A Clinical Approach to Diagnosis of Ambiguous Genitalia

Abstract

Disorders of sex development (DSD) are a sensitive and stressful condition for the family as well as the treating physician to deal with. The main issue in managing such cases is sex assignment. The decision is influenced by the cultural background, the sex of rearing, clinical features, the biochemical parameters including hormonal studies, the imaging reports, parental preference, fertility potential, and the assessment of mental make-up of the child when possible. In third world countries, there is diagnostic dilemma as most children with DSD present late and a detailed-lengthy work-up often delay their definitive treatment. In this article, the authors try to identify the important clinical features in children presenting with various types of DSD, which may aid in making a quick provisional clinical diagnosis and expediting the diagnostic work-up. The data have been gathered from 38 years of experience of the senior author while managing about 1200 cases of DSD in the pediatric intersex clinic at the tertiary care level institute.

INTRODUCTION

Even in today's world in the developing countries, a child born with ambiguous genitalia is associated with stigma and often kept hidden from the society for the fear of shame and the stress attached. But with the growing improved understanding, increasing awareness and advancement in medical and surgical combined approach, physicians have now become sensitive to the issues involved in the judicious management of such children.

Disorders of sex development (DSD) or differences in sex development or disorders of sex differentiation are defined as conditions involving the following elements; congenital development of ambiguous genitalia (e.g., 46, XX virilizing congenital adrenal hyperplasia (CAH); clitoromegaly; micropenis); congenital disjunction of internal and external sex anatomy (e.g., Complete Androgen Insensitivity Syndrome (CAIS); 5-alpha reductase deficiency (5ARD); incomplete development of sex anatomy (e.g., vaginal agenesis; gonadal agenesis); sex chromosome anomalies (e.g., Turner syndrome; Klinefelter syndrome; sex chromosome mosaicism); and disorders of gonadal development (e.g., ovotestes).[1]

CLASSIFICATION AND NOMENCLATURE

The classification based on gonadal histology was widely used previously. Since then, many classifications and nomenclature for DSDs have flooded the literature.[1,2,3,4,5] The one that is commonly followed classifies DSD into 46, XX DSD, 46, XY DSD, and the sex chromosome DSD.[4,5] A complete evaluation of DSD case entails clinical presentation including the status of gonads, chromosomal analysis, hormonal evaluation, radiology (genitogram, ultrasound [USG], magnetic resonance imaging [MRI]) to look for Mullerian structures, endoscopy, and laparoscopy/laparotomy. More often than not, most physicians rush through the clinical examination and focus toward the karyotyping, hormonal profile, and the imaging modalities, including MRI. The starting point of all these algorithms has been defined by the karyotype or the gonadal histology.

However, the important markers in clinical examination are often overlooked due to lack of knowledge and experience of most physicians dealing with pediatric DSD cases. The prevalence of DSD is difficult to assess but may be not uncommon (1:2500–5000 live births),[6] however as lesser number of DSD cases actually seek medical advice, it may point to the ignorance and the stigma associated with this condition.

This article aims to unfold the clinical clues to diagnose different types of DSDs gathered over 38 years of experience of the senior author in managing more than 1200 patients of DSD at a tertiary level institute. This will not only reduce the number of unnecessary investigations and the repeated genital examinations but also save the child and the family of the psychological trauma associated with it.

CLINICAL HISTORY AND EXAMINATION

A complete family history, including the family tree and history of consanguinity, is important in cases of DSD. Consanguinity (about 10% incidence from our center) has a reported role to play in disorders of androgen synthesis, action, and functions, for example, CAH, pure gonadal dysgenesis (PGD), and 5ARD.[6] History of drugs/medications, especially steroidogenic preparations, including oral contraceptive pills taken by the mother during pregnancy should be noted.[7,8,9] Sibling death or any unexplained neonatal deaths in the family points toward CAH. History of fertility issues in parents, grandparents, aunts and uncles, and history of adoption should be noted carefully.

