Congenital Central Hypoventilation Syndrome: A Case-Based Learning Opportunity for Neonatal Clinicians.

Congenital central hypoventilation syndrome (CCHS) is a rare and sporadic neurocristopathy characterized by alveolar hypoventilation and autonomic nervous system dysfunction. CCHS manifests quickly after birth, initially as respiratory distress. Mortality risk is estimated at 38 percent, with a median age of death of three months of age. A timely and accurate diagnosis is critical. Genetic testing for PHOX2B gene mutations is necessary to confirm the diagnosis; however, laboratory turnaround time often imposes an additional 7-14-day waiting period on an often anxious family. Neonatal clinicians should recognize that families require disease-specific education, emotional support, and time to rehearse daily caregiving in preparation for discharge. Therefore, this article presents the key clinical, pathophysiologic, and diagnostic factors, as well as a discussion of discharge needs. A case report of an infant, born to parents with no known history of CCHS, is included as a case-based learning opportunity for readers.

Mutations in MYO1H cause a recessive form of central hypoventilation with autonomic dysfunction.

BACKGROUND: Congenital central hypoventilation syndrome (CCHS) is a rare life-threatening disorder of respiratory and autonomic regulation. It is classically caused by dominant mutations in the transcription factor PHOX2B. The objective of the present study was to identify the molecular cause of a recessive form of central hypoventilation with autonomic dysfunction. METHODS: Here, we used homozygosity mapping and whole-genome sequencing in a consanguineous family with CCHS in combination with functional analyses in CRISPR/Cas9 engineered mice. RESULTS: We report on a consanguineous family with three affected children, all tested PHOX2B mutation negative, presenting with alveolar hypoventilation and symptoms of autonomic dysregulation. Whole-genome sequencing revealed a homozygous frameshift mutation in exon 25 of the MYO1H gene (c.2524_2524delA) segregating with the phenotype in the family. MYO1H encodes for the unconventional myosin IH, which is thought to function as a motor protein in intracellular transport and vesicle trafficking. We show that Myo1h is broadly expressed in the mouse lower medulla, including the CO2-sensitive Phox2b+ retrotrapezoid neurons. To test the pathogenicity of the variant, we engineered two Myo1h mutant mouse strains: the first strain (Myo1h*) resembling the human mutation and the second being a full knock-out (Myo1hFS ). Whole-body plethysmography studies in Myo1h* newborns with the re-engineered human mutation revealed hypoventilation and a blunted response to CO2, recapitulating the breathing phenotype observed in the kindred. CONCLUSIONS: Our results identify MYO1H as an important gene in CO2 sensitivity and respiratory control and as the cause of a rare recessive form of congenital central hypoventilation.

Central alveolar hypoventilation (Ondine's curse) caused by megadolichobasilar artery.

Central alveolar hypoventilation (CAH) syndrome is a clinical condition that is characterized by the loss of automatic breathing, particularly during sleep. Most forms in adults are caused by brainstem ischemia, mass, infection, demyelinating disease, or anoxic-ischemic damage. We present a case of a fatal symptomatic acquired CAH syndrome caused by megadolichobasilar artery. A 62-year-old man with pre-existing vascular dementia suffered an acute posterior stroke. During stroke care, long episodes of hypopnea and apnea were observed which responded well to verbal reminders. During an unobserved episode, the patient was found unresponsive, with chemical signs of prolonged hypoventilation not explainable by cardiopulmonary disease. A diaphragmatic pacemaker, assisted ventilation, and repeated resuscitation were refused by the patient, who died some days later. CAH is a rare complication that can occur in patients with megadolichobasilar artery.

Decannulation in congenital central hypoventilation syndrome.

RATIONALE: Patients with congenital central hypoventilation syndrome (CCHS) require long-term ventilation to ensure gas exchange and to prevent deleterious consequences for neurocognitive development. Two ventilation modes may be used for these patients depending on their tolerance, one invasive by tracheostomy and the other noninvasive (NIV). For patients who have undergone a tracheostomy, transition to NIV is possible when they meet predefined criteria. Identifying the conditions favorable for weaning from a tracheostomy is critical for the success of the process. OBJECTIVE: The aim of the study was to share our experience of decannulation in a reference center; we hereby describe the modality of ventilation and its effect on nocturnal gas exchange before and after tracheostomy removal. METHODS: Retrospective observational study at Robert Debré Hospital over the past 10 years. The modalities of decannulation and transcutaneous carbon dioxide recordings or polysomnographies before and after decannulation were collected. RESULTS: Sixteen patients underwent decannulation following a specific procedure for transition from invasive to NIV. All decannulations were successful. The median age at decannulation was 12.6 [9.4; 14.1] years. Nocturnal gas exchange was not significantly different before and after decannulation, while expiratory positive airway pressure and inspiratory time increased significantly. An oronasal interface was chosen in two out of three patients. The median duration of hospital stay for decannulation was 4.0 [3.8; 6.0] days. CONCLUSION: Our study underlines that decannulation and transition to NIV are achievable in CCHS children using a well-defined procedure. Patient preparation is crucial to the success of the process.

