Fifth disease - 第五病
16個月大第五病 (Fifth disease) ― 兩頰變紅，像被打了一巴掌，身上出現斑丘疹。
兩頰有紅斑。
References
Fifth disease ，也稱為傳染性紅斑，是由人類細小病毒 B19 引起的病毒感染。它在兒童中更為普遍，通常影響 4 至 14 歲的兒童。症狀通常以輕微發燒、頭痛、喉嚨痛和類流感感覺開始。孩子們的臉上可能會出現類似 slapped cheeks 的明顯紅色皮疹，身體、手臂和腿部也會出現圖案化的皮疹。在成人中，關節疼痛是一種常見的症狀，可能在初次感染幾週後出現。值得注意的是，大約 20% 至 30% 的感染細小病毒 B19 的成年人可能不會表現出任何症狀。
Fifth disease (erythema infectiosum) is a viral infection caused by human parvovirus B19. It is more common in children than adults and usually affects children ages 4 to 14. The disease often starts with mild fever, headache, sore throat, and other flu-like symptoms. Children can also develop a bright red rash on the face that looks like “slapped cheeks”, along with a lacy or bumpy rash on the body, arms, and legs. In adults, joint aches are a common symptom. Rash and joint symptoms may develop several weeks after infection. About 20 to 30% of adults who are infected with parvovirus B19 will not have symptoms.
Fifth disease (erythema infectiosum) is a viral infection caused by human parvovirus B19. It is more common in children than adults and usually affects children ages 4 to 14. The disease often starts with mild fever, headache, sore throat, and other flu-like symptoms. Children can also develop a bright red rash on the face that looks like “slapped cheeks”, along with a lacy or bumpy rash on the body, arms, and legs. In adults, joint aches are a common symptom. Rash and joint symptoms may develop several weeks after infection. About 20 to 30% of adults who are infected with parvovirus B19 will not have symptoms.
Parvovirus B19 由母親傳給嬰兒的風險約為 33%，大約 3% 的受感染婦女的嬰兒會出現併發症。當母親在懷孕 20 週之前受到感染時，出現血液問題和嬰兒體內積水等併發症的機會就會增加。為了開始治療這種疾病，我們應該透過檢測某些抗體（IgM）來檢查患者是否曾經接觸過細小病毒。如果測試顯示過去沒有接觸過但表明最近感染過，則患者需要在懷孕期間進行密切監測，包括定期進行超音波掃描以檢查某些嬰兒健康問題。
The rate of vertical transmission during maternal parvovirus B19 infection is estimated at 33%, with fetal complications occurring in 3% of infected women. Fetal complications comprising hemolysis, anemia, and nonimmune hydrops fetalis and fetal loss are more frequent when maternal infection occurs before 20 weeks of gestation. The first step in the management of this patient would be to obtain immunoglobulin (Ig) M and IgG titres against parvovirus to evaluate if the patient has had previous immunity against the disease. If results are negative for IgG but positive for IgM (ie, primary infection), this patient would need close obstetrical monitoring for the following weeks, including serial ultrasounds to rule out fetal anemia and hydrops fetalis.
The rate of vertical transmission during maternal parvovirus B19 infection is estimated at 33%, with fetal complications occurring in 3% of infected women. Fetal complications comprising hemolysis, anemia, and nonimmune hydrops fetalis and fetal loss are more frequent when maternal infection occurs before 20 weeks of gestation. The first step in the management of this patient would be to obtain immunoglobulin (Ig) M and IgG titres against parvovirus to evaluate if the patient has had previous immunity against the disease. If results are negative for IgG but positive for IgM (ie, primary infection), this patient would need close obstetrical monitoring for the following weeks, including serial ultrasounds to rule out fetal anemia and hydrops fetalis.
第五病 (fifth disease) 以低燒、頭痛、皮疹和類似感冒的症狀（例如流鼻水或鼻塞）開始。這些症狀過去了，幾天後，皮疹出現。鮮紅色皮疹最常出現在臉部，尤其是臉頰。 （因此得名「拍打臉頰病」）。除了臉頰發紅之外，兒童也常在身體的其他部位出現紅色、花邊狀的皮疹，其中上臂、軀幹和腿部是最常見的部位。
這種疾病通常較輕，但在孕婦中，懷孕前三個月的感染與胎兒水腫有關，導致自然流產。
○ 治療
不需要特殊治療，因為它通常會隨著時間的推移而改善。