Clinical_Rounds_in_Endocrinology_Volume_II_-_Pediatric_Endocrinology

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41. Does CDGP and congenital idiopathic hypogonadotropic hypogonadism
    represent a spectrum of a common disorder?
    A strong family history of delayed puberty is present in majority of children
    with CDGP. Similarly, 10 % of patients with congenital idiopathic hypogo-
    nadotropic hypogonadism (IHH) also have a family history of delayed
    puberty. It has also been shown that CDGP and congenital IHH may coexist
    in the same family pedigree. This suggests that CDGP and congenital IHH
    represent a spectrum of aberration in pubertal development, with CDGP and
    permanent congenital IHH at two extremes, with reversible IHH in between.
    Recently, a study has shown that individuals with CDGP had higher preva-
    lence of inactivating mutations of TAC3 gene, which is classically associated
    with congenital IHH.


42. A 15-year-old boy presented with poor development of secondary sexual char-
    acteristics and short stature. His father also had a history of delayed puberty.
    What is the most likely diagnosis?
    The most likely diagnosis in the index child is constitutional delay in growth
    and puberty (CDGP). It is difficult to differentiate between CDGP and congeni-
    tal idiopathic hypogonadotropic hypogonadism; however, there are some clini-
    cal pointers which help to differentiate between the two disorders, and these are
    enlisted in the table given below.

Parameters CDGP Congenital IHH

Presenting manifestation Growth failure and

delayed puberty

Delayed puberty

Family history Strong family history

of “late bloomer”

Familial clustering is known

Neonatal manifestations Absent Micropenis, cryptorchidism, and

midline defects

Anosmia/hyposmia Absent May be present

Neuroskeletal abnormalities Absent May be present

Height velocity Normal Normal

Pubarche Delayed Normal/delayed

Testicular volume >4 ml May be present Less common

Bone age >12 years for boys or

>11 years for girls

Unlikely Likely

Final adult height Within range for

target height

Exceeds target height

Although the presence of eunuchoidal body proportions is a classical feature of

congenital IHH, patients with CDGP can also have eunuchoidal body propor-

tions. This is because of poor spine growth due to delay in exposure to gonadal

steroids.

7 Delayed Puberty