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,
oralvaccine (RotaTeq") for use in children. The Advisory Committee on
ImmunizationPractices voted to recommend a newly licensed vaccine to protect
againstrotavirus. [CDC]
QUESTIONS
9 SinceJPs moderately dehydrated, the following schedule
isrecommended:
a. Rehydration phase with ORS:
Pedialyte1450 mL (100 mL/kg based on wt before diarrhea) within
4-6hr
b. Maintenance phase with ORS:
Pedialyte145 mL (10 mL/kg) for each diarrheal stool (not to exceed
150mL/kg/day)
c. Start feeding and advance astolerated
as described in the SOAPreport;
P: Problem 1: Viral Gastroenteritis
・Oralrehydration solution with Pedialyte
・Monitor frequency of stools
・Monitor weight
・Monitor Na+, K+, HCO3,
andglucose
・Startfeedings 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
freshfruits
・Avoidfree water, caffeine, carbonated
soft drinks,hyperosmolar fruit juices (i.e., specifically apple juice since
this iswhat JP has been consuming), and foods
high insimple sugars and fats
Problem
2:Dehydration
・Supportive care as outlined above
・Counsel parents on how to monitor for JP's condition (i.e.,
keeprecords of stool counts, oral intake, and JP's
mentalalertness)
・Recommend that parents bring JP back to clinic if he continues
toproduce frequent large-volume, watery stools
Pedialyte� Oral Electrolyte Maintenance
Solution--- InLiters, Freezer Pops, and Singles,
Pedialyte comes in multiple kid-pleasingflavors.
[http://www.pedialyte.com]
10.Instructions to JP's mom:
a. Attempt to give the recommendedvolume
of ORS to JP without forcing him to drink the solution to
avoidaspiration
b. Do not give JP any antidiarrheal agent
c. Avoid apple juice until
diarrheaabates
d. Return to clinic if JP continues
toproduce frequent large-volume, watery stools
e. Touch his lips to see if they are
nolonger dry and rough
11.Psychosocial factors to consider relative to JP's
outcomeinclude:
a. Assure JP's mom that her child
willrespond well if he can consume adequate oral fluid intake with Pedialyte
asdescribed previously
b. Ascertain if mom, dad, or a
caretakerfamiliar with JP can care for him during this bout of viral
gastroenteritisbecause JP will not be able to attend day
care
c. Make sure parents are
knowledgeableabout how to monitor JP's conditions by keeping records of stool
counts, oralintake, child's mental alertness
d. Reassure mom that she should
nothesitate to call you or the clinic if she has
anyquestions