Harlequin syndrome in a pediatric population: a case series.

Harlequin syndrome is a rare condition, presenting with unilateral facial flushing and hyperhidrosis in response to physical exercise, heat or emotional stressors and has scarcely been reported in pediatric patients. It is caused by a dysfunction of vasomotor and sudomotor sympathetic fiber activity inhibiting the ability to flush on the affected side, causing the neurologically intact side to appear red. We present three pediatric cases of this uncommon syndrome, each of them of different origin and displaying distinct associated (neurological) symptoms, and review medical literature. Insight into the anatomical structure of the thoracocervical and facial sympathetic nervous system is pivotal as it dictates symptomatology. About half of Harlequin syndrome cases are complicated with ocular symptoms and a minority may be part of more extensive partial dysautonomias affecting facial sudomotor, vasomotor and pupillary responses, such as Holmes-Adie syndrome and Ross syndrome. Etiology is generally idiopathic, however, cases secondary to surgery, trauma or infection have been described. Considering its predominantly self-limiting nature, treatment is usually unnecessary and should be restricted to incapacitating cases.

Heterotopic ossifications and Charcot joints: Congenital insensitivity to pain with anhidrosis (CIPA) and a novel NTRK1 gene mutation.

Congenital insensitivity to pain with anhidrosis (CIPA), also known as hereditary sensory and autonomic neuropathy type IV (HSAN-IV), is a rare and severe autosomal recessive disorder. We report on an adult female patient whose clinical findings during childhood were not recognized as CIPA. There was neither complete anhidrosis nor a recognizable sensitivity to heat. Tumorlike swellings of many joints and skeletal signs of Charcot neuropathy developed in adolescence which, together with a history of self-mutilation, led to a clinical suspicion of CIPA confirmed by identification of a novel homozygous variant c.1795G > T in the NTRK1 gene in blood lymphocytes. Both parents were heterozygous for the mutation. The variant predicts a premature stop codon (p.Gly599Ter) and thus represents a pathogenic variant; the first reported in the Southeastern European population.

[Harlequin syndrome after scoliosis surgery]. / Harlekinsyndrom nach Skoliosechirurgie.

Harlequin syndrome is a rare combination of symptoms, characterized by unilateral facial anhidrosis and paleness on the affected side, becoming obvious by contralateral flushing mainly during sports activity. The syndrome is mostly idiopathic, however it is also described as a complication of thoracic surgery, i.e. superior lobectomy. Here, we report on two cases of Harlequin syndrome following scoliosis surgery at the cervicothoracic junction.

Harlequin syndrome following upper lobectomy.

A 58-year-old women developed unilateral facial flushing and sweating on the left side of her face immediately after a right thoracotomy upper lobectomy and paravertebral block. She was diagnosed with Harlequin syndrome in the absence of any other neurological signs or symptoms. She had recovered completely from this episode on follow-up.

NGF-dependent neurons and neurobiology of emotions and feelings: Lessons from congenital insensitivity to pain with anhidrosis.

NGF is a well-studied neurotrophic factor, and TrkA is a receptor tyrosine kinase for NGF. The NGF-TrkA system supports the survival and maintenance of NGF-dependent neurons during development. Congenital insensitivity to pain with anhidrosis (CIPA) is an autosomal recessive genetic disorder due to loss-of-function mutations in the NTRK1 gene encoding TrkA. Individuals with CIPA lack NGF-dependent neurons, including NGF-dependent primary afferents and sympathetic postganglionic neurons, in otherwise intact systems. Thus, the pathophysiology of CIPA can provide intriguing findings to elucidate the unique functions that NGF-dependent neurons serve in humans, which might be difficult to evaluate in animal studies. Preceding studies have shown that the NGF-TrkA system plays critical roles in pain, itching and inflammation. This review focuses on the clinical and neurobiological aspects of CIPA and explains that NGF-dependent neurons in the peripheral nervous system play pivotal roles in interoception and homeostasis of our body, as well as in the stress response. Furthermore, these NGF-dependent neurons are likely requisite for neurobiological processes of 'emotions and feelings' in our species.

