American Journal of Medical Case Reports
ISSN (Print): 2374-2151 ISSN (Online): 2374-216X Website: Editor-in-chief: Samy, I. McFarlane
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American Journal of Medical Case Reports. 2014, 2(11), 253-255
DOI: 10.12691/ajmcr-2-11-8
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Clinical Application of the Levothyroxine Absorption Test in the Diagnosis of Pseudo-Malabsorption

Muhammad Imran Butt1, Nidhi Gupta1, Hiang Leng Tan2, and Najeeb Waheed3

1Department of Diabetes and Endocrinology, Peterborough City Hospital, Peterborough, UK

2Department of Diabetes and Endocrinology, Weston General Hospital, Weston-super-Mare, UK

3Department of Diabetes and Endocrinology, Hereford County Hospital, Hereford, UK

Pub. Date: November 11, 2014

Cite this paper:
Muhammad Imran Butt, Nidhi Gupta, Hiang Leng Tan and Najeeb Waheed. Clinical Application of the Levothyroxine Absorption Test in the Diagnosis of Pseudo-Malabsorption. American Journal of Medical Case Reports. 2014; 2(11):253-255. doi: 10.12691/ajmcr-2-11-8


We present a variation and clinical application of the Levothyroxine Absorption Test (LAT) in the identification of pseudo-malabsorption of levothyroxine in uncontrolled hypothyroidism, for which there is no current gold standard protocol, and a variety of methods proposed in the literature. The LAT was conducted over 5-days with thyroid function tests conducted pre-LAT, then at day 1 and 5. The thyroid stimulating hormone levels became completely suppressed indicating that there had been previous non-compliance with medication.

levothyroxine absorption test non-compliance pseudo-malabsorption

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