Real-time PCR using FRET technology for Old World cutaneous leishmaniasis species differentiation

Abstract

Feline hyperthyroidism is currently treated with anti-thyroid drugs, surgery and/or radiotherapy. Recently, an iodine-deficient diet (Hill's® Prescription diet® y/d®: “y/d”) emerged as an alternative treatment, but limited data are available on therapeutic effects on a large cohort. Sixty-six cats were retrospectively included, based on a diagnosis of hyperthyroidism (clinical signs and free thyroxinemia “fT4” >40 pmol/L). All received the iodine-deficient diet as a first-line treatment and as exclusive food. We aimed to assess the clinical and biological efficiencies of this diet. Forty-seven females (41 spayed) and 19 males (16 neutered), mainly Domestic Short Hair (88%) and ranged from 8 to 20 years (median 13.6 years), were retrospectively included in the study. The main clinical signs at diagnosis were weight loss (94%), polyuropolydipsia (74%), polyphagia (67%), tachycardia (56%), digestive signs (54%) and palpable thyroid nodule (31%). The main biological signs were high fT4 (median: 68 pmol/L, range [40;100]), uremia >3.6 mmol/L for 46% of the cats, creatininemia >159 μmol/L for 11% and ALT >80 U/L for 62%. 54.3% of the cats received dry y/d, 5.7% the canned form and 40.0% both. The majority of the cats (90%) accepted to eat y/d but only 1/3 accepted it spontaneously in a first place. At the first control (median time = 64 days), the clinical efficiency was considered by the practioners as satisfactory for 40% of the cats, partial for 40%, and poor for 20%. Body weight was not significantly changed after y/d (3.6 kg [1.8–5.8] versus 3.3 kg [2.0–5.9]; P = 0.82). fT4 significantly decreased (68 pmol/L before y/d and 39 pmol/L after y/d, P < 0.001) with 47.8% of the cats having a fT4 < 35 pmol/L after treatment. No significant change was observed concerning uremia (6.6 mmol/L [1.2–10.8] before y/d and 3.0 mmol/L [1.2–6.5] after y/d; P = 0.20), creatininemia (81.4 μmol/L [23.0–212.4] before y/d and 77.9 μmol/L [20.4–179.7]after y/d; P = 0.17) and ALT activity (107 U/L [18–758] before y/d and 90 U/L [10–800] after y/d; P = 0.90) after treatment. The iodine-deficient diet Hill's® y/d® was associated with a satisfactory clinical improvement in 40% of the cats and a significant decrease in fT4 two months after the beginning of the treatment. A long-term follow-up study is currently conduced to assess y/d palatability, clinical and biological changes (particularly creatininemia and ALT activity) and survival on this cohort.