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Encyclopedia > Cryptorchidism
Cryptorchidism
Classification & external resources
ICD-10 Q53
ICD-9 752.5

Cryptorchidism is a medical term referring to absence from the scrotum of one or both testes. This usually represents failure of the testis to move, to "descend," during fetal development from an abdominal position, through the inguinal canal, into the ipsilateral scrotum. About 3% of full-term and 30% of premature infant boys are born with at least one undescended testis, making cryptorchidism the most common birth defect of male genitalia. However, most testes descend by the first year of life (the majority within three months), making the true incidence of cryptorchidism around 1% overall. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following codes are used with International Statistical Classification of Diseases and Related Health Problems. ... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... In some male mammals, the scrotum is a protuberance of skin and muscle containing the testicles. ... Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... The abdomen is a part of the body. ... The inguinal canal is a passage in the anterior abdominal wall which in men conveys the spermatic cord and in women the round ligament. ... A congenital disorder is a medical condition or defect that is present at or before birth (for example, congenital heart disease). ... A sex organ, or primary sexual characteristic, narrowly defined, is any of those parts of the body (which are not always bodily organs according to the strict definition) which are involved in sexual reproduction and constitute the reproductive system in an complex organism; namely: Male: penis (notably the glans penis...


A testis absent from the normal scrotal position can be:

  1. found anywhere along the "path of descent" from high in the posterior (retroperitoneal) abdomen, just below the kidney, to the inguinal ring;
  2. found in the inguinal canal;
  3. ectopic, that is, found to have "wandered" from that path, usually outside the inguinal canal and sometimes even under the skin of the thigh, the perineum, the opposite scrotum, and femoral canal;
  4. found to be undeveloped (hypoplastic) or severely abnormal (dysgenetic);
  5. found to have vanished (also see Anorchia).

About two thirds of cases without other abnormalities are unilateral; 1/3 involve both testes. In 90% of cases an undescended testis can be palpated (felt) in the inguinal canal; in a minority the testis or testes are in the abdomen or nonexistent (truly "hidden"). It has been suggested that Renal anomalies and Renal plasma threshold be merged into this article or section. ... Anorchia, is a medical condition where both testes are absent at birth. ...


Undescended testes are associated with reduced fertility, increased risk of testicular cancer and psychological problems when the boy is grown. Undescended testes are also more susceptible to testicular torsion and infarction and inguinal hernias. To reduce these risks, undescended testes are usually brought into the scrotum in infancy by a surgical procedure called an orchiopexy. Fertility is a measure of reproduction: the number of children born per couple, person or population. ... Testicular cancer is a type of cancer that develops in the testicles, a part of the male reproductive system. ... In testicular torsion the spermatic cord that provides the blood supply to a testicle is twisted, cutting off the blood supply, often causing orchalgia. ... Orchiopexy is surgery to move an undescended testicle into the scrotum. ...


Although cryptorchidism nearly always refers to congenital absence or maldescent, a testis observed in the scrotum in early infancy can occasionally "reascend" (move back up) into the inguinal canal. A testis which can readily move or be moved between the scrotum and canal is referred to as retractile.

Contents

Terminology

Cryptorchidism is derived from the Greek words "crypto" (meaning "hidden") and "orchid" (meaning "testicle"). During the last century, cryptorchidism was sometimes restricted to the subset of undescended testes that were not palpable above the scrotum or in the inguinal canal — those that were truly hidden in the abdomen or completely absent. In recent decades the distinction is no longer made in most contexts, and the two terms are used interchangeably. Cryptorchism is an older variant of the same term.


Normal fetal testicular development and descent

The testes begin as an immigration of primordial germ cells into testicular cords along the genital ridge in the abdomen of the early embryo. The interaction of several male genes organizes this developing gonad into a testis rather than an ovary by the second month of gestation. During the 3rd to 5th months, the cells in the testes differentiate into testosterone-producing Leydig cells, and anti-müllerian hormone-producing Sertoli cells. The germ cells in this environment become fetal spermatogonia. Male external genitalia during the 3rd and 4th months of gestation and the fetus continues to grow, develop, and differentiate. A germ cell is a kind of cell that is part of the germline, and is involved in the reproduction of organisms. ... In embryology, the gonadal ridge (or genital ridge) is the precursor to the gonads. ... For other meanings of this term, see gene (disambiguation). ... Testosterone is a steroid hormone from the androgen group. ... Leydig cells, also known as interstitial cells of Leydig, are found adjacent to the seminiferous tubules in the testes. ... Anti-Müllerian hormone (AMH) is a dimeric glycoprotein that inhibits the development of the Müllerian ducts in a male embryo. ... A Sertoli cell (a kind of sustentacular cell) is a nurse cell of the testes which is part of a seminiferous tubule. ...


