Flashcards in Micro Enteric Viruses 2 Deck (25)
what does coxsackie A cause?
herpangina, hand-foot-and-mouth disease, acute hemorrhagic conjunctivitis
what is herpangina?
-acute febrile illness with small vesicular or ulcerative lesions on the posterior oropharyngeal structures that typically occurs in summer - mild and self-limited - typically children
what causes herpangina?
MC coxsackie A, but also by coxsackie B and other enteroviruses
what is hand-foot-and-mouth disease?
-spread by fecal-oral or contact with skin lesion/oral secretions
-viral invasion of mucus membranes causing widespread apoptosis with characteristic lesion formation (looks like chicken pox which is typically trunk)
-dehydration from refusal to drink/eat with sores
what causes hand foot and mouth disease?
MC coxsackie A, also coxsackie B and other enteroviruses
what is acute hemorrhagic conjunctivitis?
rapid onset painful conjunctivitis usually in young teens - unpleasant but short
-no treatment available
what causes acute hemorrhagic conjuncitivitis?
coxsackie group A24 also enterovirus
acute hemorrhagic conjunctivitis complications
rarely neurological sequelae - poliolike paralysis (1/10,000)
what does coxsackie A typically cause?
herpangina, hand foot mouth disease, acute hemorrhagic conunctivitis
what does coxsackie B typically cause?
viral myocarditis, pleurodynia
viral myocarditis pathogenesis
sequel in 1-4% coxsackie B gastroenteritis, necrosis of myocytes, inflammatory infiltrate interferes with heart function and may progress to CHF and pulmonary edema
what is seen on viral myocarditis exam - adults, infants, children?
-adults: heart failure, chest pain, dysrhythmia, RECENT HISTORY OF FLULIKE ILLNESS
-infants: irritability, lethary, periodic episodes of pallor, fever, hypothermia, tachypnea, anorexia, failure to thrive
-children: lack of energy, general malaise
viral myocarditis labwork
CBC (anemia, lymphcytosis, neutropenia), blood cultures to rule out bacterial infection, C-reactive protein and sedimentation rates (markers of inflammation), creatinine kinase, troponin 1 (myocardial damage)
histologic findings viral myocarditis (can be done on children and adults - not infants or super ill)
-focal or diffuse interstitial infiltrate of mononuclear cells, lymphocytes, plasma cells, eosinophils
-necrosis and diarrangement of myocytes
-fibroblasts in chronic and healing stages
what is pleurodynia
infection of striated muscle in chest (muscle necrosis around lung) - sudden occurrence of lancinating chest pain attacks
what causes pleurodynia?
coxsackie B and other enteroviruses
pain is paroxysmal, occurring in attacks separated by min-hr
-between attacks, patients usually have constant, dull pleuritic pain
-usually 3-5 days
3-5 days of fever, malaise, headache, sore throat/rhinitis/dry cough/n/v/diarrhea, pleural friction rub, herpangina or other mild coxsackie symptoms
what is seen on x ray of pleurodynia?
normal! because heart and lung are normal - muscle is abnormal (used for exclusion)
when is pleurodynia life-threatening?
aspectic meningitis pathogenesis
enterovirus breaches CNS, infects leptomeninges and immune response creates inflammation - normally self-limited but must rule out infection by bacteria or fungi
what is the classic tetrad for aseptic meningitis?
fever, meningisumus, irritability, photophobia
aspectic meningitis labwork
CSF: culture, gram stain, acid-fast stain; PCR for viruses; WBC count, protein level, glucose level (normal level for viruses, low for bacteria)
treatment for aseptic meningitis
rest, hydration, analgesics, anti-inflammatories