Growth hormone treatment improves vitality and behavioural issues in children with Prader-Willi syndrome.

AIM: Prader-Willi syndrome is a neurogenetic disorder, with characteristics such as obesity, short stature, muscular weakness, intellectual deficiencies and deviant social behaviour. This study evaluated whether growth hormone treatment of children with Prader-Willi syndrome resulted in possible and lasting effects on their cognition and behaviour. METHODS: We randomised six girls and 13 boys to either a treatment group or a control group. The treatment group received growth hormone (Genotropin(®) 0.033 mg/kg/day) for 2 years, while the control group did not receive treatment in the first year and then received a double dose in the second year. Treatment was then stopped in both groups for 6 months. RESULTS: Both groups showed the same intellectual disabilities at the start of the study, and no difference was found after the first and second years. The parents reported that the children showed increased vitality during treatment. When treatment was stopped, the children showed a marked exacerbation of behavioural problems, a significant increase in body fat and a decrease in insulin-like growth factor 1 levels. CONCLUSION: We believe this is the first study to show that abrupt-ceasing growth hormone treatment led to a successive deterioration in behavioural problems in children with Prader-Willi syndrome.

Cryptorchidism: a clinical perspective.

Incomplete descent of the testes is the most common genital anomaly in newborn boys. The prevalence varies with apparent geographical differences. The etiology of cryptorchidism is considered to be multifactorial (genetic, maternal, and environmental factors), and it occurs most often as an isolated disorder with no obvious cause. Cryptorchidism should not be left untreated, since there is an increased risk of developing testicular cancer and infertility/subfertility. However, the mode and timing of treatment, as well as the risks of subfertility and testicular cancer have long been controversial. There is increasing evidence that treatment should be performed early in life. Randomized volumetric and histological studies have shown that early treatment before the age of one year is beneficial for testicular development and future spermatogenesis compared to later treatment. It remains to be proven that this difference persists into adulthood. Due to the low efficacy rate and the possible adverse effects of hormonal treatment, surgery is preferred. The exact optimal time for orchidopexy is not known, but it should probably be before one year of age, at centers with expertise in pediatric anesthesiology and pediatric surgery/urology. The risk of testicular cancer is also reduced if orchidopexy is performed before puberty; however it remains to be proven if treatment in early infancy reduces the risk even further.

Management of undescended testes: how and when?

Incomplete descent of one or both testicles from the abdominal cavity, through the inguinal canal into the scrotum is the most common abnormality in new-born boys; 3-5% are affected. Although a majority of these retained testes will descend spontaneously during the first few months after birth, about one percent of all boys will require some sort of treatment in order to achieve best possible testicular function. Thousands of publications deal with different aspects on cryptorchidism - most of them try to improve the mode of treatment; why, when and how should treatment be delivered? In order to summarize the present state of the art, a consensus conference with experts from the Nordic countries was called in August 2006. The conclusions and the appropriate literature reviews can be found in the May issue of Acta Paediatrica 2007.

Dose-dependent effect of growth hormone on final height in children with short stature without growth hormone deficiency.

CONTEXT: The effect of GH therapy in short non-GH-deficient children, especially those with idiopathic short stature (ISS), has not been clearly established owing to the lack of controlled trials continuing until final height (FH). OBJECTIVE: The aim of the study was to investigate the effect on growth to FH of two GH doses given to short children, mainly with ISS, compared with untreated controls. DESIGN AND SETTING: A randomized, controlled, long-term multicenter trial was conducted in Sweden. INTERVENTION: Two doses of GH (Genotropin) were administered, 33 or 67 microg/kg.d; control subjects were untreated. SUBJECTS: A total of 177 subjects with short stature were enrolled. Of these, 151 were included in the intent to treat (AllITT) population, and 108 in the per protocol (AllPP) population. Analysis of ISS subjects included 126 children in the ITT (ISSITT) population and 68 subjects in the PP (ISSPP) population. MAIN OUTCOME MEASURES: We measured FH sd score (SDS), difference in SDS to midparenteral height (diff MPHSDS), and gain in heightSDS. RESULTS: After 5.9+/-1.1 yr on GH therapy, the FHSDS in the AllPP population treated with GH vs. controls was -1.5+/-0.81 (33 microg/kg.d, -1.7+/-0.70; and 67 microg/kg.d, -1.4+/-0.86; P<0.032), vs. -2.4+/-0.85 (P<0.001); the diff MPHSDS was -0.2+/-1.0 vs. -1.0+/-0.74 (P<0.001); and the gain in heightSDS was 1.3+/-0.78 vs. 0.2+/-0.69 (P<0.001). GH therapy was safe and had no impact on time to onset of puberty. A dose-response relationship identified after 1 yr remained to FH for all growth outcome variables in all four populations. CONCLUSION: GH treatment significantly increased FH in ISS children in a dose-dependent manner, with a mean gain of 1.3 SDS (8 cm) and a broad range of response from no gain to 3 SDS compared to a mean gain of 0.2 SDS in the untreated controls.

