CASE

A 79 year old woman, a heterozygote for factor V Leiden, had diffuse weakness. It started in the summer of 2013. She was admitted in September for proximal weakness of her upper and lower extremities. She had difficulty holding her head up. She used ski poles to walk. She had fallen. She was dyspneic.

She had had pulmonary emboli. She takes warfarin.

In the hospital, she had a CTA to rule out recurrent emboli as the cause of her dyspnea. Troponins were slightly elevated. A cardiology consultant found no cardiologic cause for her weakness. CK was normal. Anti-smooth muscle antibodies were neg. She had a Klebsiella UTI, and received antibiotics. She was discharged.

On December 4, she went to the POMH ER because she could not swallow water. Physicians ordered an antiAChR antibody and sent her to the MMC ER, where she was admitted that evening. Her magnesium was low at 1.4.

The medical student on her case called for a Neurology consult on December 5th. He said she had diffuse weakness and was somewhat dyspneic. They thought she had myasthenia gravis. He said an anti-AchR antibody test had been ordered, but results were pending.

The NIF returned at -10. She was transferred to the ICU, under the care of the hospitalists. Her ABGs, on 3 L, were pH 7.26, pCO2 56, pO2 136. She was put on a non-rebreather.

Pharmacy Help

AChR BINDING AB: 50.5

MuSK Antibody Titer: <10_____________________________________

ACh RECEPTOR MODULATING Ab: 81 0-20% (reported as _% loss of AChR)

STRIATIONAL (STRIATED MUSCLE) : Positive 1:15360

Reference range: <1:60

AChR BINDING AB: 39.6 Reference range: <=0.02