incidence rate of CS according to age and sex, as well as the proportion of surgically treated patients. A total of 1664 patients (aged 0-19 years) were diagnosed with CS. The overall average incidence rate of CS over the 5-year period was 3.08 per 100,000 persons, with the highest and second highest rates at 0 years and 12-16 years of age, respectively. The incidence rate stratified by age ranged from 1.5 to 20.1 per 100,000 persons among the age-matched normal population, with peaks at 0 years of age and the second growth spurt in adolescence (12-16 years for males; 10-14 years for females). Anterior surgery was rarely performed; posterior surgery was performed in 92 patients (5.5% of all patients), with the highest prevalence (56.5%) in patients diagnosed at 10-14 years of age. The overall average incidence rate of CS over a 5-year period was 3.08 per 100,000 persons. Only 5.5% of patients underwent surgery within 5 years after the initial diagnosis.

Hand grip strength can predict clinical outcomes and risk of falls after decompression and instrumented posterolateral fusion for lumbar spinal stenosis

BACKGROUND CONTEXT

There has been limited research on the association between hand grip strength (HGS) as one of the diagnostic criteria for sarcopenia and surgical outcomes of lumbar spinal stenosis (LSS).

PURPOSE

We aimed to determine the effect of HGS on surgical outcomes and risk of fall in patients with LSS.

STUDY DESIGN

This is a retrospective observational study.

PATIENT SAMPLE

We included 200 patients who underwent spinal surgery for LSS.

OUTCOME MEASURES

We recorded clinical outcome parameters, including Oswestry Disability Index (ODI), Euro-QOL (EQ-5D), and visual analog scale (VAS) scores for back or leg pain. To assess the risk of fall we used HGS and four functional mobility tests (alternative step test, six-meter walk test, timed up and go test, sit-to-stand test).

MATERIALS AND METHODS

ODI, EQ-5D, and VAS scores for back and leg pain were assessed preoperatively and 1 year after surgery. The four functional mobility tests were assessed at each time point during the 1-year follow-up period to assess the risk of fall in patients with LSS. We divided the patient cohort according to sex and allocated them into two different groups based on HGS: high HGS (≥26 kg for men, n=26; ≥18 kg for women, n=35), and low HGS (<26 kg for men, n=48; <18 kg for women, n=91). The pre- and postoperative ODI, EQ-5D, and VAS scores for back and leg pain, as well as the functional mobility test results, and demographic data were compared between the two groups using independent t tests. Correlations between HGS and clinical outcome parameters were analyzed using Pearson correlation.

RESULTS

In women and men, HGS correlated with the preoperative/postoperative ODI (r₁=-0.217/r₂=-0.345 in women, and r₁=-0.384/r₂=-0.411 in men) and EQ-5D scores (r₁=0.190/r₂=0.309 in women, and r₁=0.373/r₂=0.467 in men). HGS also correlated with the four postoperative results for the functional mobility tests: alternative step test (r=-0.238 in women, r=-0.431 in men), six-meter walk test (r=-0.232 in women, r=-0.282 in men), timed up and go test (r=-0.285 in women, r=-0.359 in men), and sit-to-stand test (r=-0.238 in women, r=-0.251 in men). The preoperative and postoperative ODI and EQ-5D scores in the high HGS group were superior to those in the low HGS group. Among the four functional mobility tests, preoperative and postoperative six-meter walk test results showed improvements in the high HGS group.

CONCLUSIONS

Considering the multifactorial nature of falls, HGS may be a useful surrogate marker for predicting the risk of falls and clinical outcomes in patients with LSS.

Predicting inadequate treatment response in children with chronic spontaneous urticaria

BACKGROUND

We aimed to investigate the treatment response and associated factors for loss of control in children with chronic spontaneous urticaria (CSU).

