A 2-year-old girl is brought to the clinic due to irritability for 2 weeks. She has also had intermittent fevers and poor appetite. The patient has had no cough, rhinorrhea, vomiting, or diarrhea. She has no chronic medical conditions and takes no medications. Her parents have a history of cold sores but have had no recent outbreaks. The family recently went camping but has not traveled internationally. Temperature is 36.7 C (98 F), blood pressure is 90/50 mm Hg, pulse is 104/min, and respirations are 22/min. On examination, the patient is tired-appearing and pale. The right upper eyelid is drooping and the right pupil is constricted. When the patient cries, only the left side of the face appears flushed. Cardiopulmonary examination is unremarkable. The abdomen is soft, nontender, and nondistended with no palpable masses. She has no dysmetria when reaching for objects and has full strength in all extremities. MRI reveals a cervical paravertebral mass. Which of the following is the most likely diagnosis?

Question

A 2-year-old girl is brought to the clinic due to irritability for 2 weeks.  She has also had intermittent fevers and poor appetite.  The patient has had no cough, rhinorrhea, vomiting, or diarrhea.  She has no chronic medical conditions and takes no medications.  Her parents have a history of cold sores but have had no recent outbreaks.  The family recently went camping but has not traveled internationally.  Temperature is 36.7 C (98 F), blood pressure is 90/50 mm Hg, pulse is 104/min, and respirations are 22/min.  On examination, the patient is tired-appearing and pale.  The right upper eyelid is drooping and the right pupil is constricted.  When the patient cries, only the left side of the face appears flushed.  Cardiopulmonary examination is unremarkable.  The abdomen is soft, nontender, and nondistended with no palpable masses.  She has no dysmetria when reaching for objects and has full strength in all extremities.  MRI reveals a cervical paravertebral mass.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec25c8_d58b_fa11_bc81_03b2b454227c_MD0003_00 This patient has Horner syndrome in the setting of a cervical paravertebral mass, findings suspicious for neuroblastoma. Neuroblastoma is the most common extracranial solid tumor of childhood, with a median age <2. The tumor arises from neural crest cells, which are precursors to the sympathetic ganglia and adrenal medulla, the latter of which is the most common site of neuroblastoma. Tumor involvement of the cervical paravertebral sympathetic chain can lead to ipsilateral Horner syndrome (ie, ptosis, miosis, anhidrosis). Although sweating is often difficult to appreciate in young children, absent facial flushing (ie, "harlequin" sign) can be observed in anhidrotic areas, as seen in this patient. Horner syndrome Urine and serum catecholamines (vanillylmandelic acid and homovanillic acid) are elevated in the majority of patients; tissue biopsy is required for definitive diagnosis. (Choices A and B) Herpes simplex virus and Lyme disease can affect the facial nerve and cause Bell palsy, resulting in unilateral facial droop. Pupillary response and sweating/flushing are not affected in Bell palsy. (Choices C and F) Medulloblastomas and pilocytic astrocytomas are childhood brain tumors that commonly arise in the cerebellum. Presentation typically involves ataxia and dysmetria, not Horner syndrome. (Choice E) Pheochromocytomas are catecholamine-secreting tumors that most commonly arise from the adrenal medulla and usually occur in adults. Typical findings include an abdominal mass, hypertension, and episodes of headache, diaphoresis, and tachycardia, which are not seen in this patient. Educational objective: Neuroblastoma arises from neural crest cells, which are precursors to the sympathetic ganglia and adrenal medulla. Neuroblastoma arising in the cervical paravertebral sympathetic chain can present as isolated Horner syndrome (ie, ptosis, miosis, anhidrosis). References: Neuroblastoma pathogenesis: deregulation of embryonic neural crest development. (http://www.ncbi.nlm.nih.gov/pubmed/29222693) Incidence of pediatric Horner syndrome and the risk of neuroblastoma: a population-based study. (http://www.ncbi.nlm.nih.gov/pubmed/20212203)

A 2-Year-Old Girl Is Brought to the Clinic Due to Irritability