Overview

Definition

Cryptorchidism is the absence of 1 or both testicles Testicles The testicles, also known as the testes or the male gonads, are a pair of egg-shaped glands suspended within the scrotum. The testicles have multiple layers: an outer tunica vaginalis, an intermediate tunica albuginea, and an innermost tunica vasculosa. The testicles are composed of testicular lobules and seminiferous tubules. Testicles in the scrotum. Cryptorchid testis (“hidden testis”) may be undescended or absent (atrophied).

Epidemiology

• Prevalence at birth about 3% overall: 
  • Full-term infants: 2%–5%  
  • Premature infants: 30% 
• Risk factors:
  • Maternal smoking and alcohol exposure 
  • Fetal exposure to paracetamol/ acetaminophen Acetaminophen Acetaminophen is an over-the-counter nonopioid analgesic and antipyretic medication and the most commonly used analgesic worldwide. Despite the widespread use of acetaminophen, its mechanism of action is not entirely understood. Acetaminophen and diethylstilbestrol  
  • Prematurity 
  • Small for gestational age and low birth weight
• Cryptorchidism is usually an isolated condition, but there are related disorders:
  • Disorders of sexual differentiation (DSD) 
  • Congenital adrenal hyperplasia Congenital adrenal hyperplasia Congenital adrenal hyperplasia (CAH) consists of a group of autosomal recessive disorders that cause a deficiency of an enzyme needed in cortisol, aldosterone, and androgen synthesis. The most common subform of CAH is 21-hydroxylase deficiency, followed by 11β-hydroxylase deficiency. Congenital Adrenal Hyperplasia (CAH) 
  • Genetic disorders such as Klinefelter syndrome Klinefelter syndrome Klinefelter syndrome is a chromosomal aneuploidy characterized by the presence of 1 or more extra X chromosomes in a male karyotype, most commonly leading to karyotype 47,XXY. Klinefelter syndrome is associated with decreased levels of testosterone and is the most common cause of congenital hypogonadism. Klinefelter Syndrome and Prader-Willi syndrome Prader-Willi syndrome Prader-Willi syndrome (PWS) is a rare autosomal neurodevelopmental genetic disorders mapped to a specific region of chromosome 15 attributed to genomic imprinting. A paternally derived chromosome 15 with this deletion results in 15q11-13 paternal deletion syndrome, or PWS. Prader-Willi Syndrome and Angelman Syndrome

Pathophysiology

Pathogenesis overall is not well understood but is affected by hormonal and anatomical embryologic factors.

Normal mechanical descent:

• Intra-abdominal phase: mediated by the hormone descendin
• Inguinal phase (by the 28th week of gestation): mediated by androgen/testosterone 
• Gubernaculum swells and pulls the testis down into the scrotum along the inguinal canal Inguinal canal The inguinal region, or the groin, is located in the RLQ and LLQ of the anterior abdominal wall, bordered by the thigh inferiorly, the pubis medially, and the iliac crest superolaterally. The inguinal canal is a tubular structure that runs in a straight line from the anterior superior iliac spine to the pubic tubercle. Inguinal Canal and Hernias. 

Defective mechanisms in the different phases of descent:

• Alterations in hypothalamic-pituitary-adrenal (HPA) axis, especially testosterone 
• In utero, increased expression of estradiol in the placenta Placenta The placenta consists of a fetal side and a maternal side, and it provides a vascular communication between the mother and the fetus. This communication allows the mother to provide nutrients to the fetus and allows for removal of waste products from fetal blood. Placenta, Umbilical Cord, and Amniotic Cavity 
• Testicular agenesis (from vascular compromise, causing absent testis)
• Changes in abdominal pressure

