While his acute hepatic and renal problems were so severe, he developed difficulty getting up from a chair or holding his arms above his head. He was also complaining of numbness and tingling in his feet. These symptoms were initially overlooked, but a CPK ordered later shows a value of 1103. Prior to continuing, please develop a differential diagnosis, and list each diagnosis in order of likelihood. The presence of generalized weakness with complaint of sensory alteration in the feet raises a number of possible diagnostic entities.
Generalized weakness can occur with primary muscle as well as primary nerve pathology.
It can also occur with diseases affecting the function of the neuromuscular junction although this type of weakness can show a fluctuating clinical variation depending on the level of previous activity. Isolated problems affecting the muscle or neuromuscular junction typically are not associated with sensory complaints. The presence of proximal muscle weakness clinically favors a diagnosis of myopathy but the complaint of numbness in the feet suggests peripheral neuropathy involving sensory afferents. Given the fact that the patient has been immobilized and recently ill, another possible explanation for the progressive muscular weakness could be muscular disuse atrophy. This tends to occur in patients who are at bedrest because of a severe illness.