In older children, the timing of genital and pubertal development is important in cases of 5ARD. CAIS or PGD cases may present with a history of amenorrhoea. Sexual preferences, way of dressing, and tomboy nature should be noted. Learning difficulties and female like voice in cases of Klinefelter's syndrome.

A complete physical examination includes a general physical examination (GPE), specific examination, and a systemic examination. Points to note on a GPE are the general condition of the child (could be sick in cases of CAH), hypertension (cases of impaired androgen biosynthesis), height (stunted in Turner's and tall in Klinefelter's syndrome), weight (increased in CAH), syndromic facies, dysmorphic features, webbed neck, high-arched palate (Klinefelter's syndrome) and skeletal deformities. Any abnormal virilized or cushingoid appearance of the mother should be checked.[10]

Specific examination includes a detailed genital examination (phallus size and shape, prepuce, clitoris, urethral meatus, vaginal orifice, urogenital sinus, labioscrotal folds, gonads whether symmetric, or asymmetric/location/size/consistency), pigmentation pattern, hair growth pattern, and breast development. When possible a per-rectal examination should be added to look for the presence of the uterus. In other cases, the presence of uterus can be ensured by pelvic USG/MRI or a genitogram and finally a laparoscopy. The genital examination should be conducted after proper consent or assent in a warm room with full privacy and the child in supine frog-legged position.

The asymmetry of inguinoscrotal region refers to the presence of a gonad in this region. A palpable gonad is usually a testis or an ovotestis because ovaries and the streak gonads do not descend.[10] Thus, asymmetry points toward mixed gonadal dysgenesis (MGD) or TH (Ovotesticular DSD).[7] Symmetry refers to symmetrical descent or nondescent of bilateral gonads which could again be testes/ovotestes or dysgenetic testes in cases of 46, XY DSD and points toward AIS or 5ARD.

Criteria for suspecting DSD include: (1) Overt genital ambiguity (e.g. cloacal exstrophy); (2) Apparent female genitalia with an enlarged clitoris and posterior labial fusion (e.g., CAH); (3) Apparent male genitalia with bilateral undescended testes, hypospadias, or micropenis; and (4) Discordance between genital appearance and a prenatal karyotype.[1] In older children, the criteria for evaluation also include: (1) Previously unrecognized genital ambiguity; (2) Inguinal hernia in a girl (e.g., CAIS); (3) Delayed or incomplete puberty; (4) Primary amenorrhea or virilization in a girl; (5) Breast development in a boy; and (6) Gross or cyclic hematuria in a boy[1,10,11] and a suprapubic mass (hematocolpos) with breast enlargement after the age of puberty in a boy with the history of hypospadias and undescended gonads.

Typical features in a classical case of DSD have been summarized in Table 1 and have been detailed below.

Table 1.

Clinical presentation of common prototype cases of disorders of sexual development

