A 44-year-old woman presented with worsening low back pain of 1 month’s duration. She also complained of difficulty chewing and blurred vision for 1 week and diffuse weakness in the lower extremities. She denied headaches, vertigo, or other neurologic symptoms. Her medical history was remarkable for insulin-dependent diabetes for over 6 years. She did not smoke, drink alcohol, or use recreational drugs.
General physical examination was unremarkable. Neurologic examination revealed mild bilateral peripheral facial weakness and bilateral external rectus muscle weakness; other cranial nerves were normal ( Fig. 30-1 ). She had 4/5 strength with tenderness to palpation in the proximal muscles of the lower extremities and back. Distal leg muscles were 5−/5. Reflexes were absent throughout. Vibration sense was absent in the ankles and decreased at the knees. Pain and touch sensation was decreased up to the ankles. The rest of the examination was unremarkable.
What is the Differential Diagnoses?
This diabetic patient developed bilateral VI and VII nerve palsies and had a polyneuropathy. The combination of findings can be present in central nervous system disorders such as multiple sclerosis. However, there was no evidence of long tract signs or other findings to suggest a central lesion, and the presentation appeared to involve only peripheral nerves. The findings on examination could suggest a diabetic polyneuropathy with cranial neuropathies. Other possibilities include vasculitic neuropathy from connective tissue disorders such as Sjögren’s and lupus, but there was no evidence of asymmetric neuropathy in the limbs or other manifestations of those disorders. Leprosy could present with bilateral facial neuropathy but characteristically not with VI nerve palsies. Lyme disease could also cause facial palsy and other cranial neuropathies.
Tuberculosis and sarcoidosis can manifest with basilar meningitis and cranial nerve palsies, and those should be included in the differential diagnosis. She also complained of back pain; this could be related to a lumbar disk disease as her other neurologic problems were caused by an inflammatory process in the lumbosacral nerves or roots. Another consideration is a nervous system lymphomatosis.
An EMG Test was Performed
Motor Nerve Studies
|
|
Ankle |
5.4 |
2 |
– |
Fibular head |
13.6 |
2 |
37 |
Knee |
16.6 |
1 |
33 |
|
|
Ankle |
5.2 |
4 |
– |
Pop. fossa |
15.1 |
3 |
39 |
|
|
Wrist |
8.1 |
6 |
– |
Elbow |
13.2 |
6 |
43 |
|
Wrist |
3.8 |
13 |
– |
Below elbow |
7.8 |
13 |
53 |
|
Wrist |
5.5 |
15 |
– |
Elbow |
9.9 |
15 |
50 |
|
|
Facial nerve R. |
4.85 |
2.5 |
– |
Facial nerve L. |
4.45 |
2.7 |
– |
F-Wave and Tibial H-Reflex Studies
|
Peroneal nerve R. |
58.8 |
54 |
Tibial nerve L. |
61 |
54 |
Median nerve R. |
36.8 |
30 |
Ulnar nerve R. |
29.6 |
30 |
Median nerve L. |
31 |
30 |
H-reflex R. |
NR |
34 |
H-reflex L. |
NR |
34 |
