The Efficacy of Noninvasive Ventilation in Patients Affected by Rett Syndrome With Hypoventilation.

BACKGROUND: Rett syndrome is a progressive neurological disorder associated to several comorbidities that contribute significantly to impair lung function. Respiratory morbidity represents a major cause of death in this population. Little is known about the benefit of noninvasive ventilation. METHODS: We retrospectively enrolled patients with Rett syndrome who underwent a pneumological evaluation combined with a cardiorespiratory polygraphy and/or a pulse oximetry and capnography from 2012 to 2022. RESULTS: Medical records of 11 patients with Rett syndrome, mean age 13 ± 6 years, were evaluated. Most patients presented with both epilepsy and scoliosis. Five patients showed a pathologic sleep study and/or impaired night gas exchange: mean obstructive apnea-hypopnea index was 4 ± 3 events/hour; mean and minimal SpO2 were, respectively, 93% ± 2% and 83% ± 6%, while mean and maximal transcutaneous carbon dioxide monitoring (PtcCO2) were, respectively, 51 ± 5 mm Hg and 55 ± 8 mm Hg; and mean oxygen desaturation index was 13 ± 11 events/hour. These patients started noninvasive ventilation with clinical benefit and improved gas exchange mostly in terms of PtcCO2 (mean PtcCO2 51 ± 5 mm Hg before and 46 ± 6 mm Hg after noninvasive ventilation). CONCLUSIONS: Noninvasive ventilation is a suitable option for patients with Rett syndrome.

Sleep architecture and Nusinersen therapy in children with Spinal Muscular Atrophy type 1.

BACKGROUND: Spinal muscular atrophy (SMA) is a severe neuromuscular disorder, the phenotype of the disease is caused by the mutation of the SMN1 (survival motor neuron 1) gene which encodes for the SMN protein. Innovative treatments for SMA have become available and the first molecule approved is Nusinersen, an antisense oligonucleotide that increases the production of SMN protein. Nusinersen has been shown to be associated with a significant motor improvement and an increase of the event-free survival. For these reasons the aim of the present study is to assess if Nusinersen is able modify sleep architecture and microstructure and to improve sleep structure in these patients. METHODS: Sixteen patients affected by SMA1 were enrolled in the study (4 boys, 12 girls; median age 72.5 months, intelligence quotient range 24-84). All patients underwent complete nocturnal PSG before the start of the treatment trough intrathecal injections with Nusinersen (T0) and after the fifth infusion (day 180, T180). PSG recordings were visually scored and interpreted according to the indications of the American Academy of Sleep Medicine (AASM) and and microstructure by means of the Cyclic Alternating Pattern (CAP). RESULTS: After 6 months therapy we found a significantly reduced sleep latency and a significantly increased sleep efficiency. Regarding sleep microstructure parameters (CAP), we did not find any significant change after therapy however, it is worth mentioning that a moderate effect size was observed for the increase in CAP A3 index. CONCLUSIONS: We observed short-term effects of Nusinersen on sleep with an improvement in sleep efficiency and reduction in sleep onset latency; regarding sleep microstructure, a moderate effect size was found for the number of CAP A3 subtypes that slightly increased, possibly indicating a slightly higher arousability. This finding points at a probably overall better sleep pattern organization associated with the treatment, but they need to be confirmed by larger studies with patients treated earlier in life and for a longer period.

Telemedicine in children with medical complexity on home ventilation during the COVID-19 pandemic.

