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- What are the causes of premature testicular enlargement without precocious
puberty?
The causes of premature testicular enlargement (symmetrical or asymmetrical)
without precocious puberty include infiltrative disorders like amyloidosis, sar-
coidosis, tuberculosis, lymphoma, and fragile X syndrome. - What is fragile X syndrome?
Fragile X syndrome is an X-linked dominant disorder characterized by typical
facies (long and narrow face, large ears, prominent forehead, and macrognathia),
flat foot, and hyperextensible fingers. Intellectual disability is the key abnormal-
ity and is more common in affected males as compared to females. It may be
accompanied with autistic behavior and social anxiety. Although enlargement of
the testes may occur during prepubertal period, macroorchidism (testicular vol-
ume >30 ml) is observed only after the onset of puberty. The presence of mac-
roorchidism and intellectual disability is the hallmark abnormalities of fragile X
syndrome. Macroorchidism is related to increased connective tissue component
rather than due to expansion of seminiferous tubules. The disorder is due to
mutations in the FMR (fragile X mental retardation) gene. This gene is abun-
dantly expressed in the brain and testes and encodes for a protein which is essen-
tial for neuronal synaptic plasticity and explains the intellectual disability in
these patients; however, the mechanism of macroorchidism remains elusive
(Fig. 6.8).6 Precocious Puberty