Mumps is a common respiratory infectious disease in preschool and school-age children. The causative agent is the mumps virus, which is transmitted through saliva droplets, so there are often many children in a class who are sick successively. The disease has an incubation period of 2 weeks, after the appearance of cold symptoms, parotid gland enlargement, characterized by earlobes as the center of the front, back, under the three directions of enlargement, local pain, pain in opening the mouth and eating, the skin is not red, and not pus. Usually it gets better in 1-2 weeks. However, sometimes children may develop redness and swelling of the scrotum around the 7th day after mumps, with simultaneous swelling of the testicles, pain or a sensation of falling, sometimes accompanied by fever and chills. Orchitis can also occur at the same time as mumps. The pain varies greatly in severity, and it is difficult to judge the extent of testicular injury based on the severity of the pain. It is generally recognized that mumps combined with orchitis is less common before puberty, so there is less chance of permanent testicular damage, and even if it is involved it usually recovers completely. After puberty, mumps is more likely to be associated with orchitis, so it is important to take care of mumps at this stage of life with bed rest and prompt treatment in order to avoid orchitis. Why are mumps patients prone to complications of orchitis? It turns out that one of the characteristics of the mumps virus is that it not only has an effect on the glands, but also on the nervous tissue, the pancreas, and especially on the testicles, which have a considerable affinity. Combined orchitis can be found in 1/5-1/4 of patients with mumps, in 2/3 of them the disease is unilateral, in 1/3 bilateral. The onset of the disease lasts 3-5 days and in severe cases up to 2 weeks. Testiculitis occurring after puberty can lead to irreparable damage to the epithelial and mesenchymal cells of the testicular flexure by the virus, which in severe cases can cause testicular atrophy. In addition, bilateral mumps orchitis in adult men can cause hypogonadism, sometimes accompanied by azoospermia or a severely reduced sperm count of less than 4 million/m1. The diagnosis of testicular inflammation is not difficult to establish, such as pain and discomfort in the testes with very sensitive and intense tenderness, together with swelling of one or both testes, with well-defined signs and symptoms, and of course, before the appearance of swelling and pain in the testes Of course, swelling and pain in the testicles are often preceded or accompanied by signs and symptoms of mumps. Sometimes only one side has signs, but this does not mean that the opposite testicle is not involved; degenerative lesions can still be seen in both testicles. When physical examination reveals an uneven texture and irregular shape of the testicles, this is often indicative of scarring. About half of the patients with bilateral orchitis have mild testicular atrophy. If the atrophy occurs in one testicle, it has less effect on fertility and does not affect the sex life after marriage; if both testicles are involved, it is likely to lead to infertility, and it has been reported that only 5% of patients are still fertile. However, when the size of testis is not significantly reduced, atrophy of the testicular flexure can still occur, which can seriously affect fertility. In severe cases of testicular atrophy, the size of the testis can be reduced to about 5 milliliters. When the cellular structure of the testis is destroyed and fibrosis occurs, not only the spermatogenic epithelial cells but also the mesenchymal cells are involved. In severe cases testicular biopsy can confirm a support cell only syndrome, where the patient does not have any spermatogenic cells present in the fine ducts. The fertility of these patients can be said to have no hope of recovery, yet some patients are still blindly seeking medical treatment, wasting much time, energy and medication. Some patients still have progressive fibrous degeneration of the testis several years after the disease. Even if the patient still has sperm production, the count may be within the normal range, but the viability of the sperm is often only about 30%, and the speed of movement is also significantly reduced. Other viral (e.g., coxsackievirus) infections can also cause orchitis and destroy its cellular components. The principles of therapeutic management of these patients are the same as those for mumps orchitis. Recent studies have shown that the feminization of the gynecomastia that occurs in adults with mumps orchitis is due to a significant impairment of the ability of the mesenchymal cells to secrete testosterone, while estrogen production is not impaired. Gynecomastia feminization is exacerbated by decreased androgen production, increased aromatization of androstenedione at sites outside the gonads, and increased estrogen production, resulting in an altered androgen/estrogen ratio. Because of the differences in incidence, treatment for prepubertal boys with mumps focuses on the mumps themselves; treatment for postpubertal men with mumps testicularis focuses on the testicularis. Supportive therapy includes strict bed rest, early treatment, careful care, localized placement of cold water bags on the testicles to reduce pain, and scrotal support using a thong belt to reduce symptoms (pain and swelling), thus preventing and minimizing the occurrence of sequelae. Administer adequate anti-inflammatory drugs and analgesics in a timely manner, especially if there is severe testicular pain. Putting the patient on estradiol, a gonadotropin inhibitor, can completely inhibit spermatogenesis in the testes, theoretically preventing viral damage to the varicocele due to blocking the development of the spermatogenic process. However, people often have difficulty tolerating this drug and will face nasty feminizing effects. It has also been used abroad to treat with danazol (800 mg daily in four divided doses), which has a similar effect on testicular inflammation treatment. It avoids the above mentioned side effects of hasenoestradiol. Prednisone 40-60 mg/day given in the acute phase can have some degree of symptomatic relief, but it should not be expected to have a dramatic effect. The use of gammaglobulin or human immunoglobulin serum in men who have had mumps can help protect fertility by greatly moderating the severity of the disease and slowing the severity of cellular damage.