A 5-Year Follow-Up of Triple-Seronegative Myasthenia Gravis Successfully Treated with Tacrolimus Therapy.

Seronegative myasthenia gravis (MG) is a generalized form of MG that is diagnosed on the basis of clinical symptoms, electrophysiological testing, and pharmacological responses, in the absence of a seropositive status for anti-acetylcholine receptor (AChR) antibodies. Generalized MG that is seronegative for anti-AChR, anti-muscle-specific kinase (MuSK), and anti-low density lipoprotein receptor related protein 4 (Lrp4) antibodies is known as triple-seronegative MG. We here describe a case of triple-seronegative MG in an 8-year-old boy.

Partial tandem duplication of GRIA3 in a male with mental retardation.

The genetic factors underlying mental retardation (MR) are very heterogeneous. Recent studies have identified a number of genes involved in MR, several of which lie on the X-chromosome, but the current understanding of the monogenic causes of MR is far from complete. Investigation of chromosomal rearrangements in patients with MR has proven particularly informative in the search for novel genes.

Immunoadsorption therapy in Guillain-Barré syndrome.

A 12-year-old boy rapidly developed Guillain-Barré syndrome (GBS) after Campylobacter jejuni enteritis. Electrophysiologic studies suggested that demyelination was dominant, and serum anti-C. jejuni and both IgG and IgM anti-GM1 antibodies were significantly elevated.

Motor nerve conduction studies on children with spinal muscular atrophy.

Median and posterior tibial motor nerve conduction studies were performed on 10 children with spinal muscular atrophy (SMA). Three patients with SMA type I, in whom rapid deterioration occurred, showed reduced motor nerve conduction velocity and a remarkably low M-wave amplitude in both nerves. In type II and III patients, the motor nerve conduction velocity was normal in the median nerve, although the M-wave amplitude was small in the tibial nerve.

Spinal cord MRI in neuro-Behçet's disease.

We report the case of a 10-year-old boy with neuro-Behçet's disease. Spinal cord MRI showed signal abnormalities in the cervical and thoracic cord, but cerebral CT and MRI revealed no abnormality.