Pituitary hyperplasia in childhood primary hypothyroidism: a review

Pituitary hyperplasia following primary hypothyroidism in pediatric age group population is considered rare with reports of unnecessary neurosurgical intervention for this medically treatable condition. Given the paucity of information on this topic, it is timely to provide clinicians with a comprehensive summary of available research. A search of published studies in Pubmed, PsychInfo and Cochrane Database with the terms “pituitary hyperplasia” or “pituitary hypertrophy” and “hypothyroidism” was performed and the results filtered for English language, pediatric (0-18 years) population and CT or MRI confirmed findings. 55 studies met the inclusion criteria. Data for a total of 110 patients with pituitary hyperplasia following primary hypothyroidism were extracted. The study population included 29 males and 81 females (M: F= 0.35:1). Patient age varied from 3 weeks to 18 years with a mean age of 10.22 years. The most common clinical presentations included growth retardation, constipation and features of myxedema which were present in 78, 36 and 18 percent of children included in our review. Neuroimaging showed the mean (SD) pituitary height being 13.48 mm (4.72 mm). All of the patients achieved resolution of their pituitary mass and clinical as well as biochemical abnormalities 1 to 26 months after initiation of thyroid hormone replacement therapy, with an average time interval of 7.22 months. Our review has tried to delve in the pathophysiology as well as clinical, biochemical and radiological aspects of pediatric pituitary hyperplasia secondary to primary hypothyroidism and provide recommendations for treatment and follow-up. This may help anyone concerned gain a substantial knowledge on this topic.