Atypical Cyanotic Breath-Holding Spells in an Infant With 16p11.2 Microdeletion Syndrome

Health supervision for children and adolescents with 16p11.2 deletion syndrome

Rare genetic conditions are challenging for the primary care provider to manage without proper guidelines. This clinical review is designed to assist the pediatrician, family physician, or internist in the primary care setting to manage the complexities of 16p11.2 deletion syndrome. A multidisciplinary medical home with the primary care provider leading the care and armed with up-to-date guidelines will prove most helpful to the rare genetic patient population. A special focus on technology to fill gaps in deficits, review of case studies on novel medical treatments, and involvement with the educational system for advocacy with an emphasis on celebrating diversity will serve the rare genetic syndrome population well.

The Phenotypic Spectrum of PRRT2-Associated Paroxysmal Neurologic Disorders in Childhood

Pathogenic variants in PRRT2, encoding the proline-rich transmembrane protein 2, have been associated with an evolving spectrum of paroxysmal neurologic disorders. Based on a cohort of children with PRRT2-related infantile epilepsy, this study aimed at delineating the broad clinical spectrum of PRRT2-associated phenotypes in these children and their relatives. Only a few recent larger cohort studies are on record and findings from single reports were not confirmed so far. We collected detailed genetic and phenotypic data of 40 previously unreported patients from 36 families. All patients had benign infantile epilepsy and harbored pathogenic variants in PRRT2 (core cohort). Clinical data of 62 family members were included, comprising a cohort of 102 individuals (extended cohort) with PRRT2-associated neurological disease. Additional phenotypes in the cohort of patients with benign sporadic and familial infantile epilepsy consist of movement disorders with paroxysmal kinesigenic dyskinesia in six patients, infantile-onset movement disorders in 2 of 40 individuals, and episodic ataxia after mild head trauma in one girl with bi-allelic variants in PRRT2. The same girl displayed a focal cortical dysplasia upon brain imaging. Familial hemiplegic migraine and migraine with aura were reported in nine families. A single individual developed epilepsy with continuous spikes and waves during sleep. In addition to known variants, we report the novel variant c.843G>T, p.(Trp281Cys) that co-segregated with benign infantile epilepsy and migraine in one family. Our study highlights the variability of clinical presentations of patients harboring pathogenic PRRT2 variants and expands the associated phenotypic spectrum.

Breath-Holding Spells in Pediatrics: A Narrative Review of the Current Evidence

BACKGROUND

Breath-holding spells are common, frightening, but fortunately benign events. Familiarity with this condition is important so that an accurate diagnosis can be made.

OBJECTIVE

To familiarize physicians with the clinical manifestations, diagnosis, evaluation, and management of children with breath-holding spells.

METHODS

A PubMed search was completed in Clinical Queries using the key term "breath-holding spells". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. Only papers published in the English literature were included in this review. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Breath-holding spells affect 0.1 to 4.6% of otherwise healthy young children. The onset is usually between 6 and 18 months of age. The etiopathogenesis is likely multifactorial and includes autonomic nervous system dysregulation, vagally-mediated cardiac inhibition, delayed myelination of the brain stem, and iron deficiency anemia. Breath-holding spells may be cyanotic or pallid. The former are usually precipitated by anger or frustration while the latter are more often precipitated by pain or fear. In the cyanotic type, the child usually emits a short, loud cry, which leads to a sudden involuntary holding of the breath in forced expiration. The child becomes cyanosed, rigid or limp, followed by a transient loss of consciousness, and a long-awaited inspiration and resolution of the spell. In the pallid type, crying may be minimal or "silent". The apneic period in the pallid type is briefer than that in the cyanotic type prior to the loss of consciousness and posture. The episode in the pallid type then proceeds in the same manner as a cyanotic spell except that the child in the pallid type develops pallor rather than cyanosis. In both types, the entire episode lasts approximately 10 to 60 seconds. The spells usually disappear spontaneously by 5 years of age.

CONCLUSION

Although breath-holding spells are benign, they can be quite distressing to the parents. Confident reassurance and frank explanation are the cornerstones of treatment. Underlying cause, if present, should be treated. Interventions beyond iron supplementation may be considered for children with severe and frequent breath-holding spells which have a strong impact on the lifestyle of both the child and family.