ABSTRACT
Thiamine responsive megaloblastic anemia syndrome is a rare autosomal recessive disease caused by mutations of the SLC19A2 gene that encodes the high-affinity thiamine transporter-1.Thiamine responsive megaloblastic anemia syndrome involves extensive organs and systems with various clinical manifestations.The typical triad is megaloblastic anemia, non-autoimmune diabetes, and sensorineural deafness.The diagnosis of thiamine responsive megaloblastic anemia syndrome depends on the detection of the pathogenic gene SLC19A2.Thiamine replacement therapy is the first-line treatment.Blood glucose of patients with thiamine responsive megaloblastic anemia syndrome should be comprehensively managed, and hearing aids and cochlear implants can be used to improve the hearing.
ABSTRACT
OBJECTIVE@#To assess the efficacy of letrozole in treatment of children with congenital adrenal hyperplasia (CAH) due to steroid 21-hydroxylase deficiency (21-OHD).@*METHODS@#Twenty eight children, including 19 boys and 9 girls aged 4-10y, with CAH due to 21-OHD were enrolled in the study. At the first six months of study, all children received conventional treatment with hydrocortisone or fludrocortisone, then letrozole was added to original regimen. The height velocity (HV), difference between bone age and chronological age (BA-CA), height standard diviation score based on bone age (HtSDS ), predicted adult height (PAH), Tanner phase, sex hormone, and possible adverse reaction were evaluated and compared between those before and after letrozole treatment.@*RESULTS@#After 6 months of letrozole treatment, there was significant deceleration of HV, but it would recover soon. There was significant increase of HtSDS after 12 months of letrozole treatment ( < 0.05 or < 0.01), and significant changes in BA-CA after 18 months of letrozole treatment ( < 0.05). PAH of female children was significantly increased during letrozole treatment ( < 0.05), whereas PAH of male children was significantly increased 18 months after letrozole treatment ( < 0.05). Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were significantly increased, but did not meet the diagnostic criteria of central precocious puberty. Estradiol was significantly decreased ( < 0.01), but no changes in testosterone level was observed. During 24 months letrozole treatment, no hirsutism, severe acne, headache, bone pain, obesity, hypertension, rash and other adverse reactions were observed.@*CONCLUSIONS@#Letrozole can delay bone maturation and improve PAH, which can be used with conventional treatment for children with CAH due to 21-OHD, especially for those with high BA and low PAH.