androgen insensitivity syndrome

Androgen
insensitivity syndrome. Transabdominal ultrasound (High frequency linear array probe) shows the presence of the left testis in the inguinal canal.
www.eurorad.org • CC by-nc-sa-4.0
Testicular
feminization - Complete androgen insensitivity syndrome. T2W axial view shows presence of vaginal opening (red arrow) between urethral orifice(green arrow) and anus(yellow arrow). Also note the presence of undescended testes (blue arrows) in both inguinal canals.
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Androgen
insensitivity syndrome. Transabdominal ultrasound (Low frequency convex array probe) demonstrate absence of uterus and ovaries.
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Androgen
insensitivity syndrome. T2 sagittal image shows absence of Mullerian structures (red arrow).
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Androgen
insensitivity syndrome. The axial T2-weighted image shows left testis and right testis in the inguinal canals bilaterally (red arrows).
www.eurorad.org • CC by-nc-sa-4.0
Androgen
insensitivity syndrome. Axial T2 image shows absence of Mullerian structures.
www.eurorad.org • CC by-nc-sa-4.0
Testicular
feminization - Complete androgen insensitivity syndrome. T1W image - axial view showing presence of undescended testis (blue arrows) in the inguinal canals.
www.eurorad.org • CC by-nc-sa-4.0
Testicular
feminization - Complete androgen insensitivity syndrome. Note the absence of both the ovaries (circles) on this T2W coronal view. Ileal loops are seen in the pelvis.
www.eurorad.org • CC by-nc-sa-4.0
Testicular
feminization - Complete androgen insensitivity syndrome. T2W coronal view shows presence of undescended testes (blue arrows) in both the inguinal canals.
www.eurorad.org • CC by-nc-sa-4.0
Androgen
insensitivity syndrome. Transabdominal ultrasound(High frequency linear array probe) shows the presence of the right testis in the inguinal canal.
www.eurorad.org • CC by-nc-sa-4.0
Testicular
feminization - Complete androgen insensitivity syndrome. T2W sagittal view showing presence of vagina (red arrow) in normal anatomical location between urinary bladder (green arrow) and rectum (yellow arrow). No uterus is visualised.
www.eurorad.org • CC by-nc-sa-4.0
Androgen
insensitivity syndrome • Androgen insensitivity syndrome - Ganzer Fall bei Radiopaedia
Saied A, Androgen insensitivity syndrome. Case study, Radiopaedia.org (Accessed on 04 Jan 2023) https://doi.org/10.53347/rID-41887 • CC by-nc-sa 3.0 (modified)
Androgen
insensitivity syndrome • Testicular feminization syndrome - Ganzer Fall bei Radiopaedia
Foladi N, Testicular feminization syndrome. Case study, Radiopaedia.org (Accessed on 04 Jan 2023) https://doi.org/10.53347/rID-88674 • CC by-nc-sa 3.0 (modified)
Androgen
insensitivity syndrome • Androgen insensitivity syndrome - Ganzer Fall bei Radiopaedia
Saman R, Androgen insensitivity syndrome. Case study, Radiopaedia.org (Accessed on 31 Dec 2023) https://doi.org/10.53347/rID-174116 • CC by-nc-sa 3.0 (modified)
Radiopaedia • CC-by-nc-sa 3.0 • de

Androgen insensitivity syndrome (AIS), also known as the testicular feminization syndrome, results from end-organ resistance to androgens, particularly testosterone. AIS may be complete or incomplete with variable imaging findings.

Epidemiology

The incidence may vary depending on whether it is complete or incomplete. Roughly estimated incidence rates are ~1 in 20,000 to 50,000 live births.

Clinical presentation

Patients can often present with primary amenorrhea.

Pathology

Affected individuals are genotypically male with a 46XY karyotype but with a female phenotype (male pseudohermaphroditism). Individuals often have bilateral cryptorchidism. The undescended testes often produce estradiol. There may be a blind-ending vagina.

Genetics

Thought to carry an X linked recessive inheritance  where multiple mutations in the androgen receptor (AR) gene has been localized to the long arm of the X chromosome (i.e. Xq11-13).

Subtypes

Although it is a disease spectrum it may be subtyped according to the extent of severity as:

  • complete androgen insensitivity syndrome (CAIS): Morris syndrome
  • incomplete: partial androgen insensitivity syndrome / Reifenstein syndrome

Radiographic features

General imaging features include:

Ultrasound

Usually, the first modality to locate the testes, and document absent uterus.

MRI

The modality of choice to accurately delineate Mullerian duct anomalies, and localize testes. It may also diagnose testicular malignancy, if any, in cryptorchid testes .

Treatment and prognosis 

These patients have an increased incidence of malignancy in the undescended testes:

Differential diagnosis

Mayer-Rokitansky-Kuster-Hauser syndrome has female karyotype with normal female genitalia, and ovaries, but the uterus is rudimentary or absent .

See also

Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu Androgenresistenz:
Kryptorchismus
 
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Seminom
 
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