15. Testicular Feminization Syndrome (Complete Androgen Insensitivity) | USMLE Step 1 скачать в хорошем качестве

15. Testicular Feminization Syndrome (Complete Androgen Insensitivity) | USMLE Step 1

𝐒𝐮𝐛𝐬𝐜𝐫𝐢𝐛𝐞 𝗙𝐨𝐫 𝗠𝐨𝐫𝐞 𝗜𝐧𝐟𝐨𝐫𝐦𝐚𝐭𝐢𝐨𝐧 𝐨𝐧 𝗛𝐞𝐚𝐥𝐭𝐡 👩‍⚕‍ 𝐚𝐧𝐝 𝗠𝐞𝐝𝐢𝐜𝐢𝐧𝐞💉🩺💊 𝐘𝐨𝐮𝐭𝐮𝐛𝐞 :    / @draishwaryakelkar   📌𝗙𝗮𝗰𝗲𝗯𝗼𝗼𝗸 :   / draishwaryakelkar   📌𝗧𝘄𝗶𝘁𝘁𝗲𝗿:   / aishwayadr   📌𝗜𝗻𝘀𝘁𝗮𝗴𝗿𝗮𝗺 :   / clinical.learning   ✨ Testicular Feminization Syndrome (Complete Androgen Insensitivity) | USMLE Step 1/2 CK | Primary Amenorrhea, Dx & Management Testicular Feminization Syndrome—now called Complete Androgen Insensitivity Syndrome (CAIS)—is a high-yield cause of primary amenorrhea and a classic USMLE vignette. Patients are 46,XY with loss-of-function mutations in the androgen receptor (AR) (X-linked), so tissues cannot respond to testosterone or DHT. Sertoli cells still make AMH, causing Müllerian regression (no uterus, cervix, or upper vagina), while Leydig cells produce testosterone that aromatizes to estradiol, yielding normal breast development at puberty. Because the body can’t sense androgens, pubic/axillary hair is sparse or absent, the external genitalia appear female, and the vagina ends in a short/blind pouch. Testes are present but undescended (inguinal canal, labia, abdomen), and childhood “inguinal hernia in a girl” is a red flag. Labs often show elevated or high-normal testosterone and LH, normal/low FSH, and absent menses. Imaging demonstrates absent uterus on pelvic ultrasound/MRI; karyotype is 46,XY and AR genetic testing can confirm. Differentiate from Müllerian agenesis (MRKH)—which has normal pubic hair and functioning ovaries—and 5-α-reductase deficiency, where undervirilized external genitalia at birth virilize at puberty as testosterone rises. Management centers on safety, development, and counseling. Because estrogenization at puberty relies on endogenous aromatization, most guidelines support deferring gonadectomy until after puberty to permit full breast and bone maturation, then post-pubertal bilateral gonadectomy to mitigate the increasing testicular malignancy risk with age. After removal, provide estrogen replacement therapy (no progestin needed without a uterus), plus bone health optimization (calcium, vitamin D, weight-bearing exercise; DXA based on risk). Create a comfortable sexual function plan with progressive vaginal dilation as first-line if needed; surgical options are reserved for refractory cases. Offer genetic counseling, sensitive psychosocial support, and discuss fertility (patients are infertile; family-building via adoption or gamete/gestational options depending on individual goals). Exam pearls: 46,XY with female phenotype, no uterus, scant body hair, normal breasts, undescended testes = CAIS; MRKH has 46,XX with normal hair and ovaries; 5-α-reductase deficiency shows pubertal virilization. Know the triad AMH → no Müllerian, androgen receptor defect → no virilization, aromatization → breast development—that’s the USMLE logic. #AndrogenInsensitivity #CAIS #TesticularFeminization #PrimaryAmenorrhea #USMLEStep1 #USMLEStep2CK #DSD #AmenorrheaWorkup #UndescendedTestes #InguinalHernia #MullerianAgenesis #5AlphaReductaseDeficiency #EstrogenTherapy #BoneHealth #GeneticCounseling #MedicalEducationUSA #USMLEPreparation #Step2CKPrep #WomensHealth