The pediatric physical examination: The perineum

INTRODUCTION — Examination of the perineum in children will be reviewed here. Other aspects of the pediatric physical examination are discussed separately.

●(See "The pediatric physical examination: General principles and standard measurements".)

●(See "The pediatric physical examination: HEENT".)

●(See "The pediatric physical examination: Back, extremities, nervous system, skin, and lymph nodes".)

●(See "The pediatric physical examination: Chest and abdomen".)

PREPARATION FOR EXAMINATION — The genitourinary examination may be uncomfortable for children and adolescents. Children who have been warned by parents or caregivers, teachers, or guardians not to allow anyone to see or touch their private areas without permission may be apprehensive and uncooperative. Other children and adolescents may be apprehensive because they have a gender identity that differs from their external genitalia or have a history of sexual victimization, although they may not have disclosed this information. (See "Management and sequelae of sexual abuse in children and adolescents", section on 'Sexual abuse in health care settings'.)

The clinician should explain why the genitourinary examination is needed and describe how it will be performed, including what instruments, if any, will be used. Appropriate gowning and/or covering should be provided. The patient should be encouraged to ask questions and assert their choices about how and whether the examination should proceed. This patient-centered approach to the examination is discussed in detail separately. (See "Adolescent relationship abuse including physical and sexual teen dating violence", section on 'Patient-centered evaluation'.)

USE OF CHAPERONES

●Infants and children – The parent, caregiver, or guardian of an infant or child should be present during examination of the perineum unless their presence would interfere with the examination, in which case a chaperone should be present [1-3].

●Adolescents – The use of noncaregiver chaperones for adolescent patients is recommended; however, use of a chaperone should be a shared decision between the adolescent and the clinician after the clinician has explained the reason for the examination and described the examination process [1-3]. If possible, the adolescent should be permitted to choose the gender of the chaperone. If the adolescent declines the use of a chaperone, the declination should be documented in the medical record.

MALE GENITOURINARY SYSTEM

Neonates — The genitourinary examination in male neonates is focused on detection of congenital anomalies. The precipitation of uric acid crystals in the diaper secondary to increased urinary uric acid excretion (which is normal in infants) may be misidentified as blood (picture 1).

●Penis – Examination of the penis includes assessment of phallic size (figure 1), the foreskin, and the location of the urethral meatus. Assessment of phallic size in neonates is discussed separately. (See "Evaluation of the infant with atypical genital appearance (difference of sex development)", section on 'Clitorophallic size'.)

The foreskin is usually tightly adherent in the neonate (normal physiologic phimosis); it should be gently retracted to identify the urethral meatus. Forceful retraction is never indicated, particularly in the infant. Care of the uncircumcised penis is discussed separately. (See "Care and complications of the uncircumcised penis in infants and children", section on 'Routine care'.)

The urethral meatus is normally located at the tip of the glans penis. Hypospadias is diagnosed if the urethral meatus is found on the ventral surface proximal to the glans; a hooded foreskin and chordee generally are present (picture 2). Epispadias is diagnosed when the urethral meatus is found on the dorsal surface of the penis. Additional evaluation and management of infants with hypospadias are discussed separately. (See "Hypospadias: Pathogenesis, diagnosis, and evaluation".)

●Scrotum – Examination of the scrotum includes assessment of scrotal anatomy (including rugae), the presence and location of the testes, and other abnormalities (eg, hydrocele, hernia).

The development of scrotal rugae helps to determine the maturity of male neonates (table 1). The rugae are shallow and poorly developed in preterm infants and deep and fully developed in term infants. (See "Postnatal assessment of gestational age", section on 'New Ballard score'.)