Children with medical complexity (CMC) are patients with one or more complex chronic conditions dependent on medical technologies. In our unit (Pediatric Pulmonology and Respiratory Intermediate Care Unit, Department of Pediatrics, "Bambino Gesù" Children's Hospital and Research Institute), we regularly follow-up CMC patients, particularly children on long-term, invasive (IMV) or noninvasive (NIV), ventilation. Children suffering from chronic diseases and with medical complexity have lost the possibility to go to the hospital during the COVID-19 pandemic. The aim of this article is to describe our experience with telemedicine (teleconsultation [TC] and telemonitoring of ventilator [TM]) in CMC on ventilation. We presented 21 children on long-term ventilation (NIV or IMV) whose planned hospital admission was postponed due to lockdown. A total of 12 healthcare problems were detected during scheduled TCs. Only one problem was not solved by our remote intervention. Specifically, TM has allowed us to change the ventilator parameters and to monitor patients on ventilation remotely. In conclusion, the use of telemedicine in CMC ventilated patients resulted in a feasible tool to avoid in-person visits during the pandemic.

Ventilators and Ventilatory Modalities.

Non-invasive ventilation is increasingly used in children for acute and chronic respiratory failure. Ventilators available for clinical use have different levels of complexity, and clinicians need to know in detail their characteristics, setting variables, and performances. A wide range of ventilators are currently used in non-invasive ventilation including bi-level ventilators, intermediate ventilators, and critical care ventilators. Simple or advanced continuous positive airway pressure devices are also available. Differences between ventilators may have implications on the development of asynchronies and air leaks and may be associated with discomfort and poor patient tolerance. Although pressure-targeted (controlled) mode is preferable in children because of barotrauma concerns, volume-targeted (controlled) ventilators are also available. Pressure support ventilation represents the most used non-invasive ventilation mode, as it is more physiological. The newest ventilators allow the clinicians to use the hybrid modes that combine the advantages of volume- and pressure-targeted (controlled) ventilation while limiting their drawbacks. The use of in-built software may help clinicians to optimize the ventilator setting as well as to objectively monitor patient adherence to the treatment. The present review aims to help the clinician with the choice of the ventilator and its ventilation modalities to ensure a successful non-invasive ventilation program.

Built-in software in children on long-term ventilation in real life practice.

Information gathered with built-in software (BIS) on new ventilators allow clinicians to access long-term noninvasive ventilation (LTNIV) data. Nevertheless, few evidence are available in literature that highlight potential strengths and disadvantages of using BIS in pediatrics. We aim to evaluate the use of BIS in a cohort of 90 children on LTNIV in our unit, focusing mainly on adherence, air leaks, and residual sleep events. We found that caregivers' perception of ventilator use is independent from objective adherence (P = .137). Furthermore, we failed to find any predictors of adherence. As regards air leaks, we found that pre-scholars' (0-6 years old) total air leaks are lower than teenagers' (more than 12 years old) (P < .05). Multiple regressive analysis showed that age at the beginning of therapy is a predictor of total air leaks: prescholars are associated with lower values (P < .05), while scholars (6-12 years old) are associated with higher values (P < .05). Finally, we explored the validity of BIS automatic scoring of sleep events (AHIBIS ) as compared with the manual scoring of polygraphy (AHIPG ). AHIBIS is within a range of 3.98 from AHIPG in 95% of cases, with a 64% of sensitivity and a 67% of specificity in identifying a pathological state. The disagreement between the two methods seems to increase for high AHI values. In conclusion, data gathered by BIS are a useful support tool for the clinician in assessing the course of LTNIV. However, clinicians must be aware of the several limitations of built-in software, especially in pediatrics.

Application of latent class analysis in assessing the awareness, attitude, practice and satisfaction of paediatricians on sleep disorder management in children in Italy.

