ロタウイルス感染症
概念:
乳児期に流行性に発生する嘔吐下痢症.
主に冬季にみられる.
病因・疫学:
病因はロタウイルス (レオウイルス科2本鎖RNAウイルス).
エンベロープなし.
罹患年齢は乳幼児に多い.
家族内,
施設内感染が高率に起こる.
成人も罹患.
冬季にピーク.
感染経路は便中のウイルスによる経口感染.
同様のウイルス感染はロタウイルスの他に,
ノーウォークウイルス,
カリシウイルス,
腸性アデノウイルスなどによって起こる.
[写真はWikipedia]
症状:
潜伏期2-3日.
初発症状は頻回の嘔吐.
発熱や鼻汁などの感冒症状を伴う.
下痢は水様性,
約30%に米とぎ汁様の白色便が見られる.
下痢回数は10回/日におよび,
多くは脱水症状をともなう.
下痢は7-8日で治癒.
ときに痙攣や腸重積を合併.
診断:
季節と臨床症状から診断できる.
ただし細菌性下痢を見逃さないことが大切で,
診察医が観便を行うことが誤診防止につながる.
細菌培養は必須.
治療:
対症療法.
補液・食事療法.
[阿部:
小児科学新生児学テキスト]
[横田:
小児の薬の使い方･選び方]
予防:
In a report issued February 3rd, 2006, the U.S. FDA approved a live, oral
vaccine (RotaTeq") for use in children. The Advisory Committee on Immunization
Practices voted to recommend a newly licensed vaccine to protect against
rotavirus. [CDC]
QUESTIONS
9 Since
JPs moderately dehydrated, the following schedule is
recommended:
a. Rehydration phase with ORS: Pedialyte
1450 mL (100 mL/kg based on wt before diarrhea) within 4-6
hr
b. Maintenance phase with ORS: Pedialyte
145 mL (10 mL/kg) for each diarrheal stool (not to exceed 150
mL/kg/day)
c. Start feeding and advance as
tolerated as described in the SOAP
report;
P: Problem 1: Viral Gastroenteritis
・Oral
rehydration solution with Pedialyte
・Monitor frequency of stools
・Monitor weight
・Monitor Na+, K+, HCO3, and
glucose
・Start
feedings initially with easily digested foods such as bananas, applesauce,
and cereal, and advance as tolerated
・Subsequent foods can include complex carbohydrates (potatoes,
bread), lean meats, yogurt, vegetables, and fresh
fruits
・Avoid
free water, caffeine, carbonated soft drinks,
hyperosmolar fruit juices (i.e., specifically apple juice since this is
what JP has been consuming), and foods high in
simple sugars and fats
Problem 2:
Dehydration
・Supportive care as outlined above
・Counsel parents on how to monitor for JP's condition (i.e., keep
records of stool counts, oral intake, and JP's mental
alertness)
・Recommend that parents bring JP back to clinic if he continues to
produce frequent large-volume, watery stools
Pedialyte