The examiner assesses the presence and position of the testicles through palpation with the index and/or middle finger placed behind the scrotum and the thumb in front of it. If the scrotal sac is empty (picture 3), each inguinal canal should be examined for retained testicular tissue. The neonate should be in a supine position. With the index and middle finger of the examining hand positioned over the inguinal canal, the examiner should palpate the length of the canal and attempt to gently express any retained testicular tissue into the scrotum. At the same time, the middle finger, index finger, and thumb of the opposite hand should be properly positioned to palpate the ipsilateral proximal scrotum for any testicular tissue entering from the inguinal canal. (See "Undescended testes (cryptorchidism) in children: Clinical features and evaluation", section on 'Examination'.)

The scrotum should be reexamined at each well child visit, even if previous examinations have revealed testes palpable in the scrotum. Some males have palpable testes in the scrotum on one visit, but months to years later the examination reveals that the testes have spontaneously ascended into the inguinal canal or into an intra-abdominal position [4]. The evaluation and treatment of undescended testes is discussed separately. (See "Undescended testes (cryptorchidism) in children: Management", section on 'Management of undescended testes'.)

Palpation of the scrotum may reveal unilateral or bilateral fullness in addition to the normally palpable testis. Transillumination of the area using a narrow-beam, bright light source frequently reveals either a fluid-filled hydrocele or an indirect inguinal hernia. Hydroceles generally spontaneously regress during the first 12 to 18 months of life. Occasionally, they are accompanied by hernias, sometimes making it difficult to distinguish between the two. Hernias usually fill the inguinal area and the upper two-thirds of the scrotum, whereas hydroceles may be confined to the scrotal area alone. (See "Inguinal hernia in children" and "Inguinal hernia in children", section on 'Differential diagnosis'.)

●Inguinal area – The inguinal area should be palpated for masses (eg, inguinal hernia). (See "Inguinal hernia in children".)

Older infants and preschoolers

●Scrotum and testicles – Palpation of the scrotum is necessary to determine the position of the testicles. If palpation is difficult, the child can be placed in a sitting knee-chest position to help force the testes into a dependent position. Other maneuvers to facilitate palpation of the testes are discussed separately. (See "Undescended testes (cryptorchidism) in children: Clinical features and evaluation", section on 'Examination of the testes and genitalia'.)

●Penis – Penile length should be grossly assessed; measurement of penile length is not necessary for routine physical examination. Penile length is rarely used for monitoring pubertal progress. Measurement of stretched penile length is discussed separately. (See "Normal puberty", section on 'Boys'.)

The foreskin of an uncircumcised penis may be difficult to retract. Fusion of the inner epithelium of the prepuce and the epithelium of the glans accounts for the nonretractability. In the first few years of life, squamous cells eventually keratinize, and the prepuce separates from the glans, allowing for normal retraction. (See "Care and complications of the uncircumcised penis in infants and children", section on 'Benign conditions'.)

Occasionally, the glans becomes traumatized or infected, producing erythema and swelling (balanitis). (See "Balanitis and balanoposthitis in children and adolescents: Clinical manifestations, evaluation, and diagnosis".)

Foreskin that has been forcibly retracted and not returned to its normal anatomic position may create a ligature around the penile shaft (paraphimosis) that requires immediate medicosurgical intervention. (See "Paraphimosis: Clinical manifestations, diagnosis, and treatment".)

Preadolescent and adolescent males — Examination of the genitourinary system in preadolescent and adolescent males includes evaluation of the testes, scrotum, penis, urethral meatus, and pubic hair. Accurate adolescent sexual maturity rating (SMR) in preadolescent and adolescent males is determined by assessing testicular and penile enlargement and the extent of pubic hair development (picture 4). (See "Normal puberty".)

The patient and/or patient's caregiver should be appropriately informed and counseled if any abnormal findings are identified. Normal findings also should be communicated to the patient, particularly those who were apprehensive during the examination.

●Testes and scrotum – As the male approaches puberty, at an average age of 11 to 12 years, the first sign of pubertal onset is testicular enlargement (SMR stage 2) (picture 4). (See "Normal puberty".)