Ondine's curse: clinical presentation with diaphragmatic pacing and spontaneous respiratory recovery. Illustrative case.

BACKGROUND: The complexity of posterior fossa surgery can often lead to rare complications due to the anatomy involved. Vestibular schwannoma resection is a common pathology in the posterior fossa, often requiring surgical intervention. Given the proximity of this space to the brainstem, cranial nerve VII/VIII complex, and posterior inferior cerebellar artery (PICA), neurovascular complications are not infrequent. A rare vascular complication from this surgical approach is a lateral medullary infarction from injury to the lateral medullary segment of the proximal PICA, leading to central hypoventilation syndrome (CHS). OBSERVATIONS: This report presents a unique case of a 51-year-old man who underwent a retrosigmoid craniectomy for resection of a vestibular schwannoma. Following surgery, the patient was unable to be weaned off the ventilator and was noted to become apneic while he slept, a clinical picture consistent with Ondine's curse. LESSONS: This report discusses the anatomical considerations of this surgical corridor leading to this complication and the management of a patient with acquired Ondine's curse and reviews the scarce literature on this uncommon cause of acquired CHS.

Case report: Central alveolar hypoventilation in a survivor of cardiopulmonary arrest.

Introduction: Ondine's curse is a rare respiratory disorder that is characterized by central alveolar hypoventilation (CAH) during sleep. It is most commonly congenital. However, it can also be acquired very rarely. Herein, we report a young survivor who developed CAH following cardiopulmonary arrest. Case presentation: A 35-year-old man was admitted to the Intensive Care Unit following unwitnessed cardiopulmonary arrest. Following resuscitative interventions, he remained comatose. Early diagnostic testing showed elevated neuronal specific enolase (28.7 ng/ml), absent cortical responses on evoked potential testing and MRI evidence of restricted diffusion in the cerebellum, hippocampi, juxtacortical white matter, superior cerebellar peduncles, dorsal pons, dorsolateral medulla, and upper cervical spinal cord. Ten days following admission, the patient remained comatose and underwent tracheostomy. He subsequently began to emerge from coma but had persistent unexplained hypotension and bradypnea necessitating ongoing vasopressor and respiratory support. Repeat MRI on hospital day 40 revealed residual FLAIR hyperintensities in the medulla within the nucleus tractus solitarius (NTS). After being discharged to long-term acute care facility, he was successfully liberated from mechanical ventilation 70 days post arrest. Conclusion: We report the first survivor of cardiopulmonary arrest who was complicated by CAH and hypotension with MRI verified ischemic injury to the bilateral NTS regions. Despite this injury, ventilator and vasopressor dependency resolved over a period of 10 weeks. Our case highlighted the essential functions of NTS in regulating the respiratory and cardiovascular systems.

[Alone or combined with serotoninergic agents, the progestins of the gonane family may represent a therapeutic alternative for Ondine's curse syndrome]. / Les progestatifs de la famille des gonanes, seuls ou associés à des agents sérotoninergiques, une éventuelle piste thérapeutique pour le syndrome d'Ondine.

Central hypoventilation syndromes such as Ondine's curse are rare neurorespiratory diseases associated with dysregulation of the vegetative (or autonomous) nervous system. They are characterized by a defect in the automatic control of ventilation, with a severe reduction or even the absence of CO2/H+ chemosensitivity. As no effective pharmacotherapy currently exists, lifelong mechanical ventilation is the only available treatment for patients suffering from these syndromes. In this context, clinical observation and studies in animal models suggest that gonane progestins, alone or in combination with serotonergic agents, could constitute a therapeutic alternative.

Ondine's curse, a fatal infarction diagnosed by polysomnography and saved by ventilation: a case report.

