bubble_chart Overview

Subcutaneous nodules of the male reproductive system are a common condition, often coexisting with subcutaneous nodules of the urinary system. According to literature statistics, the concurrent occurrence of subcutaneous nodules in both systems ranges from 50% to 80%, while isolated subcutaneous nodules of the male reproductive system account for only 10%.

bubble_chart Pathogenesis

There are two routes of infection for male genital tract subcutaneous nodes: ① Hematogenous infection: The onset of male genital tract subcutaneous nodes is similar to renal subcutaneous nodes, both being secondary sexually transmitted disease changes from subcutaneous node lesions in other organs of the body. The subcutaneous node bacilli invade the male genital system through the bloodstream. ② Urinary tract infection: On the basis of renal subcutaneous nodes, the subcutaneous node bacilli invade the male genital system through urine, thus also representing a secondary sexually transmitted disease change of renal subcutaneous nodes. Moreover, the more severe the renal subcutaneous node lesions, the higher the likelihood of concurrent male genital tract subcutaneous nodes. In a group of 143 cases of renal subcutaneous nodes, the complication rate of male genital tract subcutaneous nodes was 13% in miliary renal subcutaneous nodes, 58% in caseous renal subcutaneous nodes, and 100% in cavitary renal subcutaneous nodes. Currently, it is believed that male genital tract subcutaneous nodes, whether through hematogenous or urinary tract infection, often begin in the prostate and seminal vesicles before spreading to the vas deferens. From there, the infection extends through the lumen or lymphatic vessels of the vas deferens to the epididymis, where lesions first appear in the tail of the epididymis before spreading to other parts of the epididymis and the testis. Hematogenous infection of the male genital tract subcutaneous nodes can directly cause epididymal subcutaneous nodes, with such infections typically starting in the head of the epididymis. Clinically, urinary tract infections are more common, while hematogenous infections are relatively rare.

bubble_chart Pathological Changes

The condition primarily involves the formation of subcutaneous nodules and caseous necrosis in the reproductive organs such as the prostate, seminal vesicles, vas deferens, and epididymis. After the expulsion of caseous material, cavities may form, or the tissue may undergo fibrosis, leading to the formation of masses. Subcutaneous nodules in the prostate may occasionally rupture into surrounding tissues, forming sinuses in the perineal region. Subcutaneous nodules in the vas deferens can cause it to thicken and harden, resulting in a beaded appearance. Epididymal lesions typically spread from the tail to the body and head of the epididymis and may extend beyond it, forming cold abscesses that adhere to the scrotum. These abscesses may rupture and discharge pus, leading to chronic sinuses. Subcutaneous nodules in the epididymis can also spread to the testes, causing testicular subcutaneous nodules.

bubble_chart Clinical Manifestations

Subcutaneous nodules of the male reproductive system mostly occur in young and middle-aged adults. Domestic statistical data show that 78% of patients are between the ages of 20 and 40. Subcutaneous nodules of the male reproductive system generally present as a slow sexually transmitted disease process, often being a bilateral condition, though symptoms may appear sequentially during the course of the disease. Subcutaneous nodules of the prostate and seminal vesicles usually have no obvious symptoms and are often discovered during rectal examinations performed due to symptoms caused by epididymal subcutaneous nodules, revealing infiltration and hard nodules in the prostate and seminal vesicles. Destruction of the prostate parenchyma can reduce semen quantity, thereby lowering or even eliminating fertility. Some individual cases may present with hemospermia.

The clinical manifestations of subcutaneous nodules in the male reproductive system often resemble those of epididymal subcutaneous nodules. The disease progresses slowly with mild symptoms, and the epididymis gradually enlarges, occasionally accompanied by a dragging sensation or mild dull pain, which may not attract the patient's attention. As a result, the condition is often discovered incidentally. The lesions spread from the tail of the epididymis to the body and head, eventually affecting the entire epididymis. As the disease progresses, the epididymis may adhere to the scrotum, leading to caseous necrosis and the formation of a cold abscess, which may eventually rupture into a sinus and persist unhealed. A few cases of epididymal subcutaneous nodules may present with acute symptoms due to secondary infection, where the patient experiences sudden fever, redness, swelling, and pain in the scrotal epididymal region, forming an abscess that ruptures. After the acute symptoms gradually subside, the condition transitions into a chronic phase. Subcutaneous nodules of the vas deferens manifest only as thickening and hardening due to fibrosis, appearing cord-like or beaded. Bilateral involvement of the vas deferens and epididymal subcutaneous nodules can lead to infertility.