Treating fetal thyroid and adrenal disorders through the mother.

Advances in imaging techniques and in molecular diagnosis have enabled the identification in the fetus of disorders of thyroid and adrenal function that can potentially be treated in utero through the mother. In women with Graves disease, the rare instances of autoimmune fetal hyperthyroidism can generally be treated in a noninvasive way by optimizing treatment of the mother. For fetal hypothyroidism with goiter leading to hydramnios, repeated intra-amniotic injections of thyroxine have been reported to decrease the size of the fetal thyroid, but experience is limited and the risk of premature labor is raised. In women who have previously borne a child with severe congenital adrenal hyperplasia, attempts to prevent virilization of the external genitalia of further affected female fetuses involves treatment with high doses of dexamethasone from week 7 of gestation to term, which includes the crucial period of organogenesis. Only one of every eight fetuses treated will, however, benefit from this therapy, meaning that seven are unnecessarily exposed to this potentially harmful agent. In this article, we review the rationale and evidence for efficacy of these approaches, and discuss their potential adverse effects as well as the ethical problems that they raise.

Cognitive functions in children at risk for congenital adrenal hyperplasia treated prenatally with dexamethasone.

CONTEXT AND OBJECTIVE: In Sweden, from 1985 through 1995, 40 fetuses at risk for congenital adrenal hyperplasia (CAH) were treated with dexamethasone (DEX) to prevent virilization of affected females. We report long-term effects on neuropsychological functions and scholastic performance of this controversial treatment. DESIGN AND PATIENTS: Prenatally treated children, 7 to 17 yr old, were assessed with standardized neuropsychological tests (A Developmental Neuropsychological Assessment and Wechsler Intelligence Scales for Children) and child-completed questionnaires measuring self-perceived scholastic competence (Self-Perception Profile for Children). A parent-completed questionnaire (Child Behavior Checklist/4-18 School Scale) was used to evaluate whether the treatment had any impact on the children's school performance. In addition, a child-completed questionnaire measuring social anxiety (The Social Anxiety Scale for Children-Revised) was completed by the prenatally treated children aged 8 to 17 yr (n = 21) and age- and sex-matched controls (n = 26). RESULTS: Of 40 DEX-treated children, 26 (median age, 11 yr) participated in the study. Thirty-five sex- and age-matched healthy children were controls. There were no between-group differences concerning psychometric intelligence, measures of cerebral lateralization, memory encoding, and long-term memory. Short-term treated, CAH-unaffected children performed poorer than the control group on a test assessing verbal working memory (P = 0.003), and they rated lower on a questionnaire assessing self-perception of scholastic competence (P = 0.003). This group also showed increased self-rated social anxiety assessed by The Social Anxiety Scale for Children-Revised (P = 0.026). Prenatally treated, CAH-affected children performed poorer than controls on tests measuring verbal processing speed, although this difference disappeared when controlling for the child's full-scale IQ. CONCLUSIONS: This study indicates that prenatal DEX treatment is associated with previously not described long-term effects on verbal working memory and on certain aspects of self-perception that could be related to poorer verbal working memory. These findings may thus question future DEX treatment of congenital adrenal hyperplasia. Therefore, we encourage additional retrospective studies of larger cohorts to either confirm or challenge the present findings.

Very long-term follow-up of girls with early and late menarche.