METHODS

A total of 240 CSU patients (aged 0-17 years) were enrolled in a single-center study in Korea from May 2014 to May 2019. We retrospectively reviewed the medical records and compared the duration of treatment and step of medications using the urticaria control test (UCT, range 0-16 points). Serum total immunoglobulin levels, eosinophil count, allergic sensitization, autologous serum skin test, antinuclear antibody, thyroid function test, erythrocyte sedimentation rate, and C-reactive protein were measured. The patients were divided into well-controlled (sustained UCT ≥12), partly controlled (fluctuating UCT around 12), and poorly controlled (sustained UCT <12) groups.

RESULTS

Of the 240 children, 150 (62.5%) achieved well-controlled status; 74 (30.8%), partly controlled; and 16 (6.7%), poorly controlled. Longer duration (adjusted odds ratio: 1.09, 95% confidence interval: 1.05-1.13, P < .001) and higher treatment steps (5.61, 2.82-11.14, P < .001) for reaching the initial 12 points or more of UCT score, initial urticaria activity score (UAS) score (1.06, 1.03-1.09, P < .001), and food sensitization (1.88, 1.03-3.46, P = .041) were associated with inadequate treatment response. The mean duration to symptom free for 1 month without medication was 14.6 months in the well-controlled group and 22.1 months in the partly controlled group (P = .002).

CONCLUSION

Children with CSU have a good treatment response. Longer duration and higher treatment step until the initial disease control, higher initial UAS7 score, and food sensitization can predict inadequate treatment response.

Vegetable dietary pattern may protect mild and persistent allergic rhinitis phenotype depending on genetic risk in school children

BACKGROUND

The effect of diet on allergic rhinitis (AR), its severity in children, and whether it modifies AR depending on genetic susceptibility are unknown. We investigated the association between dietary patterns and AR in school children and the influence of diet on AR according to a genetic risk score (GRS).

METHODS

Totally, 435 7-year-old school children were recruited from the Panel Study on Korean Children. We used dietary patterns (vegetable, sugar, and meat) and dietary inflammatory index (DII) as dietary parameters. AR and its severity were defined by questionnaires about treatment in the previous 12 months and the Allergic Rhinitis and its Impact on Asthma (ARIA) guideline, respectively. A GRS was calculated using 6 single nucleotide polymorphisms for allergic diseases.

RESULTS

A vegetable diet containing a lot of anti-inflammatory nutrients and higher vitamin D level in blood were negatively correlated, while DII was positively correlated with triglyceride level and triglyceride/HDL cholesterol. Vegetable diet (aOR, 95% CI = 0.73, 0.58-0.94) and DII (1.13, 1.01-1.28) were associated with AR risk. In particular, a high-vegetable diet resulted in a lower risk of mild and persistent AR (aOR, 95% CI = 0.24, 0.10-0.56) while a high DII represented a higher risk (2.33, 1.06-5.10). The protective effect of vegetable diet on AR appeared only among children with a lower GRS (adjusted P = .018).

CONCLUSIONS

A vegetable dietary pattern characterized by high intake of anti-inflammatory nutrients and higher vitamin D level in blood might be associated with a lower risk of mild and persistent AR. This beneficial effect is modified by a genetic factor.

Hand grip strength as a surrogate marker for postoperative changes in spinopelvic alignment in patients with lumbar spinal stenosis

There are a few studies on the postoperative changes in sagittal alignment and corresponding factors, including hand grip strength (HGS) and muscle performance tests for lumbar spinal stenosis (LSS). Thus, we aimed to determine whether HGS can be a surrogate marker for global sagittal alignment changes after decompression with fusion surgery for LSS. This retrospective observational study included 91 patients who underwent spine fusion surgery for LSS. Radiological spinopelvic parameters, including sagittal vertical axis (SVA), lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), global tilt (GT), and T1 pelvic angle (T1PA), were analyzed preoperatively and 1 year after posterior decompression and fusion surgery. To assess muscle performance, the 6-m walk (SMT), timed up and go (TUGT), and sit-to-stand (STS) tests were conducted. The relationship between HGS and postoperative SVA was examined through multiple linear regression analysis. Additionally, the relationship between HGS and preoperative/postoperative radiologic spinopelvic parameters and muscle performance test results was analyzed through Pearson's correlation. HGS was significantly correlated with age, preoperative and postoperative SVA, and the muscle performance tests. Furthermore, HGS was a factor that can significantly influence postoperative SVA changes in multiple linear regression analyses. Therefore, HGS may be a good predictor of postoperative SVA change.