The testes remain high in the abdomen until the 7th month of gestation, when they move from the abdomen through the inguinal canals into the two sides of the scrotum. It has been proposed that movement occurs in two phases, under control of somewhat different factors. The first phase, movement across the abdomen to the entrance of the inguinal canal appears controlled (or at least greatly influenced) by anti-müllerian hormone (AMH). The second phase, in which the testes move through the inguinal canal into the scrotum, is dependent on androgens (most importantly testosterone). In rodents, androgens induce the genitofemoral nerve to release calcitonin gene-related peptide (CGRP), which produces rhythmic contractions of the gubernaculum, a ligament which connects the testis to the scrotum, but a similar mechanism has not been demonstrated in humans. Maldevelopment of the gubernaculum, or deficiency or insensitivity to either AMH or androgen therefore can prevent the testes from descending into the scrotum. Some evidence suggests there may even be an additional paracrine hormone, referred to as descendin, secreted by the testes. Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors. ... In human anatomy, the genitofemoral nerve originates from the upper part of the lumbar plexus of spinal nerves. ... Calcitonin gene related peptide (CGRP) is derived, with calcitonin, from the CT/CGRP gene located on chromosome 11. ... The gubernaculum is a fold of peritoneum which attaches to the caudal end of the testes. ... A ligament is a short band of tough fibrous connective tissue composed mainly of long, stringy collagen fibres. ... Paracrine signalling is a form of signalling in which the target cell is close to the signal releasing cell, and the signal chemical is broken down too quickly to be carried to other parts of the body. ...


In many infants with inguinal testes, further descent of the testes into the scrotum occurs in the first 6 months of life. This is attributed to the postnatal surge of gonadotropins and testosterone that normally occurs between the first and fourth months of life. Gonadotropins are protein hormones secreted by gonadotrope cells of the pituitary gland of vertebrates. ...


Spermatogenesis continues after birth. In the 3rd to 5th months of life, some of the fetal spermatogonia residing along the basement membrane become type A spermatogonia. More gradually, other fetal spermatogonia become type B spermatogonia and primary spermatocytes by the 5th year after birth. Spermatogenesis arrests at this stage until puberty. This article or section is in need of attention from an expert on the subject. ... ... Puberty refers to the process of physical changes by which a childs body becomes an adult body capable of reproduction. ...


Most normal-appearing undescended testis are also normal by microscopic examination, but reduced spermatogonia can be found. The tissue in undescended testes becomes more markedly abnormal ("degenerates") in microscopic appearance between 2 and 4 years after birth. There is some evidence that early orchiopexy reduces this degeneration.


Causes of cryptorchidism

In most full-term infant boys with cryptorchidism but no other genital abnormalities, a cause cannot be found, making this a common, sporadic, unexplained birth defect.


Although severely premature infants can be born before descent of testes, there is a strong association of cryptorchidism with low birthweight due to either prematurity or intrauterine growth retardation. In these infants there is usually no evidence of hormonal malfunction. Associated inguinal hernias are common. Prematurity is the condition of being born before a full gestation. ... Intrauterine growth retardation or Intrauterine growth restriction (IUGR) refers to the condition during pregnancy where a fetus is considered to be too small for its gestational age (generally in the 10th percentile). ...


Hormonal abnormalities (deficiency or insensitivity to androgens or anti-müllerian hormone) can be demonstrated in a high proportion of those with evidence of undervirilization or ambiguity such as hypospadias or micropenis. In biology and medicine, virilization refers to the development of changes which make a male body different from a female body. ... An intersexual is a person (or individual of any unisexual species) who is born with genitalia and/or secondary sexual characteristics of indeterminate sex, or which combine features of both sexes. ... Hypospadias is a birth defect of the urethra in the male that involves an abnormally placed urethral meatus (opening). ... Micropenis is a medical term that describes an unusually small penis in a human male. ...


