Laryngeal stridor in children caused by reversible metabolic disease.

We report a case of a boy in his middle childhood who presented with inspiratory stridor and lactic acidosis and was subsequently diagnosed with partial biotinidase deficiency. Fibreoptic laryngoscope showed paradoxical vocal fold mobility.Partial biotidinase deficiency is an inherited disorder in which the body is unable to recycle the vitamin biotin. It may result in clinical consequences and can be easily treated with biotin but need a high index of suspicion to diagnose. The main symptoms include ataxia, seizures, hypotonia, psychomotor retardation, alopecia, skin rash, progressive deafness, optic atrophy and life-threatening episodes of metabolic acidosis. Laryngeal stridor is an uncommon presentation, but it is reversible in case of biotinidase deficiency. Invasive procedure like tracheostomy has not been shown to enhance outcomes.

Congenital cystic neck mass of thymic origin.

Neck masses are frequently seen in children. The differential diagnosis includes infectious, congenital and neoplastic lesions. We report a case of rare thymic neck mass in a boy in his middle childhood presented with a history of a left anterolateral neck mass not associated with fever, dysphagia or shortness of breath. The radiographic evaluation showed a picture of a thymopharyngeal duct cyst. Thymic remnant and thymopharyngeal duct cyst are caused by the failure of obliteration and might appear as a lateral neck mass in children. The most effective treatment for a thymopharyngeal duct cyst is total surgical excision. This particular case highlights the importance for clinicians to have a high index of suspicion for a broad differential diagnosis when evaluating paediatric patients who present with neck mass. Additionally, we emphasise the importance of consistently considering thymopharyngeal cyst as differential diagnosis.