Intraoperative real-time stress in degenerative lumbar spine surgery: simultaneous analysis of electroencephalography signals and heart rate variability: a pilot study

BACKGROUND CONTEXT

Interest in intraoperative stress has increased due to its potentially detrimental impact on surgical performance and burnout among spine surgeons.

PURPOSE

The purpose of this study was to analyze intraoperative stress in real time in terms of electroencephalography signals and heart rate variability using a wearable device during spine surgery.

STUDY DESIGN

Prospective observational study.

PATIENT SAMPLE

Five orthopedic spine surgeons with experience ranging from 1 to 30 years were included.

OUTCOME MEASURES

The outcome measures included stress levels among the spine surgeons and differences in stress parameters between novice and expert surgeons and between assistants and operators.

METHODS

From June 2018 to November 2018, 179 consecutive records of intraoperative stress measures, including intraoperative electroencephalography signals and heart rate variability, comprising beats per minute (BPM) and low frequency/high frequency ratio, for the orthopedic spine surgeons were prospectively gathered, compared, and analyzed.

RESULTS

Among all measures, sensory-motor rhythm (SMR) waves, gamma waves, and BPM differed significantly during surgery (analysis of variance; p=.040, .013, .002, respectively). Surgery duration and intraoperative bleeding were positively correlated with stress parameters, including gamma waves and tension. For operators, surgeon experience was negatively correlated with concentration, tension, and SMR, gamma, M-beta, and H-beta waves (Pearson correlation, p<.05). However, for assistants, surgeon experience was positively correlated with concentration, tension, BPM, and SMR, M-beta, H-beta, and gamma waves. Bleeding amounts were correlated positively with gamma waves and tension for both operators and assistants (Pearson correlation, p<.05). Stress among operators was higher than that among assistants in terms of low frequency/high frequency ratio.

CONCLUSIONS

Operators and surgeons with low experience exhibited higher stress levels during surgery, which should be addressed when scheduling elective surgery to ensure optimal conditions among spine surgeons.

Emphysematous osteomyelitis of the spine: A rare case report

RATIONALE

Emphysematous osteomyelitis is a rare disease caused by gas-forming bacteria. But only 45 cases have been reported in the literature since then.

PATIENT CONCERNS

A 72-year-old female presented to our hospital with severe lower back pain that aggravated 4 days ago.

DIAGNOSES

Computed tomography (CT) revealed intraosseous mottled air in the T12 and L1 vertebral bodies and epidural space. The enhanced T1 and T2 magnetic resonance imaging scans showed heterogeneous signal intensity of vertebral bodies, suggestive of emphysematous osteomyelitis.

INTERVENTIONS

Surgery was performed to identify culture strains and to remove emphysematous lesions of the vertebral body using extensive transpedicular irrigation.

OUTCOMES

Escherichia coli (E coli) was identified in the surgical specimen, and intravenous antibiotic therapy was continued with cefotaxime. The patient had a significant decrease in lower back pain after the surgery and the final CT scan before discharge revealed significantly decreased air at T12 and L1 vertebral bodies and no air density in the epidural space.

LESSONS

We present a patient diagnosed with emphysematous osteomyelitis in vertebral bodies caused by E coli and successfully treated with surgical intervention.