BACKGROUND: Lateral medullary syndrome causing Ondine's curse is a rare yet fatal brainstem infarction. Any patient presenting with lateral medulla infarction ought to be well observed and a polysomnography must be ordered for him. CASE PRESENTATION: A patient presenting with Ondine's curse is dealt with through polysomnography as a diagnostic procedure that was followed by tracheostomy with portable ventilator and cardiac pacemaker as a therapeutic maneuver which ultimately preserved his life. CONCLUSION: Lateral medullary syndrome infarct could be a life-threatening stroke if not diagnosed and managed properly.

A Case of Medullary Infarct Causing Central Alveolar Hypoventilation.

Central alveolar hypoventilation (CAH) is a rarely encountered pathology characterized by decreased ventilation due to the loss of autonomic control. Most cases present at birth, as it can be a rare genetic disorder, but we aim to show that it can occur as an acquired condition too. We present a case of a 65-year-old man who developed CAH as a sequela of an ischemic stroke and discuss possible pathophysiology. Increasing awareness and an early detection of this condition can have a significant effect on morbidity and mortality of patients.

Ondine's Curse in Frontotemporal Dementia with Parkinsonism Linked to Chromosome 17 Caused by MAPT Variants.

BACKGROUND: "Ondine's curse" or central hypoventilation, induces an apparently spontaneous failure of automatic respiratory drive, henceforth necessitating a conscious effort to breathe and sleep induced hypoventilation. It is typically seen in congenital central hypoventilation syndrome, but may be acquired. OBJECTIVES: To highlight Ondine's curse as part of frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17) secondary to microtubule associated protein tau (MAPT) variants. METHODS: We describe the clinical and neuropathological findings in two patients with fatal Ondine's curse associated with FTDP-17 and secondary to MAPT variants (FTDP-17t). We discuss neuroanatomical correlates. We review two prior reports of central hypoventilation associated with MAPT variants suggesting that Ondine's curse occurs uncommonly in FTDP-17t. RESULTS: Despite variants affecting different regions of MAPT and a degree of heterogeneity in pathological findings, the patients reviewed all experienced central hypoventilation during their disease course. CONCLUSION: Tauopathy should be considered in patients with adult-onset Ondine's curse.

Network Localization of Central Hypoventilation Syndrome in Lateral Medullary Infarction.

BACKGROUND AND PURPOSE: The brainstem plays a key role in the control of respiration. Strokes involving the lateral medulla can rarely produce a central hypoventilation syndrome (CHS) characterized by loss of automatic respiration called Ondine's curse. In this study, we investigated the neuroanatomical correlates of CHS in patients with lateral medullary infarction (LMI). METHODS: Cases of CHS following LMI were identified from searching our medical records and literature. Voxel-based lesion-symptom mapping and lesion network-symptom-mapping (LNSM) analysis was performed to identify the regions connected to the lesion sites based on normative functional connectome data. RESULTS: Sixteen patients with CHS and 32 controls were included. The ventro-lateral region of the rostral medulla showed a significant association with CHS. LNSM analysis showed connections of this region to the rostral ventro-lateral medulla and caudal pons. CONCLUSIONS: In patients with LMI, disruption of the respiratory control network, at the level of ventro-lateral region of the rostral medulla, could result in CHS.

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.

Spinal anesthesia and postoperative epidural analgesia in a patient with congenital central hypoventilation syndrome -a case report.

Background: Congenital central hypoventilation syndrome (CCHS) is a rare disorder characterized by alveolar hypoventilation and autonomic dysregulation. Patients with CCHS have adequate ventilation while awake but exhibit hypoventilation while asleep. More severely affected patients exhibit hypoventilation both when awake and when asleep. Case: Here, we report a case of successful spinal anesthesia and postoperative epidural analgesia in a patient with CCHS who underwent orthostatic surgery. Conclusions: In patients with CCHS, anesthesia is used with the goal of minimizing respiratory depression to avoid prolonged mechanical ventilation. Regional anesthesia should be considered where appropriate. Continuous oxygen saturation and end-tidal carbon dioxide monitoring must be available.

Neonatal Congenital Central Hypoventilation Syndrome: Why We Should not Sleep on it. Literature Review of Forty-two Neonatal Onset Cases.

Congenital Central Hypoventilation Syndrome (CCHS), also referred with the expression "Ondine's Curse", is a rare genetic life-long disease resulting from the mutation of PHOX2B gene on chromosome 4p12.3. CCHS represents an autonomic nervous system disorder; its more fearsome manifestation is central hypoventilation, due to a deficient response of chemoreceptors to hypercapnia and hypoxia. Several associated symptoms can occur, such as pupillary anomalies, arrhythmias, reduced heart rate variability, esophageal dysmotility, and structural comorbidities (Hirschsprung's Disease or neural crest tumours). CCHS typical onset is during the neonatal period, but cases of delayed diagnosis have been reported; moreover, both sporadic or familial cases can occur. In preterm newborns, asphyxia and typical prematurity-related findings may overlap CCHS clinical manifestations and make it harder to formulate a correct diagnosis. The early recognition of CCHS allows appropriate management, useful to reduce immediate and long- term consequences.