Testicular length before puberty is normally 1.5 to 2 cm (table 2). Testicular length can be determined using a measuring tape or calipers; alternatively, testicular size and volume can be determined with the use of orchidometer beads (picture 5 and figure 2). When testicular growth is questionable, ultrasound measurements should be obtained [5]. The left testicle tends to be positioned lower in the scrotum.

The scrotum should be inspected for unusual lesions and palpated for testicular position, hernias, and abnormal masses (such as a varicocele [dilation of spermatic cord veins). The normal testicular surface feels smooth; an adjacent varicocele feels like a clump of worms. Most varicoceles collapse when the patient assumes a supine position. Adolescent varicoceles can be detected more frequently if the patient is examined while standing. (See "Sexually transmitted infections: Issues specific to adolescents", section on 'STI clinical patterns' and "Causes of painless scrotal swelling in children and adolescents", section on 'Varicocele'.)

Testicular self-examination is discussed separately. (See "Screening for testicular cancer", section on 'Limitations and potential harms of testicular examination'.)

●Penis – Penile enlargement begins in SMR stage 3 and continues through stage 5 (picture 4). Penile length should be grossly assessed; measurement of penile length is not necessary for routine physical examination. Penile length is rarely used for monitoring pubertal progress. Measurement of stretched penile length is discussed separately. (See "Normal puberty", section on 'Boys'.)

The examination of the penis also includes inspection of the skin for unusual lesions and the urethral meatus for discharge. (See "Sexually transmitted infections: Issues specific to adolescents", section on 'STI clinical patterns'.)

●Pubic hair development – Pubic hair becomes evident in SMR stage 2, at first long and straight and later curling (picture 4). By SMR stage 4, pubic hair becomes more abundant, spreading to involve the symphysis pubis and eventually the thighs. (See "Normal puberty".)

Delayed onset of male puberty generally is attributable to constitutional delay and warrants close follow-up. (See "Approach to the patient with delayed puberty".)

Pubic hair development without testicular enlargement is a common manifestation of premature adrenarche. (See "Premature adrenarche".)

FEMALE GENITOURINARY SYSTEM

Neonates — Genitourinary examination of female neonates and infants requires careful inspection of anatomic structures. Proper visualization should be done with the infant in a supine position, legs flexed and abducted at the hips.

In the female neonate, there is no visible distinction between the labia majora and labia minora. A unilateral soft tissue mass in the inguinal or labial areas may represent a direct inguinal hernia or, less commonly, palpable gonads (picture 6), indicating a difference of sex development. (See "Inguinal hernia in children" and "Evaluation of the infant with atypical genital appearance (difference of sex development)".)

Gentle separation of the labia reveals the clitoris, urethral meatus, and vaginal introitus from superior to inferior. Clitoral width in a typical XX neonate ranges from 2 to 6 mm. Mean clitoral length in the newborn infant may vary in different population groups, but lengths of more than 9 mm are unusual. The clitoris may appear disproportionately more prominent in preterm infants because clitoral size is fully developed by 27 weeks of gestation and because there is less fat in the labia. If the clitoris is large (picture 7A-B) and posterior labial fusion is noted, virilization secondary to congenital adrenal hyperplasia should be ruled out. (See "Evaluation of the infant with atypical genital appearance (difference of sex development)", section on 'Initial laboratory testing'.)

Patency of the vaginal introitus should be established by visual inspection. Many neonates have vaginal tags, which are of no significance and eventually spontaneously regress. In the first few days after birth, a transient, blood-tinged, mucoid vaginal discharge may be seen secondary to maternal estrogen withdrawal. The precipitation of uric acid crystals in the diaper secondary to increased urinary uric acid excretion may be misidentified as blood (picture 1), but increased urinary acid excretion is normal in infants.

Older infants and preschoolers — Female older infants and preschoolers are best examined in the supine position with the legs abducted at the hips. Gentle posterolateral retraction of the skin surrounding the inferior vulvar rim provides optimal visualization. The anatomy and physiology of the female genitourinary system in female toddlers and preschoolers are similar to those of neonates (figure 3). (See 'Neonates' above.)