AIM: To identify subgroups regarding paediatricians' awareness, attitude, practice and satisfaction about management of Sleep-Disordered Breathing (SDB) in Italy using Latent Class Analysis (LCA). METHODS: A cross-sectional study was conducted on a large sample of Italian paediatricians. Using a self-administered questionnaire, the study collected information on 420 Paediatric Hospital Paediatricians (PHPs) and 594 Family Care Paediatricians (FCPs). LCA was used to discover underlying response patterns, thus allowing identification of respondent groups with similar awareness, attitude, practice and satisfaction. A logistic regression model was used to investigate which independent variables influenced latent class membership. Analyses were performed using R 3.5.2 software. A p-value<0.05 was considered statistically significant. RESULTS: Two classes were identified: Class 1 (n = 368, 36.29%) "Untrained and poorly satisfied" and Class 2 (n = 646, 63.71%) "Trained and satisfied." Involving paediatric pneumologists or otorhinolaryngologists in clinical practice was associated with an increased probability of Class 2 membership (OR = 5.88, 95%CI [2.94-13.19]; OR = 15.95, 95% CI [10.92-23.81] respectively). Examining more than 20 children with SDB during the last month decreased the probability of Class 2 membership (OR = 0.29, 95% CI [0.14-0.61]). FCPs showed a higher probability of Class 2 membership than PHPs (OR = 4.64, 95% CI [3.31-6.55]). CONCLUSIONS: These findings suggest that the LCA approach can provide important information on how education and training could be tailored for different subgroups of paediatricians. In Italy standardized educational interventions improving paediatricians' screening of SDB are needed in order to guarantee efficient management of children with SDB and reduce the burden of disease.

Characteristics and outcomes in children on long-term mechanical ventilation: the experience of a pediatric tertiary center in Rome.

BACKGROUND: Children with chronic respiratory failure and/or sleep disordered breathing due to a broad range of diseases may require long-term ventilation to be managed at home. Advances in the use of long-term non-invasive ventilation has progressively leaded to a reduction of the need for invasive mechanical ventilation through tracheostomy. In this study, we sought to characterize a cohort of children using long-term NIV and IMV and to perform an analysis of those children who showed significant changes in ventilatory support management. METHODS: We performed a retrospective cohort study of pediatric (within 18 years old) patients using long-term, NIV and IMV, hospitalized in our center between January 1, 2000 and December 31, 2017. A total of 432 children were included in the study. Long Term Ventilation (LTV) was defined as IMV or NIV, performed on a daily basis, at least 6 h/day, for a period of at least 3 months. RESULTS: 315 (72.9%) received non-invasive ventilation (NIV); 117 (27.1%) received invasive mechanical ventilation (IMV). Children suffered mainly from neuromuscular (30.6%), upper airway (24.8%) and central nervous system diseases (22.7%). Children on IMV were significantly younger when they start LTV [NIV: 6.4 (1.2-12.8) years vs IMV 2.1 (0.8-7.8) years] (p < 0.001)]. IMV was likely associated with younger age at starting ventilatory support (aOR 0.9428; p = 0.0220), and being a child with home health care (aOR 11.4; p < 0.0001). Overtime 39 children improved (9%), 11 children on NIV (3.5%) received tracheostomy; 62 children died (14.3%); and 74 children (17.1%) were lost to follow-up (17.8% on NIV, 15.4% on IMV). CONCLUSIONS: Children on LTV suffered mainly from neuromuscular, upper airways, and central nervous system diseases. Children invasively ventilated usually started support younger and were more severely ills.

Decannulation in children affected by congenital central hypoventilation syndrome: A proposal of an algorithm from two European centers.

RATIONALE: Long-life ventilatory assistance is necessary for survival in pediatric patients with congenital central hypoventilation syndrome (CCHS). Invasive mechanical ventilation (IMV) through tracheostomy is the most used method, especially in the first years of life when the central nervous system is maturing. Nevertheless, IMV via tracheostomy is not ideal because tracheostomy in children is associated with impaired speech and language development, also frequent infections of the lower airway tract occur. OBJECTIVE: Only few reports describe the transition from IMV to the noninvasive method, ending with decannulation in CCHS affected patients. We aim to provide our experience regarding decannulation program in CCHS affected children and to describe a proposal of an algorithm concerning transition from invasive to noninvasive ventilation (NIV) in CCHS patients. METHODS: The study has been conducted retrospectively. Four children from two European centers underwent tracheostomy removal and decannulation, upon request of patients and their families. RESULTS: All children were trained to carry out tracheostomy capping before decannulation and underwent endoscopic assessment of upper and lower airway. Subsequently they started training to NIV at mean age of 106.25 months (±40.7 SD). Decannulation occurred 12 months after and no patients needed the reintroduction of tracheal cannula in either short or long term follow up. CONCLUSIONS: our study shows that effective liberation from IMV, the transition to NIV and decannulation are possible in CCHS affected children and offers a proposal of an algorithm which can be applied in selected centers.