Current Perspectives for the use of Gonane Progesteronergic Drugs in the Treatment of Central Hypoventilation Syndromes.

BACKGROUND: Central alveolar hypoventilation syndromes (CHS) encompass neurorespiratory diseases resulting from congenital or acquired neurological disorders. Hypercapnia, acidosis, and hypoxemia resulting from CHS negatively affect physiological functions and can be lifethreatening. To date, the absence of pharmacological treatment implies that the patients must receive assisted ventilation throughout their lives. OBJECTIVE: To highlight the relevance of determining conditions in which using gonane synthetic progestins could be of potential clinical interest for the treatment of CHS. METHODS: The mechanisms by which gonanes modulate the respiratory drive were put into the context of those established for natural progesterone and other synthetic progestins. RESULTS: The clinical benefits of synthetic progestins to treat respiratory diseases are mixed with either positive outcomes or no improvement. A benefit for CHS patients has only recently been proposed. We incidentally observed restoration of CO2 chemosensitivity, the functional deficit of this disease, in two adult CHS women by desogestrel, a gonane progestin, used for contraception. This effect was not observed by another group, studying a single patient. These contradictory findings are probably due to the complex nature of the action of desogestrel on breathing and led us to carry out mechanistic studies in rodents. Our results show that desogestrel influences the respiratory command by modulating the GABAA and NMDA signaling in the respiratory network, medullary serotoninergic systems, and supramedullary areas. CONCLUSION: Gonanes show promise for improving ventilation of CHS patients, although the conditions of their use need to be better understood.

Congenital central hypoventilation syndrome: An overview of etiopathogenesis, associated pathologies, clinical presentation, and management.

Congenital central hypoventilation syndrome (CCHS), known colloquially as Ondine's curse, is a rare disorder characterized by impaired autonomic control of breathing during sleep from the loss of vagal input and diminished sensitivity of CO2 receptors in the medulla. CCHS correlates to the malformation of the neural crest located in the brainstem; this consequently affects the loss of sensitivity of CO2 chemoreceptors, bringing about hypoventilation during sleep. The primary cause of CCHS is the mutation of the paired-like homeobox PHO2XB gene, found in 90% of the patients. This mutation not only affects breathing but also drives neurological abnormalities such as autonomic and neurocognitive dysfunction. Though typically congenital, there have been late-onset (i.e., acquired) cases reported. It is vital for physicians and clinicians to be able to diagnose CCHS due to its similar presentation to other syndromes and disorders, which may cause it to be misdiagnosed and may account for its deleterious effects. CCHS can lead to a constellation of symptoms, and consideration of diseases that present concomitantly with CCHS affords us a better understanding of the etiology of this illness. Although a rare syndrome, we aim to review the current literature to emphasize the pathogenesis, etiology, clinical presentation, symptoms, diagnosis, and current treatment methods of CCHS for clinicians to better identify and understand this condition.

Normal sleep on mechanical ventilation in adult patients with congenital central alveolar hypoventilation (Ondine's curse syndrome).

BACKGROUND: The purpose of this study was to describe the sleep structure (especially slow wave sleep) in adults with congenital central hypoventilation syndrome (CCHS), a rare genetic disease due to mutations in the PHOX2B gene. Fourteen patients aged 23 (19.0; 24.8) years old (median [1rst-3rd quartiles]) with CCHS underwent a sleep interview and night-time attended polysomnography with their ventilatory support. Their sleep variables were compared to those collected in 15 healthy control subjects matched for age, sex and body mass index. RESULTS: The latency to N3 sleep was shorter in patients (26.3 min [24.0; 30.1]) than in controls (49.5 min [34.3; 66.9]; P = 0.005), and sleep onset latency tended to be shorter in patients (14.0 min [7.0; 20.5]) than in controls (33.0 min [18.0; 49.0]; P = 0.052). Total sleep time, sleep stage percentages, sleep fragmentation as well as respiratory and movement index were within normal ranges and not different between groups. CONCLUSIONS: Normal sleep in adult patients with CCHS and adequate ventilator support indicates that the PHOX2 gene mutations do not affect brain sleep networks. Consequently, any complaint of disrupted sleep should prompt clinicians to look for the usual causes of sleep disorders, primarily inadequate mechanical ventilation. Shorter N3 latency may indicate a higher need for slow wave sleep, to compensate for the abnormal respiratory-related cortical activity during awake quiet breathing observed in patients with CCH.