Visualization of the vulvar anatomy may be obscured by labial adhesions, a thin tissue membrane adherent to labial skin that does not impede urinary flow (picture 8). The evaluation and management of labial adhesions are discussed separately. (See "Overview of vulvovaginal conditions in the prepubertal child", section on 'Labial adhesions'.)

Preadolescent and adolescent females — Genitourinary examination of preadolescent and adolescent females includes inspection of external genitalia and assessment of sexual maturity rating (SMR)/Tanner stage. Pelvic examination (speculum and/or bimanual) may also be necessary for some preadolescent and adolescent females.

The routine genitourinary examination of preadolescent and adolescent females is conducted with the legs in a frog-like position, flexed and abducted at knees and hips. An alternate position is with the patient prone in a knee-chest position (figure 4). Typically, this position is only utilized if visualization is limited in the frog-like position.

●Pubertal sequence – The first sign of puberty (SMR stage 2) for females generally is breast development (picture 9A), followed shortly thereafter by the growth of pubic hair (picture 9B). However, growth of pubic hair occurs first in some individuals. Early pubarche is a common clinical manifestation of adrenarche. (See "Physiology and clinical manifestations of normal adrenarche", section on 'Clinical manifestations of adrenarche' and "Premature adrenarche".)

The definitions of and evaluation for precocious puberty and delayed puberty are discussed separately. (See "Definition, etiology, and evaluation of precocious puberty" and "Approach to the patient with delayed puberty".)

●Vagina – The vaginal mucosa in the prepubertal adolescent is thin, moist, and somewhat red. The examiner should look for any signs of trauma, irritation, or discharge [6]. As puberty progresses, estrogen stimulation of the vaginal mucosa produces a thickened, dull-pink mucoid surface.

In early puberty, a normal watery, milky white, or clear, nonfoul-smelling vaginal discharge may be present (leukorrhea). The presence of blood, purulent discharge, or foul odor requires investigation. Evidence of trauma or blood should raise the possibility of sexual abuse. In the younger child with genital blood or foul odor, the examiner should consider the possibility of a vaginal foreign body. (See "Evaluation of sexual abuse in children and adolescents" and "Overview of vulvovaginal conditions in the prepubertal child", section on 'Vaginal foreign body'.)

Vaginal discharge in adolescents may indicate vaginitis or a sexually transmitted infection. Evaluation for these conditions are discussed separately. (See "Vaginitis in adults: Initial evaluation" and "Sexually transmitted infections: Issues specific to adolescents", section on 'Discharge syndromes'.)

●Clitoris – The clitoris should be assessed for enlargement. Although one review defined clitoromegaly as clitoral width >6 mm in females age 4 through 8 years, >5 mm in females 8 through 12 years, and >8 mm in those ≥13 years [7], observational studies note great variation in size and morphology of the external genitalia in female children [7-9].

Hormonal causes of clitoral enlargement include congenital adrenal hyperplasia and androgen-secreting tumors (ovarian or adrenal) in genotypic females [9]. The clinician must also consider the possibility of clitoris-like phallus in a genotypic male with a difference of sex development (eg, androgen insensitivity, 5-alpha-reductase deficiency). Nonhormonal causes of clitoral enlargement include neurofibromatosis, hemangioma, and epidermoid cyst. (See "Genetics and clinical manifestations of classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency", section on 'Atypical genitalia' and "Adrenal hyperandrogenism" and "Causes of differences of sex development".)