	Phenotypic sex	Genotypic sex	Prepuce	Phallus	Labioscrotal folds	Gonads#	Urethral meatus	Pigmentation	Pubic hair	Uterus (p/r)	Breast development (Tanner’s stage)	Fertility	Figure
TH	Male	46,XX (94%); 46,XY (6%)	Supple, good sized	Triangular phallus with narrow base	Asymmetry	T + O/T + OT/O + OT/OT + OT, OT commonest with only one draining duct	Severe chordee and hypospadias, wide meatus, everted mucosal lining	Normal	Normal	Present; 60% - Good sized, 30% - Hypoplastic; 10% - Absent if XY	I-III	Female can be fertile	3
MPH
CAIS	Female	46,XY	Absent	Clitoris	Labia like, empty	T + T, descended	Female like, vaginal Pit+	Absent	Absent	Absent	IV/V	Infertile females	2a
PAIS	Males	46,XY	Normal	Small size	Symmetric	T + T	Hypospadias, blind vaginal pouch	Normal	Decreased	Absent	Gynaecomastia	Can be fertile
5ARD	Females Initially, males at puberty	46,XY	Not deficient	Small size	Symmetric, empty till puberty	T + T	Perineal hypospadias	Normal	Sparse	Absent	I/II	Rare due to low volume ejections	2b
PMDS	Male	46,XY	Normal	Normal-small size phallus	Asymmetric	T+T (Undescended + TTE)	Normal urethral meatus	Normal	Normal	Atretic	I	Rarely fertile males
FPH
CAH	Virilized Female	46,XX	Absent	Enlarged phallus/clitoris (Prader scale I-V)	Symmetric, variable degree of labial fusion	O+O	Separate urethral and vaginal orifice to common urogenital sinus	Hyperpigmentation (perineum, axilla, areola)	Excessive	Present	II-III	Fertile female (50%)	1a
MGD	Female	45, XO/46,XY	Deficient	Cylindrical small phallus	Asymmetric/empty	STK + T/STK + DYS T (may descend)	Severe hypospadias, vaginal and urethral orifices seen separately	Normal	Sparse	Present - dysplastic and cylindrical	I/II	Infertile	1b
DMP	Female	46,XY; 46, XO/XY	Deficient or snugly fitting prepuce	Cylindrical small phallus	Symmetric, empty	DYS T + DYS T , Undescended, both ovarian location	Severe hypospadias, vaginal and urethral orifices seen separately	Normal	Sparse	Present - dysplastic and cylindrical	I/II	Infertile
PGD	Female	45,XO; 45, XO/46,XY (5%)	Absent	Normal clitoris	Separate labia	STK + STK (ovarian location)	Separate urethral and vaginal openings	Normal	Normal	Present	I-II; shield chest	Infertile

^#T: Testis, O: Ovary, OT: Ovotestis, STK: Streak, DYS: Dysgenetic, TTE: Transverse testicular ectopia. TH: True hermaphrodite, MPH: Male pseudo hermaphrodite, CAIS: Complete androgen insensitivity syndrome, PAIS: Partial androgen insensitivity syndrome, 5ARD: 5 alpha reductase deficiency, PMDS: Persistent Mullerian duct syndrome, MGD: Mixed gonadal dysgenesis, FPH: Female pseudo hermaphrodite, CAH: Congenital adrenal hyperplasia, MGD: Mixed gonadal dysgenesis, DMP: Dysgenetic male pseudo hermaphrodite, PGD: Pure gonadal dysgenesis

46, XX DISORDERS OF SEX DEVELOPMENT/FEMALE PSEUDOHERMAPHRODITE

The most common cause of FPH is CAH secondary to androgen excess due to fetal causes (21-hydroxylase deficiency (95%), 11-hydroxylase deficiency (5%) or 3 β- hydroxysteroid dehydrogenase deficiency); others being fetoplacental (aromatase deficiency, oxydoreductase deficiency) and maternal causes (intake of virilizing drugs and virilizing tumor).

Congenital adrenal hyperplasia

The virilizing form of CAH, the key feature, is clitoromegaly; its degree may range from mild to severe according to the Prader scale. Clitoromegaly can be clinically defined as when the clitoris becomes visible in the lying down position with legs normally opposed. The labioscrotal folds are symmetrical with no palpable gonads and may have varying degree of midline fusion depending on the severity. There is associated hyperpigmentation of the perineum, the axilla, areola, and the body folds. Excessive hair growth is the third dominant clinical feature in patients of CAH [Figure 1a]. The uterus is present on imaging or palpable on per rectal examination.

Figure 1.

(a) Congenital adrenal hyperplasia: 12-year-old girl presented with virilization, clitoromegaly, hyper-pigmentation and excessive pubic hair; (b) Mixed gonadal dysgenesis: Cylindrical and small phallus, perineal hypospadias, deficient prepuce, penoscrotal transposition and undescended gonads (original)

Depending on the degree of virilization, these children are either reared as girls or as boys. When reared as girls, they have a tomboy attitude. There may be maternal history of steroids intake or virilization. History of sibling death indicates toward the severe salt-wasting variety of CAH. Male neonates may present with dehydration and hyponatremic, hypokalemic shock in the classical variety of CAH.