Biomechanical comparison of the angle of inserted screws and the length of anterior cervical plate systems with allograft spacers

BACKGROUND

Comparative studies of the biomechanical effects of plates of varying lengths and different screw insertion angles on allograft spacers are lacking.

METHODS

Finite element model analysis of a previously validated, three-dimensional, intact cervical spinal segment model of C3-6 was conducted in the present study. On the C5-6 segment, anterior discectomy and fusion were performed using allograft spacers and different combinations of anterior plates and screws. The biomechanical characteristics of combinations of short, medium, and maximal length plates with screw insertion angles of 0°, 8°, 16°, and 32° were analyzed.

FINDINGS

In flexion and extension, the risk of allograft spacer subsidence decreased as screw angles increased. Short plates with a screw insertion angle of 32° posed the lowest subsidence risk, similar to medium length plates with a screw insertion angle of 16°, in all motion conditions. The risk of bone yielding increased as plate length increased, but decreased as the screw insertion angle increased.

INTERPRETATION

Short plates with a large screw insertion angle (32°) showed the highest mechanical stability and load sharing of allograft spacers and the lowest risk of screw loosening. Accordingly, we recommend the use of a short plate and large screw insertion angle for anterior cervical discectomy and fusion.

Risk Factors of Clostridium Difficile Infection After Spinal Surgery: National Health Insurance Database

The purpose of this study was to evaluate risk factors of Clostridium Difficile infection (CDI) after spinal surgery using the Health Insurance Review and Assessment Service (HIRA) data. The incidence of postoperative CDI was investigated using HIRA data from 2012 to 2016. Cases involving CDI that occurred within a 30-day postoperative period were identified. Risk factors, including age, sex, comorbidities, postoperative infection, spinal surgery procedure, type of antibiotic, and duration of antibiotic use, were evaluated. Duration of hospital stay, medical cost, and mortality were also evaluated. In total, 71,322 patients were included. Presumed cases of CDI were identified in 57 patients, with CDI rate of 0.54 per 10,000 patient days. Advanced age, staged operation, postoperative infection, and the use of multiple antibiotics were significant risk factors. First-generation cephalosporins were shown to be associated with a lower incidence of CDI. CDI was also associated with longer hospital stays and increased medical cost, and it was an independent risk factor for increased mortality. Extra attention should be paid to patients at high risk for the development of postoperative CDI, and unnecessary use of multiple antibiotics should be avoided. Level of Evidence: Level III, retrospective cohort study.

Asthma predictive index as a useful diagnostic tool in preschool children: a cross-sectional study in Korea

BACKGROUND

It is challenging to diagnose asthma in preschool children. The asthma predictive index (API) has been used to predict asthma and decide whether to initiate treatment in preschool children.

PURPOSE

This study aimed to investigate the association between questionnaire-based current asthma with API, pulmonary function, airway hyperreactivity (AHR), fractional expiratory nitric oxide (FeNO), and atopic sensitization in preschool children.

METHODS

We performed a population-based cross-sectional study in 916 preschool children aged 4-6 years. We defined current asthma as the presence of both physician-diagnosed asthma and at least one wheezing episode within the previous 12 months using a modified International Study of Asthma and Allergies in Childhood questionnaire. Clinical and laboratory parameters were compared between groups according to the presence of current asthma.

RESULTS

The prevalence of current asthma was 3.9% in the study population. Children with current asthma showed a higher rate of positive bronchodilator response and loose and stringent API scores than children without current asthma. The stringent API was associated with current asthma with 72.2% sensitivity and 82.0% specificity. The diagnostic accuracy of the stringent API for current asthma was 0.771. However, no intergroup differences in spirometry results, methacholine provocation test results, FeNO level, or atopic sensitization rate were observed.

CONCLUSION

The questionnaire-based diagnosis of current asthma is associated with API, but not with spirometry, AHR, FeNO, or atopic sensitization in preschool children.

