Table 4.

Laboratory, electrophysiologic, radiographic, and clinical findings of MG in myositis-MG patients.

Patient	AChR Ab	MuSK Ab	SFEMG	RNS	Thymic hyperplasia*	Pyridostigmine response#	Worse with steroids
1	+	Not done	Not done	Abnl	−	+	+
2	−	-	Abnl	Normal	+	+	−
3	+	Not done	Abnl	Not done	−	−	−
4	−	-	Normal	Abnl	+	+	+
5	+	-	Not done	Abnl	−	+	−
6	+	Not done	Not done	Abnl	−	+	−

Ab = antibody, Abnl =abnormal, “−” = negative or symptom not reported, “+” = positive or symptom present

^*determined by chest CT scan.

^#defined as an immediate (within hours of administration) but transient improvement with pyridostigmine.