The diagnosis is confirmed after karyotyping (46, XX) and hormonal assay. If the 17-hydroxyprogesterone level is elevated, a diagnosis of CAH can be made. Determining the levels of 11-deoxycortisol and deoxycorticosterone will help to make a differential diagnosis between 21-hydroxylase and 11 β-hydroxylase deficiencies. If the levels are elevated, a diagnosis of 11 β-hydroxylase deficiency could be made whereas low levels confirm 21-hydroxylase deficiency.[10] It is supplemented by the presence of the uterus seen on a pelvic USG or a genitogram or on genitoscopy. Feminizing genitoplasty and medical therapy (glucocorticoid/mineralocorticoids supplementation) are the basic management tools.[12,13] Occasionally, in late presenters, male genitoplasty has also been performed.[13,14]

46, XY DISORDERS OF SEX DEVELOPMENT/MALE PSEUDO HERMAPHRODITE

This includes patients with 5ARD, AIS and androgen-receptor deficiency syndrome. In all these types of MPH, both the gonads are symmetrical, i.e., either both are descended, or both are undescended. Hypospadias with cryptorchidism increases the likelihood of MPH type DSD.

5-alpha-reductase deficiency

In cases of 5ARD, the child typically presents at 3–5 years of age with a severe degree of hypospadias, a small-sized phallus, bifid scrotum, and bilateral undescended testes [Figure 2b]. The final diagnosis is made by hormonal evaluation. At puberty, these clinical features prevail, but both the gonads may descend, scrotum becomes hyperpigmented, and scrotal rugae develop and the phallic length improves, though it remains smaller than peers. They also have increased muscle mass and deepening of the voice. They have decreased facial and body hair.

Figure 2.

(a) Complete androgen insensitivity syndrome: 4-months baby, reared as girl, small clitoris, well-developed labial folds, but both gonads descended and 46,XY karyotype; (b) 5-alpha-reductase deficiency: Small phallus, bifid scrotum, cryptorchidism, and perineal hypospadias (original)

5ARD is diagnosed when the fluorescent in situ hybridization (FISH) technique reveals 46, XY and presence of SRY gene on Y chromosome; and the testosterone: Dihydrotestosterone levels are elevated.

Androgen insensitivity syndrome

An infant born with AIS is phenotypically female with both gonads palpable in the labial folds and the vaginal opening/pit may be visible in the vestibule [Figure 2a]. Young girls typically presenting with amenorrhea or with unilateral or bilateral inguinal hernia raise high suspicion for AIS. Depending on the severity of androgen resistance, the clinical features may vary. In the case of CAIS, the child is reared as female, has a normal looking clitoris, vaginal pit/introitus, labia minora, and majora. Bilateral gonads are symmetric and can be intra-abdominal or extra-abdominal and partially descended and rarely completely descended in the labial folds. The vaginal orifice varies from a normal looking introitus to a vaginal pit but is always blind ending. There is associated absence of pubic, axillary, and facial hair. At puberty, there is the substantial development of breast tissue and other female secondary sexual characteristics, and hence CAIS is also known as testicular feminizing syndrome. The incidence of CAIS in girls with inguinal hernias is approximately 1%.[14] AIS can present in siblings with phenotypic diversities.[15,16]

In partial androgen insensitivity syndrome (PAIS), there is small phallus with severe degree of hypospadias and variable degree of undescended testes. However, the level of both the testes whether descended or undescended, is symmetric. The scrotum maybe bifid or doughnut-shaped and is poorly developed. At puberty, they usually do not develop gynecomastia, and there is no significant growth in the phallus size. The axillary and pubic hair is sparse.

