From the Research
Micropenis is diagnosed when a stretched penile length is 2.5 standard deviations below the mean for age and sexual stage, with a cutoff of below 2 cm at birth and below 4 cm after 5 years of age. This condition affects males and is often identified at birth during routine physical examination. The diagnosis requires careful measurement technique and comparison to age-appropriate nomograms, as stated in the study published in the Indian Journal of Pediatrics in 2023 1.
Diagnostic Criteria
The diagnostic criteria for micropenis include:
- Stretched penile length (SPL) 2.5 SD below the mean for age and sexual stage
- Cutoff of below 2 cm at birth and below 4 cm after 5 years of age
- Measurement taken by stretching the penis to its maximum length and measuring from the pubic bone to the tip of the glans
Etiologies
Micropenis can result from various etiologies, including:
- Hypothalamo-pituitary disorders (gonadotropin or growth hormone deficiencies)
- Genetic syndromes
- Partial gonadal dysgenesis
- Testicular regression
- Disorders of testosterone biosynthesis and action
- Associated hypospadias, incomplete scrotal fusion, and cryptorchidism are suggestive of disorders of sex development (DSD), as mentioned in the study 1.
Evaluation and Treatment
Evaluation should include:
- Basal and human chorionic gonadotropins (HCG)-stimulated gonadotropins
- Testosterone, DHT, and androstenedione levels
- Karyotype assessment Treatment aims at attaining penile length sufficient enough for urination and to perform sexual function, and may include hormonal therapy with intramuscular or topical testosterone, topical DHT or recombinant follicle stimulating hormone (FSH) and luteinizing hormone (LH), as stated in the study 1.
Important Considerations
It is essential to note that the role of surgery for micropenis is limited and has variable patient satisfaction and complication outcomes, and there is a need for long-term studies on the adult SPL achieved following treatment for micropenis in infancy and childhood, as highlighted in the study 1.