Biomechanical comparison of cervical discectomy/fusion model using allograft spacers between anterior and posterior fixation methods (lateral mass and pedicle screw)

BACKGROUND

The purpose of this study is to investigate effects of different fixation methods on the physical stress on allospacers, endplate-vertebral body, and implants using finite element model analyses.

METHODS

Stress distribution and subsidence risk according to the fixation methods under the condition of hybrid motion control were analyzed. The detailed finite element model of a previously validated, three-dimensional, intact cervical spinal segment model, with C5-C6 segmental fusion using allospacer, was used to evaluate the biomechanical characteristics of different fixation combinations, such as anterior plate/screws, lateral mass screw, and posterior pedicle screw.

FINDINGS

The load sharing on allospacers increased in extension in order of posterior pedicle screws (21.4%), lateral mass screws (31.5%), and anterior plate/screws (56.6%). lateral mass screw demonstrated the highest load sharing (68.1%) on the allospacer in flexion. The Peak von Mises stress of the allospacer was the lowest in flexion and axial rotation but the highest in extension with anterior plate/screws. Allospacer subsidence risk was the lowest in extension, lateral bending, and axial rotation with posterior pedicle screws but the lowest in flexion with anterior plate/screws. The bone-screw loosening risk was the lowest in all modes with posterior pedicle screws but the highest with anterior plate/screws.

INTERPRETATION

Posterior pedicle screws demonstrated the best mechanical stability of allospacer failure-subsidence and the lowest risk of screw loosening. Different motion restrictions depending on the fixation method should be considered for implant and allospacer safety.

High-flow nasal cannula oxygen therapy in children: a clinical review

High-flow nasal cannula (HFNC) is a relatively safe and effective noninvasive ventilation method that was recently accepted as a treatment option for acute respiratory support before endotracheal intubation or invasive ventilation. The action mechanism of HFNC includes a decrease in nasopharyngeal resistance, washout of dead space, reduction in inflow of ambient air, and an increase in airway pressure. In preterm infants, HFNC can be used to prevent reintubation and initial noninvasive respiratory support after birth. In children, flow level adjustments are crucial considering their maximal efficacy and complications. Randomized controlled studies suggest that HFNC can be used in cases of moderate to severe bronchiolitis upon initial low-flow oxygen failure. HFNC can also reduce intubation and mechanical ventilation in children with respiratory failure. Several observational studies have shown that HFNC can be beneficial in acute asthma and other respiratory distress. Multicenter randomized studies are warranted to determine the feasibility and adherence of HFNC and continuous positive airway pressure in pediatric intensive care units. The development of clinical guidelines for HFNC, including flow settings, indications, and contraindications, device management, efficacy identification, and safety issues are needed, particularly in children.

Management of isolated recurrence after surgery for pancreatic adenocarcinoma

BACKGROUND

Recurrence of pancreatic cancer after primary pancreatectomy occurs in the vast majority of patients. The role of surgical treatment for recurrent pancreatic cancer is not well established.

METHODS

Patients who underwent primary pancreatectomy with curative intent from 2000 to 2014 at a single large-volume centre were evaluated retrospectively. CT or PET was used to select patients with an isolated recurrence. The clinicopathological features and survival outcomes were compared according to treatment modalities.

RESULTS

Of the 1610 patients with pancreatic cancer who underwent resection, 1346 (83·6 per cent) were diagnosed with recurrent pancreatic cancer. Recurrence was locoregional in 366 patients (27·2 per cent), distant multifocal in 251 (18·6 per cent), distant isolated in 188 (14·0 per cent), locoregional plus distant in 153 (11·4 per cent) and peritoneal seeding in 388 (28·8 per cent). Of the 1346 patients with recurrence, 197 (14·6 per cent) had isolated recurrence; of these, 48 (24·4 per cent of all isolated recurrences; 3·6 per cent of all recurrences) underwent resection. Median survival of the 197 patients after diagnosis of isolated recurrence was 14·7 months; it was longer in patients who underwent surgical resection than among those treated non-surgically (23·5 versus 12·0 months; P = 0·014). Multivariable analysis showed that chemotherapy and resection for recurrence were associated with better prognosis. Median survival after recurrence was longest in the 23 patients with isolated pulmonary recurrence (33·3 months). Survival after recurrence was better in patients who underwent resection of isolated recurrence in the remnant pancreas (median 28·0 versus 12·0 months, P = 0·010) and lung (median 36·5 versus 9·5 months; P = 0·010) than in those who did not undergo resection.