PAIS-like phenotype may also be observed in: (1) Defects in androgen production, for example, partial gonadal dysgenesis, SRY, SF-1, WT-, MAMLD1 mutations; luteinizing hormone (LH) receptor mutation; biosynthetic enzyme deficiencies-17,20-lyase deficiency, P450 oxidoreductase deficiency, 17 β-hydroxysteroid dehydrogenase deficiency type 3, 5ARD type 2, and 2) Genetic Syndromes, for example, Klinefelter, Smith–Lemli–Opitz, Denys-Drash, Frasier.[17]

The diagnosis of AIS is confirmed by karyotyping suggestive of 46, XY (X linked recessive/autosomal recessive) DSD and increased LH, testosterone, oestradiol and sometimes increased follicle-stimulating hormone (FSH).

Persistent Mullerian duct syndrome

They present as normally virilized males and most cases are detected incidentally during the time of surgery for undescended testes or inguinal hernia. Gonads are asymmetric. The undescended gonad may present as an irreducible content of an inguinal hernia. The contralateral scrotum is usually empty. In a few cases, both the testes are found on the same side, but one may have transverse lie, i.e., transverse testicular ectopia. They commonly present with bilateral nonpalpable undescended testes with no hypospadias. There is uterus felt on per rectal examination.

SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT

True hermaphrodite

Patients may present either at birth with ambiguous genitalia or may often present later in life. Those who are reared as males, typically have a triangular penile shaft. The width at the base of the penile shaft is usually narrow, which gradually broadens up till the tip of the shaft resulting in a triangular shape of the penis. Penoscrotal transposition of moderate-to-severe degree is usually present. The presence of a bipolar palpable gonad of dual consistency (ovary is firmer, and the testis component is softer) is confirmatory.[18] Ovary and testis when present are arranged longitudinally (80%), however, ovary can be placed in a hilar location in 20% cases. There is only one draining duct even with the ovotestis. Never ever both the vas and the fallopian tube will be present with ovotestis. The absence of one or rarely both the gonads from the scrotum is associated with severe penoscrotal hypospadias. The hypospadiac meatus in cases of TH is usually wide with everted mucosa. The mucosal lining may line the entire urethral plate and may extend up till the navicular fossa [Figure 3a].

Figure 3.

(a) True hermaphrodite: triangular phallus, right descended gonad with dual consistency, severe hypospadias, and wide urethral meatus with mucosa lining the urethral plate. (b) A 16-year-old patient postrepair of hypospadias and undescended testes, presented with pain and lump per abdomen, cyclic hematuria, and postpubertal breast development; Retrograde genitogram showed the presence of uterus (original)

In case the child comes after pubertal age, there is often a history of monthly cyclic hematuria from a good sized phallus, masquerading the normal menstrual cycle. There is also breast enlargement and development of female looking facial features. On a per-rectal examination, a full-sized enlarged uterus or even a mass may be palpable anteriorly in cases of associated hydrometrocolpos [Figure 3b]. The uterus is present in 90% cases, well developed in 60% cases, hypoplastic and cord like in 30%, and absent in about 10% cases. It is bulky only in 10%–15% cases.[18] In such cases, there may be cyclic hematuria and bilateral breast development due to the effect of estrogen.[18] If the child is reared as female, hydrometrocolpos may be the primary presentation. THs have sometimes been reported to be fertile females. The presence of both ovary and testis on histology confirms the diagnosis. The diagnosis of ovotestes is confirmed by laparoscopy or laparotomy and longitudinal gonadal biopsy is taken.[19] Karyotype of 46, XX in 90% cases supplements the diagnosis of TH.

Mixed gonadal dysgenesis and dysgenetic male pseudohermaphrodite

Characterized by varying degrees of dysgenetic gonads, MGD, and dysgenetic male pseudohermaphrodite (DMP) are considered under the same spectrum of DSD. In MGD, the child presents with hypospadias with severe chordee. The prepuce is deficient and snugly fits the penile shaft. The phallus is cylindrical but small. There is labioscrotal asymmetry [Figure 1b]. At least, one of the gonads or both is absent from the scrotum due to the presence of dysgenesis of the gonad/s. Or in other words, mostly one gonad is palpable, and it may have not descended completely. There is associated severe penoscrotal transposition. There is severe variety of hypospadias with normal looking or fish-mouthed urethral meatus, and the mucosal lining is not everted.[12] The urethral and vaginal openings can be seen separately in the perineum due to incomplete virilization. The uterus is present, is atretic and may be palpable as a cord.[12,20]

