Case 382 -- A baby boy with failure to thrive and respiratory insufficiency

Contributed by Lei Chen, MD, PhD, Alexis Carter, MD, Jeffrey A. Kant, MD, PhD
Published on line in March 2004

CLINICAL HISTORY:

This patient was born without any significant abnormalities. He was admitted to the hospital because of failure to thrive and myopathy of unknown etiology. He also had severe gastroesophageal reflux, tracheobronchomalacia, and respiratory insufficiency. During the hospital stay, patient underwent tracheostomy and required mechanical ventilation.

RELEVANT EXAMINATIONS:

1. Molecular testing for myotonic dystrophy:
   No abnormal increases in the CTG repeat were identified. Both of the patient's alleles were within the normal range.

2. Leg muscle biopsy:
   The microscopic findings are consistent with spinal muscular atrophy.

WE RECEIVED PERIPHERAL BLOOD FOR MOLECULAR TESTING TO CONFIRM SPINAL MUSCULAR ATROPHY (SMA).

RESULT:

Figure 1: PCR+RFLP for the area between intron 6 and exon 7.
Lane 1: molecular ladder; lane 2: this patient; lane 3-6: other patients; lane 7: positive control; lane 8: negative control

Figure 2: PCR+RFLP for the area between intron 7 and exon 8.
Lane 1: molecular ladder; lane 2: this patient; lane 3-6: other patients; lane 7: positive control; lane 8: negative control

FINAL DIAGNOSIS