Thyroid disorders (TD) represent a remarkable share of all the late morbidities experienced following pediatric haematopoietic stem cell transplantation (HSCT), with long-term reported occurrence often exceeding 70%. In addition, the data collected on wide cohorts of survivors assessed longitudinally outlined a progressive increase in the cumulative incidence of TD as far as 30 years following transplantation. Accordingly, a life-long monitoring of thyroid health is warranted among patients exposed to HSCT in childhood, in order to early detect TD and undertake a prompt dedicated treatment. Although several national and international consortia have provided recommendations for the early detection of thyroid disorders among childhood cancer survivors exposed to radiotherapy and alkylating agents, no guidelines specifically and thoroughly focused on HSCT-related TD have been published to date. As stem cell transplantation has become the standard-of-care in a growing body of non-oncological conditions, this urge has become pivotal. To highlight the challenging issues specifically involving this cohort of patients and to provide clinicians with the proposal of a practical follow-up protocol, we reviewed published literature in the light of the shared experience of a multidisciplinary team of pediatric oncologists, transplantologists, pathologists and endocrinologists involved in the long-term care of HSCT survivors. As a final result, we hereby present the proposals of a practical and customized risk-based approach to tailor thyroid health follow-up based on HSCT-related detrimental factors.

The case of mini-puberty in a 6-month-old infant born preterm is described. The authors discuss the clinical differences of mini-puberty in term and preterm newborns.

An adrenocortical adenoma was diagnosed in a 4-year-old boy presenting with high growth rate, pubic hair and frequent penal erection.

Thyroid function disorders represent the most frequently detected medical complication among patients with trisomy 21, with a reported prevalence ranging from 4-8% in childhood to 50% or more in adulthood. Over 1% of newborns with Down syndrome show clinical and/or biochemical signs consistent with congenital hypothyroidism, overall, promptly identified by means of the neonatal screening. The 30% of patients are diagnosed with transient congenital hypothyroidism, while 70% show a lifelong need for hormonal replacement therapy with levothyroxine. Afterwards, non-autoimmune subclinical hypothyroidism represents the most frequent finding, with reported prevalence ranging from 23 to 60%. It is still controversial whether subclinical hypothyroidism can be labelled as a pathological condition or represents the expression of a mere asymptomatic upwards shift of TSH, with no clinical impact. In addition, syndrome-related abnormalities in the mechanisms underlying immune tolerance result in a greater occurrence of autoimmune disorders. Graves’ disease and autoimmune hypothyroidism in the setting of Hashimoto thyroiditis are experienced by almost 30% of Down patients. Finally, it is not infrequent that the latter clinical picture switches into hyperthyroidism and vice versa, in an unpredictable clinical continuum. Given the increased lifelong risk of experiencing thyroid function disorders in children and adolescents with Down syndrome, a systematic periodic clinical and biochemical assessment is recommended, in order to promptly detect and eventually treat pathological conditions.