The penis is usually very small

Many people do not consider that small stones in the penis are very serious. First, it will affect the patient's sexual function. In addition, the penis is usually very small and the length of the erection is not long, which will lead to a decrease in sexual ability and cause a very disharmonious impact on the sex life between couples. It may even cause the patient to have fertility difficulties. The penis is usually very small and needs to be measured to see if it is within the standard range. If it is not within the standard range, special attention should be paid.

Pathological etiology

The causes of micropenis include: ① hypogonadism due to insufficient secretion of gonadotropin; ② hypogonadism due to excessive secretion of gonadotropin; ③ primary micropenis.

1. Hypogonadism due to insufficient secretion of gonadotropin

(1) Abnormal brain tissue structure: Children with anencephaly have no hypothalamic secretion function. Even if the pituitary gland develops normally, the lack of gonadotropin-releasing hormone leads to low testosterone secretion, resulting in micropenis. Congenital pituitary agenesis, hypothalamic dysfunction caused by partial corpus callosum dysplasia, occipital encephalocele with movement disorder and other midline brain development abnormalities all cause micropenis due to insufficient gonadotropin secretion. In addition, it also leads to multiple malformations of other systems.

(2) Congenital gonadotropin-releasing hormone deficiency without brain tissue abnormality: Micropenis caused by this type of reason is more common than the previous one. The specific cause is unclear. Most of them are various syndromes, such as Kallmann syndrome, Prader-Willi syndrome, Lawrence-Moon-Beidel syndrome, etc., often accompanied by multiple malformations. According to research, it is related to chromosome and gene abnormalities. There are also deficiencies of gonadotropin-releasing hormone and luteinizing hormone caused by endocrine and biochemical metabolic abnormalities.

2. Hypogonadism due to excessive secretion of gonadotropin

The secretion function of the hypothalamus and pituitary gland of this type of patients is normal, but the testicles undergo degeneration in the late pregnancy, resulting in a decrease in testosterone secretion, which leads to excessive secretion of gonadotropin through negative feedback. The main cause of micropenis lies in the testicles themselves, such as congenital testicular agenesis and incomplete testicular descent. Some patients have normal testicles, but their luteinizing hormone receptors are abnormal, so they cannot secrete enough testosterone. In addition, attention should be paid to whether there is any gender abnormality.

3. Primary small penis

In addition to the above reasons, a small number of patients have normal secretion of hormones in the hypothalamus-pituitary-testis axis, but have micropenis deformities, which grow more during puberty. The cause is unclear, but it is speculated that it may be due to delayed stimulation of gonadotropin in the late embryonic period and transient decrease in testosterone secretion. A small number of patients may also have androgen receptor abnormalities.

Patients with micropenis may have sex chromosome abnormalities, such as Klinefelter syndrome (47,XXY), poly-X syndrome (48,XXXY and 49,XXXXY), and polychromosomal abnormalities (69,XXY triploidy).

Disease Diagnosis

1. Hidden penis The penis is underdeveloped and hidden under the skin, like a small penis. However, the patient is obese and has thick subcutaneous fat, so the penis is buried in the subcutaneous fat tissue of the foreskin and pubic area.

2. Scrotal edema: The scrotum is excessively swollen and the penis is buried in it. However, there is a history of filariasis infection, and the scrotal skin is thickened, rough and cracked, sometimes involving the thigh and lower limb skin.