A contributing role of environmental chemicalsendocrine disruptors — that interfere with normal fetal hormone balance has been proposed as well, similar to the effects of diethylstilbestrol exposure. It is rarely possible to implicate a specific chemical exposure for an individual child. A chemical substance is any material substance used in or obtained by a process in chemistry: A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions. ... Endocrine disruptors are substances which interfere with the endocrine system by mimicking, blocking or otherwise disrupting the function of hormones. ... Diethylstilbestrol (DES) is a drug, a synthetic nonsteroidal estrogen that was first synthesized in 1938. ...


Occasional instances of other genetic defects involving development or function of the gubernaculum have been reported. Homeobox gene mutations can cause cryptorchidism in animals but remain a largely theoretical possibility in humans. A homeobox is a DNA sequence found within genes that are involved in the regulation of development (morphogenesis) of animals, fungi and plants. ... For other meanings of this term, see gene (disambiguation). ... It has been suggested that mutant be merged into this article or section. ...


Rare iatrogenic cases have also been reported in which hernia repair or other surgery in the inguinal area resulted in trapping of a testis above the scrotum.


A 2006 study showed that regular alcohol consumption during pregnancy (5 or more drinks per week) is associated with a 3x increase in cryptorchidism, when compared to non-drinking mothers. Other previously known risk factors include exposure to pesticides, low birth weight (including premature birth), gestational diabetes and being a twin [1].


Inheritance and recurrence risk of cryptorchidism

A small percentage of cases of isolated cryptorchidism are familial. It has been reported that about 4% of fathers and 6-10% of brothers of affected boys have also had cryptorchidism. Few specific genes associated with isolated cryptorchidism have been identified.


In contrast, many of the genes causing some of the intersex conditions associated with androgen or AMH deficiency or insensitivity have been identified, and genetic counseling to explain recurrence risk to families is appropriate. Genetic counseling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning in order to prevent, avoid or...


Associations

Cryptorchidism occurs at a much higher rate in a large number of congenital malformation syndromes. Among the more common are Prader-Willi syndrome, Noonan syndrome, and cloacal exstrophy. A congenital disorder is a medical condition that is present at birth. ... Prader-Willi Syndrome is a genetic disorder, in which seven genes (or some subset thereof) on chromosome 15 are missing or unexpressed (chromosome 15q partial deletion) on the paternal chromosome. ... Noonan Syndrome (NS) is a relatively common congenital genetic condition which affects both males and females. ... Cloacal exstrophy is a severe birth defect wherein much of the abdominal organs (the bladder and intestines) are exposed. ...


Diagnostic evaluation

The most common diagnostic dilemma in otherwise normal boys is distinguishing a retractile testis from a testis that will not/cannot descend spontaneously into the scrotum. Retractile testes are more common than truly undescended testes and do not need to be operated on. In normal males, as the cremaster muscle relaxes or contracts, the testis moves lower or higher ("retracts") in the scrotum. This cremasteric reflex is much more active in infant boys than older men. A retractile testis high in the scrotum can be difficult to distinguish from a position in the lower inguinal canal. Though there are various maneuvers used to do so, such as using a crosslegged position, soaping the examiner's fingers, or examining in a warm bath, the benefit of surgery in these cases can be a matter of clinical judgement. The cremaster muscle is a muscle that covers the testis. ... Cremasteric Reflex is a reflex in males only. ...


In the minority of cases with bilaterally non-palpable testes, further testing to locate the testes, assess their function, and exclude additional problems is often useful. Pelvic ultrasound or magnetic resonance imaging can often, but not invariably, locate the testes while confirming absence of a uterus. A karyotype can confirm or exclude forms of dysgenetic primary hypogonadism, such as Klinefelter syndrome or mixed gonadal dysgenesis. Hormone levels (especially gonadotropins and AMH) can help confirm that there are hormonally functional testes worth attempting to rescue, as can stimulation with a few injections of human chorionic gonadotropin to elicit a rise of the testosterone level. Occasionally these tests reveal an unsuspected and more complicated intersex condition. Ultrasound is sound with a frequency greater than the upper limit of human hearing, this limit being approximately 20 kilohertz (20,000 hertz). ... Magnetic Resonance Image showing a median sagittal cross section through a human head. ... Karyogram of human male using Giemsa staining. ... XXY karyotype Klinefelters syndrome is a condition caused by a chromosome abnormality in males (specifically, a nondisjunction); sufferers have a pair of X sex chromosomes instead of just one. ... Mixed gonadal dysgenesis refers to a condition of abnormal and asymmetrical gonadal development leading to a disturbed sex differentiation. ... Human chorionic gonadotropin (hCG) is a peptide hormone produced in pregnancy, that is made by the embryo soon after conception and later by the syncytiotrophoblast (part of the placenta). ... An intersexual is a person (or individual of any unisexual species) who is born with genitalia and/or secondary sexual characteristics of indeterminate sex, or which combine features of both sexes. ...