Identification of a novel nonsense mutation of the neurotrophic tyrosine kinase receptor type 1 gene in two siblings with congenital insensitivity to pain with anhidrosis.

Objective To explore the aetiology of congenital insensitivity to pain with anhidrosis (CIPA) in two Chinese siblings with typical CIPA symptoms including insensitivity to pain, inability to sweat, and self-mutilating behaviours. Methods Clinical examination and genetic testing were conducted of all available family members, and the findings were used to create a pedigree. Mutation screening using PCR amplification and DNA Sanger sequencing of the entire neurotrophic tyrosine kinase receptor type 1 gene ( NTRK1) including intron-exon boundaries was used to identify mutations associated with CIPA. Results A novel nonsense mutation (c.7C > T, p. Arg3Ter) and a known splice-site mutation (c.851-33 T > A) were detected in NTRK1 and shown to be associated with CIPA. Conclusion Our findings expand the known mutation spectrum of NTRK1 and provide insights into the aetiology of CIPA.

Harlequin sign concomitant with Horner syndrome after anterior cervical discectomy: a case of intrusion into the cervical sympathetic system.

Harlequin syndrome is a rare autonomic disorder referring to the sudden development of flushing and sweating limited to one side of the face. Like Horner syndrome, associating miosis, ptosis, and anhidrosis, Harlequin syndrome is caused by disruption of the cervical sympathetic pathways. Authors of this report describe the case of a 55-year-old female who presented with both Harlequin sign and Horner syndrome immediately after anterior cervical discectomy (C6-7) with cage fusion and anterior spondylodesis. They discuss the pathophysiology underlying this striking phenomenon and the benign course of this condition. Familiarity with this unusual complication should be of particular interest for every specialist involved in cervical and thoracic surgery.

Exome sequencing identifies novel NTRK1 mutations in patients with HSAN-IV phenotype.

Hereditary sensory autonomic neuropathy type IV (HSAN-IV) is a rare autosomal recessive disorder that usually begins in infancy and is characterized by anhidrosis, insensitivity to noxious stimuli leading to self-mutilating behavior, and intellectual disability. HSAN-IV is caused by mutations in the neurotrophic tyrosine kinase receptor type 1 gene, NTRK1, encoding the high-affinity receptor of nerve growth factor (NGF) which maps to chromosome 1q21-q22. Patients with HSAN-IV lack all NGF-dependent neurons, the primary afferents and sympathetic postganglionic neurons leading to lack of pain sensation and the presence of anhidrosis, respectively. Herein, we report nine patients from nine unrelated families with HSAN-IV due to various mutations in NTRK1, five of which are novel. These are three missense and two nonsense mutations distributed in various domains of NTRK1 involved in binding of NGF. The affected patients had variable intellectual deficits, and some had delayed diagnosis of HSAN-IV. In addition to being the first report of HSAN-IV from the Arabian Peninsula, this report expands the mutational spectrum of patients with NTRK1 mutations and provides further insights for molecular and clinical diagnosis.

Foxc1 Ablated Mice Are Anhidrotic and Recapitulate Features of Human Miliaria Sweat Retention Disorder.

Sweat glands are critical for thermoregulation. The single tubular structure of sweat glands has a lower secretory portion and an upper reabsorptive duct leading to the secretory pore in the skin. Genes that determine sweat gland structure and function are largely unidentified. Here we report that a Fox family transcription factor, Foxc1, is obligate for appreciable sweat duct activity in mice. When Foxc1 was specifically ablated in skin, sweat glands appeared mature, but the mice were severely hypohidrotic. Morphologic analysis revealed that sweat ducts were blocked by hyperkeratotic or parakeratotic plugs. Consequently, lumens in ducts and secretory portions were dilated, and blisters and papules formed on the skin surface in the knockout mice. The phenotype was strikingly similar to the human sweat retention disorder miliaria. We further show that Foxc1 deficiency ectopically induces the expression of keratinocyte terminal differentiation markers in the duct luminal cells, which most likely contribute to keratotic plug formation. Among those differentiation markers, we show that Sprr2a transcription is directly repressed by overexpressed Foxc1 in keratinocytes. In summary, Foxc1 regulates sweat duct luminal cell differentiation, and mutant mice mimic miliaria and provide a possible animal model for its study.