CONCLUSION

Surgical resection may be considered an option for treatment of patients with isolated recurrent pancreatic cancer.

Clinical Features of Pingueculitis Revealed by Anterior Segment Optical Coherence Tomography Findings

PURPOSE

To investigate clinical features and treatment outcomes of pingueculitis with morphological assessments using anterior segment optical coherence tomography (AS-OCT).

METHODS

In this retrospective observational study, we examined 22 eyes of 22 patients with pingueculitis. All patients were treated with the same 2-week course of prednisolone acetate 1% drops four times per day. The clinical parameters evaluated were surface dimensions determined by slitlamp biomicroscopy, cross-sectional dimensions determined by AS-OCT, and symptom scores determined by patient surveys. Pretreatment and 1-month posttreatment values were compared with Wilcoxon signed-rank tests. Patients were followed up to 1 year after treatment.

RESULTS

Twenty-two eyes from 22 patients (4 men and 18 women) with an average age of 37.7±8.8 (range, 27-57) years and an average duration of symptoms of 22 (range, 5-60) days were included. The average follow-up period was 14.7±0.8 (range, 12-22) months. Mean pretreatment horizontal length, vertical length, conjunctival thickness, and cross-sectional area were 2.4±0.69 mm, 2.0±0.6 mm, 1.82±0.60 μm, and 5.14±2.05 mm, respectively. Mean posttreatment horizontal length, vertical length, conjunctival thickness, and area were 1.93±0.5 mm, 1.52±0.6 mm, 1.03±0.46 μm, and 2.33±0.83 mm, respectively. Mean pretreatment and posttreatment dry eye symptom scores were 3.27±0.77 and 1.13±0.38, respectively. The median pretreatment and posttreatment changes were statistically significant by Wilcoxon signed-rank tests for horizontal length (P<0.001), vertical length (P<0.001), conjunctival thickness (P=0.003), cross-sectional area (P=0.003), and dry eye symptom scores (P<0.001).

CONCLUSION

Anterior segment optical coherence tomography allows the quantification of differences in the pingueculitis measurements before and after treatment. In this retrospective study, a short course of topical steroids effectively treated the inflammation in a sustained manner. Anterior segment optical coherence tomography demonstrated significant reduction in the thickness and cross-sectional area of the pinguecula and a conversion back to a homogeneous conjunctival stroma.

Association between sensitization and allergic diseases in 7-years-old Korean children

BACKGROUND

Sensitization is associated with the exacerbation, severity, and prognosis of allergic diseases in children OBJECTIVE: We characterized the association between sensitization patterns and allergic diseases.

METHODS

A cohort of 548 children was enrolled from Panel Study of Korean Children (PSKC) study. Skin prick tests (SPTs) for 18 common allergens, blood tests, and methacholine bronchial challenge tests were performed at age 7. The Korean version of International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was used.