In the even smaller minority of cryptorchid infants who have other obvious birth defects of the genitalia, further testing is crucial and has a high likelihood of detecting an intersex condition or other anatomic anomalies. Ambiguity can indicate either impaired androgen synthesis or reduced sensitivity. The presence of a uterus by pelvic ultrasound suggests either persistent müllerian duct syndrome (AMH deficiency or insensitivity) or a severely virilized genetic female with congenital adrenal hyperplasia. An unambiguous micropenis, especially accompanied by hypoglycemia or jaundice, suggests congenital hypopituitarism. An intersexual is a person (or individual of any unisexual species) who is born with genitalia and/or secondary sexual characteristics of indeterminate sex, or which combine features of both sexes. ... Androgen insensitivity syndrome (AIS, or Androgen resistance syndrome) is a set of disorders of sexual differentiation that results from mutations of the gene encoding the androgen receptor. ... The uterus or womb is the major female reproductive organ of most mammals, including humans. ... Ultrasound is sound with a frequency greater than the upper limit of human hearing, this limit being approximately 20 kilohertz (20,000 hertz). ... Persistent müllerian duct syndrome (PMDS) refers to the presence of a uterus and sometimes other müllerian duct derivatives in a male. ... Congenital adrenal hyperplasia (CAH) refers to any of several autosomal recessive diseases resulting from defects in steps of the synthesis of cortisol from cholesterol by the adrenal glands. ... Micropenis is a medical term that describes an unusually small penis in a human male. ... Hypoglycemia (hypoglycæmia in the UK) is a medical term referring to a pathologic state produced by a lower than normal amount of sugar (glucose) in the blood. ... Jaundice, also known as icterus (attributive adjective: icteric), is a yellowing of the skin, conjunctiva (clear covering over the sclera, or whites of the eyes) and mucous membranes caused by increased levels of bilirubin in the human body (or the body of another red blooded animal). ... Hypopituitarism is a medical term describing deficiency (hypo) of one or more hormones of the pituitary gland. ...


Management of cryptorchidism

The primary management of cryptorchidism is surgery, called orchiopexy. It is usually performed in infancy, if inguinal testes have not descended after 4-6 months, often by a pediatric urologist or pediatric surgeon, but in many communities still by a general urologist or surgeon. Pediatric urology is a surgical subspecialty of medicine dealing with the disorders of childrens genitourinary systems. ... Pediatric surgery is a subspecialty of surgery involving the surgery of fetuses, infants, children, adolescents, and young adults. ... Urology is the field of medicine that focuses on the urinary tracts of males and females, and of the male reproductive system. ...


When the undescended testis is in the inguinal canal, hormonal therapy is sometimes attempted and occasionally successful. The most commonly used hormone therapy is human chorionic gonadotropin. A series of hCG injections (10 injections over 5 weeks is common) is given and the status of the testis/testes is reassessed at the end. Although many trials have been published, the reported success rates range widely, from roughly 5 to 50%, probably reflecting the varying criteria for distinguishing retractile testes from low inguinal testes. Hormone treatment does have the occasional incidental benefits of allowing confirmation of Leydig cell responsiveness (proven by a rise of the testosterone by the end of the injections) or inducing additional growth of a small penis (via the testosterone rise). Some surgeons have reported facilitation of surgery, perhaps by enhancing the size, vascularity, or healing of the tissue. A newer hormonal intervention used in Europe is use of GnRH analogs such as nafarelin or buserelin; the success rates and putative mechanism of action are similar to hCG, but some surgeons have combined the two treatments and reported higher descent rates. Limited evidence suggests that germ cell count is slightly better after hormone treatment; whether this translates into better sperm counts and fertility rates at maturity has not been established. The cost of either type of hormone treatment is less than that of surgery and the chance of complications at appropriate doses is minimal. Nevertheless, despite the potential advantages of a trial of hormonal therapy, many surgeons do not consider the success rates high enough to be worth the trouble since the surgery itself is usually simple and uncomplicated. A gonadotropin-releasing hormone analog, also known as a GnRH analog, is a class of synthetic peptide drugs modeled on the human hypothalamic gonadotropin-releasing hormone (GnRH) and designed to mimic or antagonize the physiological effects of GnRH for therapeutic purposes. ... Nafarelin is a gonadotropin releasing hormone agonist (GnRH agonist). ... Buserelin is a gonadotropin releasing hormone agonist (GnRH agonist). ...


