To evaluate for loss of skills, compare to what the child was doing 1/4 of his/her life ago, e.g., if a patient is 12 months, compare to what he/she was doing at 9 months.
Difficulty keeping up with peers (e.g., when sitting, walking, running, climbing stairs)
Review all developmental milestones, including social and language.
Family history
Though a negative family history does not rule out a genetic neuromuscular disease, a family history of neuromuscular disease may be critical in your evaluation.
Genetic neuromuscular disorders have a range of inheritance patterns, some of which allow transmission of a gene mutation through unaffected carriers and may result in an affected child with no previous family history. In addition, gene mutations that cause neuromuscular disorders may happen for the first time (de novo) in an affected child.
A complete family history should include information about at least 3 generations, a question about consanguinity in the parents, and a summary question about whether anyone else in the family had muscle concerns or weakness.
A three-generation family history in the pediatric context includes information on the child’s generation (i.e., siblings and cousins), the parents’ generation (i.e., the parents and their siblings and cousins), and the grandparents’ generation (i.e., the grandparents and their siblings). Asking about consanguinity (whether the parents are related) is important because consanguinity increases suspicion of an autosomal recessive disorder.
Neuromuscular diseases have different inheritance patterns.
Neuromuscular disorders may be autosomal dominant (passing from affected parent to child 50% of the time), autosomal recessive (passing from two unaffected, carrier parents to child 25% of the time), or X-linked (passing from an unaffected carrier mother to a child (almost always a son) 50% of the time).
For those diseases that are X-linked (such as Duchenne and Emery Dreifuss muscular dystrophies and some of the Charcot Marie Tooth disorders), pay particular attention to the extended maternal family (i.e., ask if the mother and maternal grandmother have brothers, and are there any concerns?).
Genetic/genomic tests (such as karyotype, microarray, or sequencing) may diagnose or identify risk for a neuromuscular disorder before there are obvious symptoms. Urgent telephone consultation with a geneticist or neurologist will inform an appropriate referral. MORE CLINICAL PEARLS
Taking a History
MORE CLINICAL PEARLS