Transition to adult care in young people with neuromuscular disease on non-invasive ventilation.

BACKGROUND: Long-term mechanical ventilation (LTV) with non-invasive ventilation (NIV) prolongs survival in patients with Neuromuscular Diseases (NMDs). Transition from paediatric to adult healthcare system is an undervalued and challenging issue for children with chronic conditions on mechanical ventilation. METHODS: this retrospective study aims to compare issues of young adults in age to transition to adult care (≥ 15 years old) affected by NMDs on NIV in two different Paediatric Respiratory Units in two different countries: Bambino Gesù Children's Hospital, Research Institute, (Rome, Italy) (BGCH) and the Paediatric Respiratory Unit of the Royal Brompton Hospital (London, UK) (RBHT). RESULTS: The median (min-max) age at starting ventilation was significantly different in the two groups (16 years old vs 12, p = 0.0006). We found significant difference in terms of median age at the time of observation (18 (15-22) vs 17 (15-19) years, p = 0.0294) and of type of referral (all the patients from the BGCH group were referred to paediatric services (n = 15, 100%), median age 18 (15-22); only 6 patients, in the RBHT group, with a median age 15.50 (15-17) years, were entirely referred to paediatric service). We found different sleep-disordered breathing assessments 6 full Polysomnographies, 7 Cardio-Respiratory Polygraphies and 2 oximetry with capnography (SpO2-tcCO2) studies in the BCGH group, while all patients of RBHT group were assessed with an SpO2-tcCO2 study. All patients from both groups underwent multidisciplinary assessment. CONCLUSIONS: In conclusion, patients with NMDs on NIV in age to transition to adult require complex multidisciplinary management: significant efforts are needed to achieve the proper transition to adult care.

Anti-Hypothalamus and Anti-Pituitary Auto-antibodies in ROHHAD Syndrome: Additional Evidence Supporting an Autoimmune Etiopathogenesis.

BACKGROUND: Rapid-onset Obesity with Hypothalamic dysfunction, Hypoventilation and Autonomic Dysregulation (ROHHAD) is a very rare and complex pediatric syndrome characterized by altered hypothalamic thermal regulation, pain threshold, and respiratory control, hyperphagia with rapid weight gain and, often, hypothalamic-pituitary dysfunction. Its etiopathogenesis remains undetermined. We investigated the presence of alterations to target genes and hypothalamic-pituitary autoimmunity in a patient with -ROHHAD syndrome. METHODS: A 3-year-old girl presenting with obesity after rapid weight gain was diagnosed with ROHHAD syndrome based on clinical features and abnormal biochemical and functional testing results. Because of worsening of rapid symptoms and demonstration of oligoclonal bands on cerebrospinal fluid (CSF) analysis, she was treated with plasmapheresis, methylprednisolone, anti-CD20 monoclonal antibodies, and azathioprine. Despite initial partial clinical improvement, the patient soon died of cardiorespiratory arrest. Post-mortem, whole exome sequencing, high-resolution comparative genomic hybridization array, and optimized indirect immunofluorescence (IIF) analysis were performed on blood and CSF. RESULTS: No putative causative genomic variants compatible with dominant or recessive inheritance nor clinically significant structural rearrangement were detected. IIF on serum and CSF demonstrated the presence of anti-pituitary and anti-hypothalamus autoantibodies. CONCLUSIONS: These findings support the involvement of autoimmunity in ROHHAD syndrome. However, response to immunosuppressive treatment was only transient and the patient died. Further cases are required to define the complex disease pathogenesis.