Clinical Presentation and Diagnosis

Clinical findings

• Palpable: 
  • Suprascrotal (most common location): outside the external inguinal ring 
  • Intracanalicular: inguinal canal Inguinal canal The inguinal region, or the groin, is located in the RLQ and LLQ of the anterior abdominal wall, bordered by the thigh inferiorly, the pubis medially, and the iliac crest superolaterally. The inguinal canal is a tubular structure that runs in a straight line from the anterior superior iliac spine to the pubic tubercle. Inguinal Canal and Hernias 
• Non-palpable:
  • Intra-abdominal 
  • Absent testis 
  • Empty or hypoplastic scrotum

Examination

• Diagnosis is mainly based on a comprehensive physical examination.
  • Testicular exam:
    • Position infant in the supine position.
    • Exam requires warm lubricated hands: 1 hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand near the anterior superior iliac spine (ASIS) and the other on the scrotum
    • Use fingertips to sweep from ASIS along the inguinal canal Inguinal canal The inguinal region, or the groin, is located in the RLQ and LLQ of the anterior abdominal wall, bordered by the thigh inferiorly, the pubis medially, and the iliac crest superolaterally. The inguinal canal is a tubular structure that runs in a straight line from the anterior superior iliac spine to the pubic tubercle. Inguinal Canal and Hernias.
  • Genital exam:
    • Assess position of urethral meatus to rule out hypospadias.
    • Check phallus for size and atypical appearance. 
    • Look for hypoplastic scrotum or poorly rugated scrotal skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Structure and Function of the Skin. 
  • Inguinal exam: Assess for fullness; may indicate hernia or lymphadenopathy Lymphadenopathy Lymphadenopathy is lymph node enlargement (> 1 cm) and is benign and self-limited in most patients. Etiologies include malignancy, infection, and autoimmune disorders, as well as iatrogenic causes such as the use of certain medications. Generalized lymphadenopathy often indicates underlying systemic disease. Lymphadenopathy.
• Imaging:
  • Generally not necessary as it lacks sensitivity or specificity on treatment decision
  • Ultrasound: may be indicated when ruling out disorder of sexual differentiation or gonads/uterus 

Management

Treatment principles

• Goal: Fix the viable undescended testis in the normal scrotal position or remove nonviable testicular elements.
• Timing: 
  • No spontaneous descent by 6 months of age triggers the need for intervention.
  • Surgery before 2 years of age (ideally before 1 year) 
• Treatment is recommended to:
  • Allow testicular growth and for fertility preservation
  • Reduce the risk of testicular cancer Testicular cancer Testicular cancer is the most common solid malignancy affecting men 15-35 years of age. Most of the testicular cancers are of the germ cell tumor type, and they can be classified as seminomas and nonseminomas. The most common presentation of testicular cancer is a painless testicular mass. Testicular Cancer
  • Allow for detection of testicular masses
  • Decrease the risk of testicular torsion Testicular torsion Testicular torsion is the sudden rotation of the testicle, specifically the spermatic cord, around its axis in the inguinal canal or below. The acute rotation results in compromised blood flow to and from the testicle, which puts the testicle at risk for necrosis. Testicular Torsion

Surgery for palpable testis

• Orchiopexy via inguinal approach: Testis and spermatic cord are released from attachments and the testis is sutured in the scrotum. 
• Complications: testicular atrophy, infection, bleeding, inguinal hernia

Surgery for nonpalpable testis

• Diagnostic laparoscopy Laparoscopy Laparoscopy is surgical exploration and interventions performed through small incisions with a camera and long instruments. Laparotomy and Laparoscopy to search for intra-abdominal testis
• If no testis is found, must determine presence of blind-ending vessels or testicular nubbin.
• If testis is found, can proceed with laparoscopic orchiopexy (options):
  • Single-stage orchiopexy without division of gonadal vessels 
  • 1-stage Fowler-Stephens (FS) orchiopexy with gonadal vessels divided
  • 2-stage FS orchiopexy where the gonadal vessels are clipped to allow collateral blood flow to testis in 6 months to mobilize testis

