Muscle weakness and Neuropathy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Differential Diagnosis of Muscle weakness and Neuropathy

Organ system	Disease	Symptoms												History	Physical Examination	Diagnosis
		Age of onset	Muscle weakness	Fever	Myalgia	Contractures	Gait abnormality	Neuropathy	Atrophy	Stiffness	Myoglobinuria	Other features	Laboratory Findings			Creatine Kinase	Muscle Biopsy	Electromyogram
Medication−induced	Alcohol	Variable	Proximal	−	−	−	+	+/−	−	−	−	Swelling Tender Erythema and induration	Alcohol intoxication	Change in mental status Telangiectasia Peripheral neuropathy	Monspecific and are normal in many patients	Normal or ↑↑	Normal	Normal
Endocrine	Diabetic infraction	45	Proximal	+	+	−	−	+	+	−	−	Cramps Sudden onset of pain Anterior thigh muscles are most commonly involved	H/O long standing diabetes	Swelling Tenderness	Elevated ESR Leukocytosis	Normal	Necrosis Edema	Normal
Inflammatory/ Rheumatologic	Fibromyalgia	40−50s	Generalized	−	−	−	−	+	−	−	−	Anxiety or depression features Fatigue Sleep disturbance Numbness Muscle spasms	History of depression	Tenderness in the soft tissue anatomical location	Normal	Normal	Normal	Normal
Organ system	Disease	Age of onset	Muscle weakness	Fever	Myalgia	Contractures	Gait abnormality	Neuropathy	Atrophy	Stiffness	Myoglobinuria	Other features	History	Physical Examination	Laboratory Findings	Creatine Kinase	Muscle Biopsy	Electromyogram
Infectious	Lyme disease	Variable	Proximal	+	+	−	+/−	+	−	−	−	Erythema Migrans Flu−like symptoms Lyme arthritis Neurological manifestations	H/o tick bite Hiking trip	Target−like lesions HSM	Clinical diagnosis +Serology	N/A	N/A	N/A
	Polio	<5 yrs	Proximal	−	−	−	+	+	+	−	−	Asymmetrical paralysis Muscle atrophy Tremors Skeletal deformities	History of skipped immunization.	Normal Meningeal signs Asymmetrical flaccid paralysis Pharyngeal paralysis	Isolation from pharyngealsecretions, CSF Positive serology	N/A	N/A	Neurological pattern
	Syphilis	Variable	Negative	−	−	−	+	+	−	−	−	Chancre Lymphadenopathy Condylomata lata Neuro syphilis Cardiovascular syphilis	History of risk factors (MSM, unprotected sex, multiple sex partners)	Non−tender chancre in primary syphilis. Followed by rash Generalized lymphadenopathy in secondary syphilis	Darkfield examinations VDRL RPR FTA−ABS	N/A	N/A	N/A
Organ system	Disease	Age of onset	Muscle weakness	Fever	Myalgia	Contractures	Gait abnormality	Neuropathy	Atrophy	Stiffness	Myoglobinuria	Other features	History	Physical Examination	Laboratory Findings	Creatine Kinase	Muscle Biopsy	Electromyogram
Neurologic	ALS	>35	Proximal & Distal Distal	−	−	−	−	+	+	+	−	Dysphagia Spasticity Hyperreflexia Babinski's +	N/A	Both upper and lower motor neuron signs	Clinical diagnosis	Normal	Nonspecific findings of chronic denervation with reinnervation	Neuropathic
	Stroke	>65	Proximal & distal	−	−	−	+	+	+	−	−	Dysphagia Unilateral/Bilateral weakness	H/o HTN, dyslipidaemia DM	Weakness of the involved arm	Head CT	Normal	Normal	Neuropathic
	Multiple Sclerosis	30's	Proximal & distal	−	−	−	+	+	−	−	−	Ocular findings Urinary incontinence Problems with speech or swallowing	Attacks or exacerbation	Localized weakness Focal sensory disturbances Hyper reactive reflexes Increased tone or stiffness	Head CT ologo−clonal bands	Normal	N/A	Neuropathic