Epidemiology and pathogenesis of cryptorchidism

Abstract

Prospective clinical studies have shown that the prevalence of cryptorchidism among boys with birth weight > or =2500 g has increased in UK from 2.7 to 4.1% between the 1950s and the 1980s and in Denmark from 1.8 to 8.4% between the 1950s and the 1990s. In similar studies performed in different countries during the last two decades the figures have varied from 2.1 to 8.4%. Due to spontaneous descent of the testes lower figures, i.e. between 0.9 and 1.8% have been described at 3 months. Acquired cryptorchidism contributes to the increase in the rate of cryptorchidism in school-aged children. Testicular descent occurs in two phases. During the first phase, before midgestation, testis remains anchored to the inguinal area by insulin like hormone 3 (INSL3)-driven development of the gubernaculum. The second inguinoscrotal phase is dependent on testicular androgens and it is usually completed by the time of birth. Mutations of specific genes have rarely been reported in cryptorchidism. However, several risk factors for cryptorchidism, such as preterm birth and low birth weight, have been described. Environmental factors may also have a role in the etiology of cryptorchidism. Future studies on the gene-environment interaction will give new insights to the pathogenesis of cryptorchidism.

Smoking and its association with cryptorchidism in Down syndrome

“…This is the most frequent urogenital tract abnormality in this population. 22 The high prevalence and drawbacks reinforce the idea that such a condition cannot be neglected in the clinical evaluation of children with Down syndrome.…”

“…21,22,26 Although there are uncertainties whether maternal smoking is associated with congenital defects, positive associations with cryptorchidism were found, but not with hypospadias. 1,22,26 In our series, of the 40 patients with DS, only one (2.5%) presented hypospadias. The low prevalence of this malformation found in this group of patients hinders an assessment of the significance of smoking habit in the genesis of hypospadias in DS boys.…”

“…20,21 It is suspected that the lifestyle of mothers and environmental exposures during pregnancy may interfere with the normal testicular descent, increasing the risk of urogenital malformations. [19][20][21][22] The aims of our study were to evaluate the prevalence of cryptorchidism and its association with parental smoking in patients with Down syndrome.…”

Hypospadiasis előfordulása öt fivérben

“…A hímvessző alsó felszínén elhelyezkedő húgycsőlemez közepén, hosszanti vályúszerű bemélyedés alakul ki, majd ennek a gáttól a makk irányába történő záródása hozza létre a húgycsövet (1. ábra). Ha ezt a folyamatot vezérlő genetikai program hibás vagy a hibátlan genetikai program megvalósulását külső tényező megzavarja, a záródási folyamat nem fejeződik be és ennek következtében húgy-csőhasadék alakul ki [5].…”

A risk assessment of a common drug using xenograft model

“…It affects 2% to 9% of newborn boys (1) and the incidence have been reported to increase (2,3). Cryptorchidism confers an increased risk of infertility and testicular cancer in adulthood (3)(4)(5).…”