UK guidance on the initial evaluation of an infant or an adolescent with a suspected disorder of sex development

Abstract

It is paramount that any child or adolescent with a suspected disorder of sex development (DSD) is assessed by an experienced clinician with adequate knowledge about the range of conditions associated with DSD. If there is any doubt, the case should be discussed with the regional team. In most cases, particularly in the case of the newborn, the paediatric endocrinologist within the regional DSD team acts as the first point of contact. The underlying pathophysiology of DSD and the strengths and weaknesses of the tests that can be performed should be discussed with the parents and affected young person and tests undertaken in a timely fashion. This clinician should be part of a multidisciplinary team experienced in management of DSD and should ensure that the affected person and parents are as fully informed as possible and have access to specialist psychological support. Finally, in the field of rare conditions, it is imperative that the clinician shares the experience with others through national and international clinical and research collaboration.

Fig. 1

Calculating the External Masculinisation Score provides an objective aggregate score of the extent of masculinization of the external genitalia. Each individual feature of the genitalia (phallus size, labioscrotal fusion, site of the gonads and location of urethral meatus) can be individually scored to provide a score out of 12. ¹Microphallus refers to a phallus below the male reference range. ²L/S, labioscrotal; Ing, inguinal; Ab, abdominal or absent on examination.

Fig. 2

Approach to investigating adolescent girls with primary amenorrhoea.

Fig. 3

Role of the clinical genetics service within the specialist DSD team. FISH, fluorescence in situ hybridization; MLPA, Multiplex Ligation-dependent Probe Amplification.

Fig. 4

Interpretation of the results of the human chorionic gonadotrophin (hCG) stimulation test when investigating XY DSD and pointers for consideration of prolonged hCG stimulation and adrenocorticotrophin hormone stimulation. ¹Prolonged hCG stimulation test should be considered in those cases where there is a poor testosterone (T) response to a standard hCG stimulation test. ²Synacthen stimulation test should be considered in those cases who show a poor testosterone response to hCG stimulation. 46,XY children with lipoid congenital adrenal hyperplasia due to a steroidogenic acute regulatory defect or P450scc deficiency due to CYP11A1 defect will have female genitalia and present in a salt-losing state in the first days or weeks of life before synacthen performed.