Effects of long-term non-invasive ventilation on sleep structure in children with Spinal Muscular Atrophy type 2.

OBJECTIVE: Changes of sleep architecture have been reported in children with Spinal Muscular Atrophy type 2 (SMA2), mainly represented by a decrease of arousability. No studies have evaluated the effect of long-term ventilation on sleep parameters in these children. The aim of this study was to evaluate the effects of long-term non-invasive positive pressure ventilation (LTNPPV) on sleep architecture and to assess the residual differences from normal controls. METHODS: Nine consecutive children with SMA2 underwent two distinct polysomnographic (PSG) studies, one in spontaneous breathing, and subsequently after LTNPPV. The results were then compared to 15 age-matched controls. RESULTS: SMA2 patients showed only slightly modified sleep architecture on LTNPPV: increased stage N2% and decreased number of awakenings, while several significant differences persisted between SMA2 patients on LTNPPV and controls (decreased total sleep time, number of awakenings, sleep efficiency, and percentage of REM sleep). Sleep microstructure, evaluated by means of the Cyclic alternating pattern (CAP) showed only marginal changes on LTNPPV (small shortening of CAP A1 subtype duration and small increase in CAP A3 index). Conversely, CAP parameters on LTNPPV showed significant differences between SMA2 patients vs. controls, with increased A1 subtype percentage and decreased percentage of A2 and A3 subtypes. CONCLUSIONS: This is the first study in children affected by SMA2 reporting data on sleep microstructure and their changes after LTNPPV. We found persisting, small but important changes in sleep microstructure during LTNPPV in these children, suggesting that this treatment only partially improves their arousability.

Dynamic expiratory CT: An effective non-invasive diagnostic exam for fragile children with suspected tracheo-bronchomalacia.

BACKGROUND: Tracheobronchomalacia, defined as variable collapse of the airways, has been recognized as an important cause of respiratory morbidity but still widely underdiagnosed. Bronchoscopy is still considered as the gold standard, but numerous limitations are known, especially for fragile sick children. Moreover, information on parenchymal lung disease cannot be described. There is a real need for a reliable, non-invasive test to help detection of airway and parenchymal malformations in children, specifically when bronchoscopy cannot be performed. METHODS AND RESULTS: 34 paediatric patients underwent cine multidector CT for ongoing respiratory symptoms and were included. All CT images were of good quality and sedation was never needed. Airway disease such as trachea-broncomalacia with/without stenosis was described in 53% with the first being more frequent. Bronchomalacia alone was described in 10 patients and in 4 patients was associated with tracheomalacia. Moreover, CT allowed identification of parenchymal disease in 10 patients. Airways stenosis alone was detected in seven patients. The majority of patients (85%) underwent also bronchoscopy for clinical decision. The agreement between CT and bronchoscopy was explored. The two examinations did not agree only in two cases. CT dynamic showed an excellent sensitivity of 100% (81.47-100 %), a great specificity of 82% (48.22-97.72 %), NPV 100%, and PPV 90% (72-96.9 %). CONCLUSION: Dynamic CT results an effective and highly sensitive diagnostic exam for children with tracheo-bronchomalacia. CT is especially indicated for those small and fragile patients that cannot undergo an invasive investigation. Moreover, CT allows a detailed evaluation both of the airways and the lungs which is useful for the clinical management.

Age and seasons influence on at-home pulse oximetry results in children evaluated for suspected obstructive sleep apnea.