In cases where the testes are identified preoperatively in the inguinal canal, orchiopexy is often performed as an outpatient and has a very low complication rate. An incision is made over the inguinal canal. The testis with accompanying cord structure and blood supply is exposed, partially separated from the surrounding tissues ("mobilized"), and brought into the scrotum. It is sutured to the scrotal tissue or enclosed in a "subdartos pouch." The associated passage back into the inguinal canal, an inguinal hernia, is closed to prevent re-ascent.


Surgery becomes more complicated if the blood supply is not ample and elastic enough to be stretched into the scrotum. In these cases, the supply may be divided, some vessels sacrificed with expectation of adequate collateral circulation. In the worst case, the testis must be "auto-transplanted" into the scrotum, with all connecting blood vessels cut and reconnected ("anastomosed"). // Anastomosis (plural anastomoses) refers to a form of network in which streams both branch out and reconnect. ... // Anastomosis (plural anastomoses) refers to a form of network in which streams both branch out and reconnect. ...


When the testis is in the abdomen, the first stage of surgery is exploration to locate it, assess its viability, and determine the safest way to maintain or establish the blood supply. Multi-stage surgeries, or auto-transplantation and anastomosis, are more often necessary in these situations. Just as often, intra-abdominal exploration discovers that the testis is non-existent ("vanished"), or dysplastic and not salvageable. Anorchia, is a medical condition where both testes are absent at birth. ...


The principal major complication of all types of orchiopexy is loss of the blood supply to the testis, resulting in loss of the testis due to ischemic atrophy or fibrosis. In medicine, ischemia (Greek ισχαιμία, isch- is restriction, hema or haema is blood) is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. ... Atrophy is the partial or complete wasting away of a part of the body. ... Fibrosis is the formation or development of excess fibrous connective tissue in an organ or tissue as a reparative or reactive process, as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue. ...


Later fertility

Many men who were born with undescended testes have reduced fertility, even after orchiopexy in infancy. The reduction with unilateral cryptorchidism is subtle, with a reported infertility rate of about 10%, compared with about 6% reported by the same study for the general population of adult men. Fertility is a measure of reproduction: the number of children born per couple, person or population. ...


The fertility reduction after orchiopexy for bilateral cryptorchidism is more marked, about 38%, or 6 times that of the general population. The basis for the universal recommendation for early surgery is research showing degeneration of spermatogenic tissue and reduced spermatogonia counts after the second year of life in undescended testes. The degree to which this is prevented or improved by early orchiopexy is still uncertain.


At least one contributing mechanism for reduced spermatogenesis in cryptorchid testes is temperature. The temperature of testes in the scrotum is at least a couple of degrees cooler than in the abdomen. Animal experiments in the middle of the 20th century suggested that raising the temperature could damage fertility. Some circumstantial evidence suggests tight underwear and other practices that raise testicular temperature for prolonged periods can be associated with lower sperm counts. Nevertheless, research in recent decades suggests that the issue of fertility is more complex than a simple matter of temperature. It seems likely that subtle or transient hormone deficiencies or other factors that lead to lack of descent also impair the development of spermatogenic tissue. The sperm count is a measure of fertility in a man. ...


The inhibition of spermatogenesis by ordinary intra-abdominal temperature is so potent that continual suspension of normal testes tightly against the inguinal ring at the top of the scrotum by means of special "suspensory briefs" has been researched as a method of male contraception, and was referred to as "artificial cryptorchidism" by one report. A male contraceptive is a device or a drug used by a man that prevents conception in his female partner. ...


An additional factor contributing to infertility is the high rate of anomalies of the epididymis in boys with cryptorchidism (over 90% in some studies). Even after orchiopexy, these may also affect sperm maturation and motility at an older age. Male Anatomy The epididymis is part of the human male reproductive system and is present in all male mammals. ...


Later cancer risk

One of the strongest arguments for early orchiopexy is prevention of testicular cancer. About 1 in 500 men born with one or both testes undescended develops testicular cancer, roughly a 4- to 40-fold increased risk. The peak incidence occurs in the 3rd and 4th decades of life. The risk is higher for intra-abdominal testes and somewhat lower for inguinal testes, but even the normally descended testis of a man whose other testis was undescended has about a 20% higher cancer risk than those of other men. Testicular cancer is a type of cancer that develops in the testicles, a part of the male reproductive system. ...