Dental treatment of a child with congenital central hypoventilation syndrome.

BACKGROUND: Congenital Central Hypoventilation Syndrome (CCHS) is a rare condition combining respiratory hypoventilation with symptoms of autonomic dysregulation. Management of patients requires both medical and dental expertise to achieve a successful outcome. The aim of this paper is to present the dental management of a child diagnosed with CCHS, without pharmacological measures and in cooperation with medical expertise. CASE REPORT: A 7-year-old girl was referred to a private dental practice with the chief complaints being pain and poor aesthetics. The child had been diagnosed with CCHS since infancy and had undergone several courses of medication. Although the patient was uncooperative, the paediatric pulmonologist advised against general anaesthesia. As a result, she was treated in the operating theater (OT) without sedatives, being monitored throughout the entire procedure. A total of eight primary teeth needed dental treatment (3 were restored, 4 were extracted and 1 was restored with a preformed metal crown). A mandibular lingual holding arch was placed, two weeks later. FOLLOW-UP: The patient was seen after 6 months and 1 year. Her oral hygiene had improved significantly and her mother reported that the child ate better, brushed her teeth on a daily basis and was careful with dietary habits. CONCLUSION: The collaboration between medical experts and a paediatric dentist was of crucial importance. The use of basic behaviour management techniques in conjunction with monitoring the patient's vital signs led to a successful outcome and an improvement in the behaviour of the patient.

Congenital central hypoventilation syndrome associated with Hirschsprung's Disease: case report and literature review. / Síndrome de hipoventilação central congênita associada à doença de Hirschsprung: relato de caso e revisão de literatura.

OBJECTIVE: To report the case of a newborn with recurrent episodes of apnea, diagnosed with Congenital Central hypoventilation syndrome (CCHS) associated with Hirschsprung's disease (HD), configuring Haddad syndrome. CASE DESCRIPTION: Third child born at full-term to a non-consanguineous couple through normal delivery without complications, with appropriate weight and length for gestational age. Soon after birth he started to show bradypnea, bradycardia and cyanosis, being submitted to tracheal intubation and started empiric antibiotic therapy for suspected early neonatal sepsis. During hospitalization in the NICU, he showed difficulty to undergo extubation due to episodes of desaturation during sleep and wakefulness. He had recurrent episodes of hypoglycemia, hyperglycemia, metabolic acidosis, abdominal distension, leukocytosis, increase in C-reactive protein levels, with negative blood cultures and suspected inborn error of metabolism. At 2 months of age he was diagnosed with long-segment Hirschsprung's disease and was submitted to segment resection and colostomy through Hartmann's procedure. A genetic research was performed by polymerase chain reaction for CCHS screening, which showed the mutated allele of PHOX2B gene, confirming the diagnosis. COMMENTS: This is a rare genetic, autosomal dominant disease, caused by mutation in PHOX2B gene, located in chromosome band 4p12, which results in autonomic nervous system dysfunction. CCHS can also occur with Hirschsprung's disease and tumors derived from the neural crest. There is a correlation between phenotype and genotype, as well as high intrafamilial phenotypic variability. In the neonatal period it can simulate cases of sepsis and inborn errors of metabolism.

Sleep Apnea Syndrome after Posterior Fossa Surgery: A Case of Acquired Ondine's Curse.

INTRODUCTION: Ondine's Curse is a catastrophic but rare condition in adults. It is referred to as a congenital or acquired condition, in which the patient cannot breathe automatically while asleep. Acquired causes of this disease can be any cause affecting the ventrolateral part of the medulla, which is considered to be the breathing center in humans.  CASE REPORT: A 51-year-old woman, with ataxia and the symptoms and signs of rising Intra-Cranial Pressure, who underwent ventriculoperitoneal shunting and removal of tumour, developed episodic apnea during sleep after surgery and hypercapnia when awake. In her post-operative CT scan, some fine spots of hypodensity in the left lateral part of the medulla were observed. She was managed pharmacologically and underwent tracheotomy. After 50 days, she was discharged from the hospital when she was able to breathe normally. CONCLUSION: Having experience with this condition after resection of a fourth ventricle tumor, it was found that Ondine's Curse can be considered as one of the complications of posterior fossa surgery and is curable by proper management.