●Vulvar area – Inspection of the vulvar area may identify abnormalities or anatomic variations, including [10]:

•Prolapsed urethra, which appears as an edematous, violaceous, nontender, donut-shaped mass surrounding the urethral meatus (picture 10); bleeding from this area may be the presenting complaint [11-13] (see "Overview of vulvovaginal conditions in the prepubertal child", section on 'Urethral prolapse')

•Prolapsed ectopic ureterocele [14,15] (see "Ureterocele")

•Paraurethral cyst

•Anatomic variations of the hymen (figure 5), including imperforate hymen (which may lead to hydrocolpos or hydrometrocolpos)

•Sarcoma botryoides, a form of embryonal rhabdomyosarcoma that arises within the wall of the bladder or vagina, and has the appearance of a cluster of grapes (picture 11) (see "Rhabdomyosarcoma in childhood and adolescence: Epidemiology, pathology, and molecular pathogenesis", section on 'Embryonal RMS')

●Indications for pelvic examination – Internal examination (speculum and/or bimanual) of preadolescent and adolescent females generally is reserved for those with genitourinary complaints or suspected genitourinary pathology. Indications include [16]:

•Evaluation of acute abdominal and pelvic pain and tenderness (table 3) (see "Causes of acute abdominal pain in children and adolescents" and "Evaluation of acute pelvic pain in female children and adolescents", section on 'Physical examination')

•Evaluation of vaginal discharge if vaginal foreign body is suspected (eg, retained tampon or condom fragments)

•Suspected congenital anomalies (eg, vaginal cyst, vaginal septum) (see "Congenital anomalies of the hymen and vagina", section on 'Anomalies of the vagina')

•Suspected or reported sexual abuse (see "Evaluation of sexual abuse in children and adolescents", section on 'Female genitalia')

•Screening/testing for Neisseria gonorrhoeae or Chlamydia trachomatis, although urine testing or patient-collected vaginal swabs are effective and often preferred by adolescents (see "Screening for sexually transmitted infections", section on 'Screening methods')

•Evaluation of menstrual irregularities or gynecologic symptoms or concerns (eg, amenorrhea unrelated to pregnancy, prolonged or heavy menstrual bleeding, dysmenorrhea unresponsive to nonsteroidal anti-inflammatory drugs) (see "Abnormal uterine bleeding in adolescents: Evaluation and approach to diagnosis", section on 'Physical examination')

•Contraceptive counseling for an intrauterine device (see "Intrauterine contraception: Insertion and removal", section on 'Procedure')

•Pregnancy

●Pelvic examination procedure – The pelvic examination procedure, including patient preparation, equipment, and components, is discussed separately. (See "Gynecologic examination of the newborn and child", section on 'Evaluation of pelvic organs' and "The gynecologic history and pelvic examination", section on 'Pelvic examination'.)

ANUS AND RECTUM — Examination of the anus and rectum is relatively standard for all children and adolescents. Anatomic abnormalities are unusual, except for the rare finding of an imperforate anus or an anteriorly placed anus (figure 6).

●Inspection – The normal perianal area is an intact, symmetrically wrinkled area of pigmented skin. The perianal area should be examined for fissures, hemorrhoids, and other lesions that may require additional evaluation or management, including:

•Perianal fissures (picture 12), which may be caused by dry irritated skin or straining during defecation and passage of hard stools (see "Recent-onset constipation in infants and children")

•External hemorrhoids and prolapsed internal hemorrhoids, which are found primarily in older children and adolescents

•Condylomata acuminata (picture 13A-B) (see "Condylomata acuminata (anogenital warts) in children")

•Signs of perianal trauma (eg, bruises, lacerations), which may indicated sexual abuse (see "Evaluation of sexual abuse in children and adolescents", section on 'Perianal area')

•Skin tags (picture 14) or granulomatous lesions, which may indicate inflammatory bowel disease (see "Clinical manifestations and complications of inflammatory bowel disease in children and adolescents", section on 'Oral and perianal disease')

•Rectal prolapse (see "Rectal prolapse in children", section on 'Predisposing conditions')

•Infantile perianal pyramidal protrusion (IPPP)/infantile perineal protrusion [17-19]

IPPP is a nontender pedunculated protrusion with a tongue-like tip that is covered with smooth skin (picture 15) [17,18,20]. In lightly pigmented skin, the lesion may appear red or rose-colored. It is usually, though not always, pyramidal. IPPP is typically located in the midline, just anterior to the anus, although posterior lesions have been reported [21]. IPPP occurs almost exclusively in females and may be associated with constipation and/or lichen sclerosis [17-19,21,22].

