eMedicine Specialties > Neurology > Pediatric Neurology

Benign Neonatal Convulsions: Differential Diagnoses & Workup

Author: Nancy Theresa Rodgers-Neame, MD, Assistant Professor, Department of Molecular Pharmacology and Physiology, University of South Florida; Director, Florida Comprehensive Epilepsy and Seizure Disorders Program
Contributor Information and Disclosures

Updated: Apr 8, 2009

Differential Diagnoses

Arteriovenous Malformations
Neonatal Injuries in Child Abuse
Aseptic Meningitis
Neonatal Meningitis
Epilepsy in Children with Mental Retardation
Neonatal Seizures
Febrile Seizures
Partial Epilepsies
Frontal Lobe Epilepsy
Tuberous Sclerosis
Infantile Spasm (West Syndrome)
Viral Encephalitis

Other Problems to Be Considered

Vitamin B-6 deficiency
Maternal drug abuse

Workup

Laboratory Studies

  • The reason for ordering tests in benign familial and idiopathic neonatal convulsions is to exclude the presence of any etiology for the seizures. The diagnosis of benign infantile convulsions of either type requires that no other explanation exist for the seizures. Order tests for individual patients with a plan for that patient in mind. While a "shotgun" approach is wasteful and unreasonable, it is also important not to miss a diagnosis of a treatable meningoencephalitis in the early stages or intracranial hemorrhage. Both of these conditions in neonates lack the typical findings observed in older infants and children, and the only early symptom may be seizures. Also entertain a healthy suspicion for child abuse in neonates, who often have just arrived home from the hospital following delivery. Review of basic screening laboratory studies performed at delivery may also be helpful.
    • Chemistries - Basic metabolic panel plus calcium, magnesium, phosphorus, thyroid function tests, and possibly B vitamin levels
    • Basic hematologic labs - CBC, prothrombin time, activated partial thromboplastin time
    • Lumbar puncture - Cerebrospinal fluid examination to exclude neonatal meningoencephalitis or occult blood
  • Any abnormalities found that are inconsistent with a diagnosis of benign neonatal convulsions require the appropriate further workup and treatment.

Imaging Studies

  • MRI or CT scan of the brain
    • Perform one or both of these tests in every patient with neonatal seizures to exclude structural lesions and intracranial hemorrhage.
    • An argument can be made that both are needed since CT scan yields better information on acute hemorrhage and skull fracture, and MRI shows better brain structural detail.

Other Tests

  • Electroencephalography
    • The classic EEG observed in 60% of patients with BINC is a rolandic discharge in the theta range that is alternating or discontinuous with intermixed sharp activity. Interhemispheric asymmetry is observed frequently; it is unresponsive to stimulation of any kind. This pattern often is termed theta pointu altérnant.3,7,29
    • The remaining patients with benign idiopathic neonatal convulsions have either a normal interictal EEG or focal abnormalities. The EEG during seizures is most often high-voltage (200-400 µV) generalized discharges, which may appear to have a focal onset.
  • In benign familial neonatal convulsions, the interictal EEG is most commonly normal (50-70% of patients). The theta pointu altérnant pattern also is observed but only in approximately 25% of patients. In a small percentage of patients, focal, often rolandic, discharges or spikes may be present.41,42,3
  • In selected patients, continuous video-EEG can be used to confirm behavioral events concordant with abnormal EEG and to confirm that treatment is effective. The state of the patient and improvement or deterioration can make decision-making easier and facilitate accurate communication with an often anxious family.7

More on Benign Neonatal Convulsions

Overview: Benign Neonatal Convulsions
Differential Diagnoses & Workup: Benign Neonatal Convulsions
Treatment & Medication: Benign Neonatal Convulsions
Follow-up: Benign Neonatal Convulsions
References
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References

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Further Reading

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Keywords

benign neonatal convulsions, second day seizures, benign neonatal seizures, benign familial neonatal convulsions, benign idiopathic neonatal convulsions, benign familial neonatal seizures, benign idiopathic neonatal seizures, fifth day disease, fifth day fits, seizure epilepsy treatment, symptoms, BFNC, BINC

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Contributor Information and Disclosures

Author

Nancy Theresa Rodgers-Neame, MD, Assistant Professor, Department of Molecular Pharmacology and Physiology, University of South Florida; Director, Florida Comprehensive Epilepsy and Seizure Disorders Program
Nancy Theresa Rodgers-Neame, MD is a member of the following medical societies: American Academy of Neurology, American Epilepsy Society, American Medical Women's Association, Society for Neuroscience, Southern Clinical Neurological Society, and Southern Medical Association
Disclosure: Nothing to disclose.

Medical Editor

Robert Baumann, MD, Program Director, Professor, Departments of Neurology and Pediatrics, University of Kentucky
Robert Baumann, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Pediatrics, American College of Epidemiology, American Epilepsy Society, and Child Neurology Society
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Kenneth J Mack, MD, PhD, Senior Associate Consultant, Department of Child and Adolescent Neurology, Mayo Clinic
Kenneth J Mack, MD, PhD is a member of the following medical societies: American Academy of Neurology, Child Neurology Society, Phi Beta Kappa, and Society for Neuroscience
Disclosure: Nothing to disclose.

CME Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Amy Kao, MD, Assistant Professor, Department of Pediatrics, Division of Pediatric Neurology, Department of Neurology, Oregon Health and Science University; Consulting Staff, Shriners Hospital for Children
Amy Kao, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Pediatrics, American Epilepsy Society, and Child Neurology Society
Disclosure: Nothing to disclose.

 
 
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