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Health Dictionary

Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.

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Muscle weakness and Fever

Introduction

Differential Diagnosis of Muscle Weakness and Fever

Differential Diagnosis of Muscle Weakness and Fever

Organ system Disease Symptoms History Physical

Examination

Diagnosis
Age of onset Muscle weakness Fever Myalgia Contractures Gait abnormality Neuropathy Atrophy Stiffness Myoglobinuria Other features Laboratory Findings Creatine Kinase Muscle Biopsy Electromyogram
Endocrine Diabetic infraction[1] 45  Proximal + + − − + + − −
  • Normal
  • Normal
Inflammatory/ Rheumatologic Dermatomyositis[2] 40s−50s
Can affect children 		Proximal + + − − − − + −
  • ↑↑
  • Perimysial mononuclear infiltrate
Polymyositis[3] > 18 years Proximal + + − − − − + −
  • N/A
  • N/A
  • ↑↑
  • Endomysial mononuclear infiltrate
  • Patchy necrosis
Polymyalgia Rheumatica[4] 50s Diffuse + + − − − − + −
  • History of joints stiffness, worse in the morning
  • Restricted shoulder motion
  • Normal
  • Normal
  • Normal
Organ system Disease Age of onset Muscle weakness Fever Myalgia Contractures Gait abnormality Neuropathy Atrophy Stiffness Myoglobinuria Other features History Physical

Examination

Laboratory Findings Creatine Kinase Muscle Biopsy Electromyogram
Infectious Lyme disease[5] Variable Proximal + + − +/− + − − −
  • H/o tick bite
  • Hiking trip
  • Clinical diagnosis
  • +Serology
  • N/A
  • N/A
  • N/A
Influenza[6] Variable Proximal and Distal + + − + − − − +
  • Cold weather
  • H/o Ill contacts
  • Muscle weakness, tenderness, and swelling.
  • ↑↑ Liver enzymes
  • Positive PCR
  • ↑↑
  • N/A
  • N/A
Pyomyositis[7] Variable Proximal
&
Distal 		+ + − − − − + −
    • Muscles are painful, swollen, tender, and indurated.
    • Depending on the site of involvement, it may mimic appendicitis (psoas muscle), septic arthritis of the hip (iliacus muscle), or epidural abscess (piriformis muscle).
  • Leukocytosis
  • Elevated ESR
  • N/A
  • N/A
  • N/A
References

References

  1. ↑ Horton WB, Taylor JS, Ragland TJ, Subauste AR (2015). “Diabetic muscle infarction: a systematic review”. BMJ Open Diabetes Res Care. 3 (1): e000082. doi:10.1136/bmjdrc-2015-000082. PMC 4410119. PMID 25932331.
  2. ↑ Dalakas MC (1991). “Polymyositis, dermatomyositis and inclusion-body myositis”. N Engl J Med. 325 (21): 1487–98. doi:10.1056/NEJM199111213252107. PMID 1658649.
  3. ↑ Dalakas MC (1991). “Polymyositis, dermatomyositis and inclusion-body myositis”. N Engl J Med. 325 (21): 1487–98. doi:10.1056/NEJM199111213252107. PMID 1658649.
  4. ↑ Myklebust G, Gran JT (1996). “A prospective study of 287 patients with polymyalgia rheumatica and temporal arteritis: clinical and laboratory manifestations at onset of disease and at the time of diagnosis”. Br J Rheumatol. 35 (11): 1161–8. PMID 8948307.
  5. ↑ Schoenen J, Sianard-Gainko J, Carpentier M, Reznik M (August 1989). “Myositis during Borrelia burgdorferi infection (Lyme disease)”. J. Neurol. Neurosurg. Psychiatry. 52 (8): 1002–5. PMC 1031843. PMID 2795056.
  6. ↑ Bove KE, Hilton PK, Partin J, Farrell MK (1983). “Morphology of acute myopathy associated with influenza B infection”. Pediatr Pathol. 1 (1): 51–66. PMID 6687269.
  7. ↑ Crum NF (September 2004). “Bacterial pyomyositis in the United States”. Am. J. Med. 117 (6): 420–8. doi:10.1016/j.amjmed.2004.03.031. PMID 15380499.

Editor-In-Chief:
C. Michael Gibson, M.S., M.D. [1]