Short- and long-term psychosocial effects of precocious or early normal puberty are probably more important for individuals than the moderate losses in final height they experience. Despite this, pediatric endocrinologists have focused much more on final height than psychosocial outcomes. As a surrogate for long-term follow-up studies of girls with precocious puberty, we have reviewed the results of a very long-term study of physical and psychosocial development of girls with normal early puberty. Results revealed that at age 15-16, girls with menarche before age 11 (early) were more norm-breaking, including being delinquents. In addition, they had earlier advanced sexual experiences. By adult age, there were no differences in psychosocial adjustment between the early- and late-developed women. Thus, the effects of early pubertal timing for psychosocial problems seem to be adolescent-limited. At ages 27 and 43, early-developed women had lower academic education. Regarding somatic development, at age 43, women with early menarche were shorter and heavier, had worse physical fitness and dieted more frequently compared to other women. There was no difference in quality of life. In searching for reasons for the antisocial behaviors in adolescence and the lower educational levels among early developers, early heterosexual relations seem to be the most crucial.

Raloxifene acts as an estrogen agonist on the rabbit growth plate.

Estrogen treatment has been used to induce growth plate fusion, thereby reducing the final height in girls expected to achieve extreme tall stature. The treatment is effective, in terms of limiting final height, but concerns have been raised that it might also increase the risk for malignancies later in life. Raloxifene, a selective estrogen receptor modulator, has been shown to act as an estrogen agonist on bone density but as an estrogen antagonist on breast and uterine tissue. The effect of raloxifene treatment on growth plate fusion and final height is unknown. The aim of this study was to determine whether raloxifene would act as an estrogen agonist or antagonist on growth plate cartilage. Ovariectomized immature rabbits were treated for 4 wk with vehicle (controls), estradiol cypionate (E2), or raloxifene. Tibial growth velocity was decreased in both E2- (P < 0.001) and raloxifene-treated animals (P < 0.001), compared with controls. E2 and raloxifene treatment also decreased chondrocyte proliferation and the height of the proximal tibial growth plate. In addition, E2 and raloxifene hastened fusion of the distal tibial growth plate (P < 0.05) and decreased the number of proliferative and hypertrophic chondrocytes per column in the proximal tibial growth plate. As expected, the uterus was enlarged by estrogen, but not raloxifene, treatment. We conclude that raloxifene acts as an estrogen agonist on the growth plate, accelerating growth plate senescence and thus hastening epiphyseal fusion.

The role of bilateral adrenalectomy in the treatment of congenital adrenal hyperplasia.

This report summarizes follow-up studies in 18 patients who underwent bilateral adrenalectomy for congenital adrenal hyperplasia. Three of these patients were young children with null/null mutations of CYP21, and the other 15 were adrenalectomized because of difficulties in their management on conventional therapy. The average duration of follow-up was 59 months and represents an aggregate of 90 postoperative years. The adrenals were removed laparoscopically in 13 patients and by open flank incisions in five. Adrenal crises associated with severe illnesses occurred in five patients at times when their glucocorticoid substitution was suboptimal. All were responsive to appropriate therapy. Two of these patients were young children who had hypoglycemia during gastroenteritis or febrile illness associated with poor food intake or vomiting. Significant elevations of adrenal steroid precursors, presumably from ectopic adrenal rests, were observed postoperatively in eight of the patients. Patients and parents were nearly unanimous in their enthusiasm for adrenalectomy. In most, signs of androgen excess have decreased, and obesity has become less of a problem with lowering the dose of glucocorticoid. We conclude that adrenalectomy is a safe and efficacious method of managing congenital adrenal hyperplasia in selected patients. Prophylactic adrenalectomy in young children with double null mutations remains experimental.

An androgen receptor gene mutation (E653K) in a family with congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency as well as in partial androgen insensitivity.

An androgen receptor (AR) variant (E653K) was found in two unrelated Swedish families. One family had two girls affected with congenital adrenal hyperplasia (CAH) due to steroid 21-hydroxylase deficiency. The girls, who showed mild virilization in relation to their CYP21 genotype, had inherited the AR gene mutation from their father, who showed no symptoms of androgen insensitivity. The other family had a boy with partial androgen insensitivity and ambiguous genitalia, and he had inherited the AR gene mutation from his mother. The mutant receptor showed a transactivating capacity in the same range as the normal receptor at high concentrations of ligand (1 and 10 nM dihydrotestosterone), but absent or reduced transactivation at low levels (0.01 and 0.1 nM). The receptor variant was not found among 250 additional unselected Swedish men. Sequencing of the AR gene in five unrelated CAH girls with the I172N mutation in CYP21 and minimal virilization did not reveal any additional deviations from the normal reference sequence. In addition, there was no difference in lengths of the polymorphic CAG repeat in the AR gene between CAH girls with the I172N mutation who showed minimal and severe virilization, and we found no evidence of skewed X-inactivation. We conclude that AR gene mutations or polymorphisms are not a common factor influencing the degree of hyperandrogenic symptoms displayed by CAH girls, and that the AR E653K mutation is compatible with normal genital development, although it can cause genital malformations in susceptible individuals.

