Switch from tablet levothyroxine to oral solution resolved reduced absorption by intestinal parasitosis

Reduced intestinal absorption of levothyroxine (LT4) is the most common cause of failure to achieve an adequate therapeutic target in hypothyroid patients under replacement therapy. We present the case of a 63-year-old woman with autoimmune hypothyroidism previously well-replaced with tablet LT4 who became unexpectedly no more euthyroid. At presentation, the patient reported the onset of acute gastrointestinal symptoms characterized by nausea, loss of appetite, flatulence, abdominal cramps and diarrhea, associated with increase of thyrotropin levels (TSH: 11 mIU/mL). Suspecting a malabsorption disease, a thyroxine solid-to-liquid formulation switch, at the same daily dose, was adopted to reach an optimal therapeutic target despite the gastrointestinal symptoms persistence. Oral LT4 solution normalized thyroid hormones. Further investigations diagnosed giardiasis, and antibiotic therapy was prescribed. This case report is compatible with a malabsorption syndrome caused by an intestinal parasite (Giardia lamblia). The reduced absorption of levothyroxine was resolved by LT4 oral solution. Learning points: The failure to adequately control hypothyroidism with oral levothyroxine is a common clinical problem. Before increasing levothyroxine dose in a patient with hypothyroidism previously well-controlled with LT4 tablets but no more in appropriate therapeutic target, we suggest to investigate non adhesion to LT4 therapy, drug or food interference with levothyroxine absorption, intestinal infection, inflammatory intestinal disease, celiac disease, lactose intolerance, short bowel syndrome after intestinal or bariatric surgery, hepatic cirrhosis and congestive heart failure. LT4 oral solution has a better absorptive profile than the tablet. In hypothyroid patients affected by malabsorption syndrome, switch of replacement therapy from tablet to liquid LT4 should be tested before increasing the dose of LT4.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:2019

Enthalten in:

Endocrinology, diabetes & metabolism case reports - 2019(2019) vom: 21. März

Sprache:

Englisch

Beteiligte Personen:

Tortora, Anna [VerfasserIn]
La Sala, Domenico [VerfasserIn]
Vitale, Mario [VerfasserIn]

Links:

Volltext

Themen:

2019
Abdominal cramp
Adult
Antibiotics
Appetite reduction/loss
BMI
Diarrhoea
FT3
FT4
Female
Flatulence
Hypoalbuminaemia
Hypothyroidism
Italy
Journal Article
Levothyroxine
March
Nausea
Novel treatment
TSH
Thyroid
Thyroid antibodies
Thyroid function
Thyroid ultrasonography
Thyroiditis
Thyroxine (T4)
Triiodothyronine (T3)
Ultrasound scan
Weight
Weight loss
White

Anmerkungen:

Date Revised 27.02.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1530/EDM-19-0026

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM295201746