Treatment generally is not necessary. The clinical course is one of recurrent swelling and eventual resolution. The clinical course and characteristic appearance distinguish IPPP from condyloma acuminata (picture 13A), trauma, skin tags, rectal prolapse, and granulomatous lesions of inflammatory bowel disease [20].

●Digital rectal examination – Digital rectal examinations are not performed routinely as part of the regular physical examination of children. When digital examination becomes necessary, the examiner should remain sensitive to the potential embarrassment and discomfort for the patient. The patient and/or guardian should be given an easily understandable explanation of why the examination is being done and what discomfort might be experienced. The examination is performed best with the patient lying on their left side and legs flexed at the hips and knees. Gloves and an appropriate lubricant should be used.

In the child with a lower abdominal mass and/or history of constipation or infrequent passage of stools, a rectal examination may help to make the diagnosis. A smooth-walled rectal vault with soft stool in the rectal ampulla is the normal finding. A palpable abnormal mass or blood-tinged stool on a gloved finger requires more extensive investigation. (See "Constipation in infants and children: Evaluation", section on 'Digital anorectal examination'.)

SUMMARY

●Preparation – The clinician should explain why the genitourinary examination is needed and describe how it will be performed. Appropriate gowning and/or covering should be provided. The patient should be encouraged to ask questions and assert their choices about how and whether the examination should proceed. (See 'Preparation for examination' above.)

●Use of chaperones – The parent, caregiver, or guardian of an infant or child should be present during examination of the perineum unless their presence would interfere with the examination, in which case a chaperone should be present. The use of chaperones for adolescent patients should be a shared decision between the adolescent and the clinician after the clinician has explained the reason for the examination and described the examination process. (See 'Use of chaperones' above.)

●Male genitourinary system

•The genitourinary examination of newborn male infants focuses on congenital anomalies, including microphallus (figure 1), abnormal location of the urethral meatus (picture 2), undescended testicles (picture 3), and abnormal scrotal or inguinal masses. (See 'Neonates' above.)

•In older male infants and preschoolers, important aspects of the examination include the position of the testicles, gross assessment of penile size, and retractability of the foreskin (if the male is uncircumcised). (See 'Older infants and preschoolers' above.)

•The evaluation of preadolescent and pubertal males includes assessment of sexual maturity rating (SMR)/Tanner stage (picture 4); evaluation for urethral discharge; and scrotal palpation for testicular position, hernias, and abnormal masses. (See 'Preadolescent and adolescent males' above.)

●Female genitourinary system

•The genitourinary examination of female neonates, infants, and preschoolers focuses on congenital anomalies including labial masses, clitoral enlargement (picture 7A-B), and visual patency of the vaginal introitus. (See 'Neonates' above and 'Older infants and preschoolers' above.)

•Genitourinary examination of preadolescent and adolescent females includes assessment of SMR (picture 9A-B) and inspection of the external genitalia for signs of vaginal trauma, irritation, or discharge; clitoral enlargement; and lesions of the vulvar area (eg, prolapsed urethra (picture 10), paraurethral cyst, anatomic variations of the hymen (figure 5)). Pelvic examination (speculum and/or bimanual) is reserved for those with genitourinary complaints or suspected genitourinary pathology, contraceptive counseling for an intrauterine device, or pregnancy. (See 'Preadolescent and adolescent females' above.)

●Anus and rectum – The perianal area should be examined for fissures, hemorrhoids, and other abnormal lesions (eg, condylomata acuminata (picture 13A-B), trauma, skin tags (picture 14)). Digital rectal examinations are not performed routinely as part of the regular physical examination of children. (See 'Anus and rectum' above.)