The most common type of testicular cancer occurring in undescended testes is seminoma. It is usually treatable if caught early, so urologists often recommend that boys who had orchiopexy as infants be taught testicular self-examination, to recognize testicular masses and seek early medical care for them. Cancer developing in an intra-abdominal testis would be unlikely to be recognized before considerable growth and spread, and one of the advantages of orchiopexy is that a mass developing in a scrotal testis is simply far easier to recognize than an intra-abdominal mass. Testicular cancer is a type of cancer that develops in the testicles, a part of the male reproductive system. ... As testicular cancer is a significant killer of males, doctors recommend monthly self-examination. ...


Although orchiopexy makes cancer more easily recognizable at an early stage, whether early orchiopexy actually reduces the chance of developing cancer remains a subject of controversy. As with infertility, the causes of cancer associated with cryptorchidism are not known. Most evidence suggests the cancer risk is due to an inherent abnormality of the undescended testis rather than to the ability of an abdominal location to cause cancer in an otherwise normal testis.


The risk of malignancy in the undescended testis is 4 to 10 times higher than that in the general population and is approximately 1 in 80 with a unilateral undescended testis and 1 in 40 to 1 in 50 for bilateral undescended testes. The peak age for this tumor is 15–45 yr. The most common tumor developing in an undescended testis is a seminoma (65%); in contrast, after orchiopexy, seminomas represent only 30% of testis tumors.


Cryptorchidism in animals

Dogs

Cryptorchidism is a common occurrence in dogs and is thought to be a sex-limited autosomal recessive trait.[1] It is found in up to 10 percent of male dogs.[2] Dog testes usually descend by ten days of age and it is considered to be cryptorchidism if they do not descend by the age of eight weeks.[3] Cryptorchidism can be either bilateral (causing sterility) or unilateral, and inguinal or abdominal (or both). Because it is an inherited trait, affected dogs should not be bred and should be castrated. The parents should be considered carriers of the defect and not be bred. Littermates may be normal, carriers, or cryptorchid. Castration should be performed on cryptorchid dogs also due to the high rate of testicular cancer, especially sertoli cell tumors.[3] The incidence of testicular cancer is 13.6 times higher in dogs with abdominally retained testicles compared with normal dogs.[2] Testicular torsion is also more likely in retained testicles. Surgical correction is by palpation of the retained testicle and subsequent exploration of the inguinal canal or abdomen. It has been suggested that this article or section be merged into Dominance relationship. ... Spaying and neutering are the respective processes of female and male animal sterilization, in order to keep them from producing offspring. ... A Sertoli cell (a kind of sustentacular cell) is a nurse cell of the testes which is part of a seminiferous tubule. ... In testicular torsion the spermatic cord that provides the blood supply to a testicle is twisted, cutting off the blood supply, often causing orchalgia. ...


Commonly affected breeds[1]

Inguinal cryptorchidism in a Chihuahua
Inguinal cryptorchidism in a Chihuahua

Image File history File linksMetadata Size of this preview: 800 × 600 pixels Full resolution (2592 × 1944 pixel, file size: 744 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Cryptorchidism Metadata This file contains... Image File history File linksMetadata Size of this preview: 800 × 600 pixels Full resolution (2592 × 1944 pixel, file size: 744 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Cryptorchidism Metadata This file contains... The Boxer is a breed of stocky, medium-sized, short-haired dog with a smooth fawn or brindled coat and square-jawed muzzle. ... This article or section does not adequately cite its references or sources. ... The dachshund is a short-legged, elongated dog breed of the hound family. ... Country of origin United Kingdom Classification Breed standards (external links) FCI, AKC, ANKC KC(UK), NZKC, UKC The English Bulldog, often called simply the Bulldog, is a medium-sized dog breed that originated in the United Kingdom. ... The Miniature Schnauzer is a breed of small dog of the Schnauzer type that originated in Germany in the mid-to-late 19th century. ... Pekingese or Pekinese is an ancient breed of toy dog, originating in China. ... Country of origin Poland and Germany Common nicknames Classification and breed standards The Pomeranian is a breed of dog in the spitz family, named for the Pomerania region of Poland and East Germany, and classed as a toy dog breed because of its small size. ... The Poodle is a breed of dog. ... This article or section does not cite its references or sources. ... For other uses, see Whippet (disambiguation). ... The Yorkshire Terrier, (diminutive / nickname: Yorkie), is a breed of small dog in the toy category. ...