bubble_chart Diagnosis

The diagnosis of male genital subcutaneous node is generally not difficult and is primarily based on the aforementioned clinical manifestations, as well as physical examination of the scrotal area and digital rectal examination. Irregular enlargement of the prostate and seminal vesicles, the presence of subcutaneous node nodules, nodules in the epididymis, and beaded thickening of the vas deferens are all signs that can confirm the diagnosis. In cases where epididymal lesions adhere to the scrotum and ulcerate, forming a chronic sinus, the diagnosis of subcutaneous node lesions becomes even more definitive. For the few cases where the diagnosis remains unclear, semen culture or smear examination for subcutaneous node bacilli, as well as examination of prostate fluid for subcutaneous node bacilli, may be performed. Although the chances of positive results are low, these tests still hold reference value. X-ray examination may sometimes reveal calcification in the prostate. Seminal vesiculography can demonstrate lesions in the vas deferens and seminal vesicles, such as stenosis, obstruction, irregular filling, dilation, or destruction. However, in many cases, the contrast agent fails to pass due to obstructive lesions, resulting in unsuccessful imaging, thereby limiting its practical application value.

In diagnosing male genital subcutaneous node, it is also necessary to differentiate it from prostate cancer, gonococcal or nonspecific epididymitis, and scrotal filariasis. Generally, this is not difficult and can be clarified through medical history, laboratory tests, and puncture biopsy.

When diagnosing male genital subcutaneous node, the relationship with the urinary system must be emphasized. Renal subcutaneous node may coexist without presenting urinary symptoms, making male genital subcutaneous node the only clue. Therefore, routine urine tests for subcutaneous node bacilli are essential, and systematic urinary system examinations should be conducted when necessary to achieve a definitive diagnosis.

bubble_chart Treatment Measures

The treatment of male genital tuberculosis must include systemic treatment and treatment of the male genital system. Systemic treatment is the same as that for general tuberculosis. The treatment of the male genital system includes both drug therapy and surgical treatment:

(1) Drug Therapy Male genital tuberculosis responds well to anti-tuberculosis drugs. Both prostate and seminal vesicle tuberculosis can be treated conservatively with medication. The drug treatment method is the same as that for renal tuberculosis, involving the combined use of two or three drugs, primarily isoniazid, streptomycin, and rifampin. The usual course of treatment is 6 to 12 months based on experience.

(2) Surgical Treatment The surgical treatment of male genital tuberculosis primarily addresses epididymal tuberculosis. Resolving epididymal tuberculosis aids in the healing of tuberculosis in other parts of the genital system (seminal vesicles, prostate). Surgery is performed after the epididymal lesions have localized, similar to renal tuberculosis, and anti-tuberculosis drugs are required before and after the surgery.

Indications for epididymectomy:

1. Unilateral epididymal tuberculosis.

2. Formation of a cold abscess in one epididymis.

3. Formation of cold abscesses in both epididymides.

4. Chronic sinus formation in the scrotum due to unilateral epididymal tuberculosis.

5. Chronic sinus formation in the scrotum due to bilateral epididymal tuberculosis.

During epididymectomy, the cut end of the vas deferens should be severed as high as possible and transplanted subcutaneously to prevent retraction and avoid the formation of tuberculous abscesses in the scrotum from residual tuberculosis lesions in the vas deferens. When removing the epididymis, the testis should be preserved as much as possible. If the testis is already affected by the disease, the affected portion of the testis should be excised to preserve some testicular function. If the disease has affected most of the testis and preservation is impossible, the testis may be removed entirely.

Opinions on the management of the contralateral vas deferens during epididymectomy are inconsistent. For patients with aspermia in preoperative semen analysis, it is advisable to ligate the contralateral vas deferens.

bubble_chart Prognosis

Simple male genital subcutaneous nodules have a better prognosis. They can generally be cured with aggressive drug therapy or a combination of medication and surgery. However, if severe urinary subcutaneous nodules are also present, treatment becomes difficult and the prognosis is poor.