BACKGROUND: Seasonal variability on obstructive sleep apnea has already been studied by polysomnography in children. Winter and spring season emerged as critical periods. No data are currently available for pulse oximetry performed at home. The aim of our study was to evaluate the effect of seasonality and age on the results of at-home pulse oximetry performed in children referred for suspected OSA. METHODS: We retrospectively studied 781 children (64.3% Males), aged 4.9 ± 2.5 years. For all patients, we evaluated both pulse oximetry metrics and the McGill Oximetry Score. Variables for seasonal groups were assessed using Kruskal-Wallis test. A logistic regression model was performed to assess the relationship between patients' main characteristics, season period and the likelihood to have an abnormal McGill Oximetry Score. RESULTS: Patients recorded during winter were significantly younger (p < 0.02), nadir SpO2 was significantly lower (p < 0.002) and DI4 significantly higher than during others seasons (p < 0.005). Moreover, patients recorded during winter were nearly 2 times more likely to have an abnormal MOS (aOR 1.949). The logistic regression showed that also younger age (p < 0.0001) was associated with a higher risk to find an abnormal pulse oximetry. CONCLUSIONS: In our study, the winter season confirms to be a critical period for pulse-oximetry and it should be taken into account by clinicians for a correct interpretation of tests. Our data show that also younger age affects the prevalence of abnormal at-home pulse oximetry in children.

Sleep in infants with congenital myasthenic syndromes.

BACKGROUND AND OBJECTIVES: Infants with congenital myasthenic syndrome (CMS) are at risk of brief resolved unexplained event (BRUE) and sleep-disordered breathing. The aim of the study was to explore sleep in infants with CMS with a particular focus on heart rate (HR) variability. METHODS: Overnight polygraphy was performed and HR variations associated with respiratory events were analysed. Bradycardia and tachycardia were defined as a variation of HR of ±10 bpm from baseline and analysed as events/hour. RESULTS: The data of 5 infants with CMS were analysed. Two patients had known mutations (COLQ and RAPSN). One patient had a tracheostomy. The apnoea-hypopnoea index (AHI) was abnormal in all the patients (range 2.8-47.7 events/h), with the highest AHI being observed in the 3 youngest infants. Nocturnal transcutaneous gas exchange was normal in all patients except the tracheostomised patient. Mean HR was 114 ± 23 bpm with a mean HR index of 4.5 ± 4.3 events/h. The amplitudes of HR variations (bradycardia or tachycardia) were around 15-20 bpm, regardless of the type of respiratory event, and comparable between patients. No correlations were found between HR indexes or variations and the type and mean duration of respiratory events. Ventilatory support was initiated in 3 infants immediately after the sleep study because of a high AHI and/or nocturnal hypoventilation. CONCLUSIONS: All 5 infants had an abnormal AHI with younger infants having the highest AHI. Three infants required ventilatory support after the polygraphy, underlining its clinical usefulness. No significant abnormalities of HR were observed during the sleep studies.

At-home pulse oximetry in children undergoing adenotonsillectomy for obstructive sleep apnea.

Nocturnal pulse oximetry has a high positive predictive value for polysomnographically diagnosed obstructive sleep apnoea (OSA) in children. When significant adenotonsillar hypertrophy is diagnosed, adenotonsillectomy (T&A) represents a common treatment for OSA in children. We investigated the role of pulse oximetry in predicting those patients, referred for suspected OSA, who subsequently needed T&A. At-home nocturnal pulse oximetry was performed on 380 children (65.7% males), median age 4.1(IRQ 3.0-5.6) years, referred for suspected OSA, and data were retrospectively analysed. For each recording McGill Oximetry Score (MOS) was categorized. Mean pulse rate (PR) z-score and pulse rate variability (PRV)-corrected (PRSD/meanPR) were significantly higher in children with abnormal MOS. Both parameters were significantly higher in subjects who underwent T&A compared with those not surgically treated. Both DI4 and PRV corrected showed a negative correlation with the elapsed time between pulse oximetry recordings and T&A. The logistic regression model showed a strong effect of an abnormal MOS as a predicting factor for T&A (adjusted odds ratio 19.7). CONCLUSIONS: In our study, children with OSA who subsequently needed T&A showed higher PRV compared to those without surgical indication. Children with abnormal MOS were nearly 20 times more likely to undergo T&A. What is Known: • Nocturnal pulse oximetry has a high positive predictive value for polysomnographically diagnosed obstructive sleep apnoea in children. • When significant adenotonsillar hypertrophy is diagnosed, adenotonsillectomy represents a common treatment for OSA in children. What is New: • An abnormal pulse oximetry highly predict the indication for adenotonsillectomy. • We suggest the use of at-home pulse oximetry as method to predict prescription of adenotonsillectomy, and this may be useful in contexts where polysomnography is not readily available.

