Persistent Müllerian duct syndrome (PMDS) is the presence of Müllerian duct derivatives (fallopian tubes, uterus, and/or the upper part of the vagina) in what would be considered a genetically and otherwise physically normal male. In humans, PMDS typically is due to an autosomal recessive congenital disorder and is considered by some to be a form of pseudohermaphroditism due to the presence of Müllerian derivatives. PMDS can also present in non-human animals.
Typical features include undescended testes (cryptorchidism) and the presence of a small, underdeveloped uterus in an XY infant or adult. This condition is usually caused by deficiency of fetal anti-Müllerian hormone (AMH) effect due to mutations of the gene for AMH or the anti-Müllerian hormone receptor, but may also be as a result of insensitivity to AMH of the target organ. as well as inguinal hernias. Adults who have been oblivious to this condition may present with hematuria, which is when blood appears in urine because of hormonal imbalances. PMDS Type I is also referred to as hernia uteri inguinalis, which exhibits one descended testis that has also pulled the fallopian tube, and sometimes uterus, through the inguinal canal. With the AMHR2 gene mutation (PMDS Type 2), the AMHR2 is either not produced, produced in deficient amounts, defective, or the Müllerian ducts manifested a resistance to AMH.
The condition occurs in males and consists of normal-functioning reproductive organs and gonads, but also female reproductive organs such as the uterus and the fallopian tubes. The fetus has two sets of tubes which give rise to accessory reproductive organs - the (Wolffian) mesonephric ducts and the (Müllerian) paramesonephric ducts. Usually, the Wolffian duct gives rise to male reproductive organs (specifically the testicle, epididymis and vas deferens) while the Müllerian to female (the fallopian tubes, the uterus and the vagina), while the other duct regresses. In PMDS, an abnormality in the anti-Müllerian hormone signaling pathway causes the in-males-redundant Müllerian duct to persist and give rise to variously developed female reproductive organs.
PMDS has various causes related to AMH or receptor abnormalities. For example, AMH has failed to synthesize, failed to release or was secreted at the wrong time. Normally, both the Müllerian and Wolffian ducts are present during the 7th week of gestation. At approximately the end of the 7th and the beginning of the 8th week of gestation, the Sertoli cell's secretion of AMH occurs, causing male sex differentiation during fetal development. PMDS is usually coincidentally found during surgery for inguinal hernia, or when searching for adult male infertility causes.
Other diagnostic tests
Genetic
Another method for the confirmation of PMDS is genetic testing. PMDS patients display low levels of AMH within the serum, and low levels of testosterone. The Müllerian structures and cryptorchidism can also develop into cancer, although rare. If PMDS is found during adulthood, or if Müllerian structures had to be left behind due to risks in surgery, biopsies of the remaining Müllerian structures can be performed. Upon pathohistological observation, the endometrial tissues appear atrophied, and the fallopian tubes have begun to congest showing signs of fibrosis.