Association of Levels of Serum Inhibin B and Follicle-stimulating Hormone with Testicular Vascularity, Volume, and Echotexture in Children with Undescended Testes

AIMS: The aim of our study was to assess the association between reproductive hormones (inhibin B [inh B], follicle-stimulating hormone [FSH]) with testicular volume, echogenicity, and blood flow (resistive index [RI]) in children with undescended testis (UDT). SETTINGS AND DESIGN: This was a prospective study of 1-year study duration. MATERIALS AND METHODS: A total of 33 patients (16 unilateral and 17 bilateral) UDTs aged 5–12 years with palpable UDT were included in the study. Morning fasting blood samples were taken for estimation of serum inh B and FSH as well as inh B/FSH ratio. Testicular ultrasound was done to compute testicular volume, testicular echogenicity, and testicular vascularity in terms of RI. RESULTS: The mean age of patients enrolled in the study was 8.29 years for unilateral UDT and 7.97 years in bilateral UDT and it was comparable. The study groups were further subdivided into two age-wise subgroups school goers (5–8 years) and prepubertal (9–12 years). The values of inh B, FSH, and inh B/FSH ratios as well as mean testicular volume were comparable between both groups and subgroups. Overall mean testicular volume had a positive correlation with FSH, inh B, and inh B/FSH, but statistical significance was reached only for inh B (P < 0.001) in children with both unilateral and bilateral UDT. Apart from five patients with hypoechogenicity within the testis, all remaining testes were of homogenous echotexture with no instances of irregular echogenicity or tumor. Children with RI >0.6 were separately studied. The incidence of high RI (>0.6) was also comparable in unilateral or bilateral disease. These subjects had unfavorable biochemical parameters in terms of low inh B levels and high FSH levels. CONCLUSIONS: Our findings hint to the fact that palpable UDT forms a homogenous group, whether unilateral or bilateral, whereas impalpable testes may form a separate category and need further studies to substantiate this hypothesis.