Partial androgen insensitivity with phenotypic variation caused by androgen receptor mutations that disrupt activation function 2 and the NH(2)- and carboxyl-terminal interaction.

Partial androgen insensitivity with sex phenotype variation in two unrelated families was associated with missense mutations in the androgen receptor (AR) gene that disrupted the AR NH(2)-terminal/carboxy terminal interaction. Each mutation caused a single amino acid change within the region of the ligand-binding domain that forms activation function 2 (AF2). In one family, the mutation I737T was in alpha helix 4 and in the other F725L was between helices 3 and 4. Neither mutation altered androgen binding as determined by assays of mutant AR in the patient's cultured genital skin fibroblasts or of recombinant mutant receptors transfected into COS cells. In transient cotransfection assays in CV1 cells, transactivation with the AR mutants at low concentrations of DHT was reduced several fold compared with wild-type AR but increased at higher concentrations. Defects in NH(2)-terminal/carboxy terminal interactions were identified in mammalian two hybrid assays. In similar assays, there was reduced binding of the p160 coactivators TIF2/SRC2 and SRC1 to the mutant AR ligand binding domains (LBD). In the family with AR I737T, sex phenotype varied from severely defective masculinization in the proband to a maternal great uncle whose only manifestation of AIS was severe gynecomastia. He was fertile and passed the mutation to two daughters. The proband of the F725L family was also incompletely masculinized but was raised as a male while his half-sibling by a different father was affected more severely and reared as a female. These studies indicate that the function of an AR AF2 mutant in male development can vary greatly depending on the genetic background.

Prenatal treatment of congenital adrenal hyperplasia.

In foetuses at risk of virilising congenital adrenal hyperplasia (CAH), prenatal treatment can be offered by administration of dexamethasone (DEX) via the mother, in order to suppress foetal adrenal androgen oversecretion and prevent genital malformations. The first treated cases were described 20 years ago, and several hundred pregnancies have been reported since. There is a consensus that the treatment effectively prevents or reduces virilisation, but opinions regarding its safety differ. Rare adverse events have been reported in treated children, but no harmful effect has been documented that can be clearly attributed to the treatment. However, few treated foetuses have been followed until adolescence. Animal studies and epidemiological data point to various adverse effects of excess glucocorticoids on the developing foetus. In order to prevent virilisation effectively in females affected with CAH, the prenatal treatment needs to be instituted in the early first trimester, before prenatal diagnosis is possible. Thus, a majority of treated foetuses will receive DEX unnecessarily. The PREDEX study was initiated in Stockholm in 1999 as an open, controlled, non-randomised, multicentre trial. Participating centres are Stockholm, Bergen, Kuopio, Warsaw, London, Lyon and Barcelona. The study has been approved by the ethics committees in each country. The purpose of PREDEX is to evaluate prospectively the prenatal treatment regarding efficacy in preventing virilisation as well as to study its safety for both mothers and treated children. Children are followed until 18 years of age and a wide range of physiological, metabolic and developmental parameters are considered. In Sweden, treatment is not offered outside the frames of the trial.

Growth of spontaneously descended and surgically treated testes during early childhood.

OBJECTIVE: To investigate whether in congenital unilateral cryptorchidism the growth of a spontaneously descended testis is normal, compared with the contralateral scrotal testis or similar to the growth of testes that failed to descend spontaneously and later underwent orchidopexy. METHODS: Ninety-one boys with congenital unilateral cryptorchidism with later spontaneous descent of the initially retained testis were followed from birth (0-3 weeks) up to 5 years of age and compared with boys randomized to surgery at either 9 months (n = 78) or 3 years (n = 85) of age. Testicular volume was determined with ultrasonography. RESULTS: Eighty-two percent of spontaneous descent occurred before 2 months of age. Twenty-two percent of these descended testes were later again found in a retained position. The spontaneously descended testis was smaller than its scrotal counterpart at all ages (P < .001). We also showed a significant difference in the testicular volume between the early and late treated boys from age 2 years and onward. At 2, 4, and 5 years of age, the volumes of the spontaneously descended testes were significantly larger than those of boys operated on at 3 years but similar to those operated on at 9 months. CONCLUSIONS: We have shown that in boys with congenital unilateral cryptorchidism with later spontaneous descent, the originally retained testes show impaired growth compared with its scrotal counterpart from birth and onwards. Also, they are prone to later ascent to a retained position. Furthermore, the longer testes remain untreated the more they exhibit impaired growth.

