Page 797 - Clinical Immunology_ Principles and Practice ( PDFDrive )

CHaPtEr 56 Inflammatory Muscle Diseases 767.e1

MUL t IPLE-CHOICE QUES t IONS

1. A 42-year-old Asian woman comes to your office complaining about 1 year later. He also began having difficulties walking
of a rash on her face and upper back that started 2 months on uneven ground. He has not had any difficulty swallowing.
ago. Around the same time, she developed joint pain and His past medical history is significant for elevated serum CK
swelling in both hands. Approximately a week ago, she noticed levels of 1400 (normal range: 24–170 U/L) 5 years ago and
mouth sores as well as weakness, with difficulties walking hypercholesterolemia. His family history includes breast cancer
upstairs. Other medical problems include an episode of in his mother. He has a 33-pack-year smoking history,
pulmonary collapse resulting in intensive care unit admission but he quit 2 years ago. He has no other medical problems.
and requiring intubation and treatment with antibiotics and Neurological examination reveals reduced triceps strength
steroids 3 years ago, but she had full recovery after this. (right: 4+/5, left: 4/5), finger flexion (2/5 bilaterally), knee
Otherwise, she has been healthy. She has never smoked and extension (4+/5 bilaterally), and left wrist flexion (4+/5) muscle
does not drink alcohol. Her mother has rheumatoid arthritis. strength. The patient’s laboratory tests show an elevated CK
She takes no medications. Physical examination reveals level of 1030 U/L. Electromyography reveals positive waves,
heliotrope rash, Gottron sign, shawl sign, nail bed erythema, fibrillations, and mixed neurogenic and myopathic motor
dilated capillary loops, and swelling of the hands. There is units in the involved muscles. A quadriceps muscle biopsy is
extensive ulceration and necrosis of the fourth digit. Neurologi- performed. Which of the following findings is most likely
cal examination demonstrates symmetrically reduced hip present on biopsy?
flexion (4/5) muscle strength. Further evaluation reveals a A. Many necrotic muscle fibers and sparse inflammatory cells
serum CK level of 100 U/L (normal range: 24–170 U/L) and B. Perifascicular atrophy
an aldolase level of 15.6 U/L (normal = <8.1 U/L). Which of C. Endomysial inflammatory infiltrate and rimmed vacuoles
the following antibodies is most likely to be detected in this D. MAC depositions on small blood vessels
patient’s serum? 3. Which of the following antibodies is associated with the disease
A. Anti-Jo-1 presented in question 2?
B. Anti-SRP A. Anti-HMGCR
C. Anti-RNP B. Anti-SAE
D. Anti-MDA5 C. Anti-c5N1A
E. Anti-La
D. Anti-Mi-2
2. A 58-year-old Caucasian man began noticing progressive E. Anti-SRP
weakness with bilateral foot slapping 3 years ago. He began F. No recognized antibodies are associated with this
struggling with stairs and progressive weakness in his handgrip condition.