RESULTS

The sensitization rate on SPTs was 46.4%. Sensitization to indoor allergens showed an association with symptoms of asthma (adjusted odds ratio [aOR], 2.39; 95% confidence intervals [95% CIs], 1.10-5.23), allergic rhinitis (AR, aOR 2.08, 95% CIs 1.42-3.06), and atopic dermatitis (AD, aOR 2.36, 95% CIs 1.24-4.50) in the preceding 12 months. In contrast, sensitization to outdoor allergens was associated with AR diagnosis only (aOR 2.40, 95% CIs 1.30-4.41). The number of sensitized allergens was associated with a lifetime diagnosis and symptoms in the preceding 12 months of AR and asthma, but not with AD or BHR. A higher degree of sensitization to indoor allergens was associated with symptoms in the preceding 12 months of asthma, AR, AD, and that for outdoor allergens was associated with symptoms in the prior 12 months of asthma and AR.

CONCLUSION

The sensitization patterns including allergen type, number, and degree of sensitization are helpful for interpreting the association between sensitization and allergic diseases and identifying the pathophysiologies and diverse phenotypes of allergic diseases.

Profiles and characteristics of bronchial responsiveness in general 7-year-old children

BACKGROUND

Although bronchial responsiveness (BR) is usually categorized as normal or hyperresponsive to aid the diagnosis of asthma, it exists on a continuous spectrum, not in a dichotomous manner. We aimed to evaluate the distribution profile of BR in a general population of 7-year-olds.

METHODS

In 2015, 7-year-old Korean children from a nationwide birth cohort study visited regional study hospitals for skin prick test, standard spirometry, and bronchial provocation to establish reference values for the general population. Their BR degrees were categorized into five ordered groups: hyperresponsive BRs were classified into group 1 (provocative concentration (PC) of methacholine causing a 20% fall in forced expiratory volume in 1 second [FEV1], PC20 of <4 mg/mL) and group 2 (PC20 of ≥4 mg/mL and <16 mg/mL), and nonresponsive BRs were categorized into group 3 (final FEV1 percentage fall after inhaling 16 mg/mL of methacholine [FEV1%fall] of >15% and ≤20%), group 4 (FEV1%fall of >10% and ≤15%), and group 5 (FEV1%fall of ≤10%).

RESULTS

In total, 559 subjects finished all tests reliably. Groups 1 and 2 comprised 10.0% and 15.7% of the total population, respectively. Groups 3, 4, and 5 comprised 14.7%, 18.4%, and 41.1%, respectively. As the group number increased, the proportion of those with recent wheezing and those with indoor allergen sensitization decreased (P for trend = 0.001 and P for trend < 0.001, respectively), and the baseline FEV1/FVC increased (P for trend < 0.001) CONCLUSION: BR of the 7-year-olds in the general population, while showing a wide distribution across phenotypes, is associated with allergic symptoms, negatively correlated with baseline lung function and positively correlated with indoor allergen sensitization.

Asthma control test reflects not only lung function but also airway inflammation in children with stable asthma

Objective: Various numerical asthma control tools have been developed to distinguish different levels of symptom control. We aimed to examine whether the asthma control test (ACT) is reflective of objective findings such as lung function, fractional exhaled nitric oxide (FeNO) and laboratory data in patients with stable asthma.Methods: We included patients who were enrolled in the Korean Childhood Asthma Study. ACT, spirometry, blood tests and FeNO were performed in patients after stabilization of their asthma. We examined differences among spirometry parameters, blood tests and FeNO according to control status as determined by ACT and investigated for any significant correlations.Results: The study population consisted of 441 subjects. Spirometry showed that forced expiratory volume in one second (FEV₁), forced expiratory flow between 25% and 75% of forced vital capacity and FEV₁/forced vital capacity were all significantly higher in the controlled asthma group. Likewise, FeNO and percent-change in FEV₁ were both significantly lower in the controlled asthma group. In blood tests, the eosinophil fraction was significantly lower in the controlled asthma group while white blood cell count was significantly higher in the controlled asthma group. Lastly, among the various factors analyzed, only provocative concentration of methacholine causing a 20% fall in FEV₁ significantly correlated with ACT score.Conclusion: ACT is useful as part of the routine evaluation of asthmatic children and should be used as a complement to existing tools such as spirometry and FeNO measurement.