[Association between Y chromosome microdeletions and tes-ticular development in male pediatric patients with congenital reproductive system diseases].

OBJECTIVES: To analyze the distribution of Y chromosome azoospermia factor (AZF) microdeletions and their association with testicular development in male pediatric patients with congenital reproductive system diseases. METHODS: A prospective cohort study was conducted on pediatric patients admitted to the Department of Urology of Shanghai Children's Hospital from November 2021 to December 2023. The observation group included boys with hypospadias, cryptorchidism, or disorders of sex development (DSD), while the control group comprised boys with phimosis, indirect inguinal hernia, or hydrocele. Blood samples were collected for AZF microdeletion analysis using multiplex PCR to detect 15 sequence-tagged sites. Testicular ultrasound was performed to record testicular position and volume. Propensity score matching (PSM) was used to balance the groups. After matching, testicular volume differences were assessed. Stratified analyses compared testicular volume among children with AZF microdeletions, the control group, and children without AZF microdeletions in the observation group. RESULTS: A total of 493 children were enrolled (observation group: 463; control group: 30). The observation group consisted of 372 cases of hypospadias, 71 cases of cryptorchidism, and 20 cases of DSD. No Y chromosome microdeletions were detected in the control group. Four boys in the observation group had AZF microdeletions: one with cryptorchidism (AZFc+AZFd), one with isolated hypospadias (AZFc), and two with DSD (one with AZFb+AZFc+AZFd and one with AZFa). Ultraso-nography was performed for 888 testes. After PSM, testicular volume was significantly smaller in the observation group than that in the control group (P<0.01). Stratified analysis revealed a trend towards smaller testicular volumes in children with AZF microdeletions compared to the other two groups. CONCLUSIONS: The prevalence of Y chromosome microdeletions is higher in male children with congenital reproductive system diseases compared to the general population, particularly in those with DSD. Hypospadias, cryptorchidism, DSD, and AZF microdeletions may be associated with delayed testicular development in these children.