Children with DMP present exactly as in MGD except that both the gonads are undescended. Typically, a DMP case has a female like external genitalia, phallus akin to clitoris with severe hypospadias and separate urethral and vaginal openings seen. The labioscrotal folds are symmetrical and the labial folds/scrotum are poorly developed. There are bilateral dysgenetic gonads placed intra-abdominally in ovarian location. In severe degree of dysgenesis, streak gonads are found bilaterally, and the condition is called PGD. DMP, PGD, and MGD are best diagnosed by laparoscopy and a gonadal biopsy in addition to karyotyping. A 45, XO/46, XY mosaicism in a case of DSD points toward MGD, DMP, or rarely TH. A streak gonad or a dysgenetic gonad is a must for making the diagnosis of Dysgenetic DSD. A streak gonad is defined as a gonad showing abnormal architecture and ovarian-type wavy stroma (but without the presence of the graffian follicles), with the absence of germ cells or other specific features. A dysgenetic/dysplastic gonad on histology shows testicular features with abnormal architecture and ovarian-type gonadal stroma.[21] The degree of descent of a dysgenetic gonad depends on the amount of degree of dysgenesis present in the gonad. In MGD, at least, one of the gonads is palpable; however, it is usually dysgenetic despite it has descended down to the bottom of the scrotum.[21]

CLINICAL APPROACH AND CONFIRMATION OF DIAGNOSIS

After a thorough examination as detailed above, a differential diagnosis can be reached as suggested in the flowchart [Figure 4]. Confirmation of each of them would require a detailed work-up including chromosomal evaluation, radiological investigations, hormonal evaluation, genitoscopy, laparoscopy/laparotomy, and gonadal biopsy for diagnostic and therapeutic purposes.[1,18,22,23] If karyotyping reveals 46, XY it points toward MPH or 46, XY DSD and 46, XX toward FPH, most common variety being CAH. In TH 46, XX is the most common karyotype; 10% may be 46, XY or may even have mosacism. A 46, XY with mosacism, 45 XO/XY is usually present in MGD. Imaging entails X-rays for bone age in CAH; USG/MRI to look for internal gonads; retrograde genitogram to look for the presence of vagina and uterus. A deviation of the uterine image from the midline would suggest an ovarian gonad to that side and an undescended testis on the opposite side in a case of TH. Hormonal evaluation will include 17 hydroxyprogesterone, testosterone, dihydrotestosterone, LH, FSH, estradiol for CAH, 5ARD, and AIS. Ultimately laparoscopy/laparotomy hold diagnostic and therapeutic potential and aid in gonadal biopsy in select cases of DSD. The disadvantage of laparoscopy is that one cannot get the feel of the dysgenetic gonad or the ovotestis to differentiate the gonadal consistency (soft in cases of testis and a firm feel in a case of ovary). DSD cases must also be differentiated from the non-DSD cases such as labial adhesions (with a thin midline film), micropenis, aphalia, lymphangioma of the clitoris, cloacal exstrophy, and several other genital abnormalities.

Figure 4.

Guide to reach the provisional clinical diagnosis in a case of disorders of sex development (original)

CONCLUSION

• To make a diagnosis of a case of DSD, as was followed traditionally, the history and clinical examination should be the strongest foundation pillars which should be supplemented by the latest karyotyping, imaging, hormonal assays, gonadal biopsy, and endoscopy/laparoscopy

• The simple clinical clues and the diagnostic workup suggested here would help most primary physicians at peripheral centers to pick up the DSD cases with provisional diagnosis and refer these to the tertiary centers for proper counseling and management

• The recording of typical features on the first genital examination could save the child as well as the family from the stress of unnecessary repeated genital examinations.

Ethical Statement: Ethical standards of care and consent were followed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.