Insulin-like growth factor-I and insulin-like growth factor binding protein-3 cotreatment versus insulin-like growth factor-I alone in two brothers with growth hormone insensitivity syndrome: effects on insulin sensitivity, body composition and linear growth.

BACKGROUND/AIMS: Growth hormone insensitivity syndrome (GHIS) is caused by a defective growth hormone receptor (GHR) and is associated with insulin-like growth factor-I (IGF-I) deficiency, severely short stature and, from adolescence, fasting hyperglycemia and obesity. We studied the effects of treatment with IGF-I in either a 1:1 molar complex with IGFBP-3 (IGF-I/BP-3-Tx) or with IGF-I alone (IGF-I-Tx) on metabolism and linear growth. METHODS: Two brothers, compound heterozygous for a GHR gene defect, were studied. After 8 months without treatment, we examined the short- and long-term effects of IGF-I/BP-3-Tx and, subsequently, IGF-I-Tx on 12-hour overnight levels of IGF-I, GH, insulin, IGFBP-1, insulin sensitivity by hyperinsulinemic euglycemic clamp, body composition by dual-energy X-ray absorptiometry and linear growth. RESULTS: Mean overnight levels of insulin decreased and IGFBP-1, a measure of hepatic insulin sensitivity, increased on both regimens, but was more pronounced on IGF-I-Tx. Insulin sensitivity by clamp showed no consistent changes. Lean body mass increased and abdominal fat mass decreased in both subjects on IGF-I-Tx. However, the changes were inconsistent during IGF-I/BP-3-Tx. Height velocity was low without treatment, increased slightly on IGF-I/BP-3-Tx and doubled on IGF-I-Tx. CONCLUSION: Both modalities of IGF-I improved determinants of hepatic insulin sensitivity, body composition and linear growth rate; however, IGF-I alone seemed to be more efficient.

Does growth hormone treatment influence pubertal development in short children?

AIM: To study the influence of growth hormone (GH) treatment on the initiation and progression of puberty in short children. METHODS: This prospective, randomized, controlled study included 124 short children (33 girls) who received GH treatment (Genotropin®; Pfizer Inc.) from a mean age of 11 years until near adult height [intent-to-treat (ITT) population]. Children were randomized into three groups: controls (n = 33), GH 33 µg/kg/day (n = 34) or GH 67 µg/kg/day (n = 57). Prepubertal children at study start constituted the per-protocol (PP) population (n = 101). Auxological measurements were made and puberty was staged every 3 months. Serum sex-steroid concentrations were assessed every 6 months. RESULTS: No significant differences were found between the groups, of both PP and ITT populations, in time elapsed from start of treatment until either onset of puberty, age at start of puberty or age at final pubertal maturation in either sex. In the ITT population, pubertal duration was significantly longer in GH-treated girls, and maximum mean testicular volume was significantly greater in GH-treated boys than controls, but there were no differences in testosterone levels between the groups. CONCLUSION: GH treatment did not influence age at onset of puberty and did not accelerate pubertal development. In boys, GH treatment appeared to increase testicular volume.

Undescended testes: a consensus on management.