Sleep architecture in children with spinal muscular atrophy type 2.

OBJECTIVE: There have been few published reports on the sleep patterns of patients with spinal muscular atrophy (SMA) type 2, and none on sleep microstructure. The aim of this study was to analyze sleep architecture and microstructure in a group of children with SMA type 2, compared with age-matched and sex-matched controls. METHODS: Seventeen SMA type 2 children (seven males, mean age 4.2 years) and 12 controls (five males, mean age 5.0 years) underwent full polysomnography to evaluate sleep architecture and microstructure by means of the Cyclic Alternating Pattern (CAP). RESULTS: Compared with the control children, the SMA type 2 patients showed a mild increase in the apnea/hypopnea index. Sleep was characterized by a decrease in the number of sleep stage shifts per hour, of percentage of stage N3, of stage R, and of sleep efficiency. On the contrary, significant increases of awakenings per hour, wake after sleep onset, and percentage of stage N1 were found. The CAP analysis revealed a significant increase in the percentage of A1 CAP subtypes, a reduction of that of A3 subtypes, and of A2 and A3 indexes. CONCLUSIONS: The results indicated an abnormality of sleep macrostructure and microstructure in SMA type 2 patients, which was characterized by a reduction of A2 and A3 subtypes (low and high power arousals), supporting the concept of a decreased arousability in SMA type 2 patients. Similar to a previous report on SMA type 1, the findings might be additional proof of central nervous system involvement, although these alterations are less severe than those observed in infants with SMA type 1.

Sleep architecture in infants with spinal muscular atrophy type 1.

OBJECTIVE: Few reports on sleep patterns of patients with spinal muscular atrophy type 1 (SMA1) have been published and none on sleep microstructure. The aim of this study was to analyze sleep architecture and microstructure in a group of infants with SMA1, compared with age- and sex-matched controls. METHODS: Twelve SMA1 patients (six males, mean age 5.9 months) and 10 controls (five males, mean age 4.8 months) underwent full polysomnography to evaluate their sleep architecture and microstructure by means of the cyclic alternating pattern (CAP). RESULTS: Compared with control children, SMA1 patients showed increased sleep latency and apnea/hypopnea index. CAP analysis revealed a significant increase in the percentage of A1 CAP subtypes, a reduction of that of A3 subtypes and of A2 and A3 indexes (number/h), indicating a dysfunction of the arousal system in these patients. CONCLUSION: The results indicate the presence of an abnormality of sleep microstructure in SMA1 patients, characterized by a reduction of A2 and A3 CAP subtypes. We hypothesize that SMA1 patients have reduced arousability during non-rapid eye movement sleep, which could be interpreted as additional evidence of central nervous system involvement in this disease.

Predicted and measured resting energy expenditure in children with spinal muscular atrophy 2.

We investigated in children with spinal muscular atrophy type 2 the consistency of 4 different equations for predicting resting energy expenditure (REE) compared with measured REE by using indirect calorimetry. In patients with spinal muscular atrophy type 2, measured REE was lower than predicted. We also found a correlation between energy consumption and motor skills.

Obstructive sleep apnea syndrome affects liver histology and inflammatory cell activation in pediatric nonalcoholic fatty liver disease, regardless of obesity/insulin resistance.

