We present the case of an 80-year old female with weight loss secondary to Graves' thyrotoxicosis. This patient had chronic anxiety, increasing myopathic symptoms which impacted on her Irish dancing and mild bilateral orbitopathy. On further history she has a 13 year history of chronic lymphocytic leukaemia (CLL) not requiring treatment to date. This is on a background of post-menopausal osteoporosis without fractures. Progressive bone loss was seen despite treatment with zoledronic acid and calcium/vitamin D supplementation, likely contributed to by a degree of hyperthyroidism. Chronic lymphocytic leukaemia (CLL) is well known to be associated with autoimmune phenomena. These are most frequently related to the haematopoietic system but other autoimmune disorders, including rheumatoid arthritis, pernicious anaemia, myasthenia gravis and Graves’ disease have also been reported in patients with CLL [1]. In this case discordance is seen between the high TRAb levels and the near normal thyroid function tests suggesting the presence of TSH receptor blockade (Table 1.). This case highlights the need to be mindful of antibodies beyond the TRAb when considering autoimmune thyroid dysfunction, in this case, possibly associated with an underlying B-cell leukaemia.
|
Date |
February 2020 |
June 2020 |
September 2020 |
March 2021 |
August 2021 |
|
TSH mIU/L (0.4-5.0) |
5.94 |
2.07 |
0.19 |
3.64 |
0.39 |
|
fT4 pmol/L (10-20) |
11.0 |
12.8 |
18.4 |
14.3 |
15.9 |
|
fT3 pmol/L (2.3-5.7) |
4.8 |
3.5 |
4.3 |
4.4 |
5.1 |
|
TRAb IU/L (<2.1) |
59.3 |
77.2 |
43.2 |
49.1 |
48.8 |