The mode of treatment best for undescended testes is controversial, and local traditions often override knowledge gained from randomized controlled studies. In order to reach a consensus within the Nordic countries on the current state-of-the-art of treatment, a group of specialists in testicular physiology, paediatric surgery/urology, endocrinology, andrology, pathology and anaesthesiology from all the Nordic countries met for 2 days. Before the meeting, reviews of the literature had been prepared by the participants. Judging from published meta-analyses, hormonal treatment has low efficacy. Although 15-20% of retained testes descend during hormonal treatment, one-fifth of these re-ascend later on. Also, treatment with human chorionic gonadotropin (hCG) may be harmful to future spermatogenesis through increased apoptosis of germ cells. Orchiopexy, on the contrary, results in about 95% anatomical success, with a low (about 1%) risk of complications. The optimal time for orchiopexy has also been debated. However, a recent randomized controlled study shows that surgery at 9 months of age is followed by a better post-operative growth of the testes than surgery at 3 years, which supports previous arguments for early surgery. The unanimous conclusion of the group was that surgery is generally the preferred mode of treatment, rather than hCG or GnRH treatments. Orchiopexy should be performed between 6 and 12 months of age, or soon after diagnosis, if that occurs later. If a testis is found to be undescended at any age after 6 months, the patient should be referred for surgery. Referral should be to paediatric rather than general surgeons/urologists if the boy is less than 1 year old, if he has bilateral or non-palpable testes, or if he has got relapse of cryptorchidism.

Long-term follow-up of prenatally treated children at risk for congenital adrenal hyperplasia: does dexamethasone cause behavioural problems?

OBJECTIVES: To investigate the long-term effects of prenatal treatment of congenital adrenal hyperplasia (CAH) with emphasis on behavioural problems and temperament. DESIGN: A population-based long-term follow-up study of Swedish children at risk for virilising CAH, who had received treatment prenatally with dexamethasone (DEX). The questionnaire-based follow-up was performed when the children had reached school age. METHODS: Standardised parent-completed questionnaires were used to evaluate adaptive functioning, behavioural/emotional problems and psychopathology, social anxiety and temperament in DEX-exposed school-aged children (n=26) and matched controls (n=35). In addition, the association between parental questionnaires and children's self-ratings was investigated. RESULTS: There were no statistically significant differences between DEX-exposed children and controls in measures of psychopathology, behavioural problems and adaptive functioning. In a questionnaire on temperamental traits, DEX-exposed children were described by their parents as being more sociable than controls (P=0.042). The correlation analysis showed only modest parent-child agreement on social anxiety, i.e. the increased social anxiety in children's self-ratings was not confirmed by their parents. CONCLUSIONS: DEX-treated children showed good overall adjustment. The parent-child agreement with respect to social anxiety was modest, highlighting the importance of multiple information sources and assessment methods. The clinical significance of the observed difference in sociability cannot be determined within the frameworks of this study. Additional studies of larger cohorts are essential to make more decisive conclusions on the safety of the treatment. Until then, it is important that parents are thoroughly informed about the benefits and potential risks and uncertainties of this controversial treatment.

Surgical treatment of unilaterally undescended testes: testicular growth after randomization to orchiopexy at age 9 months or 3 years.

PURPOSE: We compared the growth of congenital, unilaterally undescended testes following orchiopexy at age 9 months or 3 years. MATERIALS AND METHODS: Patients were randomized to surgery at age 9 months (72) or 3 years (83). Testicular volume was measured by ultrasonography at ages 6, 12, 24, 39 and 48 months. RESULTS: Orchiopexy at age 9 months resulted in an increase in testicular volume at subsequent measurements at ages 2, 3 and 4 years compared to the volume at 6 months (p <0.001). In contrast, no significant growth was noted in the group treated at age 3 years. The improved testicular growth after early orchiopexy was also demonstrated by a gradual increase in the ratio of the previously retained testis and the scrotal testis in individual boys from 6 months to 4 years (0.68 to 0.81, p <0.001). For the late treatment group a significant decrease in this ratio was noted during the same period (0.68 to 0.56, p <0.01). CONCLUSIONS: Surgical treatment at 9 months resulted in partial catch-up of testicular growth until at least age 4 years compared to surgery at 3 years, clearly indicating that early surgery has a beneficial effect on testicular growth. Since testicular volume is an approximate indirect measure of spermatogenic activity, this gives hope that orchiopexy at this age may improve future spermatogenesis.

Development and descent of the testis in relation to cryptorchidism.

UNLABELLED: The testis descends in two phases. Animal studies suggest, that the transabdominal descent of the testis depends on the insulin-like hormone 3 (INSL3). Androgens are important in the inguinoscrotal testicular descent in animals and humans. In general, the cause of cryptorchidism is unknown and the aetiology is possibly multifactorial. Histological changes in cryptorchid testes demonstrate disturbed development. CONCLUSION: Since testicular descent is regulated by testis-derived hormones, cryptorchidism may reflect a functional defect of the testis.