Chief complaint: Weakness

HPI: A 7 year 11 month old boy presents for evaluation of progressive weakness.

The patien has had recurrent strep throats since childhood and since age 6 yo, recurrent canker sores. About 6 months prior to presentation, he had a fever and sore throat for about 7-10 days and weight loss from 48 to 45 pounds. He was treated with antibiotics for possible strep throat.

Since then, he has become weak and his limbs have become thin. He had increasing trouble climbing stairs; he now climbs one step at a time and at the top of the flight of stairs and puts his arm on his knee for support. He has difficulty rolling over in bed, getting into bed, lifting his backpack, and raising arms overhead. He was treated with cyproheptadine to gain weight and he has regained 3 pounds to baseline 48 lbs.

His birth and development were normal. He walked at 9 months and talked at 12 months. He was able to run and ride a bike well. In pre-school, he had behavioral issues attributed to ADHD and sensory processing disorder. A physical therapist noted decreased core strength. He was athletic and, at age 4 years, he was able to jog nearly one mile with his father. He was thin with height at ~50 percentile. According to growth chart, BMI was 25th percentile at 5 years old. Photographs show increasing body thinness after age 3. He and his parents denied muscle pain, muscle tenderness or rash. He has no family history of myopathy. Both of his parents are doctors and he was raised in NYC.

Exam:

General: thin-appearing, BMI <5th percentile for age

~5mm circular erythematous papule and ~5mm hypopigmented macule on forehead. GroupHeading55End GroupHeading74Start GroupHeading74End GroupHeading106Start

HEENT: normocephalic, high arched palate. GroupHeading5End GroupHeading18Start

Pulmonary: Counted to 20 on one breath

All other general exam features were normal.GroupHeading19End GroupHeading22Start GroupHeading22End GroupHeading108Start GroupHeading108End GroupHeading23Start

GroupHeading47End GroupHeading49Start GroupHeading49End GroupHeading50Start GroupHeading50End GroupHeading109Start GroupHeading109End GeneralMulti-SystemExamCopyneuropedsmdasmab8be37e7-f9d8-46b5-8d75-761244de81c1FormEnd NeuroPediatricExamCopy3c15e4f6-463e-4db1-92e9-ea291bcd1118FormStart

GroupHeading338Start GroupHeading338End GroupHeading312Start GroupHeading312End GroupHeading111Start Mental Status: Normal

Cranial nerve exam: Notable for bilateral facial weakness with linear smile and weak orbiculari oculi and 4/5 sternocleidomastoid strength.

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MOTOR EXAMINATION:.

Appearance: Atrophy of upper arms, paraspinals. Scapular winging with arms stretched forward.

Tone: Normal.

Strength: Neck flexion 2 / 5, Neck extension 4 / 5

Both arms: Shoulder abduction 2 / 5,Elbow flexion 4 / 5,Elbow extension 4 / 5,Wrist flexion 5 /5,Wrist extension 4 / 5,Fingers flexion 5 / 5,

Both legs: 4/5 bilaterally, symmetrically in proximal muscles and normal distal strength.

GroupHeading151End GroupHeading316Start GroupHeading316End GroupHeading241Start GroupHeading241End GroupHeading242Start GroupHeading242End GroupHeading348Start GroupHeading348End GroupHeading347Start GroupHeading347End GroupHeading343Start GroupHeading343End GroupHeading344Start GroupHeading344End GroupHeading345Start GroupHeading345End GroupHeading346Start GroupHeading346End GroupHeading247Start

Sensation normal to light touch, pinprick, temperature, vibration and propioceptionGroupHeading247End GroupHeading86Start GroupHeading86End GroupHeading87Start GroupHeading87End GroupHeading83Start GroupHeading83End GroupHeading317Start GroupHeading317End GroupHeading229Start

Reflexes 2+ throughoutGroupHeading229End GroupHeading230Start GroupHeading230End GroupHeading232Start GroupHeading232End GroupHeading3Start GroupHeading3End GroupHeading2Start GroupHeading2End GroupHeading5Start GroupHeading5End GroupHeading231Start GroupHeading231End GroupHeading6Start GroupHeading6End GroupHeading337Start GroupHeading337End GroupHeading339Start GroupHeading339End GroupHeading340Start GroupHeading340End GroupHeading245Start , toes downgoing

Coordination: Normal. GroupHeading328End FreeTextEntry149Start FreeTextEntry149End GroupHeading329Start

Gait: GroupHeading329End FreeTextEntry150Start Lordotic posture, decreased arm swing. FreeTextEntry150End GroupHeading330Start GroupHeading330End FreeTextEntry151Start FreeTextEntry151End GroupHeading334Start GroupHeading334End FreeTextEntry152Start Gowers sign.

FreeTextEntry152End NeuroPediatricExamCopy3c15e4f6-463e-4db1-92e9-ea291bcd1118FormEnd

Discussion of differential diagnosis of myopathy:

  • Inflammatory
  • Polymyositis, dermatomyositis, inclusion body myositis
  • Infectious
  • HIV, Lyme, S. Aureus, etc.
  • Toxic
  • Steroids, alcohol, amiodarone, etc.
  • Associated with systemic disease
  • Critical illness, metabolic disturbance, thyroid
  • Hereditary
  • Dystrophies, metabolic, mitochondrial, etc.

Labs:

CK was 8399 (normal <177),

AST 176 (normal 12-32), ALT 215 (normal 8-30).

EBV EBNA IgG 233 (normal <18), EBV VCA IgG 177 (normal <18).

The following were normal or negative CBC, BMP, TSH, celiac serology, Hep B core Ab, surface Ag, Hep C, EBV VCA igM, ESR, CRP, and cortisol.

EMG:

Myopathic Motor Unit Potentials and 1+ spontaneous activity in left tibilais anterior and vastus lateralis, but not other muscles; these results are consistent with myopathy.

Muscle biopsy (Dr. Tanji)

(Blood test showed +Anti-SRP antibody)