A second maneuver to differentiate weakness in the calf muscles is to have the patient perform a unilateral heel raise while standing flatfooted on one foot only. The patient is permitted to balance with a hand, but most of the weight should be on that one foot. Then have the patient switch feet and perform the same test with the opposite foot. Most emergency physicians are not strong enough to use their arms to elicit a patient’s calf weakness. However, this maneuver uses the patient’s body weight and is very good at bringing out more subtle weakness.

In peripheral neuropathies the reflexes that are involved with the specific nerve are generally diminished or absent. Other reflexes will be normal. For central lesions, the patient may have hyporeflexia to areflexia, although there may also be hyperreflexia and clonus. Other important areas to evaluate are continence of urine and feces and impotence. Urinary and fecal incontinence nearly always indicate a central lesion.

Occasionally arm weakness or numbness from peripheral neuropathy or radiculopathy can be difficult to distinguish from stroke. As a rule, strokes do not cause limb pain, so associated pain typically excludes stroke as a cause. Paresthesias are common in radiculopathy and peripheral neuropathy but uncommon in stroke, which usually involves loss of sensation rather than hyperesthesias or paresthesias.

Case Presentation

A 4-month-old girl is brought in by her parents who are concerned because the child has been feeding poorly for the past several days. Her mother says that she switched from breast to bottle feeding 2 weeks ago and that her daughter “just doesn’t seem interested in eating.” Both parents state that the child has had one bowel movement in the past week, which is unusual for her, but they attributed that to the change in feedings. Other than being slightly less active than normal, there are no other complaints.

The child has an uncomplicated birth history and has been healthy since her delivery. There are no sick contacts in the household, and the child stays at home with her mother during the day. Her immunizations are current.

Vital signs are heart rate 132, respiratory rate 22, rectal temperature 37.3°C (99.2°F), and pulse oximetry 96% on room air. Physical examination reveals an ill-appearing child, lying quietly in her mother’s arms. The child is drooling and has some pooling of secretions in her mouth. She has coarse lung sounds, but she is not tachypneic or retracting. Her abdomen is soft and nontender. Most notably, the child has poor muscle tone and does not resist any part of the examination. She does not interact at all with you or her parents.

Botulism

Botulism is a paralytic disease caused by the bacteria Clostridium botulinum, which produces a heat-stable neurotoxin that engenders a diffuse peripheral neuropathy. There are three distinct varieties of the disease, food-borne, wound, and infantile, the last of which has more recently been termed intestinal botulism. All have similar clinical manifestations, but the manner of acquisition and the populations affected by each are unique.