Clinical Relevance

• Testicular cancer: Patients with a history of cryptorchidism have an increased risk of testicular cancer Testicular cancer Testicular cancer is the most common solid malignancy affecting men 15-35 years of age. Most of the testicular cancers are of the germ cell tumor type, and they can be classified as seminomas and nonseminomas. The most common presentation of testicular cancer is a painless testicular mass. Testicular Cancer (relative risk of 2.9). The most common presentation is a painless testicular nodule. Most of the testicular cancers are germ cell tumors. Diagnosis involves physical exam, testicular ultrasound, serum tumor markers Serum Tumor Markers Serum tumor markers are proteins or carbohydrates produced by cancer cells that are associated with a malignancy of a specific origin (e.g., thyroglobulin in thyroid cancer). Genetic changes in a malignancy, such as gene mutations or patterns of gene expression, are also being used as tumor markers, and are often referred to as "cellular tumor markers." Serum Tumor Markers, and metastatic workup. Treatment is radical orchiectomy.  
• Testicular torsion: the most common cause of acute testicular and scrotal emergency pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain. Patients have unilateral testicular pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain, most frequently caused by a high abnormal attachment of the tunica vaginalis, making it prone to twisting. Scrotal ultrasound is helpful, but testicular torsion Testicular torsion Testicular torsion is the sudden rotation of the testicle, specifically the spermatic cord, around its axis in the inguinal canal or below. The acute rotation results in compromised blood flow to and from the testicle, which puts the testicle at risk for necrosis. Testicular Torsion is mostly a clinical diagnosis and requires immediate scrotal exploration and orchiopexy. 
• Inguinal canal and hernias: hernia occurs in parts of the abdominal wall where the musculature is not continuous. The increased pressure in the abdominal cavity leads to an evagination (protrusion) of the parietal peritoneum Peritoneum The peritoneum is a serous membrane lining the abdominopelvic cavity. This lining is formed by connective tissue and originates from the mesoderm. The membrane lines both the abdominal walls (as parietal peritoneum) and all of the visceral organs (as visceral peritoneum). Peritoneum and Retroperitoneum and parts of organs through the surrounding muscles (in this case, the inguinal canal Inguinal canal The inguinal region, or the groin, is located in the RLQ and LLQ of the anterior abdominal wall, bordered by the thigh inferiorly, the pubis medially, and the iliac crest superolaterally. The inguinal canal is a tubular structure that runs in a straight line from the anterior superior iliac spine to the pubic tubercle. Inguinal Canal and Hernias). Diagnosis is made by physical exam and ultrasound, with manual reduction or hernia repair as necessary. 
• Infertility Infertility Infertility is the inability to conceive in the context of regular intercourse. The most common causes of infertility in women are related to ovulatory dysfunction or tubal obstruction, whereas, in men, abnormal sperm is a common cause. Infertility: A history of cryptorchidism will increase the incidence of impaired spermatogenesis and lower fertility rates. Studies show that early orchiopexy and diagnosis of undescended testis will lead to increased fertility preservation. 
• Retractile testis: when the testicles Testicles The testicles, also known as the testes or the male gonads, are a pair of egg-shaped glands suspended within the scrotum. The testicles have multiple layers: an outer tunica vaginalis, an intermediate tunica albuginea, and an innermost tunica vasculosa. The testicles are composed of testicular lobules and seminiferous tubules. Testicles are palpable but in an extra-scrotal position on examination and can be manipulated into the scrotum. The testicles Testicles The testicles, also known as the testes or the male gonads, are a pair of egg-shaped glands suspended within the scrotum. The testicles have multiple layers: an outer tunica vaginalis, an intermediate tunica albuginea, and an innermost tunica vasculosa. The testicles are composed of testicular lobules and seminiferous tubules. Testicles will remain in a dependent scrotal location temporarily and re-ascend. Treatment is with serial exams and monitoring of descent.