RATIONALE: Obstructive sleep apnea syndrome (OSAS) and nonalcoholic fatty liver disease (NAFLD) are frequently encountered in obese children. Whether OSAS and intermittent hypoxia are associated with liver injury in pediatric NAFLD is unknown. OBJECTIVES: To assess the relationship of OSAS with liver injury in pediatric NAFLD. METHODS: Sixty-five consecutive children with biopsy-proven NAFLD (age, mean ± SD, 11.7 ± 2.1 yr; 58% boys; body mass index z score, 1.93 ± 0.61) underwent a clinical-biochemical assessment and a standard polysomnography. Insulin sensitivity, circulating proinflammatory cytokines, markers of hepatocyte apoptosis (cytokeratin-18 fragments), and hepatic fibrogenesis (hyaluronic acid) were measured. Liver inflammatory infiltrate was characterized by immunohistochemistry for CD45, CD3, and CD163, surface markers of leukocytes, T cells, and activated macrophage/Kupffer cells, respectively. OSAS was defined by an apnea/hypopnea index (AHI) greater than or equal to 1 event/h, and severe OSAS was defined by an AHI greater than or equal to 5 events/h. MEASUREMENTS AND MAIN RESULTS: Fifty-five percent of children with NAFLD had nonalcoholic steatohepatitis (NASH), and 34% had significant (stage F ≥ 2) fibrosis. OSAS affected 60% of children with NAFLD; the presence and severity of OSAS were associated with the presence of NASH (odds ratio, 4.89; 95% confidence interval, 3.08-5.98; P = 0.0001), significant fibrosis (odds ratio, 5.91; 95% confidence interval, 3.23-7.42; P = 0.0001), and NAFLD activity score (ß, 0.347; P = 0.029), independently of body mass index, abdominal adiposity, metabolic syndrome, and insulin resistance. This relationship held also in nonobese children with NAFLD. The duration of hemoglobin desaturation (Sa(O2) < 90%) correlated with increased intrahepatic leukocytes and activated macrophages/Kupffer cells and with circulating markers of hepatocyte apoptosis and fibrogenesis. CONCLUSIONS: In pediatric NAFLD, OSAS is associated with biochemical, immunohistochemical, and histological features of NASH and fibrosis. The impact of hypoxemia correction on liver disease severity warrants evaluation in future trials.

Night-to-night consistency of at-home nocturnal pulse oximetry testing for obstructive sleep apnea in children.

RATIONALE: At-home nocturnal pulse oximetry has a high positive predictive value (PPV) for polysomnographically-diagnosed obstructive sleep apnea (OSA) but no studies have been published testing the night-to-night consistency of at-home nocturnal pulse oximetry for the evaluation of suspected OSA in children. We therefore determined the night-to-night consistency of nocturnal pulse oximetry as a diagnostic test for OSA in children. METHODS: We prospectively studied 148 children (96 male) aged 4.9 ± 2.4 (1.2-11.8) years, referred for suspected OSA. To evaluate night-to-night consistency, we compared an oximetry analysis method, the McGill Oximetry Score (MOS), from two consecutive at-home nocturnal pulse oximetry recordings. RESULTS: Pulse oximetry metrics were similar on the two nights. The MOS on the two nights showed excellent night-to-night consistency when analyzed as positive for OSA versus inconclusive, 143/148 (Spearman's correlation coefficient = 0.90). A more detailed analysis using four categories (MOS 1, 2, 3, and 4) of OSA severity showed very good night-to-night agreement, 133/148 (Spearman's correlation coefficient = 0.91). Variability was increased in children younger than 4 years of age compared to older children. CONCLUSIONS: Night-to-night consistency of nocturnal pulse oximetry as a diagnostic test for OSA showed excellent agreement. Night-to-night consistency of pulse oximetry, as analyzed by the MOS, for diagnosis and severity evaluation further validates this abbreviated testing method for pediatric OSA. Polysomnography (PSG) is required to rule in or rule out OSA in children if a single night oximetry testing is inconclusive.