Cats

Cryptorchidism is a more rare condition in cats than it is in dogs. In one study 1.9 percent of intact male cats were cryptorchid.[4] Persians are predisposed.[5] Normally the testicles are present in the scrotum by the age of six to eight weeks. Urine spraying is one indication that a cat with no observable testicles may not be neutered; other signs are the presence of enlarged jowls, thickened facial and neck skin, and spines present on the penis (which usually regress within six weeks after castration).[6] Most cryptorchid cats present with an inguinal testicle.[7] Testicular tumors and testicular torsion are rare in cryptorchid cats, but castration is usually performed due to unwanted behavior such as urine spraying. The Persian cat is one of the oldest breeds of cat. ...


Trivia

"Cryptorchid" is the title of track 6 of industrial band Marilyn Manson's album Antichrist Superstar. Brian Hugh Warner (born January 5, 1969), better known by his stage name Marilyn Manson, is a musician and artist known for his outrageous stage persona and image as the lead singer of the band that bears the same name. ... Antichrist Superstar (written Antichrist Svperstar in several places as an allusion to Latin) is Marilyn Mansons second full-length studio release and was released in 1996. ...


References

  • Docimo SG. The results of surgical therapy for cryptorchidism: a literature review and analysis. J Urol 1995 Sep; 154(3): 1148-52. PMID 7637073
  • Kolon TF. Cryptorchidism. Emedicine Emedicine
  • Kolon TF, Patel RP, Huff DS. Cryptorchidism: diagnosis, treatment, and long-term prognosis. Urol Clin North Am. 2004 Aug;31(3):469-80, viii-ix. PMID 15313056
  • Møller H, Cortes D, Engholm G, Thorup J. Risk of testicular cancer with cryptorchidism and with testicular biopsy: cohort study. BMJ. 1998 Sep 12; 317(7160): 729-730. [2]
  1. ^ a b Ettinger, Stephen J.;Feldman, Edward C. (1995). Textbook of Veterinary Internal Medicine, 4th ed., W.B. Saunders Company. ISBN 0-7216-6795-3. 
  2. ^ a b Miller, Nathan A.; Van Lue, Stephen J., Rawlings, Clarence A. (March 15, 2004). "Use of laparoscopic-assisted cryptorchidectomy in dogs and cats". Journal of the American Veterinary Association 224 (6): 875-878. Retrieved on 2006-08-10. 
  3. ^ a b Meyers-Wallen, V.N.. Inherited Abnormalities of Sexual Development in Dogs and Cats. Recent Advances in Small Animal Reproduction. Retrieved on 2006-08-10.
  4. ^ Scott K, Levy J, Crawford P (2002). "Characteristics of free-roaming cats evaluated in a trap-neuter-return program". J Am Vet Med Assoc 221 (8): 1136-8. PMID 12387382. 
  5. ^ Griffin, Brenda (2005). "Diagnostic usefulness of and clinical syndromes associated with reproductive hormones", in August, John R. (ed.): Consultations in Feline Internal Medicine Vol. 5. Elsevier Saunders. ISBN 0-7216-0423-4. 
  6. ^ Memon, M.; Tibary, A. (2001). Canin and Feline Cryptorchidism (PDF). Recent Advances in Small Animal Reproduction. Retrieved on 2007-02-09.
  7. ^ Yates D, Hayes G, Heffernan M, Beynon R (2003). "Incidence of cryptorchidism in dogs and cats". Vet Rec 152 (16): 502-4. PMID 12733559. 

For the Manfred Mann album, see 2006 (album). ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian calendar. ... For the Manfred Mann album, see 2006 (album). ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian calendar. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ... February 9 is the 40th day of the year in the Gregorian calendar. ...

External links


  Results from FactBites:
 
eMedicine - Cryptorchidism : Article by Thomas F Kolon, MD (5038 words)
Cryptorchidism literally means hidden or obscure testis and generally refers to an undescended or maldescended testis.
Cryptorchidism is identified in 1.5-4% of fathers and 6.2% of brothers of patients with cryptorchidism.
Cryptorchidism may be a variant of hypogonadotropic hypogonadism.
  More results at FactBites »

 
 

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