Postnatal testicular regression mircopenis and microcephaly: conformation of a new syndrome?

Testicular regression may develop at various phases of the intrauterine period and the clinical findings vary depending on the timing of the intrauterine phase. On the other hand, postnatal regression of the testicles is rare and few cases have been reported in the literature. Our patient presented with undescended testicles, micropenis, flat scrotum and microcephaly. The patient's levels of basal luteinizing hormone (LH) were low/normal and follicle stimulating hormone (FSH) was high. No response was obtained in the human chorionic gonadotropin (HCG) stimulation test. The levels of inhibin B and anti Mullerian hormone (AMH) were found to be low. Penile growth response to intramuscular testosterone injections was 2.5 cm. Testicles were visualized bilaterally in inguinal canal by ultrasound examination initially but by 2 years of age no testicular tissue was observed during inguinal exploration. In conclusion we recognized postnatal testicular regression in our patient that had started in the intrauterine period and persisted into infancy. The genital system anomalies, microcephaly and motor retardation in our patient confirm the hypothesis of Parisi et al. of a novel condition of postnatal regression and micropenis.