Rojas ZA, Garrido ME, Nishimura ME

Language: Spanish
References: 9
Page: 66-70
PDF size: 99.70 Kb.

ABSTRACT

Antecedents: The treatment of congenital hypothyroidism (CH) is daily administration of levothyroxine (L-T₄) according to clinical and biochemical goals. The preparation available at our institution is limited to 100 µg tablets of levothyroxine and allows changes in fractions of 25 µg. In case of not achieving the treatment goals with levothyroxine distributed in Daily Equitable Dosage (DED), it is common practice to prescribe different daily doses, Daily Non Equitable Doses (DNED), with weekly dosage providing an appropriate average/day dosage. Objective: To investigate the efficacy of these two treatment plans in children with CH diagnosed after neonatal screening. Design and setting: 36 cases between 1-5 years old with CH were included. All of them were initially treated with DED and reassigned to DNED according to free T4, total T4 and TSH levels. Results: No difference was found in age, height, weight/height and severity of the hypothyroidism at diagnosis between patients treated with DED (18 cases) or DNED (18 cases). DNED-treated children had higher frequency of normothyroxinemia (free and total T4 levels in the upper half of the normal range, 94.4% vs 77.8%), lower frequency of TSH levels 4-10 mUI/mL as an isolated finding in the prior 6 months (27.8% vs 33.3%) and lower inadequate substitution (5.6% vs 22.2%), but this lacked statistical significance. Conclusions: The data of our study provide evidence that Daily Non Equitable Dose was effective in patients with CH whom the Daily Equitable Dose didn’t result in biochemical goals. Even so, lower milligram tabs allows more precise dosaging and better compliance and minimizes the possibility of mistake.

REFERENCES

1. Boletín Semanal de Vigilancia Epidemiológica. Instituto Mexicano del Seguro Social 2007.

2. Connelly JF, Coakley J, Gold H, Francis I, Mathur KS, Rickards AL et al. Newborn screening for congenital hypothyroidism, Victoria, Australia, 1977-1997. Part 1: The Screening Programme, Demography, Baseline Perinatal Data and Diagnostic Classification 2001; 14: 1597-1610.

3. Grant DB. Management of hypothyroidism. Current Paediatrics 1997; 7: 92-97.

4. Fisher DA. Management of congenital hypothyroidism. J Clin Endocrinol Metab 1991; 72: 523-529.

5. Ruiz MA, Morales ME, Atienza M. Estabilidad de levotiroxina en fórmula magistral de uso en pediatría. Rev OFIL 2005; 15: 47-54.

6. Instituto Mexicano del Seguro Social. Cuadro Básico Institucional de Medicamentos 2007.

7. Salerno M, Militerni R, Bravaccio C, Micillo M, Capalbo D, Salvatore DM. Effect of different starting doses of levothyroxine on growth and intellectual outcome at four years of age in congenital hypothyroidism. Thyroid 2002; 12: 45-52.

8. Grebe S, Cooke R, Ford H et al. Treatment of hypothyroidism with once weekly thyroxine. J Clin Endocrinol Metab 1997; 82: 870-875.

9. Scott A, Rivkees MD, Dana S. Cretinism after weekly dosing with levothyroxine for treatment of congenital hypothyroidism. J Pediatr 1994; 125: 147-149.