A case of idiopathic pure sudomotor failure associated with prolonged high levels of serum carcinoembryonic antigen.

We report a case of idiopathic pure sudomotor failure (IPSF) in which serum carcinoembryonic antigen (CEA) levels elevated at onset, and remained high while anhidrosis lasted. We considered that changes in serum levels of CEA were related to the disease activity of IPSF.

Syndrome in question

Abstract Ross syndrome is a rare disease characterized by peripheral nervous system dysautonomia with selective degeneration of cholinergic fibers. It is composed by the triad of unilateral or bilateral segmental anhidrosis, deep hyporeflexia and Holmes-Adie's tonic pupil. The presence of compensatory sweating is frequent, usually the symptom that most afflicts patients. The aspects of the syndrome are put to discussion due to the case of a male patient, caucasian, 47 years old, with clinical onset of 25 years.

Evidence for hypohydrosis as clinical clue to diagnosis of Horner's syndrome.

A 59-year-old man presented with hypohydrosis in his left upper extremity and left hand, and experienced difficulty in gripping the steering wheel while driving. One year prior to admission, he had felt pain and/or paresthesias in his left anterior chest, left shoulder area and left periaxillar area, which corresponded to involvement of dermatomes in T1-T3. He was diagnosed with Horner's syndrome caused by lung tumour, which was located at the apical posterior wall along with the second to fourth ribs. The tumour interrupted sympathetic neurons at the T1-T4 level. The degree of hypohydrosis was successfully evaluated by the starch-iodine technique, dermal thermography and a skin surface hygrometer. After radiation therapy, hypohydrosis and pain or paresthesias improved partially, and he was discharged uneventfully.

Wet and dry hands after video-assisted thoracoscopic pleurectomy.

Damage to the thoracic sympathic chain is a rare complication of video-assisted thoracic surgery (VATS) pleurectomy. We report our experience with a patient who underwent parietal pleurectomy and bullectomy by VATS and postoperatively suffered from palmar anhydrosis and compensatory controlateral hyperhidrosis. The possible mechanisms of nerve damage and various techniques of performing pleurectomy are discussed.

Muscle and skin sympathetic activities in Ross syndrome.

OBJECTIVES: Ross syndrome (RS) is a rare degenerative disorder characterized by tonic pupil, areflexia and anhydrosis. The underlying lesion affects postganglionic skin sympathetic nerve fibers whereas the postganglionic muscle sympathetic branch is thought to be spared. Microneurography explores both skin and muscle peripheral sympathetic branches and it does not usually detect peripheral sympathetic outflow in either branch in chronic autonomic failure syndromes. The aim of this study was to record sympathetic activity by microneurography for the first time in RS patients to confirm the selective involvement of skin sympathetic nerve activity (SSNA) with spared muscle sympathetic nerve activity (MSNA). METHODS: We studied seven patients (49 ± 14 years, four males) with a typical clinical picture and skin biopsy findings. Patients underwent cardiovascular reflexes and microneurography from the peroneal nerve (anhydrotic skin) to record MSNA, SSNA and the corresponding organ effector responses (skin sympathetic response-SSR and skin vasomotor response-SVR) in the same innervation field. The absence of sympathetic bursts was established after exploring at least three different corresponding nerve fascicles. Twenty age-matched healthy subjects served as controls. RESULTS: RS patients complained of diffuse anhydrosis and they showed tonic pupil and areflexia. Cardiovascular reflexes were normal. All patients displayed absent SSNA, SSR and SVR whereas MSNA was always recorded showing normal characteristics. CONCLUSION: Microneurographic study of sympathetic activity from affected skin confirmed the selective involvement of skin sympathetic activity with spared muscle sympathetic activity and it may represent the neurophysiological hallmark of the disease. SIGNIFICANCE: Microneurography together with clinical and skin biopsy findings may contribute to RS diagnosis. Our data also suggest that autonomic damage in RS does not involve cardiovascular activity.