Hypothyroidism presenting as tendinitis.

Area of Science:

• Endocrinology
• Sports Medicine
• Rheumatology

Background:

• Hypothyroidism often presents with subtle symptoms like fatigue and weight gain.
• Less common symptoms include myalgia, arthralgia, and joint effusions, which can be mistaken for other conditions.
• Overuse syndromes in athletes are frequently diagnosed, potentially masking underlying systemic issues.

Purpose of the Study:

• To highlight the importance of considering hypothyroidism in the differential diagnosis of athletes presenting with symptoms suggestive of overuse injuries.
• To emphasize the diagnostic challenges posed by the insidious onset of hypothyroidism.
• To underscore the benefits of timely diagnosis and thyroid hormone replacement therapy.

Main Methods:

• Case report of a triathlete with persistent symptoms initially misdiagnosed as tendinitis.
• Review of clinical presentation and diagnostic pathways for hypothyroidism.
• Discussion of diagnostic criteria and treatment protocols for hypothyroidism.

Main Results:

• The patient's symptoms of fatigue, myalgia, and joint pain were initially attributed to tendinitis, leading to treatment failure.
• Delayed diagnosis of hypothyroidism occurred due to the atypical presentation mimicking overuse syndrome.
• Thyroid hormone level testing confirmed hypothyroidism, and subsequent hormone replacement led to symptom resolution.

Conclusions:

• Hypothyroidism should be included in the differential diagnosis for athletes experiencing persistent or unexplained musculoskeletal symptoms.
• Misinterpretation of hypothyroidism symptoms as overuse injuries can lead to significant treatment delays.
• Prompt diagnosis via thyroid hormone level testing and appropriate thyroid hormone replacement are effective.