Case presentation:
A 34-year-old woman with no
medical history presented to our department with a five-day history of
arthritis affecting the small joints of the left hand, wrist, right
elbow, and ankle. She had myalgia without sicca symptoms.
Physical examination showed a normal blood pressure of 110/60 mmHg,
synovitis of the left wrist and metacarpophalangeal joints, right elbow,
and ankle.
Laboratory findings revealed a high C-reactive protein level (28 mg/L,
Normal value (N) < 6), normocytic anemia (hemoglobin: 7.7
g/dL, N ≥ 12 g/dL, mean corpuscular volume: 96.5 femtoliter, N: 80 –
100), high Lactate dehydrogenase (LDH) level (280 IU/L, N: 91 – 260),
and high Creatine-phosphokinase (CPK) level (485 IU/L, N: 22 – 269).
Liver and renal tests were within the normal range.
Anti-nuclear antibodies (ANA), anti-SSA, SSB, rheumatoid factor, and
anti-citrullinated protein antibodies (ACPA) were negative.
C3 and C4 complement levels were normal. Thyroxine (T4) level was low
(2.8 pmol/L, N: 7.9 – 14.4), and thyroid-stimulating hormone (TSH)
level was high (39 µIU/L, N: 0.34 – 5.6). The thyroid peroxidase
antibodies were positive (670 IU/mL, N: <35 IU/mL), whereas
anti-thyroglobulin antibodies were negative.
Radiographs of hands, feet, and pelvic were without abnormalities.
Musculoskeletal ultrasound showed synovial thickening of the left wrist
and the right elbow with hyperemia in power Doppler imaging. There was
also synovial thickening of the left metacarpophalangeal joints, right
ankle, and tenosynovitis of the posterior tibial and
fibular tendons. The chest radiograph was normal. Thyroid ultrasound
showed inhomogeneous and hypoechogenic thyroid parenchyma. However,
ultrasonography of the salivary glands was without abnormalities.
The diagnosis of primary hypothyroidism related to Hashimoto thyroiditis
was made. There were not enough criteria to make the diagnosis of
Sjogren’s syndrome.
A thyroid hormone replacement therapy was started at 25µg daily and
increased progressively to reach 150 µg daily.
After three months of treatment, the TSH level had become within the
normal range, and polyarthritis had disappeared. The TSH level remained
stable, and the patient didn’t develop a recurrence of the polyarthritis
after 20 months of follow-up.
Consent from the patient for publication of this case study was
obtained.